HT66FB5x0v140.pdf

A/D Flash USB 8-Bit MCU with SPI
HT66FB540/HT66FB542
HT66FB550/HT66FB560
Revision: V1.40 Date: ������������������
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
Table of Contents
Features............................................................................................................. 7
CPU Features.......................................................................................................................... 7
Peripheral Features.................................................................................................................. 8
General Description.......................................................................................... 9
Selection Table................................................................................................ 10
Block Diagram................................................................................................. 10
Pin Assignment................................................................................................11
Pin Description............................................................................................... 15
Absolute Maximum Ratings........................................................................... 26
D.C. Characteristics........................................................................................ 27
A.C. Characteristics........................................................................................ 29
LVD & LVR Electrical Characteristics........................................................... 30
ADC Electrical Characteristics...................................................................... 31
Comparator Electrical Characteristics......................................................... 31
Power on Reset (AC+DC) Electrical Characteristics................................... 31
System Architecture....................................................................................... 32
Clocking and Pipelining.......................................................................................................... 32
Program Counter.................................................................................................................... 33
Stack...................................................................................................................................... 34
Arithmetic and Logic Unit – ALU............................................................................................ 34
Flash Program Memory.................................................................................. 35
Structure................................................................................................................................. 35
Special Vectors...................................................................................................................... 35
Look-up Table......................................................................................................................... 36
Table Program Example......................................................................................................... 36
In System Programming – ISP............................................................................................... 37
In Application Programming – IAP......................................................................................... 43
In Circuit Programming – ICP................................................................................................ 47
On-Chip Debug Support – OCDS.......................................................................................... 48
RAM Data Memory.......................................................................................... 49
Structure................................................................................................................................. 49
Special Function Register Description......................................................... 54
Indirect Addressing Registers – IAR0, IAR1.......................................................................... 54
Memory Pointers – MP0, MP1............................................................................................... 54
Bank Pointer – BP.................................................................................................................. 55
Accumulator – ACC................................................................................................................ 56
Program Counter Low Register – PCL................................................................................... 57
Look-up Table Registers – TBLP, TBHP, TBLH...................................................................... 57
Status Register – STATUS..................................................................................................... 57
Rev. 1.40
2
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
Oscillators....................................................................................................... 59
Oscillator Overview................................................................................................................ 59
System Clock Configurations................................................................................................. 59
External Crystal Oscillator – HXT........................................................................................... 60
Internal PLL Frequency Generator......................................................................................... 61
Internal RC Oscillator – HIRC................................................................................................ 63
External 32.768kHz Crystal Oscillator – LXT......................................................................... 63
Internal 32kHz Oscillator – LIRC............................................................................................ 65
Supplementary Internal Clocks.............................................................................................. 65
Operating Modes and System Clocks.......................................................... 65
System Clocks....................................................................................................................... 65
System Operation Modes....................................................................................................... 67
Control Register..................................................................................................................... 68
Fast Wake-up......................................................................................................................... 70
Operating Mode Switching and Wake-up............................................................................... 71
Standby Current Considerations............................................................................................ 75
Wake-up................................................................................................................................. 75
Programming Considerations................................................................................................. 76
Watchdog Timer.............................................................................................. 77
Watchdog Timer Clock Source............................................................................................... 77
Watchdog Timer Control Register.......................................................................................... 77
Watchdog Timer Operation.................................................................................................... 78
WDT Enable/Disabled using the WDT Control Register........................................................ 79
Reset and Initialisation................................................................................... 80
Reset Overview...................................................................................................................... 80
Reset Functions..................................................................................................................... 81
WDTC Register Software Reset ........................................................................................... 84
Reset Initial Conditions.......................................................................................................... 85
Input/Output Ports.......................................................................................... 98
Pull-high Resistors............................................................................................................... 101
Port Wake-up....................................................................................................................... 103
Port A Wake-up Polarity Control Register ........................................................................... 105
I/O Port Control Registers.................................................................................................... 105
I/O Output Current Control Registers .................................................................................. 107
I/O Output Slew Rate Control Registers.............................................................................. 109
Port A Power Source Control Registers ...............................................................................111
I/O Pin Structures..................................................................................................................112
Programming Considerations................................................................................................113
Rev. 1.40
3
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
Timer Modules – TM......................................................................................114
Introduction...........................................................................................................................114
TM Operation........................................................................................................................114
TM Clock Source...................................................................................................................115
TM Interrupts.........................................................................................................................115
TM External Pins...................................................................................................................115
TM Input/Output Pin Control Registers.................................................................................116
Programming Considerations............................................................................................... 122
Compact Type TM – CTM............................................................................. 123
Compact TM Operation........................................................................................................ 123
Compact Type TM Register Description.............................................................................. 124
Compact Type TM Operating Modes................................................................................... 128
Standard Type TM – STM............................................................................. 134
Standard TM Operation........................................................................................................ 134
Standard Type TM Register Description.............................................................................. 135
Standard Type TM Operating Modes................................................................................... 143
Analog to Digital Converter......................................................................... 153
A/D Overview....................................................................................................................... 153
A/D Converter Register Description..................................................................................... 153
A/D Converter Data Registers – ADRL, ADRH.................................................................... 154
A/D Converter Control Registers – ADCR0, ADCR1, ACER0, ACER1................................ 155
A/D Operation...................................................................................................................... 161
A/D Input Pins...................................................................................................................... 162
Summary of A/D Conversion Steps...................................................................................... 162
Programming Considerations............................................................................................... 163
A/D Transfer Function.......................................................................................................... 163
A/D Programming Example.................................................................................................. 164
Comparators................................................................................................. 166
Comparator Operation......................................................................................................... 166
Comparator Registers.......................................................................................................... 166
Comparator Interrupt............................................................................................................ 166
Programming Considerations............................................................................................... 167
Serial Interface Module – SIM...................................................................... 169
SPI Interface........................................................................................................................ 169
I2C Interface......................................................................................................................... 178
Serial Interface – SPIA ................................................................................. 189
SPIA Interface Operation..................................................................................................... 189
SPIA Registers..................................................................................................................... 190
SPIA Communication........................................................................................................... 193
SPIA Bus Enable/Disable..................................................................................................... 195
SPIA Operation.................................................................................................................... 196
Error Detection..................................................................................................................... 197
Rev. 1.40
4
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
Peripheral Clock Output............................................................................... 198
Peripheral Clock Operation.................................................................................................. 198
Interrupts....................................................................................................... 199
Interrupt Registers................................................................................................................ 199
Interrupt Operation............................................................................................................... 207
External Interrupt.................................................................................................................. 210
Comparator Interrupt............................................................................................................ 210
USB Interrupt....................................................................................................................... 210
Multi-function Interrupt..........................................................................................................211
A/D Converter Interrupt.........................................................................................................211
Time Base Interrupts – HT66FB540/HT66FB550/HT66FB560.............................................211
Serial Interface Module Interrupts – SIM Interrupt............................................................... 212
Serial Peripheral Interface Interrupt – SPIA Interrupt........................................................... 213
LVD Interrupt........................................................................................................................ 213
TM Interrupts........................................................................................................................ 213
Interrupt Wake-up Function.................................................................................................. 213
Programming Considerations............................................................................................... 214
Low Voltage Detector – LVD........................................................................ 215
LVD Register........................................................................................................................ 215
LVD Operation...................................................................................................................... 216
USB Interface................................................................................................ 217
Power Plane......................................................................................................................... 217
USB Suspend Wake-Up Remote Wake-Up......................................................................... 218
USB Interface Operation...................................................................................................... 219
USB Interface Registers....................................................................................................... 220
Configuration Options.................................................................................. 240
Application Circuits...................................................................................... 241
Instruction Set............................................................................................... 242
Introduction.......................................................................................................................... 242
Instruction Timing................................................................................................................. 242
Moving and Transferring Data.............................................................................................. 242
Arithmetic Operations........................................................................................................... 242
Logical and Rotate Operation.............................................................................................. 243
Branches and Control Transfer............................................................................................ 243
Bit Operations...................................................................................................................... 243
Table Read Operations........................................................................................................ 243
Other Operations.................................................................................................................. 243
Rev. 1.40
5
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
Instruction Set Summary............................................................................. 244
Table Conventions................................................................................................................ 244
Instruction Definition.................................................................................... 246
Package Information.................................................................................... 255
24-pin SSOP (150mil) Outline Dimensions.......................................................................... 256
28-pin SSOP(150mil) Outline Dimensions........................................................................... 257
SAW Type 40-pin (6mm × 6mm for 0.75mm) QFN Outline Dimensions.............................. 258
48-pin LQFP (7mm × 7mm) Outline Dimensions................................................................. 259
64-pin LQFP (7mm × 7mm) Outline Dimensions................................................................. 260
Rev. 1.40
6
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
Features
CPU Features
• Operating voltage
♦♦
VDD(MCU):
fSYS=4MHz/6MHz: 2.2V~5.5V
fSYS=12MHz: 2.7V~5.5V
♦♦
VDD (USB mode):
fSYS=6MHz/12MHz: 3.3V~5.5V
fSYS=16MHz: 4.5V~5.5V
• Up to 0.25μs instruction cycle with 16MHz system clock at VDD=5V
• Power down and wake-up functions to reduce power consumption
• Four oscillators
♦♦
External Crystal – HXT
♦♦
External 32.768kHz Crystal – LXT (Only available in HT66FB540/HT66FB550/HT66FB560)
♦♦
Internal RC – HIRC
♦♦
Internal 32kHz RC – LIRC
• Multi-mode operation: NORMAL, SLOW, IDLE and SLEEP
• All instructions executed in one or two instruction cycles
• Table read instructions
• 62 powerful instructions
• Up to 12-level subroutine nesting
• Bit manipulation instruction
Rev. 1.40
7
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
Peripheral Features
• Flash Program Memory: 4K×16~16K×16
• RAM Data Memory: 256×8~1024×8
• USB 2.0 Full Speed compatible
• Up to 8 endpoints supported including endpoint 0
• All endpoints except endpoint 0 can support interrupt and bulk transfer
• All endpoints except endpoint 0 can be configured as 8, 16, 32, 64 bytes FIFO size
• Endpoint 0 support control transfer
• Endpoint 0 has 8 byte FIFO
• Support 3.3V LDO and internal UDP 1.5kΩ pull-up resistor
• Internal 12MHz RC OSC with 0.25% accuracy for all USB modes
• Watchdog Timer function
• Up to 45 bidirectional I/O lines
• Dual pin-shared external interrupts
• Multiple Timer Modules for time measurement, input capture, compare match output or PWM
output or single pulse output function
♦♦
2 Compact type 10-bit Timer Modules – CTM
♦♦
1 Standard type 10-bit Timer Module – STM
♦♦
1 Standard type 16-bit Timer Module – STM
• Serial Interface Modules with Dual SPI and I2C interfaces
• Single Serial Peripheral Interface – SPIA
• Up to Dual Comparator functions
• Dual Time-Base functions for generation of fixed time interrupt signals
• Up to 16 channel 12-bit resolution A/D converter
• Low voltage reset function
• Low voltage detect function
• Flash program memory can be re-programmed up to 1,000,000 times
• Flash program memory data retention > 10 years
• Support In Application Programming function – IAP
• Support In System Programing function – ISP
• Wide range of available package types
Rev. 1.40
8
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
General Description
These devices are Flash Memory A/D with USB type 8-bit high performance RISC architecture
microcontrollers, designed for applications that interface directly to analog signals and which require
an USB interface. Offering users the convenience of Flash Memory multi-programming features,
these devices also include a wide range of functions and features. Other memory includes an area of
RAM Data Memory.
Analog features include a multi-channel 12-bit A/D converter and dual comparator functions. Multiple
and extremely flexible Timer Modules provide timing, pulse generation and PWM generation
functions. Communication with the outside world is catered for by including fully integrated SPI, I2C
and USB interface functions, three popular interfaces which provide designers with a means of easy
communication with external peripheral hardware. Protective features such as an internal Watchdog
Timer, Low Voltage Reset and Low Voltage Detector coupled with excellent noise immunity and ESD
protection ensure that reliable operation is maintained in hostile electrical environments. The external
interrupt can be triggered with falling edges or both falling and rising edges.
A full choice of four oscillator functions are provided including two fully integrated system
oscillators which requires no external components for their implementation. The ability to operate
and switch dynamically between a range of operating modes using different clock sources gives
users the ability to optimize microcontroller operation and minimize power consumption.
The inclusion of flexible I/O programming features, Time-Base functions along with many other
features ensure that these devices will find specific excellent use in a wide range of application
possibilities such as sensor signal processing, motor driving, industrial control, consumer products,
subsystem controllers, etc.
These devices are fully supported by the Holtek range of fully functional development and
programming tools, providing a means for fast and efficient product development cycles.
Rev. 1.40
9
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
Selection Table
Most features are common to all devices, the main feature distinguishing them are Program Memory
capacity, I/O count, A/D channels, stack capacity, LXT, comparator and package types. The
following table summarises the main features of each device.
Program
Memory
Data
Memory
I/O
External
Interrupt
A/D
Timer
Module
HT66FB540 2.2V~5.5V
4K×16
512×8
25
2
12-bit×8
10-bit CTM×2,
10-bit STM×1,
16-bit STM×1
HT66FB542 2.2V~5.5V
4K×16
256×8
17
2
12-bit×4
10-bit CTM×2,
10-bit STM×1,
16-bit STM×1
HT66FB550 2.2V~5.5V
8K×16
768×8
37
2
12-bit×16
10-bit CTM×2,
10-bit STM×1,
16-bit STM×1
HT66FB560 2.2V~5.5V
16K×16
1024×8
45
2
12-bit×16
10-bit CTM×2,
10-bit STM×1,
16-bit STM×1
Part No.
VDD
Part No.
SIM (SPI/I2C)
SPIA
LXT
Comparator
Stack
Package
HT66FB540
√
√
√
2
8
28SSOP
48LQFP
HT66FB542
√
√
—
1
8
24SSOP
HT66FB550
√
√
√
2
8
28SSOP
40QFN
48LQFP
HT66FB560
√
√
√
2
12
40QFN
48/64LQFP
Block Diagram
Flash
P�og�a��ing
Ci�cuit�y
U�B �.0
XCVR
3.3V
LDO
Inte�nal
HIRC/LIRC
Oscillato�s
Watchdog
Ti�e�
LVD/
LVR
Flash
P�og�a�
Me�o�y
U�B �.0
Full ��eed
Engine
RAM
Data
Me�o�y
Reset
Ci�cuit
Inte��u�t
Cont�olle�
�-�it
RI�C
MCU
Co�e
Exte�nal
HXT
Oscillato�
Ti�e
Bases
Exte�nal
LXT
Oscillato�
Fo� HT66F�40/��0/�60
1�-�it A/D
Conve�te�
�IM
(�PI/I�C)
�PIA
I/O
Ti�e�
Modules
Co��a�ato�s
Rev. 1.40
10
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
Pin Assignment
HT66FB540
PA3/�CKA/C0-
1
��
PA4/�C�A/TP0_0/C1X
PA�/�DIA/C0+
�
�7
PA�/TP1_0/C1+
PA1/�DOA/C0X
3
�6
PA6/TCK0/C1-
PA0/TCK1/OCD�DA
4
��
PA7/INT0/AN7
UDN/GPIO0/ICPDA
�
�4
PE0/VDDIO/VREF
UDP/GPIO1
6
�3
PB6/INT1/AN6
V33O
7
��
PB�/PCK/AN�
UBU�/PE1/AVDD/VDD
�
�1
PB4/TP0_1/AN4
HVDD
9
�0
PB3/�C�/AN3
V��
PE3/XT1
PE4/XT�
10
19
1�
PB�/�CK/AN�
11
1�
17
RE�/OCD�CK/ICPCK
13
16
PB1/�DI/�CL/AN1
PB0/�DO/�DA/AN0
PD1/TP�_1/O�C�
PE�
14
1�
PD0/TP3_1/O�C1
HT66FB540/HT66VB540
28 SSOP-A
NC
NC
NC
NC
PE0/VDDIO/VREF
PA7/INT0/AN7
PA6/TCK0/C1PA�/TP1_0/C1+
PA4/�C�A/TP0_0/C1X
PA3/�CKA/C0PA�/�DIA/C0+
PA1/�DOA/C0X
PA0/TCK1/OCD�DA
NC
UDN/GPIO0/ICPDA
UDP/GPIO1
V33O
UBU�/PE1/AVDD/VDD
HVDD
V��
PE3/XT1
PE4/XT�
RE�/OCD�CK/ICPCK
PE�
4� 47 46 4� 44 43 4� 41 40 39 3� 37
36
1
3�
�
34
3
4
33
�
3�
31
6 HT66FB540/HT66VB540
7
30
48 LQFP-A
�9
�
��
9
�7
10
�6
11
��
1�
13 14 1�16 17 1� 19 �0 �1 �� �3 �4
NC
NC
NC
NC
NC
PB6/INT1/AN6
PB�/PCK/AN�
PB4/TP0_1/AN4
PB3/�C�/AN3
PB�/�CK/AN�
PB1/�DI/�CL/AN1
PB0/�DO/�DA/AN0
NC
NC
NC
NC
NC
PD�/TP1_1
PD4/TCK3
PD3
PD�/TCK�
PD1/TP�_1/O�C�
PD0/TP3_1/O�C1
NC
Rev. 1.40
11
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
HT66FB542
PA�/�DIA/C0+
1
�4
PA3/�CKA/C0-
PA1/�DOA/C0X
�
�3
PA4/�C�A/TP0_0
PA0/TCK1/OCD�DA
3
��
PA�/TP1_0/INT1
UDN/GPIO0/ICPDA
4
�1
PE0/VDDIO/VREF
UDP/GPIO1
�
�0
PA7/INT0/AN3
V33O
6
19
PA6/TCK0
PE1/UBU�/VDD
7
1�
PB1/�DI/�CL/AN1
HVDD
�
17
PB0/�DO/�DA/AN0
V��
9
16
PB�/�CK/AN�
RE�/OCD�CK/ICPCK
10
1�
PB3/�C�
PD0/TP3_1/O�C1
11
14
PD4/TCK3/PCK
PD1/TP�_1/O�C�
1�
13
PD�/TCK�
HT66FB542/HT66VB542
24 SSOP-A
HT66FB550
PA3/�CKA/C0-
1
��
PA4/�C�A/TP0_0/C1X
PA�/�DIA/C0+
�
�7
PA�/TP1_0/C1+
PA1/�DOA/C0X
3
�6
PA6/TCK0/C1-
PA0/TCK1/OCD�DA
4
��
PA7/INT0/AN7
UDN/GPIO0/ICPDA
�
�4
PE0/VDDIO/VREF
UDP/GPIO1
V33O
6
�3
7
��
PB6/INT1/AN6
PB�/PCK/AN�
UBU�/PE1/AVDD/VDD
�
�1
PB4/TP0_1/AN4
HVDD
9
�0
PB3/�C�/AN3
V��
PE3/XT1
10
19
PB�/�CK/AN�
11
1�
PE4/XT�
1�
17
RE�/OCD�CK/ICPCK
PE�
13
16
PB1/�DI/�CL/AN1
PB0/�DO/�DA/AN0
PD1/TP�_1/O�C�
14
1�
PD0/TP3_1/O�C1
HT66FB550/HT66VB550
28 SSOP-A
Rev. 1.40
12
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
PC6/AN14
PC7/AN1�
PE0/VDDIO/VREF
PA7/INT0/AN7
PA6/TCK0/C1PA�/TP1_0/C1+
PA4/�C�A/TP0_0/C1X
PA3/�CKA/C0PA�/�DIA/C0+
PA1/�DOA/C0X
PA0/TCK1/OCD�DA
UDN/GPIO0/ICPDA
UDP/GPIO1
V33O
UBU�/PE1/AVDD/VDD
HVDD
V��
PE3/XT1
PE4/XT�
RE�/OCD�CK/ICPCK
40 39 3� 37 36 3� 34 33 3� 31
1
30
�
�9
��
3
4
�7
� HT66FB550/HT66VB550 �6
6
��
40 QFN-A
7
�4
�
�3
9
��
10
�1
11 1� 13 14 1�16 17 1� 19 �0
PA0/TCK1/OCD�DA
NC
UDN/GPIO0/ICPDA
UDP/GPIO1
V33O
UBU�/PE1/AVDD/VDD
HVDD
V��
PE3/XT1
PE4/XT�
RE�/OCD�CK/ICPCK
PE�
4� 47 46 4� 44 43 4� 41 40 39 3� 37
36
1
3�
�
34
3
4
33
�
3�
6
HT66FB550/HT66VB550 31
7
30
48 LQFP-A
�9
�
��
9
�7
10
�6
11
��
1�
13 14 1�16 17 1� 19 �0 �1 �� �3 �4
PC�/AN13
PC�/AN10
PC1/AN9
PC0/AN�
PB7
PB6/INT1/AN6
PB�/PCK/AN�
PB4/TP0_1/AN4
PB3/�C�/AN3
PB�/�CK/AN�
PB1/�DI/�CL/AN1
PB0/�DO/�DA/AN0
PD6/TP3_0
PD�/TP1_1
PD4/TCK3
PD3
PD�/TCK�
PD1/TP�_1/O�C�
PD0/TP3_1/O�C1
PE�
PC4/AN1�
PC�/AN13
PC6/AN14
PC7/AN1�
PE0/VDDIO/VREF
PA7/INT0/AN7
PA6/TCK0/C1PA�/TP1_0/C1+
PA4/�C�A/TP0_0/C1X
PA3/�CKA/C0PA�/�DIA/C0+
PA1/�DOA/C0X
PC3/AN11
PC�/AN10
PC1/AN9
PC0/AN�
PB7
PB6/INT1/AN6
PB�/PCK/AN�
PB4/TP0_1/AN4
PB3/�C�/AN3
PB�/�CK/AN�
PB1/�DI/�CL/AN1
PB0/�DO/�DA/AN0
NC
NC
NC
PD7/TP�_0
PD6/TP3_0
PD�/TP1_1
PD4/TCK3
PD3
PD�/TCK�
PD1/TP�_1/O�C�
PD0/TP3_1/O�C1
PE�
Rev. 1.40
13
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
HT66FB560
PC6/AN14
PC7/AN1�
PE0/VDDIO/VREF
PA7/INT0/AN7
PA6/TCK0/C1PA�/TP1_0/C1+
PA4/�C�A/TP0_0/C1X
PA3/�CKA/C0PA�/�DIA/C0+
PA1/�DOA/C0X
40 39 3� 37 36 3� 34 33 3� 31
30
1
�
�9
��
3
4
�7
HT66FB560/
�
HT66VB560
�6
6
��
40 QFN-A
7
�4
�
�3
9
��
10
�1
11 1� 13 14 1�16 17 1� 19 �0
PC�/AN13
PC�/AN10
PC1/AN9
PC0/AN�
PB7
PB6/INT1/AN6
PB�/PCK/AN�
PB4/TP0_1/AN4
PB3/�C�/AN3
PB�/�CK/AN�
PB1/�DI/�CL/AN1
PB0/�DO/�DA/AN0
PD6/TP3_0
PD�/TP1_1
PD4/TCK3
PD3
PD�/TCK�
PD1/TP�_1/O�C�
PD0/TP3_1/O�C1
PE�
PA0/TCK1/OCD�DA
NC
UDN/GPIO0/ICPDA
UDP/GPIO1
V33O
UBU�/PE1/AVDD/VDD
HVDD
V��
PE3/XT1
PE4/XT�
RE�/OCD�CK/ICPCK
PE�
64 63 6� 61 60 �9 �� �7 �6 �� �4 �3 �� �1 �0 49
1
4�
�
47
3
46
4
4�
44
�
6
43
4�
7
�
41
HT66FB560/HT66VB560
40
9
64 LQFP-A
10
39
3�
11
1�
37
36
13
3�
14
34
1�
33
16
17 1� 19 �0 �1 �� �3 �4 �� �6 �7 �� �9 30 31 3�
4� 47 46 4� 44 43 4� 41 40 39 3� 37
36
1
3�
�
34
3
4
33
�
3�
6
HT66FB560/HT66VB560 31
7
30
48 LQFP-A
�9
�
��
9
�7
10
�6
11
��
1�
13 14 1�16 17 1� 19 �0 �1 �� �3 �4
PC3/AN11
PC�/AN10
PC1/AN9
PC0/AN�
PB7
PB6/INT1/AN6
PB�/PCK/AN�
PB4/TP0_1/AN4
PB3/�C�/AN3
PB�/�CK/AN�
PB1/�DI/�CL/AN1
PB0/�DO/�DA/AN0
NC
NC
NC
PD7/TP�_0
PD6/TP3_0
PD�/TP1_1
PD4/TCK3
PD3
PD�/TCK�
PD1/TP�_1/O�C�
PD0/TP3_1/O�C1
PE�
NC
PC4/AN1�
PC�/AN13
PC6/AN14
PC7/AN1�
PE0/VDDIO/VREF
PA7/INT0/AN7
PA6/TCK0/C1PA�/TP1_0/C1+
PA4/�C�A/TP0_0/C1X
PA3/�CKA/C0PA�/�DIA/C0+
PA1/�DOA/C0X
PA0/TCK1/OCD�DA
NC
NC
NC
NC
UDN/GPIO0/ICPDA
UDP/GPIO1
V33O
UBU�/PE1/AVDD/VDD
HVDD
V��
PE3/XT1
PE4/XT�
NC
RE�/OCD�CK/ICPCK
NC
NC
NC
PE�
PC4/AN1�
PC�/AN13
PC6/AN14
PC7/AN1�
PE0/VDDIO/VREF
PA7/INT0/AN7
PA6/TCK0/C1PA�/TP1_0/C1+
PA4/�C�A/TP0_0/C1X
PA3/�CKA/C0PA�/�DIA/C0+
PA1/�DOA/C0X
PA0/TCK1/OCD�DA
UDN/GPIO0/ICPDA
UDP/GPIO1
V33O
UBU�/PE1/AVDD/VDD
HVDD
V��
PE3/XT1
PE4/XT�
RE�/OCD�CK/ICPCK
PC3/AN11
PC�/AN10
PC1/AN9
PC0/AN�
PB7
PB6/INT1/AN6
PB�/PCK/AN�
PB4/TP0_1/AN4
PB3/�C�/AN3
PB�/�CK/AN�
NC
PB1/�DI/�CL/AN1
PB0/�DO/�DA/AN0
NC
NC
PF7
PF6
PF�
PF4
PF3
PF�
PF1
PF0
PD7/TP�_0
PD6/TP3_0
PD�/TP1_1
PD4/TCK3
PD3
PD�/TCK�
PD1/TP�_1/O�C�
PD0/TP3_1/O�C1
PE�
Note: 1. If the pin-shared pin functions have multiple outputs simultaneously, its pin names at the right side of the "/"
sign can be used for higher priority.
2. The OCDSDA and OCDSCK pins are supplied for the OCDS dedicated pins and as such only available
for the HT66VB540/542/550/560 device which is the OCDS EV chip for the HT66FB540/542/550/560
device.
Rev. 1.40
14
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
Pin Description
The pins on these devices can be referenced by their Port name, e.g. PA.0, PA.1 etc, which refer to
the digital I/O function of the pins. However these Port pins are also shared with other functions
such as the Analog to Digital Converter, Serial Port pins etc. The function of each pin is listed in the
following table, however the details behind how each pin is configured is contained in other sections
of the datasheet.
HT66FB540
Pin Name
PA0/TCK1/OCDSDA
PA1/SDOA/C0X
PA2/SDIA/C0+
PA3/SCKA/C0-
PA4/SCSA/TP0_0/C1X
PA5/TP1_0/C1+
PA6/TCK0/C1-
PA7/INT0/AN7
PB0/SDO/SDA/AN0
PB1/SDI/SCL/AN1
Rev. 1.40
Function
OPT
I/T
PA0
PAPU
PAWU
ST
O/T
Description
CMOS General purpose I/O. Register enabled pull-up and wake-up
TCK1
—
ST
OCDSDA
—
ST
CMOS OCDS Data/Address, for EV chip only
—
TM1 input
PA1
PAPU
PAWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
SDOA
—
—
CMOS SPIA Data output
C0X
—
—
CMOS Comparator 0 output
PA2
PAPU
PAWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
SDIA
—
ST
—
SPIA Data input
C0+
—
AN
—
Comparator 0 positive input
PA3
PAPU
PAWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
NMOS SPIA Serial Clock
SCKA
—
ST
C0-
—
AN
PA4
PAPU
PAWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
—
Comparator 0 negative input
SCSA
—
ST
CMOS SPIA Slave select
TP0_0
TMPC0
ST
CMOS TM0 I/O
C1X
—
—
CMOS Comparator 1 output
PA5
PAPU
PAWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
TP1_0
TMPC0
ST
CMOS TM1 I/O
C1+
—
AN
PA6
PAPU
PAWU
ST
—
Comparator 1 positive input
CMOS General purpose I/O. Register enabled pull-up and wake-up
TCK0
—
ST
—
TM0 input
C1-
—
AN
—
Comparator 1 negative input
PA7
PAPU
PAWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
INT0
—
ST
—
External interrupt 0
AN7
ACER0
AN
—
A/D Channel 7
PB0
PXPU
PXWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
SDO
—
—
CMOS SPI Data output
SDA
—
ST
NMOS I2C Data
AN0
ACER0
AN
PB1
PXPU
PXWU
ST
SDI
—
ST
SCL
—
ST
AN1
ACER0
AN
—
A/D Channel 0
CMOS General purpose I/O. Register enabled pull-up and wake-up
—
SPI Data input
NMOS I2C Clock
—
A/D Channel 1
15
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
Pin Name
PB2/SCK/AN2
PB3/SCS/AN3
PB4/TP0_1/AN4
PB5/PCK/AN5
PB6/INT1/AN6
PD0/TP3_1/OSC1
PD1/TP2_1/OSC2
PD2/TCK2
PD3
PD4/TCK3
PD5/TP1_1
PE0/VDDIO/VREF
PE1/UBUS
PE2
PE3/XT1
PE4/XT2
Rev. 1.40
Function
OPT
I/T
PB2
PXPU
PXWU
O/T
Description
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
CMOS SPI Serial Clock
SCK
—
ST
AN2
ACER0
AN
PB3
PXPU
PXWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
CMOS SPI Slave select
—
A/D Channel 2
SCS
—
ST
AN3
ACER0
AN
PB4
PXPU
PXWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
TP0_1
TMPC0
ST
CMOS TM0 I/O
AN4
ACER0
AN
PB5
PXPU
PXWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
CMOS Peripheral output clock
PCK
—
—
AN5
ACER0
AN
PB6
PXPU
PXWU
ST
—
—
—
A/D Channel 3
A/D Channel 4
A/D Channel 5
CMOS General purpose I/O. Register enabled pull-up and wake-up
INT1
—
ST
—
External interrupt 1
AN6
ACER0
AN
—
A/D Channel 6
PD0
PXPU
PXWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
TP3_1
TMPC1
ST
CMOS TM3 I/O
OSC1
CO
HXT
PD1
PXPU
PXWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
TP2_1
TMPC1
ST
CMOS TM2 I/O
OSC2
CO
—
PD2
PXPU
PXWU
ST
TCK2
—
ST
PD3
PXPU
PXWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
PD4
PXPU
PXWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
TCK3
TMPC1
ST
PD5
PXPU
PXWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
TP1_1
TMPC0
ST
CMOS TM1 I/O
PE0
PXPU
PXWU
CO
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
VDDIO
CO
PWR
—
PA external power input
VREF
—
AN
—
ADC reference power input
PE1
—
ST
—
General purpose I/O. Input only
UBUS
—
PWR
—
USB SIE VDD
PE2
PXPU
PXWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
PE3
PXPU
PXWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
XT1
CO
LXT
PE4
PXPU
PXWU
ST
XT2
CO
—
—
HXT
HXT pin
HXT pin
CMOS General purpose I/O. Register enabled pull-up and wake-up
—
—
—
TM2 input
TM3 input
LXT pin
CMOS General purpose I/O. Register enabled pull-up and wake-up
LXT
LXT pin
16
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
Pin Name
Function
OPT
I/T
O/T
RES
—
ST
—
Reset input
RES/OCDSCK/ICPCK OCDSCK
Description
—
ST
—
OCDS clock, for EV chip only
ICPCK
—
ST
—
ICP clock
UDN
—
ST
CMOS USB UDN line
GPIO0
—
ST
CMOS General purpose I/O
ICPDA
—
ST
CMOS ICP Data/Address
UDP
—
ST
CMOS USB UDP line
GPIO1
—
ST
CMOS General purpose I/O
VDD/AVDD
VDD/
AVDD
—
PWR
—
Power supply
VSS/AVSS
VSS/
AVSS
—
PWR
—
Ground
V33O
V33O
—
—
PWR
HVDD
HVDD
—
PWR
—
UDN/GPIO0/ICPDA
UDP/GPIO1
3.3V regulator output
HIRC oscillator Positive Power supply
Note: I/T: Input type;
O/T: Output type
OPT: Optional by configuration option (CO) or register option
PWR: Power;
CO: Configuration option
ST: Schmitt Trigger input;
CMOS: CMOS output;
HXT: High frequency crystal oscillator
LXT: Low frequency crystal oscillator
AN: Analog signal
Where devices exist in more than one package type the table reflects the situation for the package with the largest
number of pins. For this reason not all pins described in the table may exist on all package types.
Rev. 1.40
17
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
HT66FB542
Pin Name
PA0/TCK1/OCDSDA
PA1/SDOA/C0X
PA2/SDIA/C0+
PA3/SCKA/C0-
PA4/SCSA/TP0_0
PA5/TP1_0/INT1
PA6/TCK0
PA7/INT0/AN3
PB0/SDO/SDA/AN0
PB1/SDI/SCL/AN1
PB2/SCK/AN2
PB3/SCS
Rev. 1.40
Function
OPT
I/T
PA0
PAPU
PAWU
O/T
Description
ST
TCK1
—
ST
OCDSDA
—
ST
CMOS OCDS Data/Address, for EV chip only
PA1
PAPU
PAWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
SDOA
—
—
CMOS SPIA Data output
C0X
—
—
CMOS Comparator output
PA2
PAPU
PAWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
CMOS General purpose I/O. Register enabled pull-up and wake-up
—
TM1 input
SDIA
—
ST
—
SPIA Data input
C0+
—
AN
—
Comparator positive input
PA3
PAPU
PAWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
SCKA
—
ST
NMOS SPIA Serial Clock
C0-
—
AN
PA4
PAPU
PAWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
—
Comparator negative input
SCSA
—
ST
CMOS SPIA Slave select
TP0_0
TMPC0
ST
CMOS TM0 I/O
PA5
PAPU
PAWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
TP1_0
TMPC0
ST
CMOS TM1 I/O
INT1
—
ST
PA6
PAPU
PAWU
ST
TCK0
—
ST
PA7
PAPU
PAWU
ST
INT0
—
ST
—
External interrupt 0
AN3
ACER0
AN
—
A/D Channel 3
PB0
PXPU
PXWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
SDO
—
—
CMOS SPI Data output
SDA
—
ST
NMOS I2C Data
AN0
ACER0
AN
PB1
PXPU
PXWU
ST
SDI
—
ST
SCL
—
ST
AN1
ACER0
AN
PB2
PXPU
PXWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
SCK
—
ST
CMOS SPI Serial Clock
AN2
ACER0
AN
PB3
PXPU
PXWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
SCS
—
ST
CMOS SPI Slave select
—
External interrupt 1
CMOS General purpose I/O. Register enabled pull-up and wake-up
—
TM0 input
CMOS General purpose I/O. Register enabled pull-up and wake-up
—
A/D Channel 0
CMOS General purpose I/O. Register enabled pull-up and wake-up
—
SPI Data input
NMOS I2C Clock
—
—
A/D Channel 1
A/D Channel 2
18
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
Pin Name
PD0/TP3_1/OSC1
PD1/TP2_1/OSC2
PD2/TCK2
PD4/TCK3/PCK
PE0/VDDIO/VREF
PE1/UBUS/VDD
RES/OCDSCK/ICPCK
UDN/GPIO0/ICPDA
Function
OPT
I/T
PD0
PXPU
PXWU
O/T
Description
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
TP3_1
TMPC1
ST
CMOS TM3 I/O
OSC1
CO
HXT
PD1
PXPU
PXWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
TP2_1
TMPC1
ST
CMOS TM2 I/O
OSC2
CO
—
PD2
PXPU
PXWU
ST
TCK2
—
ST
PD4
PXPU
PXWU
ST
TCK3
TMPC1
ST
PCK
—
—
CMOS Peripheral output clock
PE0
PXPU
PXWU
CO
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
VDDIO
CO
PWR
—
PA external power input
VREF
—
AN
—
ADC reference power input
PE1
—
ST
—
General purpose I/O. Input only
UBUS
—
PWR
—
USB SIE VDD
VDD
—
PWR
—
Power supply
RES
—
ST
—
Reset input
OCDSCK
—
ST
—
OCDS clock, for EV chip only
ICPCK
—
ST
—
ICP clock
—
HXT pin
HXT
HXT pin
CMOS General purpose I/O. Register enabled pull-up and wake-up
—
TM2 input
CMOS General purpose I/O. Register enabled pull-up and wake-up
—
TM3 input
UDN
—
ST
CMOS USB UDN line
GPIO0
—
ST
CMOS General purpose I/O
ICPDA
—
ST
CMOS ICP Data/Address
UDP
—
ST
CMOS USB UDP line
GPIO1
—
ST
CMOS General purpose I/O
VSS
VSS
—
PWR
—
V33O
V33O
—
—
PWR
HVDD
HVDD
—
PWR
—
UDP/GPIO1
Ground
3.3V regulator output
HIRC oscillator Positive Power supply
Note: I/T: Input type;
O/T: Output type
OPT: Optional by configuration option (CO) or register option
PWR: Power;
CO: Configuration option
ST: Schmitt Trigger input;
CMOS: CMOS output;
HXT: High frequency crystal oscillator
LXT: Low frequency crystal oscillator
AN: Analog signal
Where devices exist in more than one package type the table reflects the situation for the package with the largest
number of pins. For this reason not all pins described in the table may exist on all package types.
Rev. 1.40
19
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
HT66FB550
Pin Name
PA0/TCK1/OCDSDA
PA1/SDOA/C0X
PA2/SDIA/C0+
PA3/SCKA/C0-
PA4/SCSA/TP0_0/
C1X
PA5/TP1_0/C1+
PA6/TCK0/C1-
PA7/INT0/AN7
PB0/SDO/SDA/AN0
PB1/SDI/SCL/AN1
PB2/SCK/AN2
PB3/SCS/AN3
Rev. 1.40
Function
OPT
I/T
PA0
PAPU
PAWU
ST
O/T
Description
CMOS General purpose I/O. Register enabled pull-up and wake-up
TCK1
—
ST
OCDSDA
—
ST
CMOS OCDS Data/Address, for EV chip only
—
TM1 input
PA1
PAPU
PAWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
SDOA
—
—
CMOS SPIA Data output
C0X
—
—
CMOS Comparator 0 output
PA2
PAPU
PAWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
SDIA
—
ST
—
SPIA Data input
C0+
—
AN
—
Comparator 0 positive input
PA3
PAPU
PAWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
NMOS SPIA Serial Clock
SCKA
—
ST
C0-
—
AN
PA4
PAPU
PAWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
—
Comparator 0 negative input
SCSA
—
ST
CMOS SPIA Slave select
TP0_0
TMPC0
ST
CMOS TM0 I/O
C1X
—
—
CMOS Comparator 1 output
PA5
PAPU
PAWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
TP1_0
TMPC0
ST
CMOS TM1 I/O
C1+
—
AN
PA6
PAPU
PAWU
ST
TCK0
—
ST
—
TM0 input
C1-
—
AN
—
Comparator 1 negative input
PA7
PAPU
PAWU
ST
—
Comparator 1 positive input
CMOS General purpose I/O. Register enabled pull-up and wake-up
CMOS General purpose I/O. Register enabled pull-up and wake-up
INT0
—
ST
—
External interrupt 0
AN7
ACER0
AN
—
A/D Channel 7
PB0
PXPU
PXWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
SDO
—
—
CMOS SPI Data output
SDA
—
ST
NMOS I2C Data
AN0
ACER0
AN
PB1
PXPU
PXWU
ST
SDI
—
ST
SCL
—
ST
AN1
ACER0
AN
PB2
PXPU
PXWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
CMOS SPI Serial Clock
—
A/D Channel 0
CMOS General purpose I/O. Register enabled pull-up and wake-up
—
SPI Data input
NMOS I2C Clock
—
A/D Channel 1
SCK
—
ST
AN2
ACER0
AN
PB3
PXPU
PXWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
CMOS SPI Slave select
SCS
—
ST
AN3
ACER0
AN
—
—
A/D Channel 2
A/D Channel 3
20
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
Pin Name
PB4/TP0_1/AN4
PB5/PCK/AN5
PB6/INT1/AN6
PB7
PC0/AN8
PC1/AN9
PC2/AN10
PC3/AN11
PC4/AN12
PC5/AN13
PC6/AN14
PC7/AN15
PD0/TP3_1/OSC1
PD1/TP2_1/OSC2
PD2/TCK2
PD3
PD4/TCK3
Rev. 1.40
Function
OPT
I/T
PB4
PXPU
PXWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
TP0_1
TMPC0
ST
CMOS TM0 I/O
AN4
ACER0
AN
PB5
PXPU
PXWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
CMOS Peripheral output clock
PCK
—
—
AN5
ACER0
AN
PB6
PXPU
PXWU
ST
O/T
—
—
Description
A/D Channel 4
A/D Channel 5
CMOS General purpose I/O. Register enabled pull-up and wake-up
INT1
—
ST
—
External interrupt 1
AN6
ACER0
AN
—
A/D Channel 6
PB7
PXPU
PXWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
PC0
PXPU
PXWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
AN8
ACER1
AN
PC1
PXPU
PXWU
ST
AN9
ACER1
AN
PC2
PXPU
PXWU
ST
AN10
ACER1
AN
PC3
PXPU
PXWU
ST
AN11
ACER1
AN
PC4
PXPU
PXWU
ST
AN12
ACER1
AN
PC5
PXPU
PXWU
ST
AN13
ACER1
AN
PC6
PXPU
PXWU
ST
AN14
ACER1
AN
PC7
PXPU
PXWU
ST
AN15
ACER1
AN
PD0
PXPU
PXWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
TP3_1
TMPC1
ST
CMOS TM3 I/O
OSC1
CO
HXT
PD1
PXPU
PXWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
TP2_1
TMPC1
ST
CMOS TM2 I/O
OSC2
CO
—
PD2
PXPU
PXWU
ST
TCK2
—
ST
PD3
PXPU
PXWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
PD4
PXPU
PXWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
TCK3
TMPC1
ST
—
A/D Channel 8
CMOS General purpose I/O. Register enabled pull-up and wake-up
—
A/D Channel 9
CMOS General purpose I/O. Register enabled pull-up and wake-up
—
A/D Channel 10
CMOS General purpose I/O. Register enabled pull-up and wake-up
—
A/D Channel 11
CMOS General purpose I/O. Register enabled pull-up and wake-up
—
A/D Channel 12
CMOS General purpose I/O. Register enabled pull-up and wake-up
—
A/D Channel 13
CMOS General purpose I/O. Register enabled pull-up and wake-up
—
A/D Channel 14
CMOS General purpose I/O. Register enabled pull-up and wake-up
—
—
HXT
A/D Channel 15
HXT pin
HXT pin
CMOS General purpose I/O. Register enabled pull-up and wake-up
—
—
TM2 input
TM3 input
21
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
Pin Name
PD5/TP1_1
PD6/TP3_0
PD7/TP2_0
PE0/VDDIO/VREF
PE1/UBUS
PE2
PE3/XT1
PE4/XT2
PE5
Function
OPT
I/T
PD5
PXPU
PXWU
O/T
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
TP1_1
TMPC0
ST
CMOS TM1 I/O
PD6
PXPU
PXWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
TP3_0
TMPC1
ST
CMOS TM3 I/O
PD7
PXPU
PXWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
TP2_0
TMPC1
ST
CMOS TM2 I/O
PE0
PXPU
PXWU
CO
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
VDDIO
CO
PWR
—
PA external power input
VREF
—
AN
—
ADC reference power input
PE1
—
ST
—
General purpose I/O. Input only
UBUS
—
PWR
—
USB SIE VDD
PE2
PXPU
PXWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
PE3
PXPU
PXWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
XT1
CO
LXT
PE4
PXPU
PXWU
ST
XT2
CO
—
PE5
PXPU
PXWU
ST
—
Description
LXT pin
CMOS General purpose I/O. Register enabled pull-up and wake-up
LXT
LXT pin
CMOS General purpose I/O. Register enabled pull-up and wake-up
RES
—
ST
—
Reset input
OCDSCK
—
ST
—
OCDS clock, for EV chip only
ICPCK
—
ST
—
ICP clock
UDN
—
ST
CMOS USB UDN line
GPIO0
—
ST
CMOS General purpose I/O
ICPDA
—
ST
CMOS ICP Data/Address
UDP
—
ST
CMOS USB UDP line
GPIO1
—
ST
CMOS General purpose I/O
VDD/AVDD
VDD/
AVDD
—
PWR
—
Power supply
VSS/AVSS
VSS/
AVSS
—
PWR
—
Ground
RES/OCDSCK/
ICPCK
UDN/GPIO0/ICPDA
UDP/GPIO1
V33O
V33O
—
—
PWR
HVDD
HVDD
—
PWR
—
3.3V regulator output
HIRC oscillator Positive Power supply.
Note: I/T: Input type;
O/T: Output type
OPT: Optional by configuration option (CO) or register option
PWR: Power;
CO: Configuration option
ST: Schmitt Trigger input;
CMOS: CMOS output;
HXT: High frequency crystal oscillator
LXT: Low frequency crystal oscillator
AN: Analog signal
Where devices exist in more than one package type the table reflects the situation for the package with the largest
number of pins. For this reason not all pins described in the table may exist on all package types.
Rev. 1.40
22
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
HT66FB560
Pin Name
PA0/TCK1/OCDSDA
PA1/SDOA/C0X
PA2/SDIA/C0+
PA3/SCKA/C0-
PA4/SCSA/TP0_0/C1X
PA5/TP1_0/C1+
PA6/TCK0/C1-
PA7/INT0/AN7
PB0/SDO/SDA/AN0
PB1/SDI/SCL/AN1
PB2/SCK/AN2
Rev. 1.40
Function
OPT
I/T
PA0
PAPU
PAWU
ST
O/T
Description
CMOS General purpose I/O. Register enabled pull-up and wake-up
TCK1
—
ST
OCDSDA
—
ST
CMOS OCDS Data/Address, for EV chip only
—
TM1 input
PA1
PAPU
PAWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
SDOA
—
—
CMOS SPIA Data output
C0X
—
—
CMOS Comparator 0 output
PA2
PAPU
PAWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
SDIA
—
ST
—
SPIA Data input
C0+
—
AN
—
Comparator 0 positive input
PA3
PAPU
PAWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
SCKA
—
ST
NMOS SPIA Serial Clock
C0-
—
AN
PA4
PAPU
PAWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
—
Comparator 0 negative input
SCSA
—
ST
CMOS SPIA Slave select
TP0_0
TMPC0
ST
CMOS TM0 I/O
C1X
—
—
CMOS Comparator 1 output
PA5
PAPU
PAWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
TP1_0
TMPC0
ST
CMOS TM1 I/O
C1+
—
AN
PA6
PAPU
PAWU
ST
TCK0
—
ST
—
TM0 input
C1-
—
AN
—
Comparator 1 negative input
PA7
PAPU
PAWU
ST
—
Comparator 1 positive input
CMOS General purpose I/O. Register enabled pull-up and wake-up
CMOS General purpose I/O. Register enabled pull-up and wake-up
INT0
—
ST
—
External interrupt 0
AN7
ACER0
AN
—
A/D Channel 7
PB0
PXPU
PXWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
SDO
—
—
CMOS SPI Data output
SDA
—
ST
NMOS I2C Data
AN0
ACER0
AN
PB1
PXPU
PXWU
ST
SDI
—
ST
SCL
—
ST
AN1
ACER0
AN
PB2
PXPU
PXWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
CMOS SPI Serial Clock
SCK
—
ST
AN2
ACER0
AN
—
A/D Channel 0
CMOS General purpose I/O. Register enabled pull-up and wake-up
—
SPI Data input
NMOS I2C Clock
—
—
A/D Channel 1
A/D Channel 2
23
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
Pin Name
PB3/SCS/AN3
PB4/TP0_1/AN4
PB5/PCK/AN5
PB6/INT1/AN6
PB7
PC0/AN8
PC1/AN9
PC2/AN10
PC3/AN11
PC4/AN12
PC5/AN13
PC6/AN14
PC7/AN15
PD0/TP3_1/OSC1
PD1/TP2_1/OSC2
Rev. 1.40
Function
OPT
I/T
PB3
PXPU
PXWU
O/T
Description
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
CMOS SPI Slave select
SCS
—
ST
AN3
ACER0
AN
PB4
PXPU
PXWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
TP0_1
TMPC0
ST
CMOS TM0 I/O
AN4
ACER0
AN
PB5
PXPU
PXWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
CMOS Peripheral output clock
PCK
—
—
AN5
ACER0
AN
PB6
PXPU
PXWU
ST
—
—
—
A/D Channel 3
A/D Channel 4
A/D Channel 5
CMOS General purpose I/O. Register enabled pull-up and wake-up
INT1
—
ST
—
External interrupt 1
AN6
ACER0
AN
—
A/D Channel 6
PB7
PXPU
PXWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
PC0
PXPU
PXWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
AN8
ACER1
AN
PC1
PXPU
PXWU
ST
AN9
ACER1
AN
PC2
PXPU
PXWU
ST
AN10
ACER1
AN
PC3
PXPU
PXWU
ST
AN11
ACER1
AN
PC4
PXPU
PXWU
ST
AN12
ACER1
AN
PC5
PXPU
PXWU
ST
AN13
ACER1
AN
PC6
PXPU
PXWU
ST
AN14
ACER1
AN
PC7
PXPU
PXWU
ST
AN15
ACER1
AN
PD0
PXPU
PXWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
TP3_1
TMPC1
ST
CMOS TM3 I/O
OSC1
CO
HXT
PD1
PXPU
PXWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
TP2_1
TMPC1
ST
CMOS TM2 I/O
OSC2
CO
—
—
A/D Channel 8
CMOS General purpose I/O. Register enabled pull-up and wake-up
—
A/D Channel 9
CMOS General purpose I/O. Register enabled pull-up and wake-up
—
A/D Channel 10
CMOS General purpose I/O. Register enabled pull-up and wake-up
—
A/D Channel 11
CMOS General purpose I/O. Register enabled pull-up and wake-up.
—
A/D Channel 12
CMOS General purpose I/O. Register enabled pull-up and wake-up
—
A/D Channel 13
CMOS General purpose I/O. Register enabled pull-up and wake-up
—
A/D Channel 14
CMOS General purpose I/O. Register enabled pull-up and wake-up
—
—
HXT
A/D Channel 15
HXT pin
HXT pin
24
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
Pin Name
Function
OPT
I/T
PD2
PXPU
PXWU
ST
TCK2
—
ST
PD3
PXPU
PXWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
PD4
PXPU
PXWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
TCK3
TMPC1
ST
PD5
PXPU
PXWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
TP1_1
TMPC0
ST
CMOS TM1 I/O
PD6
PXPU
PXWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
TP3_0
TMPC1
ST
CMOS TM3 I/O
PD7
PXPU
PXWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
TP2_0
TMPC1
ST
CMOS TM2 I/O
PE0
PXPU
PXWU
CO
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
VDDIO
CO
PWR
—
PA external power input
VREF
—
AN
—
ADC reference power input
PE1
—
ST
—
General purpose I/O. Input only
UBUS
—
PWR
—
USB SIE VDD
PE2
PXPU
PXWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
PE3
PXPU
PXWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
XT1
CO
LXT
PE4
PXPU
PXWU
ST
XT2
CO
—
PE5
PE5
PXPU
PXWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
PF0
PF0
PFPU
PFWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up.
PF1
PF1
PFPU
PFWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
PF2
PF2
PFPU
PFWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
PF3
PF3
PFPU
PFWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
PF4
PF4
PFPU
PFWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
PF5
PF5
PFPU
PFWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
PF6
PF6
PFPU
PFWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
PF7
PF7
PFPU
PFWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
PD2/TCK2
PD3
PD4/TCK3
PD5/TP1_1
PD6/TP3_0
PD7/TP2_0
PE0/VDDIO/VREF
PE1/UBUS
PE2
PE3/XT1
PE4/XT2
RES/OCDSCK/ICPCK
Rev. 1.40
O/T
Description
CMOS General purpose I/O. Register enabled pull-up and wake-up
—
—
—
TM2 input
TM3 input
LXT pin
CMOS General purpose I/O. Register enabled pull-up and wake-up
LXT
LXT pin
RES
—
ST
—
Reset input
OCDSCK
—
ST
—
OCDS clock, for EV chip only
ICPCK
—
ST
—
ICP clock
25
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
Pin Name
Function
OPT
I/T
UDN
—
ST
CMOS USB UDN line
GPIO0
—
ST
CMOS General purpose I/O
ICPDA
—
ST
CMOS
UDP
—
ST
CMOS USB UDP line
GPIO1
—
ST
CMOS General purpose I/O
VDD/AVDD
VDD/
AVDD
—
PWR
—
Power supply
VSS/AVSS
VSS/
AVSS
—
PWR
—
Ground
V33O
V33O
—
—
PWR
HVDD
HVDD
—
PWR
—
UDN/GPIO0/ICPDA
UDP/GPIO1
O/T
Description
ICP Data/Address
3.3V regulator output
HIRC oscillator Positive Power supply
Note: I/T: Input type;
O/T: Output type
OPT: Optional by configuration option (CO) or register option
PWR: Power;
CO: Configuration option
ST: Schmitt Trigger input;
CMOS: CMOS output;
HXT: High frequency crystal oscillator
LXT: Low frequency crystal oscillator
AN: Analog signal
Where devices exist in more than one package type the table reflects the situation for the package with the largest
number of pins. For this reason not all pins described in the table may exist on all package types.
Absolute Maximum Ratings
Supply Voltage.................................................................................................VSS−0.3V to VSS+6.0V
Input Voltage...................................................................................................VSS−0.3V to VDD+0.3V
Storage Temperature.................................................................................................... -50°C to 125°C
Operating Temperature.................................................................................................. -40°C to 85°C
IOH Total...................................................................................................................................-100mA
IOL Total.................................................................................................................................... 150mA
Total Power Dissipation ......................................................................................................... 500mW
Note: These are stress ratings only. Stresses exceeding the range specified under "Absolute Maximum
Ratings" may cause substantial damage to these devices. Functional operation of these devices at
other conditions beyond those listed in the specification is not implied and prolonged exposure to
extreme conditions may affect devices reliability.
Rev. 1.40
26
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
D.C. Characteristics
Ta=25°C
Symbol
VDD1
VDD2
Parameter
Operating Voltage (Crystal OSC)
Operating Voltage
(High Frequency Internal RC OSC)
Test Conditions
Min.
Typ.
fSYS=4MHz
2.2
—
5.5
V
fSYS=6MHz
2.2
—
5.5
V
fSYS=8MHz
2.2
—
5.5
V
fSYS=12MHz
2.7
—
5.5
V
fSYS=16MHz
4.5
—
5.5
V
—
fSYS=12MHz
2.7
—
5.5
V
3V
No load, fH=4MHz,
ADC off, WDT enable
—
0.8
1.5
mA
—
1.8
4.0
mA
No load, fH=6MHz,
ADC off, WDT enable
—
1.0
2.0
mA
—
2.5
5.0
mA
No load, fH=8MHz,
ADC off, WDT enable
—
1.3
3.0
mA
—
3.0
5.5
mA
No load, fH=12MHz,
ADC off, WDT enable
—
2.0
4.0
mA
—
4.0
7.0
mA
No load, fH=12MHz,
ADC off, WDT enable
—
2.0
4.0
mA
—
4.0
7.0
mA
No load, ADC off, WDT enable.
LVR enable
—
40
80
μA
—
70
150
μA
No load, ADC off, WDT enable,
LVR enable, fLIRC=32kHz
—
40
80
μA
—
70
150
μA
No load, fH=12MHz,
ADC off, WDT enable,
USB enable, PLL on, V33O on
—
5.5
10.0
mA
—
11
16
mA
VDD
—
5V
IDD1
Operating Current
(Crystal OSC, fSYS=fH, fS=fSUB=fLXT
or fLIRC)
3V
5V
3V
5V
3V
5V
IDD2
Operating Current (HIRC OSC,
fSYS=fH, fS=fSUB=fLXT or fLIRC)
3V
IDD3
Operating Current
(LXT OSC, fSYS=fL=fLXT, fS=fSUB=fLXT)
3V
5V
5V
IDD4
Operating Current (LIRC OSC,
fSYS=fL=fLIRC, fS=fSUB=fLIRC)
3V
IDD5
Operating Current
(HIRC OSC, fSYS=fH,
fS=fSUB=fLXT or fLIRC)
3V
IDD6
Operating Current
(Crystal OSC, fSYS=fH, fS=fSUB=fLIRC)
5V
5V
Max. Unit
5V
No load, fH=6MHz,
ADC off, WDT enable,
USB enable, PLL on, V33O on
—
10
15
mA
5V
No load, fH=12MHz,
ADC off, WDT enable,
USB enable, PLL on, V33O on
—
11
16
mA
5V
No load, fH=16MHz,
ADC off, WDT enable,
USB enable, PLL on, V33O on
—
12
17
mA
No load, system HALT,
ADC off, WDT enable,
fSYS=oscillator on (FSYSON=1)
—
0.8
1.5
mA
—
1.5
3.0
mA
No load, system HALT,
ADC off, WDT enable,
fSYS=oscillator off (FSYSON=0)
—
1.5
3.0
μA
—
3.0
6.0
μA
No load, system HALT, ADC off,
WDT enable
—
2.0
4.0
μA
—
3.5
7.0
μA
No load, system HALT, ADC off,
WDT enable
—
1.5
3.0
μA
—
3.0
6.0
μA
No load, system HALT, ADC off,
WDT disable
—
0.1
1.0
μA
—
0.3
2.0
μA
ISTB1
Standby Current (Idle 1)
(Crystal OSC, fSYS=fH,
fS=fSUB=fLXT or fLIRC)
ISTB2
Standby Current (Idle 0)
(Crystal or HIRC OSC, fSYS=off,
fS=fSUB=fLXT or fLIRC)
ISTB3
Standby Current (Idle 0)
(LXT OSC, fSYS=off, fS=fSUB=fLXT)
3V
ISTB4
Standby Current (Idle)
(LIRC OSC, fSYS=off, fS=fSUB=fLIRC)
3V
ISTB5
Standby Current (Sleep 0)
(Crystal or HIRC OSC, fSYS=off,
fS=fSUB=fLXT or fLIRC)
3V
Rev. 1.40
Conditions
3V
5V
3V
5V
5V
5V
5V
27
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
Symbol
Parameter
ISTB6
Standby Current (Sleep 1)
(Crystal or HIRC OSC, fSYS=off,
fS=fSUB=fLXT or fLIRC)
ISTB7
Standby Current (Sleep 0)
(Crystal or HIRC OSC, fSYS=off,
fS=fSUB=fLXT or fLIRC)
ISUS1
Suspend Current (Sleep 0)
(Crystal or HIRC OSC, fSYS=off,
fS=fSUB=fLXT or fLIRC)
Test Conditions
VDD
3V
No load, system HALT, ADC off,
WDT enable
Min.
Typ.
Max. Unit
—
1.5
3.0
μA
—
3.0
6.0
μA
—
No load, system HALT, ADC off,
WDT disable, LVR enable and
LVDEN=1
—
60
90
μA
5V
No load, system HALT, ADC off,
WDT disable, USB transceiver,
3.3V Regulator on and clr
suspend2 (UCC.4)
—
360
420
μA
ISUS2
Suspend Current (Sleep 0)
(Crystal or HIRC OSC, fSYS=off,
fS=fSUB=fLXT or fLIRC)
5V
No load, system HALT, ADC off,
WDT disable, USB transceiver,
3.3V Regulator on and set
suspend2 (UCC.4)
—
240
320
μA
VIL1
Input Low Voltage for I/O Ports,
TCK and INT
—
—
0
—
0.2VDD
V
VIH1
Input High Voltage for I/O Ports,
TCK and INT
—
—
0.8VDD
—
VDD
V
VIL2
Input Low Voltage (RES)
—
—
0
—
0.4VDD
V
VIH2
Input High Voltage (RES)
—
—
0.9VDD
—
VDD
V
—
mA
IOL
IOH
I/O Port Sink Current
I/O Port, Source Current
VV33O
3.3V regulator output
RUDP
Pull-high Resistance of UDP to
V33O
RPH
Pull-high Resistance of I/O Ports
RPL
Pull-low Resistance of UBUS pin
5V
Conditions
3V
VOL=0.1VDD (PAOI or PXOI=1)
4
8
5V
VOL=0.1VDD (PAOI or PXOI=1)
10
20
—
mA
5V
VOL=0.1VDD (PAOI or PXOI=0)
2
4
—
mA
3V
VOH=0.9VDD (PAOI or PXOI=1)
-2
-4
—
mA
5V
VOH=0.9VDD (PAOI or PXOI=1)
-5
-10
—
mA
5V
VOH=0.9VDD (PAOI or PXOI=0)
-2
-4
—
mA
5V
IV33O=70mA
3.0
3.3
3.6
V
-5%
1.5
+5%
kΩ
3.3V
—
3V
—
20
60
100
kΩ
5V
—
10
30
50
kΩ
0.5
1
1.5
MΩ
5V
SUSP2=1, RUBUS=0
Note: The LXT oscillator is not available in the HT66FB542 device.
Rev. 1.40
28
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
A.C. Characteristics
Ta=25°C
Symbol
Parameter
VDD
Condition
Min.
Typ.
Max.
Unit
2
—
4
MHz
2
—
6
MHz
2
—
8
MHz
2.7~5.5V
2
—
12
MHz
4.5~5.5V
2
—
16
MHz
2.2~5.5V Non-USB mode, Ta=25°C
-3%
12
+3%
MHz
3.0~5.5V Non-USB mode, Ta=-40~85°C
-6%
12
+6%
MHz
2.2~5.5V Non-USB mode, Ta=-40~85°C
-10%
12
+10%
MHz
2.2~5.5V
2.2~5.5V
fSYS1
System Clock (Crystal OSC)
fSYS2
System Clock (HIRC OSC)
fSYS3
System Clock (32768 Crystal)
2.2~5.5V
—
3.3~5.5V USB mode
fLIRC
System Clock (32K RC)
—
5V
—
Ta=25°C
2.2~5.5V Ta=-40°C to 85°C
2.2~5.5V
fTIMER
Timer I/P Frequency (TCKn)
2.7~5.5V
—
4.5~5.5V
-0.25%
12
—
32768
+0.25% MHz
—
Hz
-10%
32
+10%
kHz
-50%
32
+60%
kHz
2
—
8
MHz
2
—
12
MHz
2
—
16
MHz
tBGS
VBG Turn on Stable Time
—
—
10
—
—
ms
tTIMER
TCKn Input Pin Minimum
Pulse Width
—
—
0.3
—
—
μs
tRES
External Reset Minimum Low
Pulse Width
—
—
10
—
—
μs
tINT
Interrupt Minimum Pulse Width
—
—
10
—
—
μs
—
fSYS=HXT or LXT (Slow Mode
→ Normal Mode(HXT), Normal
Mode → Slow Mode(LXT))
1024
—
—
tSYS
—
fSYS=HXT (Wake-up from HALT,
fSYS off at HALT state)
1024
—
—
tSYS
—
fSYS=HIRC
1024
—
—
tSYS
—
fSYS=LIRC
2
—
—
tSYS
tSST
tRSTD
System Start-up Timer Period
(Wake-up from HALT,
fSYS off at HALT state,
Slow Mode → Normal Mode,
Normal Mode → Slow Mode)
System Start-up Timer Period
(Wake-up from HALT, fSYS on
at HALT state)
—
—
2
—
—
tSYS
System Start-up Timer Period
(Reset)
—
—
1024
—
—
tSYS
System Reset Delay Time
(Power On Reset)
—
—
25
50
100
ms
System Reset Delay Time
(Any Reset except Power On
Reset)
—
—
8.3
16.7
33.3
ms
Note: The LXT oscillator is not available in the HT66FB542 device.
Rev. 1.40
29
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
LVD & LVR Electrical Characteristics
Ta=25°C
Symbol
Parameter
Test Conditions
VDD
Conditions
VLVR1
LVR Enable, 2.10V option
VLVR2
LVR Enable, 2.55V option
VLVR3
Low Voltage Reset Voltage
—
LVR Enable, 3.15V option
Min.
Typ. Max. Unit
2.1
V
-5%
×Typ.
2.55 +5%
3.15 ×Typ.
V
V
VLVR4
LVR Enable, 3.80V option
3.8
V
VLVD1
LVDEN=1, VLVD=2.0V
2.0
V
VLVD2
LVDEN=1, VLVD=2.2V
2.2
V
VLVD3
LVDEN=1, VLVD=2.4V
2.4
V
VLVD4
VLVD5
Low Voltage Detector Voltage
—
LVDEN=1, VLVD=2.7V
LVDEN=1, VLVD=3.0V
-5%
×Typ.
2.7
3.0
+5%
×Typ.
V
V
VLVD6
LVDEN=1, VLVD=3.3V
3.3
V
VLVD7
LVDEN=1, VLVD=3.6V
3.6
V
VLVD8
LVDEN=1, VLVD=4.0V
4.0
V
1.25 +3%
V
μA
VBG
Reference Voltage with Buffer Voltage
—
—
-3%
IBG
Additional Power Consumption if
Reference with Buffer is Used
—
—
—
200
300
ILVD
Additional Power Consumption if
LVD/LVR is Used
3V LVD disable → LVD enable
5V (LVR enable)
—
30
45
μA
—
60
90
μA
tLVR
Low Voltage Width to Reset
—
—
120
240
480
us
tLVD
Low Voltage Width to Interrupt
—
—
20
45
90
μs
tSRESET
Software Reset Width to Reset
—
—
45
90
120
μs
—
For LVR enable, LVD off → on
15
—
—
μs
tLVDS
Rev. 1.40
LVDO Stable Time
30
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
ADC Electrical Characteristics
Ta=25°C
Symbol
Parameter
VDD
AVDD
Analog Operating Voltage
—
VADI
A/D Input Voltage
—
Condition
VREF=AVDD
—
Min. Typ.
Max.
Unit
2.7
—
5.5
V
0
—
VREF
V
V
—
AVDD=3V
2.0
—
AVDD
—
AVDD=5V
2.0
—
AVDD
V
16
—
20
tAD
VREF
ADC Input Reference Voltage Range
tADC
A/D Conversion Time
2.7~5.5V 12 bit ADC
tADCK
A/D Converter Clock Period
2.7~5.5V
—
0.5
—
10
μs
tON2ST
ADC on to ADC Start
2.7~5.5V
—
4
—
—
μs
DNL
Differential Non-linearity
3V/5V
VREF=AVDD
-3
—
+3
LSB
INL
Integral Non-linearity
3V/5V
VREF=AVDD
-4
—
+4
LSB
3V
No load (tAD=0.5μs )
—
1.0
2.0
mA
5V
No load (tAD=0.5μs )
—
1.5
3.0
mA
IADC
only ADC Enable, Others Disable
Comparator Electrical Characteristics
Ta=25°C
Symbol
Parameter
VDD
Condition
Min. Typ.
Max.
Unit
VCMP
Comparator Operating Voltage
—
—
2.2
—
5.5
V
ICMP
Comparator Operating Current
5V
—
—
—
200
μA
ICSTB
Comparator Power Down Current
5V Comparator disable
—
—
0.1
μA
VCMPOS
Comparator Input Offset Voltage
5V
—
-10
—
+10
mV
VHYS
Hysteresis Width
5V
20
40
60
mV
VCM
Comparator Common Mode Voltage Range
—
—
VSS
—
VDD-1.4V
V
AOL
Comparator Open Loop Gain
—
—
60
80
—
dB
With 100mV overdrive(Note)
—
200
400
ns
tPD
3V
Comparator Response Time
5V
Note: Measured with comparator one input pin at VCM=(VDD-1.4)/2 while the other pin input transition from VSS to
(VCM+100mV) or from VDD to (VCM-100mV).
Power on Reset (AC+DC) Electrical Characteristics
Ta=25°C
VDD
Condition
Min.
Typ.
Max.
Unit
VPOR
Symbol
VDD Start Voltage to Ensure Power-on Reset
Parameter
—
—
—
—
100
mV
RRVDD
VDD Rise Rate to ensure Power-on Reset
—
—
0.035
—
—
V/ms
tPOR
Minimum Time for VDD Stays at VPOR to Ensure
—
Power-on Reset
—
1
—
—
ms
Rev. 1.40
31
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
System Architecture
A key factor in the high-performance features of the Holtek range of microcontrollers is attributed
to their internal system architecture. The range of devices take advantage of the usual features found
within RISC microcontrollers providing increased speed of operation and enhanced performance.
The pipelining scheme is implemented in such a way that instruction fetching and instruction
execution are overlapped, hence instructions are effectively executed in one cycle, with the
exception of branch or call instructions. An 8-bit wide ALU is used in practically all instruction set
operations, which carries out arithmetic operations, logic operations, rotation, increment, decrement,
branch decisions, etc. The internal data path is simplified by moving data through the Accumulator
and the ALU. Certain internal registers are implemented in the Data Memory and can be directly
or indirectly addressed. The simple addressing methods of these registers along with additional
architectural features ensure that a minimum of external components is required to provide a
functional I/O and A/D control system with maximum reliability and flexibility. This makes these
devices suitable for low-cost, high-volume production for controller applications.
Clocking and Pipelining
The main system clock, derived from either a HXT, LXT, HIRC or LIRC oscillator is
subdivided into four internally generated non-overlapping clocks, T1~T4. Note that the LXT
oscillator is not available in the HT66FB542 device. The Program Counter is incremented at the
beginning of the T1 clock during which time a new instruction is fetched. The remaining T2~T4
clocks carry out the decoding and execution functions. In this way, one T1~T4 clock cycle forms
one instruction cycle. Although the fetching and execution of instructions takes place in consecutive
instruction cycles, the pipelining structure of the microcontroller ensures that instructions are
effectively executed in one instruction cycle. The exception to this are instructions where the
contents of the Program Counter are changed, such as subroutine calls or jumps, in which case the
instruction will take one more instruction cycle to execute.
For instructions involving branches, such as jump or call instructions, two machine cycles are
required to complete instruction execution. An extra cycle is required as the program takes one
cycle to first obtain the actual jump or call address and then another cycle to actually execute the
branch. The requirement for this extra cycle should be taken into account by programmers in timing
sensitive applications.


   
   
System Clocking and Pipelining
Rev. 1.40
32
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
  
    
 Instruction Fetching
Program Counter
During program execution, the Program Counter is used to keep track of the address of the next
instruction to be executed. It is automatically incremented by one each time an instruction is
executed except for instructions, such as "JMP" or "CALL" that demand a jump to a non-consecutive
Program Memory address. As the device memory capacity is greater than 8K words, the Program
Memory address may be located in a certain program memory bank which is selected by the
program memory bank pointer bit, PMBP0. Only the lower 8 bits, known as the Program Counter
Low Register, are directly addressable by the application program.
When executing instructions requiring jumps to non-consecutive addresses such as a jump
instruction, a subroutine call, interrupt or reset, etc., the microcontroller manages program control
by loading the required address into the Program Counter. For conditional skip instructions, once
the condition has been met, the next instruction, which has already been fetched during the present
instruction execution, is discarded and a dummy cycle takes its place while the correct instruction is
obtained.
Device
HT66FB540
Program Counter
Program Counter High Byte
PCL Register
PC11~PC8
HT66FB542
PC11~PC8
HT66FB550
PC12~PC8
HT66FB560
PMBP0, PC12~PC8
PCL7~PCL0
Program Counter
The lower byte of the Program Counter, known as the Program Counter Low register or PCL, is
available for program control and is a readable and writeable register. By transferring data directly
into this register, a short program jump can be executed directly; however, as only this low byte
is available for manipulation, the jumps are limited to the present page of memory, which is 256
locations. When such program jumps are executed it should also be noted that a dummy cycle
will be inserted. Manipulating the PCL register may cause program branching, so an extra cycle is
needed to pre-fetch.
Rev. 1.40
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September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
Stack
This is a special part of the memory which is used to save the contents of the Program Counter only.
The stack has multiple levels depending upon these devices and is neither part of the data nor part
of the program space, and is neither readable nor writeable. The activated level is indexed by the
Stack Pointer, and is neither readable nor writeable. At a subroutine call or interrupt acknowledge
signal, the contents of the Program Counter are pushed onto the stack. At the end of a subroutine or
an interrupt routine, signaled by a return instruction, RET or RETI, the Program Counter is restored
to its previous value from the stack. After a device reset, the Stack Pointer will point to the top of the
stack.
If the stack is full and an enabled interrupt takes place, the interrupt request flag will be recorded but
the acknowledge signal will be inhibited. When the Stack Pointer is decremented, by RET or RETI,
the interrupt will be serviced. This feature prevents stack overflow allowing the programmer to use
the structure more easily. However, when the stack is full, a CALL subroutine instruction can still
be executed which will result in a stack overflow. Precautions should be taken to avoid such cases
which might cause unpredictable program branching.
If the stack is overflow, the first Program Counter save in the stack will be lost.
P ro g ra m
T o p o f S ta c k
C o u n te r
S ta c k L e v e l 1
S ta c k L e v e l 2
S ta c k
P o in te r
S ta c k L e v e l 3
B o tto m
o f S ta c k
P ro g ra m
M e m o ry
S ta c k L e v e l N
Device
Stack Levels
HT66FB540/HT66FB542/HT66FB550
8
HT66FB560
12
Arithmetic and Logic Unit – ALU
The arithmetic-logic unit or ALU is a critical area of the microcontroller that carries out arithmetic
and logic operations of the instruction set. Connected to the main microcontroller data bus, the ALU
receives related instruction codes and performs the required arithmetic or logical operations after
which the result will be placed in the specified register. As these ALU calculation or operations may
result in carry, borrow or other status changes, the status register will be correspondingly updated to
reflect these changes. The ALU supports the following functions:
• Arithmetic operations: ADD, ADDM, ADC, ADCM, SUB, SUBM, SBC, SBCM, DAA
• Logic operations: AND, OR, XOR, ANDM, ORM, XORM, CPL, CPLA
• Rotation RRA, RR, RRCA, RRC, RLA, RL, RLCA, RLC
• Increment and Decrement INCA, INC, DECA, DEC
• Branch decision, JMP, SZ, SZA, SNZ, SIZ, SDZ, SIZA, SDZA, CALL, RET, RETI
Rev. 1.40
34
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
Flash Program Memory
The Program Memory is the location where the user code or program is stored. For these devices
series the Program Memory are Flash type, which means it can be programmed and re-programmed
a large number of times, allowing the user the convenience of code modification on the same
device. By using the appropriate programming tools, these Flash devices offer users the flexibility to
conveniently debug and develop their applications while also offering a means of field programming
and updating.
Structure
The Program Memory has a capacity of 4K×16 bits to 16K×16 bits. The Program Memory is
addressed by the Program Counter and also contains data, table information and interrupt entries.
Table data, which can be setup in any location within the Program Memory, is addressed by a
separate table pointer register.
Device
Capacity
Banks
HT66FB540/HT66FB542
4K×16
0
HT66FB550
8K×16
0
HT66FB560
16K×16
0, 1
The HT66FB560 has its Program Memory divided into two Banks, Bank 0 and Bank 1. The required
Bank is selected using Bit 5 of the BP Register.
Special Vectors
Within the Program Memory, certain locations are reserved for the reset and interrupts. The location
000H is reserved for use by these devices reset for program initialisation. After a device reset is
initiated, the program will jump to this location and begin execution.
R e s e t
R e s e t
R e s e t
0 0 3 8 H
In te rru p t
V e c to r
In te rru p t
V e c to r
In te rru p t
V e c to r
0 F F F H
1 6 b its
0 0 0 0 H
0 0 0 4 H
B a n k 0
1 F F F H
1 6 b its
1 6 b its
2 0 0 0 H
B a n k 1
3 F F F H
Program Memory Structure
Rev. 1.40
35
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
Look-up Table
Any location within the Program Memory can be defined as a look-up table where programmers can
store fixed data. To use the look-up table, the table pointer must first be setup by placing the address
of the look up data to be retrieved in the table pointer register, TBLP and TBHP. These registers
define the total address of the look-up table.
After setting up the table pointer, the table data can be retrieved from the Program Memory using
the "TABRD [m]" instructions, respectively. When the instruction is executed, the lower order table
byte from the Program Memory will be transferred to the user defined Data Memory register [m]
as specified in the instruction. The higher order table data byte from the Program Memory will be
transferred to the TBLH special register. Any unused bits in this transferred higher order byte will be
read as "0".
The accompanying diagram illustrates the addressing data flow of the look-up table.
A d d re s s
T B H P R e g is te r
T B L P R e g is te r
D a ta
1 6 b its
R e g is te r T B L H
U s e r S e le c te d
R e g is te r
H ig h B y te
L o w B y te
Table Program Example
The following example shows how the table pointer and table data is defined and retrieved from the
microcontroller. This example uses raw table data located in the Program Memory which is stored
there using the ORG statement. The value at this ORG statement is "1F00H" which refers to the
start address of the last page within the 8K Program Memory of the HT66FB550. The table pointer
is setup here to have an initial value of "06H". This will ensure that the first data read from the data
table will be at the Program Memory address "1F06H" or 6 locations after the start of the last page.
Note that the value for the table pointer is referenced to the first address of the present page if the
"TABRD [m]" instruction is being used. The high byte of the table data which in this case is equal
to zero will be transferred to the TBLH register automatically when the "TABRD [m]" instruction is
executed.
Because the TBLH register is a read-only register and cannot be restored, care should be taken
to ensure its protection if both the main routine and Interrupt Service Routine use table read
instructions. If using the table read instructions, the Interrupt Service Routines may change the
value of the TBLH and subsequently cause errors if used again by the main routine. As a rule it is
recommended that simultaneous use of the table read instructions should be avoided. However, in
situations where simultaneous use cannot be avoided, the interrupts should be disabled prior to the
execution of any main routine table-read instructions. Note that all table related instructions require
two instruction cycles to complete their operation.
Rev. 1.40
36
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
Table Read Program Example
tempreg1 db ? ; temporary register #1
tempreg2 db ? ; temporary register #2
:
:
mov a,06h ; initialise low table pointer - note that this address is referenced
mov tblp,a ; to the last page or the page that tbhp pointed
mov a,1Fh ; initialise high table pointer
mov tbhp,a
:
:
tabrd tempreg1 ; transfers value in table referenced by table pointer data at program
; memory address "1F06H" transferred to tempreg1 and TBLH
dec tblp ; reduce value of table pointer by one
tabrd tempreg2 ; transfers value in table referenced by table pointer
; data at program memory address "1F05H" transferred to
; tempreg2 and TBLH in this example the data "1AH" is
; transferred to tempreg1 and data "0FH" to register tempreg2
:
:
org 1F00h ; sets initial address of program memory
dc 00Ah, 00Bh, 00Ch, 00Dh, 00Eh, 00Fh, 01Ah, 01Bh
:
:
In System Programming – ISP
The provision of Flash type Program Memory provides the user with a means of convenient and easy
upgrades and modifications to their programs on the same device. As an additional convenience,
Holtek has provided a means of programming the microcontroller in-system using a two-line
USB interface. This provides manufacturers with the possibility of manufacturing their circuit
boards complete with a programmed or un-programmed microcontroller, and then programming
or upgrading the program at a later stage. This enables product manufacturers to easily keep their
manufactured products supplied with the latest program releases without removal and re-insertion of
the devices.
The Program Memory can be programmed serially in-system using the USB interface, namely using
the UDN and UDP pins. The power is supplied by the UBUS pin. The technical details regarding the
in-system programming of these devices are beyond the scope of this document and will be supplied
in supplementary literature. The Flash Program Memory Read/Write function is implemented using
a series of registers.
Flash Memory Read/Write Page Size
There are two page sizes, 32 words or 64 words, assigned for various Flash memory size. When
the Flash memory, larger than 8K bytes, is selected, the 64 word page size is assigned per page and
buffer. Otherwise, the page and buffer size are assigned as 32 words.
The following diagram illustrates the Read/Write page and buffer assignment. The write buffer is
controlled by the CLWB bit in the FRCR register. The CLWB bit can be set high to enable the Clear
Write Buffer procedure, as the procedure is finished, this bit will be cleared to low by hardware.
Rev. 1.40
37
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
The Write Buffer is filled when the FWEN bit is set to high, when this bit is set high, the data in the
Write buffer will be written to the Flash ROM, the FWT bit is used to indicate the writing procedure.
Setting this bit high and check if the write procedure is finished, this bit will be cleared by hardware.
The Read Byte can be assigned by the address. The FRDEN is used to enable the read function and
the FRD is used to indicate the reading procedure. When the reading procedure is finished, this bit
will be cleared by hardware.
Device
Page size (words)
Write Buffer(Words)
HT66FB540/HT66FB542(4K×16)
32
32
HT66FB550(8K×16)
32
32
HT66FB560(16K×16)
64
64
Flash Me�o�y
W�ite Buffe�
FARH
FARL
FD0H
FD0L
CLWB
Write one word to FD0L/FD0H
Flash Me�o�y
FARH
FARL
FD0H
FD0L
Read one word to FD0L/FD0H
Note: 1. Writing a data into high byte, which means the High/Low byte Data is written into Write
Buffer, will cause the Flash memory address increased by one automatically and the new
address will be loaded to the FARH and FARL registers. However, the user can also fill the
new address by filling the data into FARH and FARL registers in the same page, then the
data will be written into the corresponding address.
2. If the address already reached the boundary of the flash memory, such as 11111b of the 32
words or 111111b of the 64 words. At this moment, the address will not be increased and
the address will stop at the last address of that page and the writing data is invalid.
3. At this point, the user has to set a new address again to fill a new data.
4. If the data is writing using the write buffer, the write buffer will be cleared by hardware
automatically after the write procedure is ready in 2ms.
5. Fisrt time use the Write buffer or renew the data in the Write buffer, the user can use to
Clear buffer bit (CLWB) to clear write buffer.
Rev. 1.40
38
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
ISP Bootloader
The devices provide the ISP Bootloader function to upgrade the software in the Flash memory.
The user can select to use the ISP Bootloader application software provided by Holtek IDE tool
or to create his own Bootloader software. When the Holtek Bootloader software is selected, that
will occupy 0.5K words area in the Flash memory. The accompanying diagram illustrates the Flash
memory structure with Holtek Bootloader software.
HT66FB540/
HT66FB542
HT66FB550
Bootloade�
0D00H
0DFFH
Bootloade�
000H
0000H
HT66FB560
Bootloade�
0000H
Last Page
Bank 0
1D00H
1DFFH
Last Page
1FFFH
Bank 1
3D00H
3DFFH
Last Page
Flash Memory Structure with Bootloader Software
Flash Program Memory Registers
There are two address registers, four 16-bit data registers and two control registers. The address and
data high byte registers together with the control registers are located in Bank1 while other registers
are located in Bank 0. Read and Write operations to the Flash memory are carried out in 16-bit data
operations using the address and data registers and the control register. Several registers control the
overall operation of the internal Flash Program Memory. The address registers are named FARL
and FARH, the data registers are named FDnL and FDnH, and the control registers are named FCR
and FRCR. As the FARL and FDnL registers are located in Bank 0, they can be directly accessed in
the same was as any other Special Function Register. The FARH, FDnH, FCR and FRCR registers
however, being located in Bank1, cannot be addressed directly and can only be read from or written
to indirectly using the MP1 Memory Pointer and Indirect Addressing Register, IAR1.
Rev. 1.40
39
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
Program Memory Register List
• HT66FB540/HT66FB542
Name
Bit
7
6
5
4
3
2
1
0
FARL
D7
D6
D5
D4
D3
D2
D1
D0
FARH
—
—
—
—
D11
D10
D9
D8
FD0L
D7
D6
D5
D4
D3
D2
D1
D0
FD0H
D15
D14
D13
D12
D11
D10
D9
D8
FD1L
D7
D6
D5
D4
D3
D2
D1
D0
FD1H
D15
D14
D13
D12
D11
D10
D9
D8
FD2L
D7
D6
D5
D4
D3
D2
D1
D0
FD2H
D15
D14
D13
D12
D11
D10
D9
D8
FD3L
D7
D6
D5
D4
D3
D2
D1
D0
FD3H
D15
D14
D13
D12
D11
D10
D9
D8
FCR
CFWEN
FMOD2
FMOD1
FMOD0
BWT
FWT
FRDEN
FRD
—
—
—
FSWRST
—
—
—
CLWB
7
6
5
4
3
2
1
0
FARL
D7
D6
D5
D4
D3
D2
D1
D0
FARH
—
—
—
D12
D11
D10
D9
D8
FRCR
• HT66FB550
Name
Bit
FD0L
D7
D6
D5
D4
D3
D2
D1
D0
FD0H
D15
D14
D13
D12
D11
D10
D9
D8
FD1L
D7
D6
D5
D4
D3
D2
D1
D0
FD1H
D15
D14
D13
D12
D11
D10
D9
D8
FD2L
D7
D6
D5
D4
D3
D2
D1
D0
FD2H
D15
D14
D13
D12
D11
D10
D9
D8
FD3L
D7
D6
D5
D4
D3
D2
D1
D0
FD3H
D15
D14
D13
D12
D11
D10
D9
D8
FCR
CFWEN
FMOD2
FMOD1
FMOD0
BWT
FWT
FRDEN
FRD
—
—
—
FSWRST
—
—
—
CLWB
FRCR
• HT66FB560
Name
FARL
7
6
5
4
3
2
1
0
D7
D6
D5
D4
D3
D2
D1
D0
FARH
—
—
D13
D12
D11
D10
D9
D8
FD0L
D7
D6
D5
D4
D3
D2
D1
D0
FD0H
D15
D14
D13
D12
D11
D10
D9
D8
FD1L
D7
D6
D5
D4
D3
D2
D1
D0
FD1H
D15
D14
D13
D12
D11
D10
D9
D8
FD2L
D7
D6
D5
D4
D3
D2
D1
D0
FD2H
D15
D14
D13
D12
D11
D10
D9
D8
FD3L
D7
D6
D5
D4
D3
D2
D1
D0
FD3H
D15
D14
D13
D12
D11
D10
D9
D8
FCR
CFWEN
FMOD2
FMOD1
FMOD0
BWT
FWT
FRDEN
FRD
—
—
—
FSWRST
—
—
—
CLWB
FRCR
Rev. 1.40
Bit
40
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
FARL Register
Bit
7
6
5
4
3
2
1
0
Name
D7
D6
D5
D4
D3
D2
D1
D0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
x
x
x
x
x
x
x
x
"x" unknown
Bit 7~0
Flash Program Memory address
Flash Program Memory address bit 7~bit 0
FARH Register
• HT66FB540/HT66FB542
Bit
7
6
5
4
3
2
1
0
Name
—
—
—
—
D11
D10
D9
D8
R/W
—
—
—
—
R/W
R/W
R/W
R/W
POR
—
—
—
—
x
x
x
x
"x" unknown
Bit 7~4
Reserved, cannot be used
Bit 3~0
Flash Program Memory address
Flash Program Memory address bit 11~bit 8
• HT66FB550
Bit
7
6
5
4
3
2
1
0
Name
—
—
—
D12
D11
D10
D9
D8
R/W
—
—
—
R/W
R/W
R/W
R/W
R/W
POR
—
—
—
x
x
x
x
x
"x" unknown
Bit 7~5
Reserved, cannot be used
Bit 4~0
Flash Program Memory address
Flash Program Memory address bit 12~bit 8
• HT66FB560
Bit
7
6
5
4
3
2
1
0
Name
—
—
D13
D12
D11
D10
D9
D8
R/W
—
—
R/W
R/W
R/W
R/W
R/W
R/W
POR
—
—
x
x
x
x
x
x
"x" unknown
Rev. 1.40
Bit 7~6
Reserved, cannot be use
Bit 5~0
Flash Program Memory address
Flash Program Memory address bit 13~bit 8
41
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
FCR Register
Bit
7
6
5
4
3
2
1
0
Name
CFWEN
FMOD2
FMOD1
FMOD0
BWT
FWT
FRDEN
FRD
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
0
0
0
0
0
0
0
Bit 7CFWEN: Flash ROM Write Enable bit, FWEN, control bit
0: Disable
1: Unimplemented
This bit is used to control the FWEN bit enable or disable. When this bit is cleared to
low by software, the Flash memory write enable control bit, FWEN, will be cleared to
low as well. It’s ineffective to set this bit to high. The user can check this bit to confirm
the FWEN status.
Bit 6~4FMOD2~FMOD0: Flash Program memory operating mode control bits
000: Write memory mode
001: Page erase mode
010: Reserved
011: Read memory mode
100: Reserved
101: Reserved
110: FWEN (Flash memory write enable) bit control mode
111: Reserved
Bit 3BWT: Mode change control
0: Mode change cycle has finished
1: Activate a mode change cycle
This bit will be automatically reset to zero by the hardware after the mode change
cycle has finished.
Bit 2FWT: Flash memory Write Control
0: Write cycle has finished
1: Activate a write cycle
This is the Flash memory Write Control Bit and when set high by the application
program will activate a write cycle. This bit will be automatically reset to zero by the
hardware after the write cycle has finished.
Bit 1FRDEN: Flash Memory Read Enable
0: Disable
1: Enable
This is the Flash memory Read Enable Bit which must be set high before Flash
memory read operations are carried out. Clearing this bit to zero will inhibit Flash
memory read operations.
Bit 0FRD: Flash memory Read Control
0: Read cycle has finished
1: Activate a read cycle
This is the Flash memory Read Control Bit and when set high by the application
program will activate a read cycle. This bit will be automatically reset to zero by the
hardware after the read cycle has finished. Setting this bit high will have no effect if
the RDEN has not first been set high.
Note: The FWT, FRDEN and FRD can not be set to "1" at the same time with a single instruction.
Rev. 1.40
42
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
FRCR Register
Bit
7
6
5
4
3
2
1
0
Name
—
—
—
FSWRST
—
—
—
CLWB
R/W
—
—
—
R/W
—
—
—
R/W
POR
—
—
—
0
—
—
—
0
Bit 7~5
Unimplemented, read as "0"
Bit 4FSWRST: control bit
Must be to 0
Bit 3~1
Unimplemented, read as "0"
Bit 0CLWB: Flash Program memory Write buffer clear control bit
0: Do not initiate clear Write Buffer or clear Write Buffer process is completed
1: Initiate clear Write Buffer process
This bit is used to control the Flash Program memory clear Write buffer process. It
will be set by software and cleared by hardware.
In Application Programming – IAP
Offering users the convenience of Flash Memory multi-programming features, the series of devices
not only provide an ISP function, but also an additional IAP function. The convenience of the IAP
function is that it can execute the updated program procedure using its internal firmware, without
requiring an external Program Writer or PC. In addition, the IAP interface can also be any type of
communication protocol, such as UART or USB, using I/O pins. Designers can assign I/O pins
to communicate with the external memory device, including the updated program. Regarding the
internal firmware, the user can select versions provided by HOLTEK or create their own. The
following section illustrates the procedures regarding how to implement IAP firmware.
Enable Flash Write Control Procedure
The first procedure to implement the IAP firmware is to enable the Flash Write control which
includes the following steps.
• Write data "110" to the FMOD [2:0] bits in the FCR register to enable the Flash write control bit, FWEN.
• Set the BWT bit in the FCR register to "1".
• These devices will start a 1ms counter. The user should write the correct data pattern into the
Flash data registers, namely FD1L~FD3L and FD1H~FD3H, during this period of time.
• Once the 1ms counter has overflowed or if the written pattern is incorrect, the enable Flash write
control procedure will be invalid and the user should repeat the above procedure.
• No matter whether the procedure is valid or not, the devices will clear the BWT bit automatically.
• The enable Flash write pattern data is (00H, 04H, 0DH, 09H, C3H, 40H) and it should be written
into the Flash data registers.
• Once the Flash write operation is enabled, the user can update the Flash memory using the Flash
control registers.
• To disable the Flash write procedure, the user can only clear the CFWEN bit in the FCR register.
There is no need to execute the above procedure.
Rev. 1.40
43
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
�et FWEN
FMOD �~0=110 : �et FWEN �it
BWT =1�Ha�dwa�e set a counte�
W�tie the following �atte�n to Flash Data �egiste�
FD 1L = 00h � FD 1H = 04h
FD �L =0dh � FD �H = 09h
FD 3L =C3h � FD 3H = 40h
NO
Is counte�
ove�flow?
BWT=0?
YE�
Is �atte�n is
co��ect ?
NO
YE�
CFWEN=1
.
�et FWEN �it success
CFWEN=0
�et FWEN �it fail
END
Rev. 1.40
44
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
Flash Memory Write and Read Procedures
The following flow charts illustrate the Write and Read Flash memory procedures.
Write Flash
ROM
Set FWEN procedure
Page Erase
FARH=xxh, FARL=xxh
FMOD 2~0=001
FWT=1
NO
FWT=0 ?
YES
Write
FMOD 2~0=000
Write data to Write Buffer
[(ROM ≤ 8K→1~32 Words data) or
(ROM > 8K→1~64 Words data)]:
Flash address register: FARH=xxh, FARL=xxh
Write the following data to register:
FD0L=xxh, FD0H=xxh
NO
Write next data
Write Buffer
Finish?
YES
FWT=1
NO
FWT=0 ?
YES
Write Finish ?
NO
Write next Page
YES
Clear CFWEN bit
END
Write Flash Program Procedure
Rev. 1.40
45
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
Read Flash
ROM
FMOD �~0=011
FRDEN=1
flash add�ess �egiste�:
FARH=xxh� FARL=xxh
FRD=1
NO
FRD=0 ?
YE�
Read value:
FD0L=xxh� FD0H=xxh
NO
Read Finish ?
YE�
FRDEN=0
Clea� CFWEN �it
END
Read Flash Program Procedure
Rev. 1.40
46
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
In Circuit Programming – ICP
The provision of Flash type Program Memory provides the user with a means of convenient and
easy upgrades and modifications to their programs on the same device.
As an additional convenience, Holtek has provided a means of programming the microcontroller incircuit using a 4-pin interface. This provides manufacturers with the possibility of manufacturing
their circuit boards complete with a programmed or un-programmed microcontroller, and then
programming or upgrading the program at a later stage. This enables product manufacturers to easily
keep their manufactured products supplied with the latest program releases without removal and reinsertion of the device.
Holtek Writer Pins
MCU Programming Pins
ICPDA
UDN
Programming Serial Data
Pin Description
ICPCK
RES
Programming Clock
VDD
VDD/HVDD
VSS
VSS
Power Supply
Ground
The Program Memory can be programmed serially in-circuit using this 4-wire interface. Data
is downloaded and uploaded serially on a single pin with an additional line for the clock. Two
additional lines are required for the power supply and one line for the reset. The technical details
regarding the in-circuit programming of the devices are beyond the scope of this document and will
be supplied in supplementary literature.
During the programming process, taking control of the UDN and RES pins for data and clock
programming purposes. The user must there take care to ensure that no other outputs are connected
to these two pins.

   
Note: * may be resistor or capacitor. The resistance of * must be greater than 300W or the
capacitance of * must be less than 1nF.
Rev. 1.40
47
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
On-Chip Debug Support – OCDS
There is an EV chip named HT66VB540/HT66VB542/HT66VB550/HT66VB560 which is used
to emulate the HT66FB540/HT66FB542/HT66FB550/HT66FB560 device. The HT66VB540/
HT66VB542/HT66VB550/HT66VB560 device also provides the "On-Chip Debug" function to debug
the HT66FB540/HT66FB542/HT66FB550/HT66FB560 device during development process. The
two devices, HT66FB540/HT66FB542/HT66FB550/HT66FB560 and HT66VB540/HT66VB542/
HT66VB550/HT66VB560, are almost functional compatible except the "On-Chip Debug" function.
Users can use the HT66VB540/HT66VB542/HT66VB550/HT66VB560 device to emulate the
HT66FB540/HT66FB542/HT66FB550/HT66FB560 device behaviors by connecting the OCDSDA
and OCDSCK pins to the Holtek HT-IDE development tools. The OCDSDA pin is the OCDS Data/
Address input/output pin while the OCDSCK pin is the OCDS clock input pin. When users use the
HT66VB540/HT66VB542/HT66VB550/HT66VB560 EV chip for debugging, the corresponding pin
functions shared with the OCDSDA and OCDSCK pins in the HT66FB540/HT66FB542/HT66FB550/
HT66FB560 device will have no effect in the HT66VB540/HT66VB542/HT66VB550/HT66VB560
EV chip. For more detailed OCDS information, refer to the corresponding document named "Holtek
e-Link for 8-bit MCU OCDS User’s Guide".
Holtek e-Link Pins
Rev. 1.40
EV Chip Pins
Pin Description
OCDSDA
OCDSDA
On-Chip Debug Support Data/Address input/output
OCDSCK
OCDSCK
On-Chip Debug Support Clock input
VDD
VDD/HVDD
GND
VSS
Power Supply
Ground
48
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
RAM Data Memory
The Data Memory is a volatile area of 8-bit wide RAM internal memory and is the location where
temporary information is stored.
Structure
Divided into two sections, the first of these is an area of RAM, known as the Special Function Data
Memory. Here are located registers which are necessary for correct operation of the devices. Many
of these registers can be read from and written to directly under program control, however, some
remain protected from user manipulation.
Device
Capacity
Banks
HT66FB540
512×8
0: 80H~FFH
1: 80H~FFH
2: 80H~FFH
3: 80H~FFH
HT66FB542
256×8
0: 80H~FFH
1: 80H~FFH
768×8
0: 80H~FFH
1: 80H~FFH
2: 80H~FFH
3: 80H~FFH
4: 80H~FFH
5: 80H~FFH
1024×8
0: 80H~FFH
1: 80H~FFH
2: 80H~FFH
3: 80H~FFH
4: 80H~FFH
5: 80H~FFH
6: 80H~FFH
7: 80H~FFH
HT66FB550
HT66FB560
The second area of Data Memory is known as the General Purpose Data Memory, which is reserved
for general purpose use. All locations within this area are read and write accessible under program
control.
The overall Data Memory is subdivided into several banks, the structure of which depends upon
these devices chosen. The Special Purpose Data Memory registers are accessible in all banks, with
the exception of the FRCR, FCR, FARH and FDnH registers at address from 40H to 46H, which
are only accessible in Bank 1. Switching between the different Data Memory banks is achieved by
setting the Bank Pointer to the correct value. The start address of the Data Memory for all devices is
the address 00H.
Rev. 1.40
49
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
HT66FB540
00H
01H
0�H
03H
04H
0�H
06H
07H
0�H
09H
0AH
0BH
0CH
Bank 0~3
IAR0
MP0
IAR1
MP1
BP
ACC
PCL
43H
44H
4�H
46H
TBLP
TBLH
47H
4�H
49H
4AH
4BH
4CH
TBHP
�TATU�
�MOD
LVDC
0DH
0EH
INTEG
WDTC
0FH
10H
11H
1�H
TBC
INTC0
13H
14H
1�H
16H
INTC3
MFI0
19H
1AH
1BH
1CH
PAPU
PA
PAC
PADIR
1DH
1EH
1FH
�0H
�1H
��H
PAOI
P�LEW
�3H
�4H
��H
�6H
�7H
��H
PBC
3DH
3EH
3FH
�1H
��H
�3H
�4H
��H
�6H
MFI1
MFI�
PAWU
37H
3�H
39H
3AH
3BH
3CH
4DH
4EH
4FH
�0H
INTC1
INTC�
17H
1�H
�9H
�AH
�BH
�CH
�DH
�EH
�FH
30H
31H
3�H
33H
34H
3�H
36H
Bank 0� �~3
40H
41H
4�H
�7H
��H
�9H
�AH
�BH
�CH
�DH
�EH
�FH
60H
61H
6�H
PXWU
PXPU
PXOI
PB
PD
PDC
PE
PEC
ADRL
ADRH
ADCR0
ADCR1
ACER0
CP0C
CP1C
I�CTOC
�IMC0
�PIAC1
�PIAD
�B�C
FARL
FCR
FARH
FD0L
FD1L
FD0H
FD1H
FD�L
FD�H
FD3L
FD3H
TMPC0
TMPC1
TM0C0
TM0C1
TM0DL
TM0DH
TM0AL
TM0AH
TM0RP
TM1C0
TM1C1
TM1DL
TM1DH
TM1AL
TM1AH
TM�C0
TM�C1
TM�DL
TM�DH
TM�AL
TM�AH
TM3C0
TM3C1
TM3DL
TM3DH
TM3AL
63H
64H
6�H
66H
67H
6�H
69H
6AH
6BH
6CH
6DH
6EH
6FH
70H
71H
7�H
TM3AH
U�B_�TAT
UINT
U�C
73H
74H
7�H
76H
FIFO1
FIFO�
77H
7�H
79H
7AH
7BH
7CH
7DH
7EH
7FH
�IMC1
�IMD
�IMA/�IMC�
�PIAC0
Bank 1
FRCR
U�R
UCC
AWR
�TLI
�TLO
�IE�
MI�C
UFIEN
UFOEN
UFC0
FIFO0
FIFO3
CTRL
LVRC
PAP�0
PAP�1
�Y�C
: Unused� �ead as 00H
HT66FB540 Special Purpose Data Memory
Rev. 1.40
50
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
HT66FB542
00H
01H
0�H
03H
04H
0�H
06H
07H
0�H
09H
0AH
0BH
0CH
0DH
0EH
0FH
10H
11H
1�H
13H
14H
1�H
16H
17H
1�H
19H
1AH
1BH
1CH
1DH
1EH
1FH
�0H
�1H
��H
�3H
�4H
��H
�6H
�7H
��H
�9H
�AH
�BH
�CH
�DH
�EH
�FH
30H
31H
3�H
33H
34H
3�H
36H
37H
3�H
39H
3AH
3BH
3CH
3DH
3EH
3FH
Bank 0~1
IAR0
40H
Bank 0
MP0
IAR1
41H
4�H
MP1
BP
ACC
PCL
TBLP
TBLH
43H
44H
4�H
46H
47H
4�H
FD�L
FD�H
FD3L
FD3H
TMPC0
TMPC1
TBHP
�TATU�
49H
4AH
TM0C0
TM0C1
�MOD
LVDC
4BH
4CH
4DH
4EH
4FH
�0H
INTEG
WDTC
INTC0
INTC1
INTC�
�1H
��H
�3H
�4H
��H
�6H
INTC3
MFI0
MFI1
MFI�
�7H
��H
�9H
�AH
�BH
�CH
�DH
�EH
�FH
60H
61H
6�H
63H
64H
6�H
66H
67H
6�H
69H
6AH
6BH
6CH
6DH
6EH
6FH
70H
71H
7�H
73H
74H
7�H
76H
77H
7�H
79H
7AH
7BH
7CH
7DH
7EH
7FH
PAWU
PAPU
PA
PAC
PADIR
PAOI
P�LEW
PXWU
PXPU
PXOI
PB
PBC
PD
PDC
PE
PEC
ADRL
ADRH
ADCR0
ADCR1
ACER0
CP0C
I�CTOC
�IMC0
�IMC1
�IMD
�IMA/�IMC�
�PIAC0
�PIAC1
�PIAD
�B�C
Bank 1
FRCR
FARL
FCR
FARH
FD0L
FD1L
FD0H
FD1H
TM0DL
TM0DH
TM0AL
TM0AH
TM0RP
TM1C0
TM1C1
TM1DL
TM1DH
TM1AL
TM1AH
TM�C0
TM�C1
TM�DL
TM�DH
TM�AL
TM�AH
TM3C0
TM3C1
TM3DL
TM3DH
TM3AL
TM3AH
U�B_�TAT
UINT
U�C
U�R
UCC
AWR
�TLI
�TLO
�IE�
MI�C
UFIEN
UFOEN
UFC0
FIFO0
FIFO1
FIFO�
FIFO3
CTRL
LVRC
PAP�0
PAP�1
�Y�C
: Unused� �ead as 00H
HT66FB542 Special Purpose Data Memory
Rev. 1.40
51
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
HT66FB550
00H
01H
0�H
03H
04H
0�H
06H
07H
0�H
09H
0AH
0BH
0CH
Bank 0~�
IAR0
MP0
IAR1
MP1
BP
ACC
PCL
TBLP
TBLH
TBHP
�TATU�
�MOD
LVDC
0DH
0EH
0FH
10H
11H
1�H
INTEG
WDTC
13H
14H
1�H
16H
17H
1�H
19H
1AH
1BH
1CH
1DH
1EH
INTC3
MFI0
TBC
INTC0
INTC1
INTC�
PAPU
PA
PAC
PADIR
PAOI
P�LEW
PXWU
PXPU
�3H
�4H
��H
�6H
�7H
��H
�9H
�AH
�BH
�CH
�DH
�EH
�FH
30H
PBC
PC
PCC
PD
37H
3�H
39H
3AH
PXOI
PB
PDC
PE
PEC
ADRL
ADRH
ADCR0
ADCR1
ACER0
ACER1
CP0C
CP1C
I�CTOC
�IMC0
3DH
3EH
�IMC1
�IMD
�IMA/�IMC�
�PIAC0
�PIAC1
�PIAD
3FH
�B�C
3BH
3CH
FARL
FCR
FARH
FD0L
FD1L
FD0H
FD1H
FD�L
FD�H
FD3L
FD3H
TMPC0
TMPC1
4FH
�0H
�1H
��H
TM0AH
TM0RP
�7H
��H
�9H
�AH
�BH
�CH
�DH
�EH
�FH
60H
61H
6�H
63H
64H
6�H
66H
67H
6�H
69H
6AH
6BH
6CH
6DH
6EH
6FH
70H
71H
7�H
73H
74H
7�H
76H
77H
7�H
79H
7AH
PAWU
Bank 1
FRCR
4�H
46H
47H
4�H
49H
4AH
4BH
4CH
4DH
4EH
�3H
�4H
��H
�6H
MFI1
MFI�
1FH
�0H
�1H
��H
31H
3�H
33H
34H
3�H
36H
Bank 0� �~�
40H
41H
4�H
43H
44H
7BH
7CH
7DH
7EH
7FH
TM0C0
TM0C1
TM0DL
TM0DH
TM0AL
TM1C0
TM1C1
TM1DL
TM1DH
TM1AL
TM1AH
TM�C0
TM�C1
TM�DL
TM�DH
TM�AL
TM�AH
TM3C0
TM3C1
TM3DL
TM3DH
TM3AL
TM3AH
U�B_�TAT
UINT
U�C
U�R
UCC
AWR
�TLI
�TLO
�IE�
MI�C
UFIEN
UFOEN
UFC0
UFC1
FIFO0
FIFO1
FIFO�
FIFO3
FIFO4
FIFO�
CTRL
LVRC
PAP�0
PAP�1
�Y�C
: Unused� �ead as 00H
HT66FB550 Special Purpose Data Memory
Rev. 1.40
52
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
HT66FB560
00H
01H
0�H
03H
04H
0�H
06H
07H
0�H
09H
0AH
0BH
0CH
0DH
0EH
0FH
10H
11H
1�H
13H
14H
1�H
16H
17H
1�H
19H
1AH
1BH
1CH
1DH
1EH
Bank 0~7
IAR0
MP0
IAR1
TBLP
TBLH
TBHP
�TATU�
�MOD
LVDC
INTEG
WDTC
TBC
INTC0
INTC1
INTC�
INTC3
MFI0
MFI1
MFI�
PAPU
PA
PAC
PADIR
PAOI
P�LEW
�3H
�4H
��H
�6H
�7H
��H
PBC
PC
PCC
PD
�9H
�AH
�BH
�CH
�DH
�EH
�FH
30H
31H
3�H
33H
34H
PEC
PF
3FH
�7H
��H
�9H
�AH
�BH
�CH
�DH
�EH
PAWU
PXWU
PXPU
37H
3�H
39H
3AH
3BH
3CH
3DH
3EH
41H
4�H
43H
44H
4�H
46H
47H
4�H
49H
4AH
4BH
4CH
4DH
4EH
4FH
�0H
�1H
��H
�3H
�4H
��H
�6H
MP1
BP
ACC
PCL
1FH
�0H
�1H
��H
3�H
36H
Bank 0� �~7
40H
�FH
60H
61H
6�H
63H
64H
6�H
66H
67H
6�H
PXOI
PB
PDC
PE
69H
6AH
6BH
6CH
6DH
6EH
6FH
70H
71H
7�H
73H
74H
7�H
76H
77H
7�H
79H
7AH
PFC
PFPU
PFWU
ADRL
ADRH
ADCR0
ADCR1
ACER0
ACER1
CP0C
CP1C
I�CTOC
�IMC0
�IMC1
�IMD
�IMA/�IMC�
�PIAC0
�PIAC1
�PIAD
�B�C
Bank 1
FRCR
FARL
FCR
FARH
FD0L
FD1L
FD0H
FD1H
FD�L
FD�H
FD3L
FD3H
TMPC0
TMPC1
TM0C0
TM0C1
TM0DL
TM0DH
TM0AL
TM0AH
TM0RP
TM1C0
TM1C1
TM1DL
TM1DH
TM1AL
TM1AH
TM�C0
TM�C1
TM�DL
TM�DH
TM�AL
TM�AH
TM3C0
TM3C1
TM3DL
TM3DH
TM3AL
TM3AH
U�B_�TAT
UINT
U�C
U�R
UCC
AWR
�TLI
�TLO
�IE�
MI�C
UFIEN
UFOEN
UFC0
UFC1
FIFO0
FIFO1
FIFO�
FIFO3
FIFO4
FIFO�
FIFO6
FIFO7
CTRL
7BH
7CH
LVRC
7DH
7EH
7FH
PAP�0
PAP�1
�Y�C
: Unused� �ead as 00H
HT66FB560 Special Purpose Data Memory
Rev. 1.40
53
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
Special Function Register Description
Most of the Special Function Register details will be described in the relevant functional section;
however several registers require a separate description in this section.
Indirect Addressing Registers – IAR0, IAR1
The Indirect Addressing Registers, IAR0 and IAR1, although having their locations in normal RAM
register space, do not actually physically exist as normal registers. The method of indirect addressing
for RAM data manipulation uses these Indirect Addressing Registers and Memory Pointers, in
contrast to direct memory addressing, where the actual memory address is specified. Actions on the
IAR0 and IAR1 registers will result in no actual read or write operation to these registers but rather
to the memory location specified by their corresponding Memory Pointers, MP0 or MP1. Acting as a
pair, IAR0 and MP0 can together access data from Bank 0 while the IAR1 and MP1 register pair can
access data from any bank. As the Indirect Addressing Registers are not physically implemented,
reading the Indirect Addressing Registers indirectly will return a result of "00H" and writing to the
registers indirectly will result in no operation.
Memory Pointers – MP0, MP1
Two Memory Pointers, known as MP0 and MP1 are provided. These Memory Pointers are
physically implemented in the Data Memory and can be manipulated in the same way as normal
registers providing a convenient way with which to address and track data. When any operation to
the relevant Indirect Addressing Registers is carried out, the actual address that the microcontroller
is directed to, is the address specified by the related Memory Pointer. MP0, together with Indirect
Addressing Register, IAR0, are used to access data from Bank 0, while MP1 and IAR1 are used to
access data from all banks according to BP register. Direct Addressing can only be used with Bank 0,
all other Banks must be addressed indirectly using MP1 and IAR1.
The following example shows how to clear a section of four Data Memory locations already defined
as locations adres1 to adres4.
Indirect Addressing Program Example
data .section data
adres1 db ?
adres2 db ?
adres3 db ?
adres4 db ?
block db ?
code .section at 0 code
org00h
start:
mov a,04h;
mov block,a
mov a,offset adres1 ;
mov mp0,a ;
loop:
clr IAR0 ;
inc mp0;
sdz block ;
jmp loop
continue:
setup size of block
Accumulator loaded with first RAM address
setup memory pointer with first RAM address
clear the data at address defined by MP0
increment memory pointer
check if last memory location has been cleared
The important point to note here is that in the example shown above, no reference is made to specific
RAM addresses.
Rev. 1.40
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HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
Bank Pointer – BP
Depending upon which devices are used, the Program and Data Memory are divided into several
banks. Selecting the required Program and Data Memory area is achieved using the Bank Pointer.
Bit 5 of the Bank Pointer is used to select Program Memory Bank 0 or 1, while bits 0~2 are used to
select Data Memory Bank 0~7.
The Data Memory is initialised to Bank 0 after a reset, except for a WDT time-out reset in the Power
Down Mode, in which case, the Data Memory bank remains unaffected. It should be noted that the
Special Function Data Memory is not affected by the bank selection, which means that the Special
Function Registers can be accessed from within any bank. Directly addressing the Data Memory
will always result in Bank 0 being accessed irrespective of the value of the Bank Pointer. Accessing
data from banks other than Bank 0 must be implemented using Indirect addressing.
As both the Program Memory and Data Memory share the same Bank Pointer Register, care must be
taken during programming.
Bit
Device
HT66FB540
7
6
5
4
3
2
1
0
—
—
—
—
—
—
DMBP1
DMBP0
HT66FB542
—
—
—
—
—
—
—
DMBP0
HT66FB550
—
—
—
—
—
DMBP2
DMBP1
DMBP0
HT66FB560
—
—
PMBP0
—
—
DMBP2
DMBP1
DMBP0
BP Registers List
BP Register
• HT66FB540
Bit
7
6
5
4
3
2
1
0
Name
—
—
—
—
—
—
DMBP1
DMBP0
R/W
—
—
—
—
—
—
R/W
R/W
POR
—
—
—
—
—
—
0
0
Bit 7~2
Unimplemented, read as "0"
Bit 1~0DMBP1, DMBP0: Select Data Memory Banks
00: Bank 0
01: Bank 1
10: Bank 2
11: Bank 3
• HT66FB542
Bit
7
6
5
4
3
2
1
0
Name
—
—
—
—
—
—
—
DMBP0
R/W
—
—
—
—
—
—
—
R/W
POR
—
—
—
—
—
—
—
0
Bit 7~1
Unimplemented, read as "0"
Bit 0DMBP0: Select Data Memory Banks
0: Bank 0
1: Bank 1
Rev. 1.40
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HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
• HT66FB550
Bit
7
6
5
4
3
2
1
0
Name
—
—
—
—
—
DMBP2
DMBP1
DMBP0
R/W
—
—
—
—
—
R/W
R/W
R/W
POR
—
—
—
—
—
0
0
0
Bit 7~3
Unimplemented, read as "0"
Bit 1~0DMBP2, DMBP1, DMBP0: Select Data Memory Banks
000: Bank 0
001: Bank 1
010: Bank 2
011: Bank 3
100: Bank 4
101: Bank 5
110~111: Undefined
• HT66FB560
Bit
7
6
5
4
3
2
1
0
Name
—
—
PMBP0
—
—
DMBP2
DMBP1
DMBP0
R/W
—
—
R/W
—
—
R/W
R/W
R/W
POR
—
—
0
—
—
0
0
0
Bit 7~6
Unimplemented, read as "0"
Bit 5PMBP0: Select Program Memory Banks
0: Bank 0, Program Memory Address is from 0000H~1FFFH
1: Bank 1, Program Memory Address is from 2000H~3FFFH
Bit 4~3
Unimplemented, read as "0"
Bit 2~0DMBP2~DMBP0: Select Data Memory Banks
000: Bank 0
001: Bank 1
010: Bank 2
011: Bank 3
100: Bank 4
101: Bank 5
110: Bank 6
111: Bank 7
Accumulator – ACC
The Accumulator is central to the operation of any microcontroller and is closely related with
operations carried out by the ALU. The Accumulator is the place where all intermediate results
from the ALU are stored. Without the Accumulator it would be necessary to write the result of
each calculation or logical operation such as addition, subtraction, shift, etc., to the Data Memory
resulting in higher programming and timing overheads. Data transfer operations usually involve
the temporary storage function of the Accumulator; for example, when transferring data between
one user defined register and another, it is necessary to do this by passing the data through the
Accumulator as no direct transfer between two registers is permitted.
Rev. 1.40
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HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
Program Counter Low Register – PCL
To provide additional program control functions, the low byte of the Program Counter is made
accessible to programmers by locating it within the Special Purpose area of the Data Memory. By
manipulating this register, direct jumps to other program locations are easily implemented. Loading
a value directly into this PCL register will cause a jump to the specified Program Memory location,
however, as the register is only 8-bit wide, only jumps within the current Program Memory page are
permitted. When such operations are used, note that a dummy cycle will be inserted.
Look-up Table Registers – TBLP, TBHP, TBLH
These three special function registers are used to control operation of the look-up table which is
stored in the Program Memory. TBLP and TBHP are the table pointers and indicate the location
where the table data is located. Their value must be setup before any table read commands are
executed. Their value can be changed, for example using the "INC" or "DEC" instructions, allowing
for easy table data pointing and reading. TBLH is the location where the high order byte of the table
data is stored after a table read data instruction has been executed. Note that the lower order table
data byte is transferred to a user defined location.
Status Register – STATUS
This 8-bit register contains the zero flag (Z), carry flag (C), auxiliary carry flag (AC), overflow flag
(OV), power down flag (PDF), and watchdog time-out flag (TO). These arithmetic/logical operation
and system management flags are used to record the status and operation of the microcontroller.
With the exception of the TO and PDF flags, bits in the status register can be altered by instructions
like most other registers. Any data written into the status register will not change the TO or PDF flag.
In addition, operations related to the status register may give different results due to the different
instruction operations. The TO flag can be affected only by a system power-up, a WDT time-out or
by executing the "CLR WDT" or "HALT" instruction. The PDF flag is affected only by executing
the "HALT" or "CLR WDT" instruction or during a system power-up.
The Z, OV, AC and C flags generally reflect the status of the latest operations.
• C is set if an operation results in a carry during an addition operation or if a borrow does not take
place during a subtraction operation; otherwise C is cleared. C is also affected by a rotate through
carry instruction.
• AC is set if an operation results in a carry out of the low nibbles in addition, or no borrow from
the high nibble into the low nibble in subtraction; otherwise AC is cleared.
• Z is set if the result of an arithmetic or logical operation is zero; otherwise Z is cleared.
• OV is set if an operation results in a carry into the highest-order bit but not a carry out of the
highest-order bit, or vice versa; otherwise OV is cleared.
• PDF is cleared by a system power-up or executing the "CLR WDT" instruction. PDF is set by
executing the "HALT" instruction.
• TO is cleared by a system power-up or executing the "CLR WDT" or "HALT" instruction. TO is
set by a WDT time-out.
In addition, on entering an interrupt sequence or executing a subroutine call, the status register will
not be pushed onto the stack automatically. If the contents of the status registers are important and if
the subroutine can corrupt the status register, precautions must be taken to correctly save it.
Rev. 1.40
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September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
STATUS Register
Bit
7
6
5
4
3
2
1
0
Name
—
—
TO
PDF
OV
Z
AC
C
R/W
—
—
R
R
R/W
R/W
R/W
R/W
POR
—
—
0
0
x
x
x
x
" x" unknown
Bit 7, 6
Unimplemented, read as "0"
Bit 5TO: Watchdog Time-Out flag
0: After power up or executing the "CLR WDT" or "HALT" instruction
1: A watchdog time-out occurred.
Bit 4PDF: Power down flag
0: After power up or executing the "CLR WDT" instruction
1: By executing the "HALT" instruction
Bit 3OV: Overflow flag
0: No overflow
1: An operation results in a carry into the highest-order bit but not a carry out of the
highest-order bit or vice versa.
Bit 2Z: Zero flag
0: The result of an arithmetic or logical operation is not zero
1: The result of an arithmetic or logical operation is zero
Bit 1AC: Auxiliary flag
0: No auxiliary carry
1: An operation results in a carry out of the low nibbles in addition, or no borrow
from the high nibble into the low nibble in subtraction
Bit 0C: Carry flag
0: No carry-out
1: An operation results in a carry during an addition operation or if a borrow does
not take place during a subtraction operation
C is also affected by a rotate through carry instruction.
Rev. 1.40
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September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
Oscillators
Various oscillator options offer the user a wide range of functions according to their various
application requirements. The flexible features of the oscillator functions ensure that the best
optimisation can be achieved in terms of speed and power saving. Oscillator selections and operation
are selected through a combination of configuration options and registers.
Oscillator Overview
In addition to being the source of the main system clock the oscillators also provide clock sources
for the Watchdog Timer and Time Base Interrupts. External oscillators requiring some external
components as well as fully integrated internal oscillators, requiring no external components,
are provided to form a wide range of both fast and slow system oscillators. All oscillator
options are selected through the configuration options. The higher frequency oscillators provide
higher performance but carry with it the disadvantage of higher power requirements, while the
opposite is of course true for the lower frequency oscillators. With the capability of dynamically
switching between fast and slow system clock, these devices have the flexibility to optimize the
performance/power ratio, a feature especially important in power sensitive portable applications.
Note that the LXT oscillator and Time Base are not contained in the HT66FB542 device. All of the
mentioned functions related to the LXT oscillator and Time Base in this chapter are not available in
the HT66FB542 device.
Type
Name
Frequency
External Crystal
HXT
6MHz or 12MHz
Internal High Speed RC
HIRC
12MHz
External Low Speed Crystal
LXT
32.768kHz
Internal Low Speed RC
LIRC
32kHz
Pins
OSC1/OSC2
—
XT1/XT2
—
Oscillator Types
Note: For USB applications, HXT must be connected a 6MHz or 12MHz crystal.
System Clock Configurations
There are several oscillator sources, two high speed oscillators and two low speed oscillators. The
high speed system clocks are sourced from the external crystal/ceramic oscillator, the PLL frequency
generator and the internal 12MHz RC oscillator. The two low speed oscillators are the internal
32kHz RC oscillator and the external 32.768kHz crystal oscillator. Note that the LXT oscillator is
not contained in the HT66FB542 device. Selecting whether the low or high speed oscillator is used
as the system oscillator is implemented using the HLCLK bit and CKS2~CKS0 bits in the SMOD
register and as the system clock can be dynamically selected. The actual source clock used for each
of the high speed and low speed oscillators is chosen via configuration options. The frequency of the
slow speed or high speed system clock is also determined using the HLCLK bit and CKS2~CKS0
bits in the SMOD register. Note that two oscillator selections must be made namely one high speed
and one low speed system oscillators. It is not possible to choose a no-oscillator selection for either
the high or low speed oscillator. In addition, the internal PLL frequency generator, whose clock
source is supplied by an external crystal oscillator, can be enabled by a software control bit to
generate various frequencies for the USB interface and system clock.
Rev. 1.40
59
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
U�BCKEN �it
4�MHz
Config.O�tion
�elects
6 o� 1�MHz HXT
HXT
To U�B
Ci�cuits
HO�C
16MHz
HO�C
÷�
6MHz
1�MHz
PLL
HIRC
�Y�CLK
Bit
�Y�CLK
�it
fH/�
fH/4
fH/�
fH/16
fH/3�
PLL �it
HO�C
PLL �it
P�escale�
PLL clock
6MHz
High ��eed
Oscillato� Configu�ation
O�tion
fH
F�Y�16MHz
�it
U�BCKEN
�it
fH/64
fH
fL
LIRC
f�Y�
Low ��eed
Oscillato�
HCLK�
CK��~CK�0 �its
fL
Fast Wake-u� f�o�
�LEEP o� IDLE Mode
Cont�ol (fo� HXT only)
System Clock Configurations – HT66FB542
U�BCKEN �it
4�MHz
Config.O�tion
�elects
6 o� 1�MHz HXT
HXT
To U�B
Ci�cuits
HO�C
16MHz
HO�C
÷�
6MHz
PLL
HIRC
1�MHz
�Y�CLK
Bit
PLL �it
HO�C
PLL �it
P�escale�
PLL clock
6MHz
High ��eed
Oscillato� Configu�ation
O�tion
fH
�Y�CLK
�it
F�Y�16MHz
�it
U�BCKEN
�it
LIRC
fH/�
fH/4
fH/�
fH/16
fH/3�
fH/64
fH
fL
f�Y�
LXT
Low ��eed
Oscillato� Configu�ation
O�tion
HCLK�
CK��~CK�0 �its
fL
Fast Wake-u� f�o�
�LEEP o� IDLE Mode
Cont�ol (fo� HXT only)
System Clock Configurations – HT66FB540/HT66FB550/HT66FB560
External Crystal Oscillator – HXT
The External Crystal/Ceramic System Oscillator is one of the high frequency oscillators. For most
crystal oscillator configurations, the simple connection of a crystal across OSC1 and OSC2 will
create the necessary phase shift and feedback for oscillation, without requiring external capacitors.
However, for some crystal types and frequencies, to ensure oscillation, it may be necessary to add
two small value capacitors, C1 and C2. Using a ceramic resonator will usually require two small
value capacitors, C1 and C2, to be connected as shown for oscillation to occur. The values of C1
and C2 should be selected in consultation with the crystal or resonator manufacturer's specification.
For USB applications, the HXT pins must be connected to a 6MHz or 12MHz crystal if the HXT
oscillator is selected to be used.
For oscillator stability and to minimise the effects of noise and crosstalk, it is important to ensure
that the crystal and any associated resistors and capacitors along with interconnecting lines are all
located as close to the MCU as possible.
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     Crystal Oscillator – HXT
Crystal Oscillator C1 and C2 Values
Crystal Frequency
C1
C2
16MHz
0pF
0pF
12MHz
0pF
0pF
8MHz
0pF
0pF
6MHz
0pF
0pF
4MHz
0pF
0pF
1MHz
100pF
100pF
Note: 1. C1 and C2 values are for guidance only.
Crystal Recommended Capacitor Values
Note: For USB applications, HXT must be connected a 6MHz or 12MHz crystal.
Internal PLL Frequency Generator
The internal PLL frequency generator is used to generate the frequency for the USB interface and
the system clock. This PLL generator can be enabled or disabled by the PLL control bit in the USC
register. After a power on reset, the PLL control bit will be set to "0" to turn on the PLL generator.
The PLL generator will provide the fixed 48MHz frequency for the USB operating frequency
and another frequency for the system clock source which can be 6MHz, 12MHz or 16MHz. The
selection of this system frequency is implemented using the SYSCLK, Fsys16MHZ and USBCKEN bits in the UCC register. In addition, the system clock can be selected as the HXT via these control
bits. The CLK_ADJ bit is used to adjust the PLL clock automatically.
SYSC Register
Bit
7
6
5
4
3
2
1
0
Name
CLK_ADJ
USBdis
RUBUS
—
—
HFV
—
—
R/W
R/W
R/W
R/W
—
—
R/W
—
—
POR
0
0
0
—
—
0
—
—
Bit 7CLK_ADJ: PLL Clock Automatic Adjustment function
0: Disable
1: Enable
Note that if the user selects the HIRC as the system clock, the CLK_ADJ bit must be
set to "1" to adjust the PLL frequency automatically.
Bit 6USBdis: USB SIE control bit
USB related control bit, described elsewhere
Bit 5RUBUS: UBUS pin pull low resistor
USB related control bit, described elsewhere
Bit 4~3 Rev. 1.40
unimplemented, read as "0"
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Bit 2 HFV: Non-USB mode high frequency voltage control
0: For USB mode - bit must be cleared to zero.
1: For non-USB mode - bit must be set high. Ensures that the higher frequency
can work at lower voltages.
A higher frequency is >8MHz and is used for the system clock fH.
Bit 1~0 unimplemented, read as "0"
UCC Register
Bit
7
Name
Rctrl
6
5
4
R/W
R/W
R/W
R/W
R/W
POR
0
0
0
x
3
2
1
0
—
EPS1
EPS0
R/W
—
R/W
R/W
0
—
x
x
SYSCLK Fsys16MHz SUSP2 USBCKEN
"x": unknown
Bit 7Rctrl: 7.5kΩ resistor between UDP and UBUS control bit
USB related control bit, described elsewhere
Bit 6SYSCLK: System clock frequency select bit
0: 12MHz
1: 6MHz
Note: If a 6MHz crystal or resonator is used for the MCU, this bit should be set to "1".
If a 12MHz crystal or resonator is used, then this bit should be set to "0".
If the 12MHz HIRC is selected, then this bit must be set to "0".
Bit 5Fsys16MHZ: PLL 16MHz output control bit
0: HXT
1: PLL 16MHz
Bit 4SUSP2: Reduce power consumption in suspend mode control bit
USB related control bit, described elsewhere
Bit 3USBCKEN: USB clock control bit
0: Disable
1: Enable
Bit 2
Unimplemented, read as "0"
Bit 1~0EPS1, EPS0: Accessing endpoint FIFO selection
USB related control bit, described elsewhere
USC Register
Bit
7
6
5
Name
URD
SELPS2
PLL
4
R/W
R/W
R/W
R/W
R/W
POR
1
0
0
0
3
2
1
0
URST
RMWK
SUSP
R
R/W
R/W
R
x
x
x
x
SELUSB RESUME
"x": unknown
Bit 7URD: USB reset signal control function definition
USB related control bit, described elsewhere
Bit 6SELPS2: the chip works under PS2 mode indicator bit
USB related control bit, described elsewhere
Bit 5PLL: PLL control bit
0: Turn-on PLL
1: Turn-off PLL
Bit 4SELUSB: the chip works under USB mode indicator bit
USB related control bit, described elsewhere
Bit 3RESUME: USB resume indication bit
USB related control bit, described elsewhere
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Bit 2URST: USB reset indication bit
USB related control bit, described elsewhere
Bit 1RMWK: USB remote wake-up command
USB related control bit, described elsewhere
Bit 0SUSP: USB suspend indication
USB related control bit, described elsewhere
The following table illustrates the PLL output frequency selected by the related control bits.
High frequency system clock fH selection table:
PLL
USBCKEN
Fsys16MHz
0
0
0
HOSC (HXT or HIRC)
fH
0
0
1
fPLL – 16MHz
0
1
0
fPLL – 6MHz or 12 MHz, depending on the "SYSCLK" bit
in the UCC register selection
0
1
1
fPLL – 16MHz
1
x
x
HOSC (HXT or HIRC)
x: stand for "don’t care"
Internal RC Oscillator – HIRC
The internal RC oscillator is a fully integrated system oscillator requiring no external components.
The internal RC oscillator has a fixed frequency of 12MHz. Device trimming during the
manufacturing process and the inclusion of internal frequency compensation circuits are used to
ensure that the influence of the power supply voltage, temperature and process variations on the
oscillation frequency are minimised. As a result, at a power supply of either 3.3V or 5V and at a
temperature of 25˚C degrees, the fixed oscillation frequency of 12MHz will have a tolerance within
3% (Non-USB mode). Note that if this internal system clock option is selected, as it requires no
external pins for its operation, I/O pins PD0 and PD1 are free for use as normal I/O pins. The HIRC
has its own power supply pin, HVDD. The HVDD pin must be connected to VDD and an 0.1mF
capacitor to ground.
External 32.768kHz Crystal Oscillator – LXT
The External 32.768kHz Crystal System Oscillator is one of the low frequency oscillator choices,
which is selected via configuration option. Note that the LXT oscillator is not contained in
the HT66FB542 device. This clock source has a fixed frequency of 32.768kHz and requires
a 32.768kHz crystal to be connected between pins XT1 and XT2. The external resistor and
capacitor components connected to the 32.768kHz crystal are necessary to provide oscillation. For
applications where precise frequencies are essential, these components may be required to provide
frequency compensation due to different crystal manufacturing tolerances. During power-up there is
a time delay associated with the LXT oscillator waiting for it to start-up.
When the microcontroller enters the SLEEP or IDLE Mode, the system clock is switched off to stop
microcontroller activity and to conserve power. However, in many microcontroller applications it
may be necessary to keep the internal timers operational even when the microcontroller is in the
SLEEP or IDLE Mode. To do this, another clock, independent of the system clock, must be provided.
However, for some crystals, to ensure oscillation and accurate frequency generation, it is necessary
to add two small value external capacitors, C1 and C2. The exact values of C1 and C2 should be
selected in consultation with the crystal or resonator manufacturer’s specification. The external
parallel feedback resistor, Rp, is required.
Some configuration options determine if the XT1/XT2 pins are used for the LXT oscillator or as I/O
pins.
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• If the LXT oscillator is not used for any clock source, the XT1/XT2 pins can be used as normal
I/O pins.
• If the LXT oscillator is used for any clock source, the 32.768kHz crystal should be connected to
the XT1/XT2 pins.
For oscillator stability and to minimise the effects of noise and crosstalk, it is important to ensure
thatthe crystal and any associated resistors andcapacitors along with interconnectinglines are all
located as close to the MCUas possible.
‚   
­ €
  ‚  External LXT Oscillator
LXT Oscillator C1 and C2 Values
Crystal Frequency
C1
C2
32.768kHz
10pF
10pF
Note: 1. C1 and C2 values are for guidance only.
2. RP=5M~10M is recommended.
32.768kHz Crystal Recommended Capacitor Values
LXT Oscillator Low Power Function
The LXT oscillator can function in one of two modes, the Quick Start Mode and the Low Power
Mode. The mode selection is executed using the LXTLP bit in the TBC register.
LXTLP Bit
LXT Mode
0
Quick Start
1
Low-power
After power on the LXTLP bit will be automatically cleared to zero ensuring that the LXT oscillator
is in the Quick Start operating mode. In the Quick Start Mode the LXT oscillator will power up
and stabilise quickly. However, after the LXT oscillator has fully powered up it can be placed
into the Low-power mode by setting the LXTLP bit high. The oscillator will continue to run but
with reduced current consumption, as the higher current consumption is only required during the
LXT oscillator start-up. In power sensitive applications, such as battery applications, where power
consumption must be kept to a minimum, it is therefore recommended that the application program
sets the LXTLP bit high about 2 seconds after power-on.
It should be noted that, no matter what condition the LXTLP bit is set to, the LXT oscillator will
always function normally, the only difference is that it will take more time to start up if in the
Low-power mode.
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Internal 32kHz Oscillator – LIRC
The Internal 32kHz System Oscillator is one of the low frequency oscillator choices, which is
selected via configuration option. It is a fully integrated RC oscillator with a typical frequency of
32kHz at 5V, requiring no external components for its implementation. Device trimming during
the manufacturing process and the inclusion of internal frequency compensation circuits are used
to ensure that the influence of the power supply voltage, temperature and process variations on the
oscillation frequency are minimised. As a result, at a power supply of 5V and at a temperature of
25˚C degrees, the fixed oscillation frequency of 32kHz will have a tolerance within 10%.
Supplementary Internal Clocks
The low speed oscillators, in addition to providing a system clock source are also used to provide
a clock source to two other devices functions. These are the Watchdog Timer and the Time Base
Interrupts.
Operating Modes and System Clocks
Present day applications require that their microcontrollers have high performance but often still
demand that they consume as little power as possible, conflicting requirements that are especially
true in battery powered portable applications. The fast clocks required for high performance will
by their nature increase current consumption and of course vice versa, lower speed clocks reduce
current consumption. As Holtek has provided these devices with both high and low speed clock
sources and the means to switch between them dynamically, the user can optimise the operation of
their microcontroller to achieve the best performance/power ratio.
System Clocks
The devices have many different clock sources for both the CPU and peripheral function operation.
By providing the user with a wide range of clock options using configuration options and register
programming, a clock system can be configured to obtain maximum application performance.
The main system clock, can come from either a high frequency, fH, or low frequency, fL, source,
and is selected using the HLCLK bit and CKS2~CKS0 bits in the SMOD register. The high speed
system clock can be sourced from either a HXT, PLL frequency generator or HIRC oscillator,
selected via a configuration option together with the PLL, USBCKEN and Fsys16MHZ control bits.
The low speed system clock source can be sourced from internal clock fL. If fL is selected then it
can be sourced by either the LXT or LIRC oscillators, selected via a configuration option. The other
choice, which is a divided version of the high speed system oscillator has a range of fH/2~fH/64.
There are two additional internal clocks for the peripheral circuits, the substitute clock, fSUB, and
the Time Base clock, fTBC. Each of these internal clocks is sourced by either the LXT or LIRC
oscillators, selected via configuration options. The fSUB clock is used to provide a substitute clock for
the microcontroller just after a wake-up has occurred to enable faster wake-up times.
Note that the LXT oscillator and Time Base are not contained in the HT66FB542 device. All of the
mentioned functions related to the LXT oscillator and Time Base in this chapter are not available in
the HT66FB542 device.
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A/D Flash USB 8-Bit MCU with SPI
U�BCKEN �it
4�MHz
Config.O�tion
�elects
6 o� 1�MHz HXT
HXT
To U�B
Ci�cuits
HO�C
16MHz
HO�C
÷�
6MHz
1�MHz
PLL
HIRC
�Y�CLK
Bit
�Y�CLK
�it
fH/�
fH/4
fH/�
fH/16
fH/3�
PLL �it
HO�C
PLL �it
P�escale�
PLL clock
6MHz
High ��eed
Oscillato� Configu�ation
O�tion
fH
F�Y�16MHz
�it
U�BCKEN
�it
fH/64
fH
fL
LIRC
f�Y�
Low ��eed
Oscillato�
HCLK�
CK��~CK�0 �its
fL
f�UB
Fast Wake-u� f�o�
�LEEP o� IDLE Mode
Cont�ol (fo� HXT only)
WDT
Device Clock Configurations – HT66FB542
U�BCKEN �it
4�MHz
Config.O�tion
�elects
6 o� 1�MHz HXT
HXT
To U�B
Ci�cuits
HO�C
16MHz
HO�C
÷�
6MHz
PLL
HIRC
1�MHz
�Y�CLK
Bit
�Y�CLK
�it
fH/�
fH/4
fH/�
fH/16
fH/3�
PLL �it
HO�C
PLL �it
P�escale�
PLL clock
6MHz
High ��eed
Oscillato� Configu�ation
O�tion
fH
F�Y�16MHz
�it
U�BCKEN
�it
fH/64
fH
fL
LIRC
f�Y�
LXT
Low ��eed
Oscillato� Configu�ation
O�tion
HCLK�
CK��~CK�0 �its
fL
f�UB
fTBC
f�Y�/4
Fast Wake-u� f�o�
�LEEP o� IDLE Mode
Cont�ol (fo� HXT only)
WDT
fTB
P�escale�
Ti�e
Bases
TBCK TB1[1:0] TB0[�:0]
Device Clock Configurations – HT66FB540/HT66FB550/HT66FB560
Note: When the system clock source fSYS is switched to fL from fH, the high speed oscillation will
stop to conserve the power. Thus there is no fH~fH/64 for peripheral circuit to use.
The fSUB clock is used as one of the clock sources for the Watchdog timer. For the HT66FB540/
HT66FB550/HT66FB560, the fTBC clock is used as a source for the Time Base interrupt functions
and for the TMs. While for the HT66FB542, the fL clock is used as a source for the Time Base
interrupt functions and for the TMs.
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A/D Flash USB 8-Bit MCU with SPI
System Operation Modes
There are six different modes of operation for the microcontroller, each one with its own
special characteristics and which can be chosen according to the specific performance and
power requirements of the application. There are two modes allowing normal operation of the
microcontroller, the NORMAL Mode and SLOW Mode. The remaining four modes, the SLEEP0,
SLEEP1, IDLE0 and IDLE1 Mode are used when the microcontroller CPU is switched off to
conserve power.
Operation Mode
Description
CPU
fSYS
fSUB
fTBC
NORMAL Mode
On
fH~fH/64
On
On
SLOW Mode
On
fL
On
On
IDLE0 Mode
Off
Off
On
On
IDLE1 Mode
Off
On
On
On
SLEEP0 Mode
Off
Off
Off
Off
SLEEP1 Mode
Off
Off
On
Off
Note: The fTBC clock is not available in the HT66FB542 device.
NORMAL Mode
As the name suggests this is one of the main operating modes where the microcontroller has all of
its functions operational and where the system clock is provided by one of the high speed oscillators.
This mode operates allowing the microcontroller to operate normally with a clock source will come
from one of the high speed oscillators, either the PLL frequency generator, HXT or HIRC oscillators.
The high speed oscillator will however first be divided by a ratio ranging from 1 to 64, the actual ratio
being selected by the CKS2~CKS0 and HLCLK bits in the SMOD register. Although a high speed
oscillator is used, running the microcontroller at a divided clock ratio reduces the operating current.
SLOW Mode
This is also a mode where the microcontroller operates normally although now with a slower speed
clock source. The clock source used will be from one of the low speed oscillators, either the LXT
or the LIRC. Running the microcontroller in this mode allows it to run with much lower operating
currents. In the SLOW Mode, the fH is off.
SLEEP0 Mode
The SLEEP0 Mode is entered when an HALT instruction is executed and when the IDLEN bit in
the SMOD register is low. In the SLEEP0 mode the CPU will be stopped, and the fSUB clock will be
stopped too, and the Watchdog Timer function is disabled. In this mode, the LVDEN is must set to
"0". If the LVDEN is set to "1", it won’t enter the SLEEP0 Mode.
SLEEP1 Mode
The SLEEP1 Mode is entered when an HALT instruction is executed and when the IDLEN bit in the
SMOD register is low. In the SLEEP1 mode the CPU will be stopped. However, the fSUB clock will
continue to operate if the LVDEN is "1" or the Watchdog Timer function is enabled.
IDLE0 Mode
The IDLE0 Mode is entered when a HALT instruction is executed and when the IDLEN bit in the
SMOD register is high and the FSYSON bit in the CTRL register is low. In the IDLE0 Mode the
system oscillator will be inhibited from driving the CPU but some peripheral functions will remain
operational such as the Watchdog Timer, TMs and SIM. In the IDLE0 Mode, the system oscillator
will be stopped. In the IDLE0 Mode the Watchdog Timer clock, fSUB, will be on.
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A/D Flash USB 8-Bit MCU with SPI
IDLE1 Mode
The IDLE1 Mode is entered when an HALT instruction is executed and when the IDLEN bit in the
SMOD register is high and the FSYSON bit in the CTRL register is high. In the IDLE1 Mode the
system oscillator will be inhibited from driving the CPU but may continue to provide a clock source
to keep some peripheral functions operational such as the Watchdog Timer, TMs and SIM. In the
IDLE1 Mode, the system oscillator will continue to run, and this system oscillator may be high speed
or low speed system oscillator. In the IDLE1 Mode the Watchdog Timer clock, fSUB, will be on.
Control Register
A single register, SMOD, is used for overall control of the internal clocks within these devices.
SMOD Register
Bit
7
6
5
4
3
2
1
0
Name
CKS2
CKS1
CKS0
FSTEN
LTO
HTO
IDLEN
HLCLK
R/W
R/W
R/W
R/W
R/W
R
R
R/W
R/W
POR
0
0
0
0
0
0
1
1
Bit 7~5CKS2~CKS0: The system clock selection when HLCLK is "0"
000: fL (fLXT or fLIRC)
001: fL (fLXT or fLIRC)
010: fH/64
011: fH/32
100: fH/16
101: fH/8
110: fH/4
111: fH/2
These three bits are used to select which clock is used as the system clock source. In
addition to the system clock source, which can be either the LXT or LIRC, a divided
version of the high speed system oscillator can also be chosen as the system clock
source. Note that the fLXT clock is not available in the HT66FB542 device.
Bit 4FSTEN: Fast Wake-up Control (only for HXT)
0: Disable
1: Enable
This is the Fast Wake-up Control bit which determines if the fSUB clock source is
initially used after these devices wakes up. When the bit is high, the fSUB clock source
can be used as a temporary system clock to provide a faster wake up time as the fSUB
clock is available.
Bit 3LTO: Low speed system oscillator ready flag
0: Not ready
1: Ready
This is the low speed system oscillator ready flag which indicates when the low speed
system oscillator is stable after power on reset or a wake-up has occurred. The flag
will be low when in the SLEEP0 Mode but after a wake-up has occurred, the flag will
change to a high level after 1024 clock cycles if the LXT oscillator is used and 1~2
clock cycles if the LIRC oscillator is used.
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Bit 2HTO: High speed system oscillator ready flag
0: Not ready
1: Ready
This is the high speed system oscillator ready flag which indicates when the high
speed system oscillator is stable. This flag is cleared to "0" by hardware when these
devices are powered on and then changes to a high level after the high speed system
oscillator is stable. Therefore this flag will always be read as "1" by the application
program after devices power-on. The flag will be low when in the SLEEP or IDLE0
Mode but after a wake-up has occurred, the flag will change to a high level after 1024
clock cycles if the HXT oscillator is used and after 1024 clock cycles if the HIRC
oscillator is used.
Bit 1IDLEN: IDLE Mode control
0: Disable
1: Enable
This is the IDLE Mode Control bit and determines what happens when the HALT
instruction is executed. If this bit is high, when a HALT instruction is executed these
devices will enter the IDLE Mode. In the IDLE1 Mode the CPU will stop running
but the system clock will continue to keep the peripheral functions operational, if
FSYSON bit is high. If FSYSON bit is low, the CPU and the system clock will all
stop in IDLE0 mode. If the bit is low these devices will enter the SLEEP Mode when a
HALT instruction is executed.
Bit 0HLCLK: System clock selection
0: fH/2~fH/64 or fL
1: fH
This bit is used to select if the fH clock or the fH/2~fH/64 or fL clock is used as the
system clock. When the bit is high the f H clock will be selected and if low the
fH/2~fH/64 or fL clock will be selected. When system clock switches from the fH clock
to the fL clock and the fH clock will be automatically switched off to conserve power.
CTRL Register
Bit
7
6
5
4
3
2
1
0
Name
FSYSON
—
—
—
—
R/W
R/W
—
—
—
—
LVRF
LRF
WRF
R/W
R/W
POR
0
—
—
—
—
R/W
x
0
0
"x": unknown
Bit 7FSYSON: fSYS Control in IDLE Mode
0: Disable
1: Enable
Bit 6~3
Unimplemented, read as "0"
Bit 2LVRF: LVR function reset flag
Described elsewhere.
Bit 1LRF: LVR Control register software reset flag
Described elsewhere.
Bit 0WRF: WDT Control register software reset flag
Described elsewhere.
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Fast Wake-up
To minimise power consumption these devices can enter the SLEEP or IDLE0 Mode, where the
system clock source to these devices will be stopped. However when these devices are woken
up again, it can take a considerable time for the original system oscillator to restart, stabilise and
allow normal operation to resume. To ensure the device is up and running as fast as possible a Fast
Wake-up function is provided, which allows fSUB, namely either the LXT or LIRC oscillator, to act
as a temporary clock to first drive the system until the original system oscillator has stabilised. As
the clock source for the Fast Wake-up function is fSUB, the Fast Wake-up function is only available in
the SLEEP1 and IDLE0 modes. When these devices are woken up from the SLEEP0 mode, the Fast
Wake-up function has no effect because the fSUB clock is stopped. The Fast Wake-up enable/disable
function is controlled using the FSTEN bit in the SMOD register.
If the HXT oscillator is selected as the NORMAL Mode system clock, and if the Fast Wake-up
function is enabled, then it will take one to two tSUB clock cycles of the LIRC or LXT oscillator for
the system to wake-up. The system will then initially run under the fSUB clock source until 1024
HXT clock cycles have elapsed, at which point the HTO flag will switch high and the system will
switch over to operating from the HXT oscillator.
If the HIRC oscillator or LIRC oscillator is used as the system oscillator then it will take 1024 clock
cycles of the HIRC or 1~2 cycles of the LIRC to wake up the system from the SLEEP or IDLE0
Mode. The Fast Wake-up bit, FSTEN will have no effect in these cases.
System FSTEN
Oscillator
Bit
Wake-up Time
(SLEEP0 Mode)
Wake-up Time
(SLEEP1 Mode)
Wake-up Time
(IDLE0 Mode)
Wake-up Time
(IDLE1 Mode)
1024 HXT cycles
1024 HXT cycles
1
1024 HXT cycles
1~2 fSUB cycles (System runs with fSUB first
for 1024 HXT cycles and then switches
1~2 HXT cycles
over to run with the HXT clock)
HIRC
X
1024 HIRC cycles
1024 HIRC cycles
1~2 HIRC cycles
LIRC
X
1~2 LIRC cycles
1~2 LIRC cycles
1~2 LIRC cycles
LXT
X
1024 LXT cycles
1024 LXT cycles
1~2 LXT cycles
0
HXT
1~2 HXT cycles
Wake-Up Times
Note that if the Watchdog Timer is disabled, which means that the LXT and LIRC are all both off,
then there will be no Fast Wake-up function available when these devices wake-up from the SLEEP0
Mode. Also note that the LXT oscillator is not contained in the HT66FB542 device.
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Operating Mode Switching and Wake-up
These devices can switch between operating modes dynamically allowing the user to select the best
performance/power ratio for the present task in hand. In this way microcontroller operations that
do not require high performance can be executed using slower clocks thus requiring less operating
current and prolonging battery life in portable applications.
In simple terms, Mode Switching between the NORMAL Mode and SLOW Mode is executed
using the HLCLK bit and CKS2~CKS0 bits in the SMOD register while Mode Switching from the
NORMAL/SLOW Modes to the SLEEP/IDLE Modes is executed via the HALT instruction. When
a HALT instruction is executed, whether these devices enter the IDLE Mode or the SLEEP Mode
is determined by the condition of the IDLEN bit in the SMOD register and FSYSON in the CTRL
register.
When the HLCLK bit switches to a low level, which implies that clock source is switched from the
high speed clock source, fH, to the clock source, fH/2~fH/64 or fL. If the clock is from the fL, the high
speed clock source will stop running to conserve power. When this happens it must be noted that the
fH/16 and fH/64 internal clock sources will also stop running, which may affect the operation of other
internal functions such as the TMs and the SIM. The accompanying flowchart shows what happens
when these devices move between the various operating modes.
­ €    
­ €    Note: The fTBC clock is not available in the HT66FB542 device.
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NORMAL Mode to SLOW Mode Switching
When running in the NORMAL Mode, which uses the high speed system oscillator, and therefore
consumes more power, the system clock can switch to run in the SLOW Mode by set the HLCLK bit
to "0" and set the CKS2~CKS0 bits to "000" or "001" in the SMOD register. This will then use the
low speed system oscillator which will consume less power. Users may decide to do this for certain
operations which do not require high performance and can subsequently reduce power consumption.
The SLOW Mode is sourced from the LXT or the LIRC oscillators and therefore requires these
oscillators to be stable before full mode switching occurs. This is monitored using the LTO bit in the
SMOD register.
  
     ­          ­   € ‚      ­   € ‚      ­   Rev. 1.40
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SLOW Mode to NORMAL Mode Switching
In SLOW Mode the system uses either the LXT or LIRC low speed system oscillator. To switch
back to the NORMAL Mode, where the high speed system oscillator is used, the HLCLK bit should
be set to "1" or HLCLK bit is "0", but CKS2~CKS0 is set to "010", "011", "100", "101", "110" or
"111". As a certain amount of time will be required for the high frequency clock to stabilise, the
status of the HTO bit is checked. The amount of time required for high speed system oscillator
stabilization depends upon which high speed system oscillator type is used.
  
   ­   ­       ­   ­  €‚ ƒ    ­   ­  €‚ ƒ    ­   ­  Entering the SLEEP0 Mode
There is only one way for these devices to enter the SLEEP0 Mode and that is to execute the
"HALT" instruction in the application program with the IDLEN bit in SMOD register equal to "0"
and the WDT and LVD both off. When this instruction is executed under the conditions described
above, the following will occur:
• The system clock, WDT clock and Time Base clock will be stopped and the application program
will stop at the "HALT" instruction.
• The Data Memory contents and registers will maintain their present condition.
• The WDT will be cleared and stopped.
• The I/O ports will maintain their present conditions.
• In the status register, the Power Down flag, PDF, will be set and the Watchdog time-out flag, TO,
will be cleared.
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Entering the SLEEP1 Mode
There is only one way for these devices to enter the SLEEP1 Mode and that is to execute the
"HALT" instruction in the application program with the IDLEN bit in SMOD register equal to "0"
and the WDT or LVD on. When this instruction is executed under the conditions described above,
the following will occur:
• The system clock and Time Base clock will be stopped and the application program will stop at
the "HALT" instruction, but the WDT or LVD will remain with the clock source coming from the
fSUB clock.
• The Data Memory contents and registers will maintain their present condition.
• The WDT will be cleared and resume counting if the WDT is enabled.
• The I/O ports will maintain their present conditions.
• In the status register, the Power Down flag, PDF, will be set and the Watchdog time-out flag, TO,
will be cleared.
Entering the IDLE0 Mode
There is only one way for these devices to enter the IDLE0 Mode and that is to execute the "HALT"
instruction in the application program with the IDLEN bit in SMOD register equal to "1" and the
FSYSON bit in CTRL register equal to "0". When this instruction is executed under the conditions
described above, the following will occur:
• The system clock will be stopped and the application program will stop at the "HALT"
instruction, but the Time Base clock and fSUB clock will be on.
• The Data Memory contents and registers will maintain their present condition.
• The WDT will be cleared and resume counting if the WDT is enabled.
• The I/O ports will maintain their present conditions.
• In the status register, the Power Down flag, PDF, will be set and the Watchdog time-out flag, TO,
will be cleared.
Entering the IDLE1 Mode
There is only one way for these devices to enter the IDLE1 Mode and that is to execute the "HALT"
instruction in the application program with the IDLEN bit in SMOD register equal to "1" and the
FSYSON bit in CTRL register equal to "1". When this instruction is executed under the conditions
described above, the following will occur:
• The system clock and Time Base clock and fSUB clock will be on and the application program will
stop at the "HALT" instruction.
• The Data Memory contents and registers will maintain their present condition.
• The WDT will be cleared and resume counting if the WDT is enabled.
• The I/O ports will maintain their present conditions.
• In the status register, the Power Down flag, PDF, will be set and the Watchdog time-out flag, TO,
will be cleared.
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Standby Current Considerations
As the main reason for entering the SLEEP or IDLE Mode is to keep the current consumption of
these devices to as low a value as possible, perhaps only in the order of several micro-amps except
in the IDLE1 Mode, there are other considerations which must also be taken into account by the
circuit designer if the power consumption is to be minimised. Special attention must be made to
the I/O pins on these devices. All high-impedance input pins must be connected to either a fixed
high or low level as any floating input pins could create internal oscillations and result in increased
current consumption. This also applies to devices which have different package types, as there may
be unbonded pins. These must either be setup as outputs or if setup as inputs must have pull-high
resistors connected.
Care must also be taken with the loads, which are connected to I/O pins, which are setup as outputs.
These should be placed in a condition in which minimum current is drawn or connected only to
external circuits that do not draw current, such as other CMOS inputs. Also note that additional
standby current will also be required if the configuration options have enabled the LXT or LIRC
oscillator.
In the IDLE1 Mode the system oscillator is on, if the system oscillator is from the high speed
system oscillator, the additional standby current will also be perhaps in the order of several hundred
micro-amps.
Wake-up
After the system enters the SLEEP or IDLE Mode, it can be woken up from one of various sources
listed as follows:
• An external or USB reset
• An external rising or falling edge on I/O Port
• A system interrupt
• A WDT overflow
If the system is woken up by an external or USB reset, these devices will experience a full system
reset, however, if these devices are woken up by a WDT overflow, a Watchdog Timer reset will be
initiated. Although both of these wake-up methods will initiate a reset operation, the actual source
of the wake-up can be determined by examining the TO and PDF flags. The PDF flag is cleared by a
system power-up or executing the clear Watchdog Timer instructions and is set when executing the
"HALT" instruction. The TO flag is set if a WDT time-out occurs, and causes a wake-up that only
resets the Program Counter and Stack Pointer, the other flags remain in their original status.
Each pin on I/O Port can be setup using the PAWU, PXWU or PFWU register to permit a negative
transition on the pin to wake-up the system. When a pin wake-up occurs, the program will resume
execution at the instruction following the "HALT" instruction. If the system is woken up by an
interrupt, then two possible situations may occur. The first is where the related interrupt is disabled
or the interrupt is enabled but the stack is full, in which case the program will resume execution
at the instruction following the "HALT" instruction. In this situation, the interrupt which woke-up
these devices will not be immediately serviced, but will rather be serviced later when the related
interrupt is finally enabled or when a stack level becomes free. The other situation is where the
related interrupt is enabled and the stack is not full, in which case the regular interrupt response
takes place. If an interrupt request flag is set high before entering the SLEEP or IDLE Mode, the
wake-up function of the related interrupt will be disabled.
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Programming Considerations
The HXT and LXT oscillators both use the same SST counter. For example, if the system is woken
up from the SLEEP0 Mode and both the HXT and LXT oscillators need to start-up from an off state.
The LXT oscillator uses the SST counter after HXT oscillator has finished its SST period.
• If these devices are woken up from the SLEEP0 Mode to the NORMAL Mode, the high speed
system oscillator needs an SST period. These devices will execute first instruction after HTO
is "1". At this time, the LXT oscillator may not be stability if fSUB is from LXT oscillator. The
same situation occurs in the power-on state. The LXT oscillator is not ready yet when the first
instruction is executed.
• If these devices are woken up from the SLEEP1 Mode to NORMAL Mode, and the system clock
source is from HXT oscillator and FSTEN is "1", the system clock can be switched to the LXT or
LIRC oscillator after wake up.
• There are peripheral functions, such as WDT, TMs and SIM, for which the fSYS is used. If the
system clock source is switched from fH to fL, the clock source to the peripheral functions
mentioned above will change accordingly.
• The on/off condition of fSUB depends upon whether the WDT is enabled or disabled as the WDT
clock source is selected from fSUB.
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Watchdog Timer
The Watchdog Timer is provided to prevent program malfunctions or sequences from jumping to
unknown locations, due to certain uncontrollable external events such as electrical noise.
Watchdog Timer Clock Source
The Watchdog Timer clock source is provided by the internal clock, fSUB, which can be sourced from
either the LXT or LIRC oscillators, chosen via a configuration option. Note that the LXT oscillator
is not contained in the HT66FB542 device. The Watchdog Timer source clock is then subdivided by
a ratio of 28 to 218 to give longer timeouts, the actual value being chosen using the WS2~WS0 bits
in the WDTC register. The LIRC internal oscillator has an approximate period of 32kHz at a supply
voltage of 5V.
However, it should be noted that this specified internal clock period can vary with VDD, temperature
and process variations. The WDT function is allowed to enable or disable by setting the WDTC
register data.
Watchdog Timer Control Register
A single register, WDTC, controls the required timeout period as well as the enable/disable
operation. The WRF software reset flag will be indicated in the CTRL register.
WDTC Register
Bit
7
6
5
4
3
2
1
0
Name
WE4
WE3
WE2
WE1
WE0
WS2
WS1
WS0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
1
0
1
0
0
1
1
Bit 7~3WE4~WE0: WDT function software control
10101: WDT Disabled
01010: WDT Enabled
Other values: Reset MCU
When these bits are changed to any other values due to environmental noise the
microcontroller will be reset; this reset operation will be activated after 2~3 LIRC
clock cycles and the WRF bit in the CTRL register will be set to 1 to indicate the reset
source.
Bit 2~0
Rev. 1.40
WS2, WS1, WS0: WDT time-out period selection
000: 28/fSUB
001: 210/fSUB
010: 212/fSUB
011: 214/fSUB
100: 215/fSUB
101: 216/fSUB
110: 217/fSUB
111: 218/fSUB
These three bits determine the division ratio of the Watchdog Timer source clock,
which in turn determines the timeout period.
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CTRL Register
Bit
7
6
5
4
3
2
Name
FSYSON
—
—
R/W
R/W
—
—
POR
0
—
—
—
1
0
—
—
—
—
LVRF
LRF
WRF
R/W
R/W
—
R/W
x
0
0
Bit 7FSYSON: fSYS Control in IDLE Mode
Described elsewhere.
Bit 6~3
Unimplemented, read as "0"
Bit 2LVRF: LVR function reset flag
Described elsewhere.
Bit 1LRF: LVR Control register software reset flag
Described elsewhere.
Bit 0WRF: WDT Control register software reset flag
0: Not occurred
1: Occurred
This bit is set to 1 by the WDT Control register software reset and cleared by the
application program. Note that this bit can only be cleared to 0 by the application
program.
Watchdog Timer Operation
The Watchdog Timer operates by providing a device reset when its timer overflows. This means
that in the application program and during normal operation the user has to strategically clear the
Watchdog Timer before it overflows to prevent the Watchdog Timer from executing a reset. This is
done using the clear watchdog instructions. If the program malfunctions for whatever reason, jumps
to an unknown location, or enters an endless loop, these clear instructions will not be executed in
the correct manner, in which case the Watchdog Timer will overflow and reset these devices. With
regard to the Watchdog Timer enable/disable function, there are also five bits, WE4~WE0, in the
WDTC register to offer additional enable/disable and reset control of the Watchdog Timer.
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WDT Enable/Disabled using the WDT Control Register
The WDT is enabled/disabled using the WDT control register, the WE4~WE0 values can determine
which mode the WDT operates in. The WDT will be disabled when the WE4~WE0 bits are set to a
value of 10101B. The WDT function will be enabled if the WE4~WE0 bit value is equal to 01010B.
If the WE4~WE0 bits are set to any other values other than 01010B and 10101B, it will reset these
devices after 2~3 LIRC clock cycles. After power on these bits will have the value of 01010B.
WDT
WE4~WE0 Bits
WDT Function
10101B
Disable
Controlled by WDT Control Register
01010B
Enable
Any other value
Reset MCU
Watchdog Timer Enable/Disable Control
Under normal program operation, a Watchdog Timer time-out will initialise a device reset and set
the status bit TO. However, if the system is in the SLEEP or IDLE Mode, when a Watchdog Timer
time-out occurs, the TO bit in the status register will be set and only the Program Counter and Stack
Pointer will be reset. Four methods can be adopted to clear the Watchdog Timer contents. The first
is a WDT reset, which means a value other than 01010B or 10101B is written into the WE4~WE0
bit locations, the second is to use the Watchdog Timer software clear instructions, the third is via
a HALT instruction and the fourth is an external hardware reset, which means a low level on the
external RES pin. There is only one method of using software instruction to clear the Watchdog
Timer and that is to use the single "CLR WDT" instruction to clear the WDT.
The maximum time out period is when the 218 division ratio is selected. As an example, with a
32kHz LIRC oscillator as its source clock, this will give a maximum watchdog period of around 8
seconds for the 218 division ratio, and a minimum timeout of 7.8ms for the 28 division ration.
WDTC Registe�
WE4~WE0 �its
Reset MCU
“CLR WDT” Inst�uction
CLR
“HALT” Inst�uction
RE� �in �eset
f�UB
�-stage Divide�
f�UB/��
W��~W�0
WDT P�escale�
WDT Ti�e-out
(��/f�UB ~ �1�/f�UB)
�-to-1 MUX
Watchdog Timer
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Reset and Initialisation
A reset function is a fundamental part of any microcontroller ensuring that these devices can be set
to some predetermined condition irrespective of outside parameters. A hardware reset will of course
be automatically implemented after these devices are powered-on, however there are a number of
other hardware and software reset sources that can be implemented dynamically when these devices
are running.
Reset Overview
The most important reset condition is after power is first applied to the microcontroller. In this case,
internal circuitry will ensure that the microcontroller, after a short delay, will be in a well defined
state and ready to execute the first program instruction. After this power-on reset, certain important
internal registers will be set to defined states before the program instructions commence execution.
One of these registers is the Program Counter, which will be reset to zero forcing the microcontroller
to begin program execution from the lowest Program Memory address.
These devices provide several reset sources to generate the internal reset signal, providing extended
MCU protection. The different types of resets are listed in the accompanying table.
Abbreviation
Indication Bit
Register
Notes
Power-On Reset
Reset Name
POR
—
—
Auto generated at power on
Reset Pin
RES
—
—
Hardware Reset
Low Voltage Reset
LVR
LVRF
CTRL
Low VDD voltage
Watchdog Reset
WDT
TO
STATUS
WDTC Register Setting
Software Reset
—
—
WRF
CTRL
Write to WDTC register
LVRC Register Setting
Software Reset
—
LRF
CTRL
Write to LVRC register
Reset Source Summary
In addition to the power-on reset, situations may arise where it is necessary to forcefully apply a
reset condition when the microcontroller is running. One example of this is where after power has
been applied and the microcontroller is already running, the RES line is forcefully pulled low. In
such a case, known as a normal operation reset, some of the registers remain unchanged allowing
the microcontroller to proceed with normal operation after the reset line is allowed to return high.
Another type of reset is when the Watchdog Timer overflows and resets the microcontroller. All
types of reset operations result in different register conditions being setup. Another reset exists in
the form of a Low Voltage Reset, LVR, where a full reset, similar to the RES reset is implemented in
situations where the power supply voltage falls below a certain threshold.
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Reset Functions
There are several ways in which a microcontroller reset can occur, through events occurring both
internally and externally:
Power-on Reset
The most fundamental and unavoidable reset is the one that occurs after power is first applied to
the microcontroller. As well as ensuring that the Program Memory begins execution from the first
memory address, a power-on reset also ensures that certain other registers are preset to known
conditions. All the I/O port and port control registers will power up in a high condition ensuring
that all pins will be first set to inputs.
Power-on Reset Timing Chart
Note: tRSTD is power-on delay, typical time=50ms
RES Pin Reset
Although the microcontroller has an internal RC reset function, if the VDD power supply rise time
is not fast enough or does not stabilise quickly at power-on, the internal reset function may be
incapable of providing proper reset operation. For this reason it is recommended that an external
RC network is connected to the RES pin, whose additional time delay will ensure that the RES pin
remains low for an extended period to allow the power supply to stabilise. During this time delay,
normal operation of the microcontroller will be inhibited. After the RES line reaches a certain
voltage value, the reset delay time tRSTD is invoked to provide an extra delay time after which
the microcontroller will begin normal operation. The abbreviation SST in the figures stands for
System Start-up Timer.
For most applications a resistor connected between VDD and the RES pin and a capacitor
connected between VSS and the RES pin will provide a suitable external reset circuit. Any
wiring connected to the RES pin should be kept as short as possible to minimise any stray noise
interference.
For applications that operate within an environment where more noise is present the Enhanced
Reset Circuit shown is recommended.
Note: * It is recommended that this component is added for added ESD protection.
** It is recommended that this component is added in environments where
power line noise is significant.
Extern RES Circuit
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More information regarding external reset circuits is located in Application Note HA0075E on
the Holtek website.
Pulling the RES Pin low using external hardware will also execute a device reset. In this case, as
in the case of other resets, the Program Counter will reset to zero and program execution initiated
from this point.
RES Reset Timing Chart
Note: tRSTD is power-on delay, typical time=16.7ms
Low Voltage Reset – LVR
The microcontroller contains a low voltage reset circuit in order to monitor the supply voltage of
the devices and provide an MCU reset should the value fall below a certain predefined level.
The LVR function is always enabled with a specific LVR voltage VLVR. If the supply voltage of
the devices drops to within a range of 0.9V~VLVR such as might occur when changing the battery
in battery powered applications, the LVR will automatically reset the devices internally and the
LVRF bit in the CTRL register will also be set to 1. For a valid LVR signal, a low supply voltage,
i.e., a voltage in the range between 0.9V~VLVR must exist for a time greater than that specified
by tLVR in the LVD & LVR characteristics. If the low supply voltage state does not exceed this
value, the LVR will ignore the low supply voltage and will not perform a reset function. The
actual VLVR value can be selected by the LVS bits in the LVRC register. If the LVS7~LVS0 bits
are changed to some different values by environmental noise, the LVR will reset the devices after
2~3 LIRC clock cycles. When this happens, the LRF bit in the CTRL register will be set to 1.
After power on the register will have the value of 01010101B. Note that the LVR function will be
automatically disabled when the devices enters the power down mode.
Low Voltage Reset Timing Chart
Note: tRSTD is power-on delay, typical time=16.7ms
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• LVRC Register
Bit
7
6
5
4
3
2
1
0
Name
LVS7
LVS6
LVS5
LVS4
LVS3
LVS2
LVS1
LVS0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
1
0
1
0
1
0
1
Bit 7~0LVS7~LVS0: LVR Voltage Select control
01010101: 2.1V
00110011: 2.55V
10011001: 3.15V
10101010: 3.8V
Any other value: Generates MCU reset – register is reset to POR value
When an actual low voltage condition occurs, as specified by one of the four defined
LVR voltage values above, an MCU reset will be generated. The reset operation will
be activated after 2~3 LIRC clock cycles. In this situation the register contents will
remain the same after such a reset occurs.
Any register value, other than the four defined LVR values above, will also result in
the generation of an MCU reset. The reset operation will be activated after 2~3 LIRC
clock cycles. However in this situation the register contents will be reset to the POR
value.
• CTRL Register
Bit
7
6
5
4
3
2
1
0
Name
FSYSON
—
—
—
—
R/W
R/W
—
—
—
—
LVRF
LRF
WRF
R/W
R/W
POR
0
—
—
—
—
R/W
x
0
0
Bit 7FSYSON: fSYS Control in IDLE Mode
Describe elsewhere.
Bit 6~3
Unimplemented, read as 0
Bit 2LVRF: LVR function reset flag
0: Not occur
1: Occurred
This bit is set to 1 when a specific Low Voltage Reset situation condition occurs. This
bit can only be cleared to 0 by the application program.
Bit 1LRF: LVR Control register software reset flag
0: Not occur
1: Occurred
This bit is set to 1 if the LVRC register contains any non defined LVR voltage register
values. This in effect acts like a software reset function. This bit can only be cleared to
0 by the application program.
Bit 0WRF: WDT Control register software reset flag
Describe elsewhere.
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Watchdog Time-out Reset during Normal Operation
The Watchdog time-out Reset during normal operation is the same as a hardware RES pin reset
except that the Watchdog time-out flag TO will be set to "1".
WDT Time-out Reset during Normal Operation Timing Chart
Note: tRSTD is power-on delay, typical time=16.7ms
Watchdog Time-out Reset during SLEEP or IDLE Mode
The Watchdog time-out Reset during SLEEP or IDLE Mode is a little different from other kinds
of reset. Most of the conditions remain unchanged except that the Program Counter and the Stack
Pointer will be cleared to "0" and the TO flag will be set to "1". Refer to the A.C. Characteristics
for tSST details.
WDT Time-out Reset during SLEEP or IDLE Timing Chart
Note: The tSST is 15~16 clock cycles if the system clock source is provided by HIRC.
The tSST is 1024 clock for HXT or LXT. The tSST is 1~2 clock for LIRC.
WDTC Register Software Reset
A WDTC software reset will be generated when a value other than "10101" or "01010", exist in the
highest five bits of the WDTC register. The WRF bit in the CTRL register will be set high when this
occurs, thus indicating the generation of a WDTC software reset.
WDTC Register
Rev. 1.40
Bit
7
6
5
4
3
2
1
0
Name
WE4
WE3
WE2
WE1
WE0
WS2
WS1
WS0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
1
0
1
0
0
1
1
Bit 7~3
WE4, WE3, WE2, WE1, WE0: WDT Software Control
10101: WDT Disable
01010: WDT Enable (default)
Other: MCU reset
Bit 2~0
WS2, WS1, WS0 : WDT time-out period selection
Described elsewhere
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Reset Initial Conditions
The different types of reset described affect the reset flags in different ways. These flags, known
as PDF and TO are located in the status register and are controlled by various microcontroller
operations, such as the SLEEP or IDLE Mode function or Watchdog Timer. The reset flags are
shown in the table:
TO
0
u
PDF
0
u
RESET Conditions
Power-on reset
RES, LVR or USB reset during NORMAL or SLOW Mode operation
1
u
WDT time-out reset during NORMAL or SLOW Mode operation
1
1
WDT time-out reset during IDLE or SLEEP Mode operation
"u" stands for unchanged
The following table indicates the way in which the various components of the microcontroller are
affected after a power-on reset occurs.
Item
Condition After RESET
Program Counter
Reset to zero
Interrupts
All interrupts will be disabled
WDT
Clear after reset, WDT begins counting
Timer Modules
Timer Modules will be turned off
Input/Output Ports
I/O ports will be setup as inputs, and AN0~ANn is as A/D input pin.
Stack Pointer
Stack Pointer will point to the top of the stack
The different kinds of resets all affect the internal registers of the microcontroller in different ways.
To ensure reliable continuation of normal program execution after a reset occurs, it is important to
know what condition the microcontroller is in after a particular reset occurs. The following table
describes how each type of reset affects each of the microcontroller internal registers. Note that
where more than one package type exists the table will reflect the situation for the larger package
type.
Rev. 1.40
85
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
The HT66FB540 register states are summarized below:
Register
WDT Time-out/
RES Reset/
Reset
WDTC Software LVRC Software RES Reset
(Power On) Reset (Normal Reset (Normal
(HALT)
Operation)
Operation)
WDT
Time-out
(HALT)*
USB-reset USB-reset
(Normal)
(HALT)
MP0
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
xxxx xxxx
xxxx xxxx
MP1
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
xxxx xxxx
xxxx xxxx
ACC
xxxx xxxx
uuuu uuuu
uuuu uuuu
uuuu uuuu
uuuu uuuu uuuu uuuu uuuu uuuu
PCL
0000 0000
0000 0000
0000 0000
0000 0000
0000 0000 0000 0000 0000 0000
TBLP
xxxx xxxx
uuuu uuuu
uuuu uuuu
uuuu uuuu
uuuu uuuu uuuu uuuu uuuu uuuu
TBLH
xxxx xxxx
uuuu uuuu
uuuu uuuu
uuuu uuuu
uuuu uuuu uuuu uuuu uuuu uuuu
TBHP
---- xxxx
---- uuuu
---- uuuu
---- uuuu
---- uuuu
---- uuuu
---- uuuu
STATUS
--00 xxxx
--1u uuuu
--uu uuuu
--01 uuuu
--11 uuuu
--uu uuuu
--uu uuuu
BP
SMOD
---- --00
---- --00
---- --00
---- --00
---- --uu
---- --00
---- --00
0000 0011
0000 0011
0000 0011
0000 0011
uuuu uuuu
0000 0011
0000 0011
INTEG
---- 0000
---- 0000
---- 0000
---- 0000
---- uuuu
---- 0000
---- 0000
LVDC
--00 -000
--00 -000
--00 -000
--00 -000
--uu -uuu
--00 -000
--00 -000
-000 0000
-000 0000
INTC0
-000 0000
-000 0000
-000 0000
-000 0000
-uuu uuuu
INTC1
0000 0000
0000 0000
0000 0000
0000 0000
uuuu uuuu 0000 0000 0000 0000
uuuu uuuu 0000 0000 0000 0000
INTC2
0000 0000
0000 0000
0000 0000
0000 0000
INTC3
-000 -000
-000 -000
-000 -000
-000 -000
-uuu -uuu
MFI0
0000 0000
0000 0000
0000 0000
0000 0000
uuuu uuuu 0000 0000 0000 0000
MFI1
0000 0000
0000 0000
0000 0000
0000 0000
uuuu uuuu 0000 0000 0000 0000
MFI2
-0-0 -0-0
-0-0 -0-0
-0-0 -0-0
-0-0 -0-0
-u-u -u-u
-0-0 -0-0
-0-0 -0-0
PA
1111 1111
1111 1111
1111 1111
1111 1111
uuuu uuuu
1111 1111
1111 1111
-000 -000
-000 -000
PAC
1111 1111
1111 1111
1111 1111
1111 1111
uuuu uuuu
1111 1111
1111 1111
PB
-111 1111
-111 1111
-111 1111
-111 1111
-uuu uuuu
-111 1111
-111 1111
PBC
-111 1111
-111 1111
-111 1111
-111 1111
-uuu uuuu
-111 1111
-111 1111
PD
--11 1111
--11 1111
--11 1111
--11 1111
--uu uuuu
--11 1111
--11 1111
PDC
--11 1111
--11 1111
--11 1111
--11 1111
--uu uuuu
--11 1111
--11 1111
PE
---1 1101
---1 1101
---1 1101
---1 1101
---u uuuu
---1 1101
---1 1101
PEC
---1 1111
---1 1111
---1 1111
---1 1111
---u uuuu
---1 1111
---1 1111
ADRL
(ADRFS=0)
xxxx ----
xxxx ----
xxxx ----
xxxx ----
uuuu ----
xxxx ----
xxxx ----
ADRL
(ADRFS=1)
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
xxxx xxxx
xxxx xxxx
ADRH
(ADRFS=0)
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
xxxx xxxx
xxxx xxxx
ADRH
(ADRFS=1)
---- xxxx
---- xxxx
---- xxxx
---- xxxx
---- uuuu
---- xxxx
---- xxxx
0110 -000
ADCR0
0110 -000
0110 -000
0110 -000
0110 -000
uuuu -uuu
0110 -000
ADCR1
00-0 -000
00-0 -000
00-0 -000
00-0 -000
uu-u -uuu
00-0 -000
00-0 -000
ACER0
1111 1111
1111 1111
1111 1111
1111 1111
uuuu uuuu
1111 1111
1111 1111
WDTC
0101 0011
0101 0011
0101 0011
0101 0011
uuuu uuuu
0101 0011
0101 0011
TBC
0011 0111
0011 0111
0011 0111
0011 0111
uuuu uuuu
0011 0111
0011 0111
---0 ---0
---0 ---0
---0 ---0
---0 ---0
---u ---u
---0 ---0
---0 ---0
FCR
0000 0000
0000 0000
0000 0000
0000 0000
uuuu uuuu 0000 0000 0000 0000
FRCR
FARL
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
xxxx xxxx
FARH
---- xxxx
---- xxxx
---- xxxx
---- xxxx
---- uuuu
---- xxxx
---- xxxx
FD0L
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
xxxx xxxx
xxxx xxxx
FD0H
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
xxxx xxxx
xxxx xxxx
Rev. 1.40
86
xxxx xxxx
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
Register
WDT Time-out/
RES Reset/
Reset
WDTC Software LVRC Software RES Reset
(Power On) Reset (Normal Reset (Normal
(HALT)
Operation)
Operation)
WDT
Time-out
(HALT)*
USB-reset USB-reset
(Normal)
(HALT)
FD1L
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
xxxx xxxx
xxxx xxxx
FD1H
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
xxxx xxxx
xxxx xxxx
FD2L
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
xxxx xxxx
xxxx xxxx
FD2H
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
xxxx xxxx
xxxx xxxx
FD3L
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
FD3H
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
I2CTOC
0000 0000
0000 0000
0000 0000
0000 0000
uuuu uuuu 0000 0000 0000 0000
SIMC0
1110 000-
1110 000-
1110 000-
1110 000-
uuuu uuu-
SIMC1
1000 0001
1000 0001
1000 0001
1000 0001
uuuu uuuu 1000 0001 1000 0001
SIMD
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
SIMA/SIMC2 0000 0000
0000 0000
0000 0000
0000 0000
uuuu uuuu 0000 0000 0000 0000
SPIAC0
111- --0-
111- --0-
111- --0-
111- --0-
SPIAC1
--00 0000
--00 0000
--00 0000
SPIAD
xxxx xxxx
xxxx xxxx
xxxx xxxx
SBSC
0-00 ---0
0-00 ---0
PAWU
0000 0000
0000 0000
1110 000xxxx xxxx
1110 000xxxx xxxx
uuu- --u-
111- --0-
111- --0-
--00 0000
--uu uuuu
--00 0000
--00 0000
xxxx xxxx
uuuu uuuu
xxxx xxxx
xxxx xxxx
0-00 ---0
0-00 ---0
u-uu ---u
0-00 ---0
0-00 ---0
0000 0000
0000 0000
uuuu uuuu 0000 0000 0000 0000
PADIR
0000 0000
0000 0000
0000 0000
0000 0000
uuuu uuuu 0000 0000 0000 0000
PAPU
0000 0000
0000 0000
0000 0000
0000 0000
uuuu uuuu 0000 0000 0000 0000
PXPU
0000 --00
0000 --00
0000 --00
0000 --00
uuuu --uu
PAOI
0000 0000
0000 0000
0000 0000
0000 0000
uuuu uuuu 0000 0000 0000 0000
PSLEW
0000 0000
0000 0000
0000 0000
0000 0000
uuuu uuuu 0000 0000 0000 0000
PXWU
0000 0000
0000 0000
0000 0000
0000 0000
uuuu uuuu 0000 0000 0000 0000
PXOI
0000 --00
0000 --00
0000 --00
0000 --00
uuuu --uu
0000 --00
0000 --00
CP0C
1000 0--1
1000 0--1
1000 0--1
1000 0--1
uuuu u--u
1000 0--1
1000 0--1
CP1C
1000 0--1
1000 0--1
1000 0--1
1000 0--1
uuuu u--u
1000 0--1
1000 0--1
TMPC0
--01 --01
--01 --01
--01 --01
--01 --01
--uu --uu
--01 --01
--01 --01
TMPC1
--0- --0-
--0- --0-
--0- --0-
--0- --0-
--u- --u-
--0- --0-
--0- --0-
uuuu u---
0000 0---
0000 0---
TM0C0
0000 0---
0000 0---
0000 0---
0000 0---
TM0C1
0000 0000
0000 0000
0000 0000
0000 0000
0000 --00
0000 --00
uuuu uuuu 0000 0000 0000 0000
TM0DL
0000 0000
0000 0000
0000 0000
0000 0000
uuuu uuuu 0000 0000 0000 0000
TM0DH
0000 0000
0000 0000
0000 0000
0000 0000
uuuu uuuu 0000 0000 0000 0000
TM0AL
0000 0000
0000 0000
0000 0000
0000 0000
uuuu uuuu 0000 0000 0000 0000
TM0AH
0000 0000
0000 0000
0000 0000
0000 0000
uuuu uuuu 0000 0000 0000 0000
TM0RP
0000 0000
0000 0000
0000 0000
0000 0000
uuuu uuuu 0000 0000 0000 0000
TM1C0
0000 0000
0000 0000
0000 0000
0000 0000
uuuu uuuu 0000 0000 0000 0000
TM1C1
0000 0000
0000 0000
0000 0000
0000 0000
uuuu uuuu 0000 0000 0000 0000
TM1DL
0000 0000
0000 0000
0000 0000
0000 0000
uuuu uuuu 0000 0000 0000 0000
TM1DH
---- --00
---- --00
---- --00
---- --00
TM1AL
0000 0000
0000 0000
0000 0000
0000 0000
---- --uu
---- --00
---- --00
uuuu uuuu 0000 0000 0000 0000
TM1AH
---- --00
---- --00
---- --00
---- --00
TM2C0
0000 0000
0000 0000
0000 0000
0000 0000
uuuu uuuu 0000 0000 0000 0000
TM2C1
0000 0000
0000 0000
0000 0000
0000 0000
uuuu uuuu 0000 0000 0000 0000
TM2DL
0000 0000
0000 0000
0000 0000
0000 0000
uuuu uuuu 0000 0000 0000 0000
TM2DH
---- --00
---- --00
---- --00
---- --00
TM2AL
0000 0000
0000 0000
0000 0000
0000 0000
TM2AH
---- --00
---- --00
---- --00
---- --00
Rev. 1.40
87
---- --uu
---- --uu
---- --00
---- --00
---- --00
---- --00
uuuu uuuu 0000 0000 0000 0000
---- --uu
---- --00
---- --00
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
Register
WDT Time-out/
RES Reset/
Reset
WDTC Software LVRC Software RES Reset
(Power On) Reset (Normal Reset (Normal
(HALT)
Operation)
Operation)
WDT
Time-out
(HALT)*
USB-reset USB-reset
(Normal)
(HALT)
TM3C0
0000 0000
0000 0000
0000 0000
0000 0000
uuuu uuuu 0000 0000 0000 0000
TM3C1
0000 0000
0000 0000
0000 0000
0000 0000
uuuu uuuu 0000 0000 0000 0000
uuuu uuuu 0000 0000 0000 0000
TM3DL
0000 0000
0000 0000
0000 0000
0000 0000
TM3DH
---- --00
---- --00
---- --00
---- --00
TM3AL
0000 0000
0000 0000
0000 0000
0000 0000
TM3AH
USB_STAT
---- --uu
---- --00
---- --00
uuuu uuuu 0000 0000 0000 0000
---- --00
---- --00
---- --00
---- --00
---- --uu
---- --00
---- --00
11xx 000x
uuxx uuux
uuxx uuux
uuxx uuux
uuxx uuux
uuxx uuux
uuxx uuux
---- uuuu
---- uuuu
UINT
---- 0000
---- uuuu
---- uuuu
---- uuuu
---- uuuu
USC
1000 xxxx
uuuu xuux
uuuu xuux
uuuu xuux
uuuu xuux
uuuu 0100 uuuu 0100
USR
---- xxxx
---- uuuu
---- uuuu
---- uuuu
---- uuuu
---- uuuu
---- uuuu
UCC
000x 0-xx
uuuu u-uu
uuuu u-uu
uuuu u-uu
uuuu u-uu
uuu0 u-00
uuu0 u-00
AWR
xxxx xxxx
uuuu uuuu
uuuu uuuu
uuuu uuuu
uuuu uuuu 0000 0000 0000 0000
STLI
---- xxxx
---- uuuu
---- uuuu
---- uuuu
---- uuuu
---- 0000
STLO
---- xxx-
---- uuu-
---- uuu-
---- uuu-
---- uuu-
---- 000-
---- 000-
SIES
xx-x xxxx
uu-x xuuu
uu-x xuuu
uu-x xuuu
uu-x xuuu
00-0 0000
00-0 0000
000- 0000
---- 0000
MISC
xxx- xxxx
xxu- uuxx
xxu- uuxx
xxu- uuxx
xxu- uuxx
000- 0000
UFIEN
---- 0000
---- uuuu
---- uuuu
---- uuuu
---- uuuu
---- uuuu
---- uuuu
FIFO0
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
FIFO1
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
FIFO2
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
FIFO3
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
UFOEN
---- 0000
---- uuuu
---- uuuu
---- uuuu
---- uuuu
---- uuuu
---- uuuu
UFC0
0000 00--
uuuu uu--
uuuu uu--
uuuu uu--
uuuu uu--
uuuu uu--
uuuu uu--
PAPS0
0000 0000
0000 0000
0000 0000
0000 0000
uuuu uuuu 0000 0000 0000 0000
PAPS1
0000 0000
0000 0000
0000 0000
0000 0000
uuuu uuuu 0000 0000 0000 0000
SYSC
000- -0--
000- -0--
000- -0--
000- -0--
uuu- -u--
000- -0--
000- -0--
CTRL
0--- -x00
0--- -x00
0--- -x00
0--- -x00
u--- -xuu
0--- -x00
0--- -x00
LVRC
0101 0101
0101 0101
0101 0101
0101 0101
uuuu uuuu 0101 0101 0101 0101
Note: "*" stands for "warm reset"
"-" not implement
"u" stands for "unchanged"
"x" stands for "unknown"
Rev. 1.40
88
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
The HT66FB542 register states are summarized below:
Register
WDT Time-out/
RES Reset/
Reset
WDTC Software LVRC Software RES Reset
(Power On) Reset (Normal Reset (Normal
(HALT)
Operation)
Operation)
WDT
Time-out
(HALT)*
USB-reset USB-reset
(Normal)
(HALT)
MP0
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
xxxx xxxx
xxxx xxxx
MP1
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
xxxx xxxx
xxxx xxxx
ACC
xxxx xxxx
uuuu uuuu
uuuu uuuu
uuuu uuuu uuuu uuuu uuuu uuuu
uuuu uuuu
PCL
0000 0000
0000 0000
0000 0000
0000 0000 0000 0000 0000 0000
0000 0000
TBLP
xxxx xxxx
uuuu uuuu
uuuu uuuu
uuuu uuuu uuuu uuuu uuuu uuuu
uuuu uuuu
TBLH
xxxx xxxx
uuuu uuuu
uuuu uuuu
uuuu uuuu uuuu uuuu uuuu uuuu
uuuu uuuu
TBHP
---- xxxx
---- uuuu
---- uuuu
---- uuuu
---- uuuu
---- uuuu
---- uuuu
STATUS
--00 xxxx
--1u uuuu
--uu uuuu
--01 uuuu
--11 uuuu
--uu uuuu
--uu uuuu
---- ---0
---- ---0
---- ---0
---- ---0
---- ---u
---- ---0
---- ---0
SMOD
0000 0011
0000 0011
0000 0011
INTEG
---- 0000
---- 0000
---- 0000
BP
0000 0011 uuuu uuuu 0000 0011
---- 0000
---- uuuu
---- 0000
0000 0011
---- 0000
LVDC
--00 -000
--00 -000
--00 -000
--00 -000
--uu -uuu
--00 -000
--00 -000
INTC0
-000 0000
-000 0000
-000 0000
-000 0000
-uuu uuuu
-000 0000
-000 0000
uu-u uu-u
INTC1
00-0 00-0
00-0 00-0
00-0 00-0
00-0 00-0
00-0 00-0
00-0 00-0
INTC2
0000 0000
0000 0000
0000 0000
0000 0000 uuuu uuuu 0000 0000
0000 0000
INTC3
-0-- -0--
-0-- -0--
-0-- -0--
MFI0
0000 0000
0000 0000
0000 0000
0000 0000 uuuu uuuu 0000 0000
-0-- -0--
-u-- -u--
-0-- -0--
0000 0000
-0-- -0--
0000 0000 uuuu uuuu 0000 0000
0000 0000
MFI1
0000 0000
0000 0000
0000 0000
MFI2
-0-0 -0-0
-0-0 -0-0
-0-0 -0-0
-0-0 -0-0
-u-u -u-u
-0-0 -0-0
-0-0 -0-0
PA
1111 1111
1111 1111
1111 1111
1111 1111
uuuu uuuu
1111 1111
1111 1111
PAC
1111 1111
1111 1111
1111 1111
1111 1111
uuuu uuuu
1111 1111
1111 1111
---- 1111
---- 1111
---- 1111
---- 1111
---- uuuu
---- 1111
---- 1111
PB
PBC
---- 1111
---- 1111
---- 1111
---- 1111
---- uuuu
---- 1111
---- 1111
PD
---1 -111
---1 -111
---1 -111
---1 -111
---u -uuu
---1 -111
---1 -111
PDC
---1 -111
---1 -111
---1 -111
---1 -111
---u -uuu
---1 -111
---1 -111
PE
---- --01
---- --01
---- --01
---- --01
---- --uu
---- --01
---- --01
PEC
---- --11
---- --11
---- --11
---- --11
---- --uu
---- --11
---- --11
ADRL
(ADRFS=0)
xxxx ----
xxxx ----
xxxx ----
xxxx ----
uuuu ----
xxxx ----
xxxx ----
ADRL
(ADRFS=1)
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
xxxx xxxx
xxxx xxxx
ADRH
(ADRFS=0)
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
xxxx xxxx
xxxx xxxx
ADRH
(ADRFS=1)
---- xxxx
---- xxxx
---- xxxx
---- xxxx
---- uuuu
---- xxxx
---- xxxx
ADCR0
0110 --00
0110 --00
0110 --00
0110 --00
uuuu --uu
0110 --00
0110 --00
ADCR1
00-0 -000
00-0 -000
00-0 -000
00-0 -000
uu-u -uuu
00-0 -000
00-0 -000
ACER0
---- 1111
---- 1111
---- 1111
---- 1111
---- uuuu
---- 1111
---- 1111
WDTC
0101 0011
0101 0011
0101 0011
FRCR
FCR
Rev. 1.40
---0 ---0
---0 ---0
---0 ---0
0000 0000
0000 0000
0000 0000
89
0101 0011 uuuu uuuu 0101 0011
---0 ---0
---u ---u
---0 ---0
0000 0000 uuuu uuuu 0000 0000
0101 0011
---0 ---0
0000 0000
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
Register
FARL
WDT Time-out/
RES Reset/
Reset
WDTC Software LVRC Software RES Reset
(HALT)
(Power On) Reset (Normal Reset (Normal
Operation)
Operation)
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
WDT
Time-out
(HALT)*
USB-reset USB-reset
(Normal)
(HALT)
uuuu uuuu
xxxx xxxx
xxxx xxxx
FARH
---- xxxx
---- xxxx
---- xxxx
---- xxxx
---- uuuu
---- xxxx
---- xxxx
FD0L
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
xxxx xxxx
xxxx xxxx
FD0H
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
xxxx xxxx
xxxx xxxx
FD1L
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
xxxx xxxx
xxxx xxxx
FD1H
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
xxxx xxxx
xxxx xxxx
FD2L
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
xxxx xxxx
xxxx xxxx
FD2H
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
xxxx xxxx
xxxx xxxx
FD3L
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
xxxx xxxx
xxxx xxxx
FD3H
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
xxxx xxxx
xxxx xxxx
I2CTOC
0000 0000
0000 0000
0000 0000
0000 0000 uuuu uuuu 0000 0000
0000 0000
SIMC0
1110 000-
1110 000-
1110 000-
1110 000-
1110 000-
1110 000-
SIMC1
1000 0001
1000 0001
1000 0001
1000 0001 uuuu uuuu 1000 0001
1000 0001
SIMD
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
SIMA/SIMC2 0000 0000
0000 0000 uuuu uuuu 0000 0000
0000 0000
0000 0000
0000 0000
SPIAC0
111- --0-
111- --0-
111- --0-
111- --0-
SPIAC1
--00 0000
--00 0000
--00 0000
SPIAD
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuuuuu uuuu
uuu- --u-
111- --0-
111- --0-
--00 0000
--uu uuuu
--00 0000
--00 0000
xxxx xxxx
uuuu uuuu
xxxx xxxx
xxxx xxxx
0-00 ---0
u-uu ---u
0-00 ---0
SBSC
0-00 ---0
0-00 ---0
0-00 ---0
PAWU
0000 0000
0000 0000
0000 0000
0000 0000 uuuu uuuu 0000 0000
0000 0000
PADIR
0000 0000
0000 0000
0000 0000
0000 0000 uuuu uuuu 0000 0000
0000 0000
PAPU
0000 0000
0000 0000
0000 0000
0000 0000 uuuu uuuu 0000 0000
0000 0000
PXPU
-000 ---0
-000 ---0
-000 ---0
-000 ---0
-uuu ---u
-000 ---0
0-00 ---0
-000 ---0
PAOI
0000 0000
0000 0000
0000 0000
0000 0000 uuuu uuuu 0000 0000
0000 0000
PSLEW
00-- 0000
00-- 0000
00-- 0000
00-- 0000
uu-- uuuu
00-- 0000
00-- 0000
PXWU
-000 ---0
-000 ---0
-000 ---0
-000 ---0
-uuu ---u
-000 ---0
-000 ---0
PXOI
-000 ---0
-000 ---0
-000 ---0
-000 ---0
-uuu ---u
-000 ---0
-000 ---0
CP0C
1000 0--1
1000 0--1
1000 0--1
1000 0--1
uuuu u--u
1000 0--1
1000 0--1
---1 ---1
---1 ---1
---1 ---1
---1 ---1
---u ---u
---1 ---1
---1 ---1
TMPC0
TMPC1
--0- --0-
--0- --0-
--0- --0-
--0- --0-
--u- --u-
--0- --0-
--0- --0-
TM0C0
0000 0---
0000 0---
0000 0---
0000 0---
uuuu u---
0000 0---
0000 0---
TM0C1
0000 0000
0000 0000
0000 0000
0000 0000 uuuu uuuu 0000 0000
0000 0000
TM0DL
0000 0000
0000 0000
0000 0000
0000 0000 uuuu uuuu 0000 0000
0000 0000
TM0DH
0000 0000
0000 0000
0000 0000
0000 0000 uuuu uuuu 0000 0000
0000 0000
TM0AL
0000 0000
0000 0000
0000 0000
0000 0000 uuuu uuuu 0000 0000
0000 0000
TM0AH
0000 0000
0000 0000
0000 0000
0000 0000 uuuu uuuu 0000 0000
0000 0000
TM0RP
0000 0000
0000 0000
0000 0000
0000 0000 uuuu uuuu 0000 0000
0000 0000
TM1C0
0000 0000
0000 0000
0000 0000
0000 0000 uuuu uuuu 0000 0000
0000 0000
TM1C1
0000 0000
0000 0000
0000 0000
0000 0000 uuuu uuuu 0000 0000
0000 0000
TM1DL
0000 0000
0000 0000
0000 0000
0000 0000 uuuu uuuu 0000 0000
0000 0000
Rev. 1.40
90
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
Register
WDT Time-out/
RES Reset/
Reset
WDTC Software LVRC Software RES Reset
(HALT)
(Power On) Reset (Normal Reset (Normal
Operation)
Operation)
---- --00
---- --00
---- --00
TM1AL
0000 0000
0000 0000
0000 0000
TM1AH
---- --00
---- --00
---- --00
TM2C0
0000 0000
0000 0000
0000 0000
0000 0000 uuuu uuuu 0000 0000
0000 0000
TM2C1
0000 0000
0000 0000
0000 0000
0000 0000 uuuu uuuu 0000 0000
0000 0000
TM2DL
0000 0000
0000 0000
0000 0000
0000 0000 uuuu uuuu 0000 0000
0000 0000
TM2DH
---- --00
---- --00
---- --00
TM2AL
0000 0000
0000 0000
0000 0000
TM2AH
---- --00
---- --00
---- --00
TM3C0
0000 0000
0000 0000
0000 0000
0000 0000 uuuu uuuu 0000 0000
0000 0000
TM3C1
0000 0000
0000 0000
0000 0000
0000 0000 uuuu uuuu 0000 0000
0000 0000
TM3DL
0000 0000
0000 0000
0000 0000
0000 0000 uuuu uuuu 0000 0000
0000 0000
---- --00
---- --00
---- --00
TM3AL
0000 0000
0000 0000
0000 0000
TM3AH
USB_STAT
---- --uu
USB-reset USB-reset
(Normal)
(HALT)
TM1DH
TM3DH
---- --00
WDT
Time-out
(HALT)*
---- --00
0000 0000 uuuu uuuu 0000 0000
---- --00
---- --00
---- --uu
---- --uu
---- --00
---- --00
0000 0000 uuuu uuuu 0000 0000
---- --00
---- --00
---- --uu
---- --uu
---- --00
---- --00
0000 0000 uuuu uuuu 0000 0000
---- --00
0000 0000
---- --00
---- --00
0000 0000
---- --00
---- --00
0000 0000
---- --00
---- --00
---- --00
---- --00
---- --uu
---- --00
---- --00
11xx 000x
uuxx uuux
uuxx uuux
uuxx uuux
uuxx uuux
uuxx uuux
uuxx uuux
---- uuuu
---- uuuu
UINT
---- 0000
---- uuuu
---- uuuu
---- uuuu
USC
1000 xxxx
uuuu xuux
uuuu xuux
uuuu xuux
uuuu xuux uuuu 0100
---- uuuu
uuuu 0100
USR
---- xxxx
---- uuuu
---- uuuu
---- uuuu
---- uuuu
---- uuuu
---- uuuu
UCC
000x 0-xx
uuuu u-uu
uuuu u-uu
uuuu u-uu
uuuu u-uu
uuu0 u-00
uuu0 u-00
AWR
xxxx xxxx
uuuu uuuu
uuuu uuuu
uuuu uuuu uuuu uuuu 0000 0000
0000 0000
STLI
---- xxxx
---- uuuu
---- uuuu
---- uuuu
---- uuuu
---- 0000
---- 0000
STLO
---- xxx-
---- uuu-
---- uuu-
---- uuu-
---- uuu-
---- 000-
---- 000-
SIES
xx-x xxxx
uu-x xuuu
uu-x xuuu
uu-x xuuu
uu-x xuuu
00-0 0000
00-0 0000
MISC
xxx- xxxx
xxu- uuxx
xxu- uuxx
xxu- uuxx
xxu- uuxx
000- 0000
000- 0000
UFIEN
---- 0000
---- uuuu
---- uuuu
---- uuuu
---- uuuu
---- uuuu
---- uuuu
FIFO0
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
FIFO1
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
FIFO2
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
FIFO3
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
UFOEN
---- 0000
---- uuuu
---- uuuu
---- uuuu
---- uuuu
---- uuuu
---- uuuu
uuuu uu--
UFC0
0000 00--
uuuu uu--
uuuu uu--
uuuu uu--
uuuu uu--
uuuu uu--
PAPS0
0000 0000
0000 0000
0000 0000
0000 0000 uuuu uuuu 0000 0000
0000 0000
PAPS1
0000 0000
0000 0000
0000 0000
0000 0000 uuuu uuuu 0000 0000
0000 0000
SYSC
000- -0--
000- -0--
000- -0--
000- -0--
uuu- -u--
000- -0--
000- -0--
CTRL
0--- -x00
0--- -x00
0--- -x00
0--- -x00
u--- -xuu
0--- -x00
0--- -x00
LVRC
0101 0101
0101 0101
0101 0101
0101 0101 uuuu uuuu 0101 0101
0101 0101
Note: "*" stands for "warm reset"
"-" not implement
"u" stands for "unchanged"
"x" stands for "unknown"
Rev. 1.40
91
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
The HT66FB550 register states are summarized below:
Register
WDT Time-out/
RES Reset/
Reset
WDTC Software LVRC Software
(Power On) Reset (Normal Reset (Normal
Operation)
Operation)
RES Reset
(HALT)
WDT
Time-out
(HALT)*
USB-reset USB-reset
(Normal)
(HALT)
MP0
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
xxxx xxxx
xxxx xxxx
MP1
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
xxxx xxxx
xxxx xxxx
ACC
xxxx xxxx
uuuu uuuu
uuuu uuuu
uuuu uuuu
uuuu uuuu uuuu uuuu uuuu uuuu
PCL
0000 0000
0000 0000
0000 0000
0000 0000
0000 0000 0000 0000 0000 0000
TBLP
xxxx xxxx
uuuu uuuu
uuuu uuuu
uuuu uuuu
uuuu uuuu uuuu uuuu uuuu uuuu
uuuu uuuu uuuu uuuu uuuu uuuu
TBLH
xxxx xxxx
uuuu uuuu
uuuu uuuu
uuuu uuuu
TBHP
---x xxxx
---u uuuu
---u uuuu
---u uuuu
---u uuuu
---u uuuu
---u uuuu
STATUS
--00 xxxx
--1u uuuu
--uu uuuu
--01 uuuu
--11 uuuu
--uu uuuu
--uu uuuu
---- -uuu
---- -000
BP
SMOD
---- -000
---- --000
---- -000
---- -000
0000 0011
0000 0011
0000 0011
0000 0011
uuuu uuuu 0000 0011
---- -000
0000 0011
INTEG
---- 0000
---- 0000
---- 0000
---- 0000
---- uuuu
---- 0000
---- 0000
LVDC
--00 -000
--00 -000
--00 -000
--00 -000
--uu -uuu
--00 -000
--00 -000
INTC0
-000 0000
-000 0000
-000 0000
-000 0000
-uuu uuuu
-000 0000
-000 0000
INTC1
0000 0000
0000 0000
0000 0000
0000 0000
uuuu uuuu 0000 0000 0000 0000
INTC2
0000 0000
0000 0000
0000 0000
0000 0000
uuuu uuuu 0000 0000 0000 0000
INTC3
-000 -000
-000 -000
-000 -000
-000 -000
-uuu -uuu
MFI0
0000 0000
0000 0000
0000 0000
0000 0000
uuuu uuuu 0000 0000 0000 0000
MFI1
0000 0000
0000 0000
0000 0000
0000 0000
uuuu uuuu 0000 0000 0000 0000
MFI2
-0-0 -0-0
-0-0 -0-0
-0-0 -0-0
-0-0 -0-0
-u-u -u-u
-0-0 -0-0
-0-0 -0-0
PA
1111 1111
1111 1111
1111 1111
1111 1111
uuuu uuuu
1111 1111
1111 1111
-000 -000
-000 -000
PAC
1111 1111
1111 1111
1111 1111
1111 1111
uuuu uuuu
1111 1111
1111 1111
PB
1111 1111
1111 1111
1111 1111
1111 1111
uuuu uuuu
1111 1111
1111 1111
PBC
1111 1111
1111 1111
1111 1111
1111 1111
uuuu uuuu
1111 1111
1111 1111
PC
1111 1111
1111 1111
1111 1111
1111 1111
uuuu uuuu
1111 1111
1111 1111
PCC
1111 1111
1111 1111
1111 1111
1111 1111
uuuu uuuu
1111 1111
1111 1111
PD
1111 1111
1111 1111
1111 1111
1111 1111
uuuu uuuu
1111 1111
1111 1111
PDC
1111 1111
1111 1111
1111 1111
1111 1111
uuuu uuuu
1111 1111
1111 1111
PE
--11 1101
--11 1101
--11 1101
--11 1101
--uu uuuu
--11 1101
--11 1101
PEC
--11 1111
--11 1111
--11 1111
--11 1111
--uu uuuu
--11 1111
--11 1111
ADRL
(ADRFS=0)
xxxx ----
xxxx ----
xxxx ----
xxxx ----
uuuu ----
xxxx ----
xxxx ----
ADRL
(ADRFS=1)
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
xxxx xxxx
xxxx xxxx
ADRH
(ADRFS=0)
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
xxxx xxxx
xxxx xxxx
ADRH
(ADRFS=1)
---- xxxx
---- xxxx
---- xxxx
---- xxxx
---- uuuu
---- xxxx
---- xxxx
ADCR0
0110 0000
0110 0000
0110 0000
0110 0000
uuuu uuuu 0110 0000
ADCR1
00-0 -000
00-0 -000
00-0 -000
00-0 -000
uu-u -uuu
00-0 -000
0110 0000
00-0 -000
ACER0
1111 1111
1111 1111
1111 1111
1111 1111
uuuu uuuu
1111 1111
1111 1111
ACER1
1111 1111
1111 1111
1111 1111
1111 1111
uuuu uuuu
1111 1111
1111 1111
WDTC
0101 0011
0101 0011
0101 0011
0101 0011
uuuu uuuu 0101 0011
0101 0011
TBC
0011 0111
0011 0111
0011 0111
0011 0111
uuuu uuuu
0011 0111
0011 0111
---0 ---0
---0 ---0
---0 ---0
---0 ---0
---u ---u
---0 ---0
---0 ---0
FCR
0000 0000
0000 0000
0000 0000
0000 0000
uuuu uuuu 0000 0000 0000 0000
FARL
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
FRCR
Rev. 1.40
92
xxxx xxxx
xxxx xxxx
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
Register
WDT Time-out/
RES Reset/
Reset
WDTC Software LVRC Software
(Power On) Reset (Normal Reset (Normal
Operation)
Operation)
RES Reset
(HALT)
WDT
Time-out
(HALT)*
USB-reset USB-reset
(Normal)
(HALT)
FARH
---x xxxx
---x xxxx
---x xxxx
---x xxxx
---u uuuu
---x xxxx
---x xxxx
FD0L
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
xxxx xxxx
xxxx xxxx
xxxx xxxx
FD0H
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
xxxx xxxx
FD1L
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
xxxx xxxx
xxxx xxxx
FD1H
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
xxxx xxxx
xxxx xxxx
FD2L
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
xxxx xxxx
xxxx xxxx
FD2H
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
xxxx xxxx
xxxx xxxx
FD3L
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
FD3H
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
I2CTOC
0000 0000
0000 0000
0000 0000
0000 0000
uuuu uuuu 0000 0000 0000 0000
SIMC0
1110 000-
1110 000-
1110 000-
1110 000-
uuuu uuu-
SIMC1
1000 0001
1000 0001
1000 0001
1000 0001
uuuu uuuu 1000 0001 1000 0001
1110 000-
SIMD
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
SIMA/SIMC2 0000 0000
0000 0000
0000 0000
0000 0000
uuuu uuuu 0000 0000 0000 0000
xxxx xxxx
1110 000xxxx xxxx
SPIAC0
111- --0-
111- --0-
111- --0-
111- --0-
uuu- --u-
111- --0-
111- --0-
SPIAC1
--00 0000
--00 0000
--00 0000
--00 0000
--uu uuuu
--00 0000
--00 0000
SPIAD
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
xxxx xxxx
xxxx xxxx
SBSC
0-00 ---0
0-00 ---0
0-00 ---0
0-00 ---0
u-uu ---u
0-00 ---0
0-00 ---0
PAWU
0000 0000
0000 0000
0000 0000
0000 0000
uuuu uuuu 0000 0000 0000 0000
PADIR
0000 0000
0000 0000
0000 0000
0000 0000
uuuu uuuu 0000 0000 0000 0000
PAPU
0000 0000
0000 0000
0000 0000
0000 0000
uuuu uuuu 0000 0000 0000 0000
PXPU
0000 0000
0000 0000
0000 0000
0000 0000
uuuu uuuu 0000 0000 0000 0000
PAOI
0000 0000
0000 0000
0000 0000
0000 0000
uuuu uuuu 0000 0000 0000 0000
PSLEW
0000 0000
0000 0000
0000 0000
0000 0000
uuuu uuuu 0000 0000 0000 0000
PXWU
0000 0000
0000 0000
0000 0000
0000 0000
uuuu uuuu 0000 0000 0000 0000
PXOI
0000 0000
0000 0000
0000 0000
0000 0000
uuuu uuuu 0000 0000 0000 0000
CP0C
1000 0--1
1000 0--1
1000 0--1
1000 0--1
uuuu u--u
1000 0--1
1000 0--1
CP1C
1000 0--1
1000 0--1
1000 0--1
1000 0--1
uuuu u--u
1000 0--1
1000 0--1
TMPC0
--01 --01
--01 --01
--01 --01
--01 --01
--uu --uu
--01 --01
--01 --01
TMPC1
--01 --01
--01 --01
--01 --01
--01 --01
--uu --uu
--01 --01
--01 --01
TM0C0
0000 0---
0000 0---
0000 0---
0000 0---
uuuu u---
0000 0---
0000 0---
TM0C1
0000 0000
0000 0000
0000 0000
0000 0000
uuuu uuuu 0000 0000 0000 0000
TM0DL
0000 0000
0000 0000
0000 0000
0000 0000
uuuu uuuu 0000 0000 0000 0000
TM0DH
0000 0000
0000 0000
0000 0000
0000 0000
uuuu uuuu 0000 0000 0000 0000
TM0AL
0000 0000
0000 0000
0000 0000
0000 0000
uuuu uuuu 0000 0000 0000 0000
TM0AH
0000 0000
0000 0000
0000 0000
0000 0000
uuuu uuuu 0000 0000 0000 0000
TM0RP
0000 0000
0000 0000
0000 0000
0000 0000
uuuu uuuu 0000 0000 0000 0000
TM1C0
0000 0000
0000 0000
0000 0000
0000 0000
uuuu uuuu 0000 0000 0000 0000
TM1C1
0000 0000
0000 0000
0000 0000
0000 0000
uuuu uuuu 0000 0000 0000 0000
TM1DL
0000 0000
0000 0000
0000 0000
0000 0000
uuuu uuuu 0000 0000 0000 0000
TM1DH
---- --00
---- --00
---- --00
---- --00
TM1AL
0000 0000
0000 0000
0000 0000
0000 0000
---- --uu
---- --00
---- --00
uuuu uuuu 0000 0000 0000 0000
TM1AH
---- --00
---- --00
---- --00
---- --00
TM2C0
0000 0000
0000 0000
0000 0000
0000 0000
uuuu uuuu 0000 0000 0000 0000
TM2C1
0000 0000
0000 0000
0000 0000
0000 0000
uuuu uuuu 0000 0000 0000 0000
TM2DL
0000 0000
0000 0000
0000 0000
0000 0000
uuuu uuuu 0000 0000 0000 0000
Rev. 1.40
93
---- --uu
---- --00
---- --00
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
Register
WDT Time-out/
RES Reset/
Reset
WDTC Software LVRC Software
(Power On) Reset (Normal Reset (Normal
Operation)
Operation)
RES Reset
(HALT)
TM2DH
---- --00
---- --00
---- --00
---- --00
TM2AL
0000 0000
0000 0000
0000 0000
0000 0000
WDT
Time-out
(HALT)*
---- --uu
USB-reset USB-reset
(Normal)
(HALT)
---- --00
---- --00
uuuu uuuu 0000 0000 0000 0000
TM2AH
---- --00
---- --00
---- --00
---- --00
TM3C0
0000 0000
0000 0000
0000 0000
0000 0000
uuuu uuuu 0000 0000 0000 0000
TM3C1
0000 0000
0000 0000
0000 0000
0000 0000
uuuu uuuu 0000 0000 0000 0000
uuuu uuuu 0000 0000 0000 0000
TM3DL
0000 0000
0000 0000
0000 0000
0000 0000
TM3DH
---- --00
---- --00
---- --00
---- --00
TM3AL
0000 0000
0000 0000
0000 0000
0000 0000
TM3AH
USB_STAT
---- --uu
---- --uu
---- --00
---- --00
---- --00
---- --00
uuuu uuuu 0000 0000 0000 0000
---- --00
---- --00
---- --00
---- --00
---- --uu
---- --00
---- --00
11xx 000x
uuxx uuux
uuxx uuux
uuxx uuux
uuxx uuux
uuxx uuux
uuxx uuux
--uu uuuu
--uu uuuu
UINT
--00 0000
--uu uuuu
--uu uuuu
--uu uuuu
--uu uuuu
USC
1000 xxxx
uuuu xuux
uuuu xuux
uuuu xuux
uuuu xuux uuuu 0100 uuuu 0100
USR
--xx xxxx
--uu uuuu
--uu uuuu
--uu uuuu
--uu uuuu
UCC
000x 0xxx
uuuu uuuu
uuuu uuuu
uuuu uuuu
uuuu uuuu uuu0 u000 uuu0 u000
--uu uuuu
--uu uuuu
AWR
xxxx xxxx
uuuu uuuu
uuuu uuuu
uuuu uuuu
uuuu uuuu 0000 0000 0000 0000
STLI
--xx xxxx
--uu uuuu
--uu uuuu
--uu uuuu
--uu uuuu
--00 0000
STLO
--xx xxx-
--uu uuu-
--uu uuu-
--uu uuu-
--uu uuu-
--00 000-
--00 000-
SIES
xx-x xxxx
uu-x xuuu
uu-x xuuu
uu-x xuuu
uu-x xuuu
00-0 0000
00-0 0000
MISC
xxxx xxxx
xxuu uuxx
xxuu uuxx
xxuu uuxx
xxuu uuxx
0000 0000 0000 0000
--00 0000
UFIEN
--00 0000
--uu uuuu
--uu uuuu
--uu uuuu
--uu uuuu
--uu uuuu
FIFO0
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
--uu uuuu
xxxx xxxx
FIFO1
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
FIFO2
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
FIFO3
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
FIFO4
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
FIFO5
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
UFOEN
--00 0000
--uu uuuu
--uu uuuu
--uu uuuu
--uu uuuu
--uu uuuu
--uu uuuu
UFC0
0000 00--
uuuu uu--
uuuu uu--
uuuu uu--
uuuu uu--
uuuu uu--
uuuu uu--
UFC1
---- 0000
---- uuuu
---- uuuu
---- uuuu
---- uuuu
---- uuuu
---- uuuu
PAPS0
0000 0000
0000 0000
0000 0000
0000 0000
uuuu uuuu 0000 0000 0000 0000
PAPS1
0000 0000
0000 0000
0000 0000
0000 0000
uuuu uuuu 0000 0000 0000 0000
SYSC
000- -0--
000- -0--
000- -0--
000- -0--
uuu- -u--
000- -0--
000- -0--
CTRL
0--- -x00
0--- -x00
0--- -x00
0--- -x00
u--- -xuu
0--- -x00
0--- -x00
LVRC
0101 0101
0101 0101
0101 0101
0101 0101
uuuu uuuu 0101 0101 0101 0101
Note: "*" stands for "warm reset"
"-" not implement
"u" stands for "unchanged"
"x" stands for "unknown"
Rev. 1.40
94
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
The HT66FB560 register states are summarized below:
Register
WDT Time-out/
RES Reset/
Reset
WDTC Software LVRC Software
(Power On) Reset (Normal Reset (Normal
Operation)
Operation)
RES Reset
(HALT)
WDT
Time-out
(HALT)*
USB-reset USB-reset
(Normal)
(HALT)
MP0
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
xxxx xxxx
xxxx xxxx
MP1
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
xxxx xxxx
xxxx xxxx
uuuu uuuu uuuu uuuu uuuu uuuu uuuu uuuu
ACC
xxxx xxxx
uuuu uuuu
uuuu uuuu
PCL
0000 0000
0000 0000
0000 0000
0000 0000 0000 0000 0000 0000 0000 0000
TBLP
xxxx xxxx
uuuu uuuu
uuuu uuuu
uuuu uuuu uuuu uuuu uuuu uuuu uuuu uuuu
TBLH
xxxx xxxx
uuuu uuuu
uuuu uuuu
uuuu uuuu uuuu uuuu uuuu uuuu uuuu uuuu
TBHP
--xx xxxx
--uu uuuu
--uu uuuu
--uu uuuu
--uu uuuu
--uu uuuu
--uu uuuu
STATUS
--00 xxxx
--1u uuuu
--uu uuuu
--01 uuuu
--11 uuuu
--uu uuuu
--uu uuuu
BP
--0- -000
--0- --000
--0- -000
--0- -000
--u- -uuu
--0- -000
0000 0011
0000 0011
0000 0011
SMOD
0000 0011 uuuu uuuu 0000 0011
--0- -000
0000 0011
INTEG
---- 0000
---- 0000
---- 0000
---- 0000
---- uuuu
---- 0000
---- 0000
LVDC
--00 -000
--00 -000
--00 -000
--00 -000
--uu -uuu
--00 -000
--00 -000
-uuu uuuu
-000 0000
-000 0000
INTC0
-000 0000
-000 0000
-000 0000
-000 0000
INTC1
0000 0000
0000 0000
0000 0000
0000 0000 uuuu uuuu 0000 0000 0000 0000
0000 0000 uuuu uuuu 0000 0000 0000 0000
INTC2
0000 0000
0000 0000
0000 0000
INTC3
-000 -000
-000 -000
-000 -000
-000 -000
MFI0
0000 0000
0000 0000
0000 0000
0000 0000 uuuu uuuu 0000 0000 0000 0000
MFI1
0000 0000
0000 0000
0000 0000
0000 0000 uuuu uuuu 0000 0000 0000 0000
MFI2
-0-0 -0-0
-0-0 -0-0
-0-0 -0-0
-0-0 -0-0
-u-u -u-u
-0-0 -0-0
-0-0 -0-0
PA
1111 1111
1111 1111
1111 1111
1111 1111
uuuu uuuu
1111 1111
1111 1111
-uuu -uuu
-000 -000
-000 -000
PAC
1111 1111
1111 1111
1111 1111
1111 1111
uuuu uuuu
1111 1111
1111 1111
PB
1111 1111
1111 1111
1111 1111
1111 1111
uuuu uuuu
1111 1111
1111 1111
PBC
1111 1111
1111 1111
1111 1111
1111 1111
uuuu uuuu
1111 1111
1111 1111
PC
1111 1111
1111 1111
1111 1111
1111 1111
uuuu uuuu
1111 1111
1111 1111
PCC
1111 1111
1111 1111
1111 1111
1111 1111
uuuu uuuu
1111 1111
1111 1111
PD
1111 1111
1111 1111
1111 1111
1111 1111
uuuu uuuu
1111 1111
1111 1111
PDC
1111 1111
1111 1111
1111 1111
1111 1111
uuuu uuuu
1111 1111
1111 1111
PE
--11 1101
--11 1101
--11 1101
--11 1101
--uu uuuu
--11 1101
--11 1101
PEC
--11 1111
--11 1111
--11 1111
--11 1111
--uu uuuu
--11 1111
--11 1111
PF
1111 1111
1111 1111
1111 1111
1111 1111
uuuu uuuu
1111 1111
1111 1111
PFC
1111 1111
1111 1111
1111 1111
1111 1111
uuuu uuuu
1111 1111
1111 1111
ADRL
(ADRFS=0)
xxxx ----
xxxx ----
xxxx ----
xxxx ----
uuuu ----
xxxx ----
xxxx ----
ADRL
(ADRFS=1)
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
xxxx xxxx
xxxx xxxx
ADRH
(ADRFS=0)
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
xxxx xxxx
xxxx xxxx
ADRH
(ADRFS=1)
---- xxxx
---- xxxx
---- xxxx
---- xxxx
---- uuuu
---- xxxx
---- xxxx
ADCR0
0110 0000
0110 0000
0110 0000
0110 0000 uuuu uuuu 0110 0000
ADCR1
00-0 -000
00-0 -000
00-0 -000
00-0 -000
uu-u -uuu
00-0 -000
0110 0000
00-0 -000
ACER0
1111 1111
1111 1111
1111 1111
1111 1111
uuuu uuuu
1111 1111
1111 1111
uuuu uuuu
ACER1
1111 1111
1111 1111
1111 1111
1111 1111
1111 1111
1111 1111
WDTC
0101 0011
0101 0011
0101 0011
0101 0011 uuuu uuuu 0101 0011
0101 0011
TBC
0011 0111
0011 0111
0011 0111
0011 0111
uuuu uuuu
0011 0111
0011 0111
---0 ---0
---0 ---0
---0 ---0
---0 ---0
---u ---u
---0 ---0
---0 ---0
FRCR
Rev. 1.40
95
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
Register
WDT Time-out/
RES Reset/
Reset
WDTC Software LVRC Software
(Power On) Reset (Normal Reset (Normal
Operation)
Operation)
RES Reset
(HALT)
WDT
Time-out
(HALT)*
USB-reset USB-reset
(Normal)
(HALT)
FCR
0000 0000
0000 0000
0000 0000
0000 0000 uuuu uuuu 0000 0000 0000 0000
FARL
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
xxxx xxxx
FARH
--xx xxxx
--xx xxxx
--xx xxxx
--xx xxxx
--uu uuuu
--xx xxxx
--xx xxxx
FD0L
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
xxxx xxxx
xxxx xxxx
FD0H
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
xxxx xxxx
xxxx xxxx
xxxx xxxx
FD1L
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
xxxx xxxx
xxxx xxxx
FD1H
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
xxxx xxxx
xxxx xxxx
FD2L
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
xxxx xxxx
xxxx xxxx
FD2H
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
xxxx xxxx
xxxx xxxx
FD3L
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
xxxx xxxx
xxxx xxxx
uuuu uuuu
xxxx xxxx
xxxx xxxx
FD3H
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
I2CTOC
0000 0000
0000 0000
0000 0000
0000 0000 uuuu uuuu 0000 0000 0000 0000
SIMC0
1110 000-
1110 000-
1110 000-
1110 000-
SIMC1
1000 0001
1000 0001
1000 0001
1000 0001 uuuu uuuu 1000 0001 1000 0001
uuuu uuu-
SIMD
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
SIMA/SIMC2 0000 0000
0000 0000
0000 0000
0000 0000 uuuu uuuu 0000 0000 0000 0000
uuuu uuuu
1110 000xxxx xxxx
1110 000xxxx xxxx
SPIAC0
111- --0-
111- --0-
111- --0-
111- --0-
uuu- --u-
111- --0-
111- --0-
SPIAC1
--00 0000
--00 0000
--00 0000
--00 0000
--uu uuuu
--00 0000
--00 0000
SPIAD
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
xxxx xxxx
xxxx xxxx
0-00 ---0
u-uu ---u
0-00 ---0
0-00 ---0
SBSC
0-00 ---0
0-00 ---0
0-00 ---0
PAWU
0000 0000
0000 0000
0000 0000
0000 0000 uuuu uuuu 0000 0000 0000 0000
PADIR
0000 0000
0000 0000
0000 0000
0000 0000 uuuu uuuu 0000 0000 0000 0000
PAPU
0000 0000
0000 0000
0000 0000
0000 0000 uuuu uuuu 0000 0000 0000 0000
PXPU
0000 0000
0000 0000
0000 0000
0000 0000 uuuu uuuu 0000 0000 0000 0000
PAOI
0000 0000
0000 0000
0000 0000
0000 0000 uuuu uuuu 0000 0000 0000 0000
PSLEW
0000 0000
0000 0000
0000 0000
0000 0000 uuuu uuuu 0000 0000 0000 0000
PXWU
0000 0000
0000 0000
0000 0000
0000 0000 uuuu uuuu 0000 0000 0000 0000
0000 0000 uuuu uuuu 0000 0000 0000 0000
PXOI
0000 0000
0000 0000
0000 0000
PFPU
0000 0000
0000 0000
0000 0000
0000 0000 uuuu uuuu 0000 0000 0000 0000
PFWU
0000 0000
0000 0000
0000 0000
0000 0000 uuuu uuuu 0000 0000 0000 0000
CP0C
1000 0--1
1000 0--1
1000 0--1
1000 0--1
uuuu u--u
1000 0--1
1000 0--1
CP1C
1000 0--1
1000 0--1
1000 0--1
1000 0--1
uuuu u--u
1000 0--1
1000 0--1
TMPC0
--01 --01
--01 --01
--01 --01
--01 --01
--uu --uu
--01 --01
--01 --01
TMPC1
--01 --01
--01 --01
--01 --01
--01 --01
--uu --uu
--01 --01
--01 --01
0000 0---
uuuu u---
0000 0---
0000 0---
TM0C0
0000 0---
0000 0---
0000 0---
TM0C1
0000 0000
0000 0000
0000 0000
0000 0000 uuuu uuuu 0000 0000 0000 0000
0000 0000 uuuu uuuu 0000 0000 0000 0000
TM0DL
0000 0000
0000 0000
0000 0000
TM0DH
0000 0000
0000 0000
0000 0000
0000 0000 uuuu uuuu 0000 0000 0000 0000
TM0AL
0000 0000
0000 0000
0000 0000
0000 0000 uuuu uuuu 0000 0000 0000 0000
TM0AH
0000 0000
0000 0000
0000 0000
0000 0000 uuuu uuuu 0000 0000 0000 0000
TM1C0
0000 0000
0000 0000
0000 0000
0000 0000 uuuu uuuu 0000 0000 0000 0000
TM1C1
0000 0000
0000 0000
0000 0000
0000 0000 uuuu uuuu 0000 0000 0000 0000
TM1DL
0000 0000
0000 0000
0000 0000
0000 0000 uuuu uuuu 0000 0000 0000 0000
TM1DH
---- --00
---- --00
---- --00
TM1AL
0000 0000
0000 0000
0000 0000
TM1AH
---- --00
---- --00
---- --00
Rev. 1.40
96
---- --00
---- --uu
---- --00
---- --00
0000 0000 uuuu uuuu 0000 0000 0000 0000
---- --00
---- --uu
---- --00
---- --00
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
Register
WDT Time-out/
RES Reset/
Reset
WDTC Software LVRC Software
(Power On) Reset (Normal Reset (Normal
Operation)
Operation)
RES Reset
(HALT)
WDT
Time-out
(HALT)*
USB-reset USB-reset
(Normal)
(HALT)
TM2C0
0000 0000
0000 0000
0000 0000
0000 0000 uuuu uuuu 0000 0000 0000 0000
TM2C1
0000 0000
0000 0000
0000 0000
0000 0000 uuuu uuuu 0000 0000 0000 0000
TM2DL
0000 0000
0000 0000
0000 0000
0000 0000 uuuu uuuu 0000 0000 0000 0000
TM2DH
---- --00
---- --00
---- --00
TM2AL
0000 0000
0000 0000
0000 0000
TM2AH
---- --00
---- --00
---- --00
TM3C0
0000 0000
0000 0000
0000 0000
---- --00
---- --uu
---- --00
---- --00
0000 0000 uuuu uuuu 0000 0000 0000 0000
---- --00
---- --uu
---- --00
---- --00
0000 0000 uuuu uuuu 0000 0000 0000 0000
TM3C1
0000 0000
0000 0000
0000 0000
0000 0000 uuuu uuuu 0000 0000 0000 0000
TM3DL
0000 0000
0000 0000
0000 0000
0000 0000 uuuu uuuu 0000 0000 0000 0000
TM3DH
---- --00
---- --00
---- --00
TM3AL
0000 0000
0000 0000
0000 0000
TM3AH
---- --00
---- --00
---- --00
---- --00
---- --uu
---- --00
---- --00
0000 0000 uuuu uuuu 0000 0000 0000 0000
---- --00
---- --uu
---- --00
---- --00
uuxx uuux
uuxx uuux
uuxx uuux
USB_STAT
11xx 000x
uuxx uuux
uuxx uuux
uuxx uuux
UINT
0000 0000
uuuu uuuu
uuuu uuuu
uuuu uuuu uuuu uuuu uuuu uuuu uuuu uuuu
USC
1000 xxxx
uuuu xuux
uuuu xuux
uuuu xuux
USR
xxxx xxxx
uuuu uuuu
uuuu uuuu
uuuu uuuu uuuu uuuu uuuu uuuu uuuu uuuu
uuuu xuux uuuu 0100 uuuu 0100
UCC
000x 0xxx
uuuu uuuu
uuuu uuuu
uuuu uuuu uuuu uuuu uuu0 u000 uuu0 u000
AWR
xxxx xxxx
uuuu uuuu
uuuu uuuu
uuuu uuuu uuuu uuuu 0000 0000 0000 0000
STLI
xxxx xxxx
uuuu uuuu
uuuu uuuu
uuuu uuuu uuuu uuuu 0000 0000 0000 0000
STLO
xxxx xxx-
uuuu uuu-
uuuu uuu-
uuuu uuu-
uuuu uuu-
0000 000-
0000 000-
SIES
xx-x xxxx
uu-x xuuu
uu-x xuuu
uu-x xuuu
uu-x xuuu
00-0 0000
00-0 0000
MISC
xxxx xxxx
xxuu uuxx
xxuu uuxx
xxuu uuxx
xxuu uuxx
0000 0000 0000 0000
uuuu uuuu uuuu uuuu uuuu uuuu uuuu uuuu
UFIEN
0000 0000
uuuu uuuu
uuuu uuuu
FIFO0
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
FIFO1
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
FIFO2
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
FIFO3
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
FIFO4
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
FIFO5
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
FIFO6
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
FIFO7
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
UFOEN
0000 0000
uuuu uuuu
uuuu uuuu
uuuu uuuu uuuu uuuu uuuu uuuu uuuu uuuu
UFC0
0000 00--
uuuu uu--
uuuu uu--
uuuu uu--
UFC1
0000 0000
uuuu uuuu
uuuu uuuu
uuuu uuuu uuuu uuuu uuuu uuuu uuuu uuuu
uuuu uu--
uuuu uu--
uuuu uu--
PAPS0
0000 0000
0000 0000
0000 0000
0000 0000 uuuu uuuu 0000 0000 0000 0000
PAPS1
0000 0000
0000 0000
0000 0000
0000 0000 uuuu uuuu 0000 0000 0000 0000
SYSC
000- -0--
000- -0--
000- -0--
000- -0--
uuu- -u--
000- -0--
000- -0--
CTRL
0--- -x00
0--- -x00
0--- -x00
0--- -x00
u--- -xuu
0--- -x00
0--- -x00
LVRC
0101 0101
0101 0101
0101 0101
0101 0101 uuuu uuuu 0101 0101 0101 0101
Note: "*" stands for "warm reset"
"-" not implement
"u" stands for "unchanged"
"x" stands for "unknown"
Rev. 1.40
97
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
Input/Output Ports
Holtek microcontrollers offer considerable flexibility on their I/O ports. With the input or output
designation of every pin fully under user program control, pull-high selections for all ports and
wake-up selections on certain pins, the user is provided with an I/O structure to meet the needs of a
wide range of application possibilities.
The devices provides bidirectional input/output lines labeled with port names PA~PF. These I/O
ports are mapped to the RAM Data Memory with specific addresses as shown in the Special Purpose
Data Memory table. All of these I/O ports can be used for input and output operations. For input
operation, these ports are non-latching, which means the inputs must be ready at the T2 rising edge
of instruction "MOV A, [m]", where m denotes the port address. For output operation, all the data is
latched and remains unchanged until the output latch is rewritten.
I/O Register List
• HT66FB540
Bit
Register
Name
7
6
5
4
3
2
1
0
PAWU
D7
D6
D5
D4
D3
D2
D1
D0
PAPU
D7
D6
D5
D4
D3
D2
D1
D0
PA
D7
D6
D5
D4
D3
D2
D1
D0
PAC
D7
D6
D5
D4
D3
D2
D1
D0
PADIR
D7
D6
D5
D4
D3
D2
D1
D0
D7
D6
D5
D4
D3
D2
D1
D0
—
—
PBSLEW1
PBSLEW0
PASLEW1
PASLEW0
PAOI
PSLEW
PDSLEW1 PDSLEW0
PXWU
PEHWU
PELWU
PDHWU
PDLWU
—
—
PBHWU
PBLWU
PXPU
PEHPU
PELPU
PDHPU
PDLPU
—
—
PBHPU
PBLPU
PXOI
PEHI
PELI
PDHI
PDLI
—
—
PBHI
PBLI
PAPS0
PA3S1
PA3S0
PA2S1
PA2S0
PA1S1
PA1S0
PA0S1
PA0S0
PAPS1
PA7S1
PA7S0
PA6S1
PA6S0
PA5S1
PA5S0
PA4S1
PA4S0
PB
—
D6
D5
D4
D3
D2
D1
D0
PBC
—
D6
D5
D4
D3
D2
D1
D0
PD
—
—
D5
D4
D3
D2
D1
D0
PDC
—
—
D5
D4
D3
D2
D1
D0
PE
—
—
—
D4
D3
D2
D1
D0
PEC
—
—
—
D4
D3
D2
D1
D0
Rev. 1.40
98
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
• HT66FB542
Register
Name
Bit
7
6
5
4
3
2
1
0
PAWU
D7
D6
D5
D4
D3
D2
D1
D0
PAPU
D7
D6
D5
D4
D3
D2
D1
D0
PA
D7
D6
D5
D4
D3
D2
D1
D0
PAC
D7
D6
D5
D4
D3
D2
D1
D0
PADIR
D7
D6
D5
D4
D3
D2
D1
D0
PAOI
D7
D6
D5
D4
D3
D2
D1
D0
PSLEW
—
—
PBSLEW1
PBSLEW0
PASLEW1
PASLEW0
PXWU
PDSLEW1 PDSLEW0
—
PELWU
PDHWU
PDLWU
—
—
—
PBLWU
PXPU
—
PELPU
PDHPU
PDLPU
—
—
—
PBLPU
PXOI
—
PELI
PDHI
PDLI
—
—
—
PBLI
PAPS0
PA3S1
PA3S0
PA2S1
PA2S0
PA1S1
PA1S0
PA0S1
PA0S0
PAPS1
PA7S1
PA7S0
PA6S1
PA6S0
PA5S1
PA5S0
PA4S1
PA4S0
PB
—
—
—
—
D3
D2
D1
D0
PBC
—
—
—
—
D3
D2
D1
D0
PD
—
—
—
D4
—
D2
D1
D0
PDC
—
—
—
D4
—
D2
D1
D0
PE
—
—
—
—
—
—
D1
D0
PEC
—
—
—
—
—
—
D1
D0
• HT66FB550
Bit
Register
Name
7
6
5
4
3
2
1
0
PAWU
D7
D6
D5
D4
D3
D2
D1
D0
PAPU
D7
D6
D5
D4
D3
D2
D1
D0
PA
D7
D6
D5
D4
D3
D2
D1
D0
PAC
D7
D6
D5
D4
D3
D2
D1
D0
PADIR
D7
D6
D5
D4
D3
D2
D1
D0
PAOI
D7
D6
D5
D4
D3
D2
D1
D0
PASLEW1
PASLEW0
PSLEW
PDSLEW1 PDSLEW0 PCSLEW1 PCSLEW0 PBSLEW1 PBSLEW0
PXWU
PEHWU
PELWU
PDHWU
PDLWU
PCHWU
PCLWU
PBHWU
PBLWU
PXPU
PEHPU
PELPU
PDHPU
PDLPU
PCHPU
PCLPU
PBHPU
PBLPU
PXOI
PEHI
PELI
PDHI
PDLI
PCHI
PCLI
PBHI
PBLI
PAPS0
PA3S1
PA3S0
PA2S1
PA2S0
PA1S1
PA1S0
PA0S1
PA0S0
PAPS1
PA7S1
PA7S0
PA6S1
PA6S0
PA5S1
PA5S0
PA4S1
PA4S0
PB
D7
D6
D5
D4
D3
D2
D1
D0
PBC
D7
D6
D5
D4
D3
D2
D1
D0
PC
D7
D6
D5
D4
D3
D2
D1
D0
PCC
D7
D6
D5
D4
D3
D2
D1
D0
PD
D7
D6
D5
D4
D3
D2
D1
D0
PDC
D7
D6
D5
D4
D3
D2
D1
D0
PE
—
—
D5
D4
D3
D2
D1
D0
PEC
—
—
D5
D4
D3
D2
D1
D0
Rev. 1.40
99
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
• HT66FB560
Bit
Register
Name
7
6
5
4
3
2
1
0
PAWU
D7
D6
D5
D4
D3
D2
D1
D0
PAPU
D7
D6
D5
D4
D3
D2
D1
D0
PA
D7
D6
D5
D4
D3
D2
D1
D0
PAC
D7
D6
D5
D4
D3
D2
D1
D0
PADIR
D7
D6
D5
D4
D3
D2
D1
D0
PAOI
D7
D6
D5
D4
D3
D2
D1
D0
PBSLEW0
PASLEW1
PASLEW0
PSLEW
PDSLEW1 PDSLEW0 PCSLEW1 PCSLEW0 PBSLEW1
PXWU
PEHWU
PELWU
PDHWU
PDLWU
PCHWU
PCLWU
PBHWU
PBLWU
PXPU
PEHPU
PELPU
PDHPU
PDLPU
PCHPU
PCLPU
PBHPU
PBLPU
PXOI
PEHI
PELI
PDHI
PDLI
PCHI
PCLI
PBHI
PBLI
PAPS0
PA3S1
PA3S0
PA2S1
PA2S0
PA1S1
PA1S0
PA0S1
PA0S0
PAPS1
PA7S1
PA7S0
PA6S1
PA6S0
PA5S1
PA5S0
PA4S1
PA4S0
PB
D7
D6
D5
D4
D3
D2
D1
D0
PBC
D7
D6
D5
D4
D3
D2
D1
D0
PC
D7
D6
D5
D4
D3
D2
D1
D0
PCC
D7
D6
D5
D4
D3
D2
D1
D0
PD
D7
D6
D5
D4
D3
D2
D1
D0
PDC
D7
D6
D5
D4
D3
D2
D1
D0
PE
—
—
D5
D4
D3
D2
D1
D0
PEC
—
—
D5
D4
D3
D2
D1
D0
PFWU
D7
D6
D5
D4
D3
D2
D1
D0
PFPU
D7
D6
D5
D4
D3
D2
D1
D0
PF
D7
D6
D5
D4
D3
D2
D1
D0
PFC
D7
D6
D5
D4
D3
D2
D1
D0
Rev. 1.40
100
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
Pull-high Resistors
Many product applications require pull-high resistors for their switch inputs usually requiring the
use of an external resistor. To eliminate the need for these external resistors, all I/O pins, when
configured as an input have the capability of being connected to an internal pull-high resistor.
These pull-high resistors are selected using registers, namely PAPU, PXPU and PFPU, and are
implemented using weak PMOS transistors. Note that the PA and PF pull-high resistors are
controlled by bits in the PAPU and PFPU registers, other than the PB, PC, PD, PE pull-high resistors
are controlled by nibble in the PXPU register.
PAPU Register
Bit
7
6
5
4
3
2
1
0
Name
D7
D6
D5
D4
D3
D2
D1
D0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
0
0
0
0
0
0
0
Bit 7~0
I/O PA bit 7~bit 0 Pull-High Control
0: Disable
1: Enable
PXPU Register
• HT66FB540
Bit
7
6
5
4
3
2
1
0
Name
PEHPU
PELPU
PDHPU
PDLPU
—
—
PBHPU
PBLPU
R/W
R/W
R/W
R/W
R/W
—
—
R/W
R/W
POR
0
0
0
0
—
—
0
0
Bit 7PEHPU: PE4 pin Pull-High control
0: Disable
1: Enable
Bit 6PELPU: PE3, PE2 and PE0 pins Pull-High control
0: Disable
1: Enable
Note that the PE1 pin has no pull-up resistor.
Bit 5PDHPU: PD7~PD4 pins Pull-High control
0: Disable
1: Enable
Bit 4PDLPU: PD3~PD0 pins Pull-High control
0: Disable
1: Enable
Bit 3~2
Unimplemented, read as "0"
Bit 1PBHPU: PB6~PB4 pins Pull-High control
0: Disable
1: Enable
Bit 0PBLPU: PB3~PB0 pins Pull-High control
0: Disable
1: Enable
Rev. 1.40
101
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
• HT66FB542
Bit
7
6
5
4
3
2
1
0
Name
—
PELPU
PDHPU
PDLPU
—
—
—
PBLPU
R/W
—
R/W
R/W
R/W
—
—
—
R/W
POR
—
0
0
0
—
—
—
0
Bit 7
Unimplemented, read as "0"
Bit 6PELPU: PE0 pin Pull-High Control
0: Disable
1: Enable
Note that the PE1 pin has no pull-up resistor.
Bit 5PDHPU: PD4 pin Pull-High Control
0: Disable
1: Enable
Bit 4PDLPU: PD2~PD0 pins Pull-High Control
0: Disable
1: Enable
Bit 3~1
Unimplemented, read as "0"
Bit 0PBLPU: PB3~PB0 pins Pull-High Control
0: Disable
1: Enable
• HT66FB550/HT66FB560
Bit
7
6
5
4
3
2
1
0
Name
PEHPU
PELPU
PDHPU
PDLPU
PCHPU
PCLPU
PBHPU
PBLPU
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
0
0
0
0
0
0
0
Bit 7PEHPU: PE5~PE4 pins Pull-High control
0: Disable
1: Enable
Bit 6PELPU: PE3, PE2 and PE0 pins Pull-High control
0: Disable
1: Enable
Note that the PE1 pin has no pull-up resistor.
Bit 5PDHPU: PD7~PD4 pins Pull-High control
0: Disable
1: Enable
Bit 4PDLPU: PD3~PD0 pins Pull-High control
0: Disable
1: Enable
Bit 3PCHPU: PC7~PC4 pins Pull-High control
0: Disable
1: Enable
Bit 2PCLPU: PC3~PC0 pins Pull-High control
0: Disable
1: Enable
Bit 1PBHPU: PB7~PB4 pins Pull-High control
0: Disable
1: Enable
Bit 0PBLPU: PB3~PB0 pins Pull-High control
0: Disable
1: Enable
Rev. 1.40
102
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
PFPU Register
• HT66FB560
Bit
7
6
5
4
3
2
1
0
Name
D7
D6
D5
D4
D3
D2
D1
D0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
0
0
0
0
0
0
0
Bit 7~0
I/O Port F bit 7~bit 0 Pull-High Control
0: Disable
1: Enable
Port Wake-up
The HALT instruction forces the microcontroller into the SLEEP or IDLE Mode which preserves
power, a feature that is important for battery and other low-power applications. Various methods
exist to wake-up the microcontroller, one of which is to change the logic condition on one of the
Port A~Port F pins from high to low. This function is especially suitable for applications that can be
woken up via external switches. Each pin on Port A~Port F can be selected by bits or nibble to have
this wake-up feature using the PAWU, PXWU and PFWU registers.
PAWU Register
Bit
7
6
5
4
3
2
1
0
Name
D7
D6
D5
D4
D3
D2
D1
D0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
0
0
0
0
0
0
0
Bit 7~0PAWU: Port A bit 7~bit 0 Wake-up Control
0: Disable
1: Enable
PXWU Register
• HT66FB540
Bit
7
6
5
4
3
2
1
0
Name
PEHWU
PELWU
PDHWU
PDLWU
—
—
PBHWU
PBLWU
R/W
R/W
R/W
R/W
R/W
—
—
R/W
R/W
POR
0
0
0
0
—
—
0
0
Bit 7PEHWU: PE4 pin Wake-up control
0: Disable
1: Enable
Bit 6PELWU: PE3, PE2,PE0 pins Wake-up control
0: Disable
1: Enable
Note that the PE1 pin has no wake-up function.
Bit 5PDHWU: PD7~PD4 pins Wake-up control
0: Disable
1: Enable
Bit 4PDLWU: PD3~PD0 pins Wake-up control
0: Disable
1: Enable
Bit3~2
Unimplemented, read as "0"
Bit 1PBHWU: PB6~PB4 pins Wake-up control
0: Disable
1: Enable
Rev. 1.40
103
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
Bit 0PBLWU: PB3~PB0 pins Wake-up control
0: Disable
1: Enable
• HT66FB542
Bit
7
6
5
4
3
2
1
0
Name
—
PELWU
PDHWU
PDLWU
—
—
—
PBLWU
R/W
—
R/W
R/W
R/W
—
—
—
R/W
POR
—
0
0
0
—
—
—
0
Bit 7
Unimplemented, read as "0"
Bit 6PELWU: PE0 pin Wake-up control
0: Disable
1: Enable
Note that the PE1 pin has no wake-up function.
Bit 5PDHWU: PD4 pin Wake-up control
0: Disable
1: Enable
Bit 4PDLWU: PD2~PD0 pins Wake-up control
0: Disable
1: Enable
Bit 3~1
Unimplemented, read as "0"
Bit 0PBLWU: PB3~PB0 pins Wake-up control
0: Disable
1: Enable
• HT66FB550/HT66FB560
Bit
7
6
5
4
3
2
1
0
Name
PEHWU
PELWU
PDHWU
PDLWU
PCHWU
PCLWU
PBHWU
PBLWU
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
0
0
0
0
0
0
0
Bit 7PEHWU: PE5, PE4 pins Wake-up control
0: Disable
1: Enable
Bit 6PELWU: PE3~PE2, PE0 pins Wake-up control
0: Disable
1: Enable
Note that the PE1 pin has no wake-up function.
Bit 5PDHWU: PD7~PD4 pins Wake-up control
0: Disable
1: Enable
Bit 4PDLWU: PD3~PD0 pins Wake-up control
0: Disable
1: Enable
Bit 3PCHWU: PC7~PC4 pins Wake-up control
0: Disable
1: Enable
Bit 2PCLWU: PC3~PC0 pins Wake-up control
0: Disable
1: Enable
Bit 1PBHWU: PB7~PB4 pins Wake-up control
0: Disable
1: Enable
Bit 0PBLWU: PB3~PB0 pins Wake-up control
0: Disable
1: Enable
Rev. 1.40
104
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
PFWU Register
• HT66FB560
Bit
7
6
5
4
3
2
1
0
Name
D7
D6
D5
D4
D3
D2
D1
D0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
0
0
0
0
0
0
0
Bit 7~0PFWU: Port F bit 7~bit 0 Wake-up Control
0: Disable
1: Enable
Port A Wake-up Polarity Control Register
The I/O port, PA, can be setup to have a choice of wake-up polarity using specific register. Each
pin on Port A can be selected individually to have this Wake-up polarity feature using the PADIR
register.
PADIR Register
Bit
7
6
5
4
3
2
1
0
Name
D7
D6
D5
D4
D3
D2
D1
D0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
0
0
0
0
0
0
0
Bit 7~0 PADIR: PA7~PA0 pins Wake-up edge control
0: Rising edge
1: Falling edge
I/O Port Control Registers
Each I/O port has its own control register known as PAC~PFC, to control the input/output
configuration. With this control register, each CMOS output or input can be reconfigured
dynamically under software control. Each pin of the I/O ports is directly mapped to a bit in its
associated port control register. For the I/O pin to function as an input, the corresponding bit of the
control register must be written as a "1". This will then allow the logic state of the input pin to be
directly read by instructions. When the corresponding bit of the control register is written as a "0",
the I/O pin will be setup as a CMOS output. If the pin is currently setup as an output, instructions
can still be used to read the output register. However, it should be noted that the program will in fact
only read the status of the output data latch and not the actual logic status of the output pin.
PAC Register
Bit
7
6
5
4
3
2
1
0
Name
D7
D6
D5
D4
D3
D2
D1
D0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
1
1
1
1
1
1
1
1
7
6
5
4
3
2
1
0
PBC Register
• HT66FB540
Bit
Rev. 1.40
Name
—
D6
D5
D4
D3
D2
D1
D0
R/W
—
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
—
1
1
1
1
1
1
1
105
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
• HT66FB542
Bit
7
6
5
4
3
2
1
0
Name
—
—
—
—
D3
D2
D1
D0
R/W
—
—
—
—
R/W
R/W
R/W
R/W
POR
—
—
—
—
1
1
1
1
• HT66FB550/HT66FB560
Bit
7
6
5
4
3
2
1
0
Name
D7
D6
D5
D4
D3
D2
D1
D0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
1
1
1
1
1
1
1
1
PCC Register
• HT66FB550/HT66FB560
Bit
7
6
5
4
3
2
1
0
Name
D7
D6
D5
D4
D3
D2
D1
D0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
1
1
1
1
1
1
1
1
PDC Register
• HT66FB540
Bit
7
6
5
4
3
2
1
0
Name
—
—
D5
D4
D3
D2
D1
D0
R/W
—
—
R/W
R/W
R/W
R/W
R/W
R/W
POR
—
—
1
1
1
1
1
1
• HT66FB542
Bit
7
6
5
4
3
2
1
0
Name
—
—
—
D4
—
D2
D1
D0
R/W
—
—
—
R/W
—
R/W
R/W
R/W
POR
—
—
—
1
—
1
1
1
• HT66FB550/HT66FB560
Rev. 1.40
Bit
7
6
5
4
3
2
1
0
Name
D7
D6
D5
D4
D3
D2
D1
D0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
1
1
1
1
1
1
1
1
106
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
PEC Register
• HT66FB540
Bit
7
6
5
4
3
2
1
0
Name
—
—
—
D4
D3
D2
D1
D0
R/W
—
—
—
R/W
R/W
R/W
R/W
R/W
POR
—
—
—
1
1
1
1
1
• HT66FB542
Bit
7
6
5
4
3
2
1
0
Name
—
—
—
—
—
—
D1
D0
R/W
—
—
—
—
—
—
R/W
R/W
POR
—
—
—
—
—
—
1
1
• HT66FB550/HT66FB560
Bit
7
6
5
4
3
2
1
0
Name
—
—
D5
D4
D3
D2
D1
D0
R/W
—
—
R/W
R/W
R/W
R/W
R/W
R/W
POR
—
—
1
1
1
1
1
1
7
6
5
4
3
2
1
0
PFC Register
• HT66FB560
Bit
Name
D7
D6
D5
D4
D3
D2
D1
D0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
1
1
1
1
1
1
1
1
Bit 7~0
I/O Port bit 7~bit 0 Input/Output Control
0: Output
1: Input
Note: The PE1 pin is input only.
I/O Output Current Control Registers
The I/O ports, PA~PE, can be setup to have a choice of high or low drive currents using specific
registers. Each pin on Port A can be selected individually to have this high output current feature
using the PAOI register. As for PB~PE, the output current must be selected by nibble using the
PXOI register. Note that the Port F is defaulted to have a low output current, the IOL is 4mA and IOH
is -4mA at VDD=5V.
PAOI Register
Bit
7
6
5
4
3
2
1
0
Name
D7
D6
D5
D4
D3
D2
D1
D0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
0
0
0
0
0
0
0
Bit 7~0PAOI: PA7~PA0 pins output current control (typical value, at VDD=5V)
0: IOL/IOH Low Current Drive
1: IOL/IOH High Current Drive
Rev. 1.40
107
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
PXOI Register
• HT66FB540
Bit
7
6
5
4
3
2
1
0
Name
PEHI
PELI
PDHI
PDLI
—
—
PBHI
PBLI
R/W
R/W
R/W
R/W
R/W
—
—
R/W
R/W
POR
0
0
0
0
—
—
0
0
Bit 7PEHI: PE4 pin output current control (typical value, at VDD=5V)
0: IOL/IOH Low Current Drive
1: IOL/IOH High Current Drive
Bit 6PELI: PE3~PE0 pins output current control (typical value, at VDD=5V)
0: IOL/IOH Low Current Drive
1: IOL/IOH High Current Drive
Bit 5PDHI: PD5~PD4 pins output current control (typical value, at VDD=5V)
0: IOL/IOH Low Current Drive
1: IOL/IOH High Current Drive
Bit 4PDLI: PD3~PD0 pins output current control (typical value, at VDD=5V)
0: IOL/IOH Low Current Drive
1: IOL/IOH High Current Drive
Bit 3~2
Unimplemented, read as "0"
Bit 1PBHI: PB6~PB4 pins output current control (typical value, at VDD=5V)
0: IOL/IOH Low Current Drive
1: IOL/IOH High Current Drive
Bit 0PBLI: PB3~PB0 pins output current control (typical value, at VDD=5V)
0: IOL/IOH Low Current Drive
1: IOL/IOH High Current Drive
• HT66FB542
Bit
7
6
5
4
3
2
1
0
Name
—
PELI
PDHI
PDLI
—
—
—
PBLI
R/W
—
R/W
R/W
R/W
—
—
—
R/W
POR
—
0
0
0
—
—
—
0
Bit 7
Unimplemented, read as "0"
Bit 6PELI: PE1~PE0 pins output current control (typical value, at VDD=5V)
0: IOL/IOH Low Current Drive
1: IOL/IOH High Current Drive
Bit 5PDHI: PD4 pin output current control (typical value, at VDD=5V)
0: IOL/IOH Low Current Drive
1: IOL/IOH High Current Drive
Bit 4PDLI: PD2~PD0 pins output current control (typical value, at VDD=5V)
0: IOL/IOH Low Current Drive
1: IOL/IOH High Current Drive
Bit 3~1
Unimplemented, read as "0"
Bit 0PBLI: PB3~PB0 pins output current control (typical value, at VDD=5V)
0: IOL/IOH Low Current Drive
1: IOL/IOH High Current Drive
Rev. 1.40
108
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
• HT66FB550/HT66FB560
Bit
7
6
5
4
3
2
1
0
Name
PEHI
PELI
PDHI
PDLI
PCHI
PCLI
PBHI
PBLI
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
0
0
0
0
0
0
0
Bit 7PEHI: PE5~PE4 pins output current control (typical value, at VDD=5V)
0: IOL/IOH Low Current Drive
1: IOL/IOH High Current Drive
Bit 6PELI: PE3~PE0 pins output current control (typical value, at VDD=5V)
0: IOL/IOH Low Current Drive
1: IOL/IOH High Current Drive
Bit 5PDHI: PD7~PD4 pins output current control (typical value, at VDD=5V)
0: IOL/IOH Low Current Drive
1: IOL/IOH High Current Drive
Bit 4PDLI: PD3~PD0 pins output current control (typical value, at VDD=5V)
0: IOL/IOH Low Current Drive
1: IOL/IOH High Current Drive
Bit 3PCHI: PC7~PC4 pins output current control (typical value, at VDD=5V)
0: IOL/IOH Low Current Drive
1: IOL/IOH High Current Drive
Bit 2PCLI: PC3~PC0 pins output current control (typical value, at VDD=5V)
0: IOL/IOH Low Current Drive
1: IOL/IOH High Current Drive
Bit 1PBHI: PB7~PB4 pins output current control (typical value, at VDD=5V)
0: IOL/IOH Low Current Drive
1: IOL/IOH High Current Drive
Bit 0PBLI: PB3~PB0 pins output current control (typical value, at VDD=5V)
0: IOL/IOH Low Current Drive
1: IOL/IOH High Current Drive
I/O Output Slew Rate Control Registers
The I/O ports, PA~PD, can be setup to have a choice of various slew rate using specific registers.
The slew rate must be selected by nibble using the PSLEW register. Note that the Port E and the Port
F are defaulted to have a fixed slew rate at 200ns.
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A/D Flash USB 8-Bit MCU with SPI
PSLEW Register
• HT66FB540/HT66FB542
Bit
7
6
Name PDSLEW1 PDSLEW0
5
4
3
2
1
0
—
—
R/W
R/W
R/W
—
—
PBSLEW1 PBSLEW0 PASLEW1 PASLEW0
R/W
R/W
R/W
R/W
POR
0
0
—
—
0
0
0
0
1
0
Bit 7~6
PDSLEW1, PDSLEW0: Port D output slew rate control
00: 200ns
01: 100ns
10: 50ns
11: No slew rate Bit 5~4
Unimplemented, read as "0"
Bit 3~2
PBSLEW1, PBSLEW0: Port B output slew rate control
00: 200ns
01: 100ns
10: 50ns
11: No slew rate
Bit 1~0
PASLEW1, PASLEW0: Port A output slew rate control
00: 200ns
01: 100ns
10: 50ns
11: No slew rate
• HT66FB550/HT66FB560
Bit
7
6
5
4
3
2
Name PDSLEW1 PDSLEW0 PCSLEW1 PCSLEW0 PBSLEW1 PBSLEW0 PASLEW1 PASLEW0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
0
0
0
0
0
0
0
Bit 7~6PDSLEW1, PDSLEW0: Port D output slew rate control
00: 200ns
01: 100ns
10: 50ns
11: No slew rate Bit 5~4PCSLEW1, PCSLEW0: Port C output slew rate control
00: 200ns
01: 100ns
10: 50ns
11: No slew rate
Rev. 1.40
Bit 3~2
PBSLEW1, PBSLEW0: Port B output slew rate control
00: 200ns
01: 100ns
10: 50ns
11: No slew rate
Bit 1~0
PASLEW1, PASLEW0: Port A output slew rate control
00: 200ns
01: 100ns
10: 50ns
11: No slew rate
110
September 18, 2015
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A/D Flash USB 8-Bit MCU with SPI
Port A Power Source Control Registers
Port A can be setup to have a choice of various power source using specific registers. Each pin on
Port A can be selected individually to have various power sources using the PAPS0 and PAPS1
registers.
PAPS0 Register
Bit
7
6
5
4
3
2
1
0
Name
PA3S1
PA3S0
PA2S1
PA2S0
PA1S1
PA1S0
PA0S1
PA0S0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
0
0
0
0
0
0
0
Bit 7~6
PA3S1, PA3S0: PA3 power supply control
00: VDD
01: VDD
10: VDDIO
11: V33O, 3.3V regulator output Bit 5~4PA2S1, PA2S0: PA2 power supply control
00: VDD
01: VDD
10: VDDIO
11: V33O, 3.3V regulator output Bit 3~2PA1S1, PA1S0: PA1 power supply control
00: VDD
01: VDD
10: VDDIO
11: V33O, 3.3V regulator output Bit 1~0PA0S1, PA0S0: PA0 power supply control
00: VDD
01: VDD
10: VDDIO
11: V33O, 3.3V regulator output PAPS1 Register
Bit
7
6
5
4
3
2
1
0
Name
PA7S1
PA7S0
PA6S1
PA6S0
PA5S1
PA5S0
PA4S1
PA4S0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
0
0
0
0
0
0
0
Bit 7~6PA7S1, PA7S0: PA7 power supply control
00: VDD
01: VDD
10: VDDIO
11: V33O, 3.3V regulator output
Bit 5~4PA6S1, PA6S0: PA6 power supply control
00: VDD
01: VDD
10: VDDIO
11: V33O, 3.3V regulator output
Bit 3~2PA5S1, PA5S0: PA5 power supply control
00: VDD
01: VDD
10: VDDIO
11: V33O, 3.3V regulator output Rev. 1.40
111
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A/D Flash USB 8-Bit MCU with SPI
Bit 1~0PA4S1, PA4S0: PA4 power supply control
00: VDD
01: VDD
10: VDDIO
11: V33O, 3.3V regulator output I/O Pin Structures
The accompanying diagrams illustrate the internal structures of some generic I/O pin types. As
the exact logical construction of the I/O pin will differ from these drawings, they are supplied as a
guide only to assist with the functional understanding of the I/O pins. The wide range of pin-shared
structures does not permit all types to be shown.
  
   Note: The PE1 pin is input only and has no pull-up resistor as well as wake-up function.
Generic Input/Output Structure
 €  
 ­
­
   
A/D Input/Output Structure
Rev. 1.40
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A/D Flash USB 8-Bit MCU with SPI
Programming Considerations
Within the user program, one of the first things to consider is port initialisation. After a reset, all of
the I/O data and port control registers will be set high. This means that all I/O pins will default to
an input state, the level of which depends on the other connected circuitry and whether pull-high
selections have been chosen. If the port control registers, PAC~PFC, are then programmed to setup
some pins as outputs, these output pins will have an initial high output value unless the associated
port data registers, PA~PF, are first programmed. Selecting which pins are inputs and which are
outputs can be achieved byte-wide by loading the correct values into the appropriate port control
register or by programming individual bits in the port control register using the "SET [m].i" and
"CLR [m].i" instructions. Note that when using these bit control instructions, a read-modify-write
operation takes place. The microcontroller must first read in the data on the entire port, modify it to
the required new bit values and then rewrite this data back to the output ports.
All Ports provide the wake-up function which can be set by individual pin in the Port A and Port F
while it has to be set by nibble pins in the Port B, Port C, Port D and Port E. When the devices are
in the SLEEP or IDLE Mode, various methods are available to wake the devices up. One of these is
a high to low transition of any of the Port pins. Single or multiple pins on Ports can be setup to have
this function.
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A/D Flash USB 8-Bit MCU with SPI
Timer Modules – TM
One of the most fundamental functions in any microcontroller devices are the ability to control and
measure time. To implement time related functions each device includes several Timer Modules,
abbreviated to the name TM. The TMs are multi-purpose timing units and serve to provide
operations such as Timer/Counter, Input Capture, Compare Match Output and Single Pulse Output
as well as being the functional unit for the generation of PWM signals. Each of the TMs has two
individual interrupts. The addition of input and output pins for each TM ensures that users are
provided with timing units with a wide and flexible range of features.
The common features of the different TM types are described here with more detailed information
provided in the individual Compact and Standard TM sections.
Introduction
The devices contain four TMs having a reference name of TM0, TM1, TM2 and TM3. Each
individual TM can be categorised as a certain type, namely Compact Type TM or Standard Type
TM. Although similar in nature, the different TM types vary in their feature complexity. The
common features to all of the Compact and Standard TMs will be described in this section. The
detailed operation regarding each of the TM types will be described in separate sections. The main
features and differences between the two types of TMs are summarised in the accompanying table.
CTM
STM
Timer/Counter
Function
√
√
I/P Capture
—
√
Compare Match Output
√
√
PWM Channels
1
1
Single Pulse Output
—
1
PWM Alignment
PWM Adjustment Period & Duty
Edge
Edge
Duty or Period
Duty or Period
TM Function Summary
Each device in the series contains a specific number of either Compact Type and Standard Type TM
units which are shown in the table together with their individual reference name, TM0~TM3.
Device
TM0
TM1
TM2
TM3
HT66FB540/HT66FB542/
HT66FB550/HT66FB560
16-bit STM
10-bit STM
10-bit CTM
10-bit CTM
TM Name/Type Reference
TM Operation
The different types of TM offer a diverse range of functions, from simple timing operations to
PWM signal generation. The key to understanding how the TM operates is to see it in terms of
a free running counter whose value is then compared with the value of pre-programmed internal
comparators. When the free running counter has the same value as the pre-programmed comparator,
known as a compare match situation, a TM interrupt signal will be generated which can clear the
counter and perhaps also change the condition of the TM output pin. The internal TM counter is
driven by a user selectable clock source, which can be an internal clock or an external pin.
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A/D Flash USB 8-Bit MCU with SPI
TM Clock Source
The clock source which drives the main counter in each TM can originate from various sources.
The selection of the required clock source is implemented using the TnCK2~TnCK0 bits in the TM
control registers. The clock source can be a ratio of the system clock fSYS or the internal high clock
fH, the fTBC clock source (the fL clock source for the HT66FB542) or the external TCKn pin. Note
that setting these bits to the value 101 will select an undefined clock input, in effect disconnecting
the TM clock source. The TCKn pin clock source is used to allow an external signal to drive the TM
as an external clock source or for event counting.
TM Interrupts
The Compact and Standard type TMs each have two internal interrupts, one for each of the internal
comparator A or comparator P, which generate a TM interrupt when a compare match condition
occurs. When a TM interrupt is generated it can be used to clear the counter and also to change the
state of the TM output pin.
TM External Pins
Each of the TMs, irrespective of what type, has one TM input pin, with the label TCKn. The TM
input pin, is essentially a clock source for the TM and is selected using the TnCK2~TnCK0 bits in
the TMnC0 register. This external TM input pin allows an external clock source to drive the internal
TM. This external TM input pin is shared with other functions but will be connected to the internal
TM if selected using the TnCK2~TnCK0 bits. The TM input pin can be chosen to have either a
rising or falling active edge.
The TMs each have one or two output pins with the label TPn. When the TM is in the Compare
Match Output Mode, these pins can be controlled by the TM to switch to a high or low level or to
toggle when a compare match situation occurs. The external TPn output pin is also the pin where
the TM generates the PWM output waveform. As the TM output pins are pin-shared with other
function, the TM output function must first be setup using registers. A single bit in one of the
registers determines if its associated pin is to be used as an external TM output pin or if it is to have
another function. The number of output pins for each TM type and devices are different, the details
are provided in the accompanying table.
All TM output pin names have a "_n" suffix. Pin names that include a "_0" or "_1" suffix indicate
that they are from a TM with multiple output pins. This allows the TM to generate a complimentary
output pair, selected using the I/O register data bits.
CTM
STM
HT66FB542
Device
TP2_1, TP3_1
TP0_0, TP1_0
HT66FB540
TP2_1, TP3_1
HT66FB550,
HT66FB560
TP2_0, TP3_0
TP2_1, TP3_1
TP0_0, TP0_1
TP1_0, TP1_1
Registers
TMPC0, TMPC1
TM Output Pins
Rev. 1.40
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A/D Flash USB 8-Bit MCU with SPI
TM Input/Output Pin Control Registers
Selecting to have a TM input/output or whether to retain its other shared function, is implemented
using two registers, with a single bit in each register corresponding to a TM input/output pin. Setting
the bit high will setup the corresponding pin as a TM input/output, if reset to zero the pin will retain
its original other function.
Registers
TMPC0
TMPC1
Bit
Device
7
6
5
4
3
2
1
0
HT66FB542
—
—
—
T1CP0
—
—
—
T0CP0
HT66FB540
HT66FB550
HT66FB560
—
—
T1CP1
T1CP0
—
—
T0CP1
T0CP0
HT66FB540
HT66FB542
—
—
T3CP1
—
—
—
T2CP1
—
HT66FB550
HT66FB560
—
—
T3CP1
T3CP0
—
—
T2CP1
T2CP0
TM Input/Output Pin Control Registers List
PA4 Out�ut Function
Out�ut
1
0
1
TM0
(STM)
0
PA4
Ca�tu�e In�ut
PA4/TP0_0
T0CP0
1
0
T0CP0
TCK In�ut
PA6/TCK0
HT66FB542 TM0 Function Pin Control Block Diagram
Note: The I/O register data bits shown are used for TM output inversion control.
Rev. 1.40
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A/D Flash USB 8-Bit MCU with SPI
HT66FB540/HT66FB550/HT66FB560 TM0 Function Pin Control Block Diagram
Note: (1) The I/O register data bits shown are used for TM output inversion control.
(2) In the Capture Input Mode, the TM pin control register must never enable more than one TM
input.
PA� Out�ut Function
Out�ut
1
0
1
TM1
(STM)
0
PA�
Ca�tu�e In�ut
PA�/TP1_0
T1CP0
1
0
T1CP0
TCK In�ut
PA0/TCK1
HT66FB542 TM1 Function Pin Control Block Diagram
Note: The I/O register data bits shown are used for TM output inversion control.
Rev. 1.40
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A/D Flash USB 8-Bit MCU with SPI
HT66FB540/HT66FB550/HT66FB560 TM1 Function Pin Control Block Diagram
Note: (1) The I/O register data bits shown are used for TM output inversion control.
(2) In the Capture Input Mode, the TM pin control register must never enable more than one TM
input.
HT66FB540/HT66FB542 TM2 Function Pin Control Block Diagram
Note: The I/O register data bits shown are used for TM output inversion control.
Rev. 1.40
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A/D Flash USB 8-Bit MCU with SPI
HT66FB550/HT66FB560 TM2 Function Pin Control Block Diagram
Note: The I/O register data bits shown are used for TM output inversion control.
HT66FB540/HT66FB542 TM3 Function Pin Control Block Diagram
Note: The I/O register data bits shown are used for TM output inversion control.
HT66FB550/HT66FB560 TM3 Function Pin Control Block Diagram
Note: The I/O register data bits shown are used for TM output inversion control.
Rev. 1.40
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A/D Flash USB 8-Bit MCU with SPI
TMPC0 Register
• HT66FB542
Bit
7
6
5
4
3
2
1
0
Name
—
—
—
T1CP0
—
—
—
T0CP0
R/W
—
—
—
R/W
—
—
—
R/W
POR
—
—
—
1
—
—
—
1
Bit 7~5
Unimplemented, read as "0"
Bit 4T1CP0: TP1_0 pin Control
0: Disable
1: Enable
Bit 3~1
Unimplemented, read as "0"
Bit 0T0CP0: TP0_0 pin Control
0: Disable
1: Enable
• HT66FB540/HT66FB550/HT66FB560
Bit
7
6
5
4
3
2
1
0
Name
—
—
T1CP1
T1CP0
—
—
T0CP1
T0CP0
R/W
—
—
R/W
R/W
—
—
R/W
R/W
POR
—
—
0
1
—
—
0
1
Bit 7~6
Unimplemented, read as "0"
Bit 5T1CP1: TP1_1 pin Control
0: Disable
1: Enable
Bit 4T1CP0: TP1_0 pin Control
0: Disable
1: Enable
Bit 3~2
Unimplemented, read as "0"
Bit 1T0CP1: TP0_1 pin Control
0: Disable
1: Enable
Bit 0T0CP0: TP0_0 pin Control
0: Disable
1: Enable
Rev. 1.40
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A/D Flash USB 8-Bit MCU with SPI
TMPC1 Register
• HT66FB540/HT66FB542
Bit
7
6
5
4
3
2
1
0
Name
—
—
T3CP1
—
—
—
T2CP1
—
R/W
—
—
R/W
—
—
—
R/W
—
POR
—
—
0
—
—
—
0
—
3
2
1
0
Bit 7~6
Unimplemented, read as "0"
Bit 5T3CP1: TP3_1 pin Control
0: Disable
1: Enable
Bit 4~2
Unimplemented, read as "0"
Bit 1T2CP1: TP2_1 pin Control
0: Disable
1: Enable
Bit 0
Unimplemented, read as "0"
• HT66FB550/HT66FB560
Bit
7
6
5
4
Name
—
—
T3CP1
T3CP0
—
—
T2CP1
T2CP0
R/W
—
—
R/W
R/W
—
—
R/W
R/W
POR
—
—
0
1
—
—
0
1
Bit 7~6
Unimplemented, read as "0"
Bit 5T3CP1: TP3_1 pin Control
0: Disable
1: Enable
Bit 4T3CP0: TP3_0 pin Control
0: Disable
1: Enable
Bit 3~2
Unimplemented, read as "0"
Bit 1T2CP1: TP2_1 pin Control
0: Disable
1: Enable
Bit 0T2CP0: TP2_0 pin Control
0: Disable
1: Enable
Rev. 1.40
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A/D Flash USB 8-Bit MCU with SPI
Programming Considerations
The TM Counter Registers and the Capture/Compare CCRA register, being either 10-bit or 16-bit,
all have a low and high byte structure. The high bytes can be directly accessed, but as the low bytes
can only be accessed via an internal 8-bit buffer, reading or writing to these register pairs must be
carried out in a specific way. The important point to note is that data transfer to and from the 8-bit
buffer and its related low byte only takes place when a write or read operation to its corresponding
high byte is executed.
TM Counte� Registe� (Read only)
TMxDL
TMxDH
�-�it
Buffe�
TMxAL
TMxAH
TM CCRA Registe� (Read/W�ite)
Data Bus
The following steps show the read and write procedures:
• Writing Data to CCRA
♦♦
Step 1. Write data to Low Byte TMxAL
––note that here data is only written to the 8-bit buffer.
♦♦
Step 2. Write data to High Byte TMxAH
––here data is written directly to the high byte registers and simultaneously data is latched
from the 8-bit buffer to the Low Byte registers.
• Reading Data from the Counter Registers and or CCRA
♦♦
Step 1. Read data from the High Byte TMxDH, TMxAH
––here data is read directly from the High Byte registers and simultaneously data is latched
from the Low Byte register into the 8-bit buffer.
♦♦
Step 2. Read data from the Low Byte TMxDL, TMxAL
––this step reads data from the 8-bit buffer.
As the CCRA register is implemented in the way shown in the following diagram and accessing the
register pair is carried out in a specific way described above, it is recommended to use the "MOV"
instruction to access the CCRA low byte register, named TMxAL, using the following access
procedures. Accessing the CCRA low byte register without following these access procedures will
result in unpredictable values.
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A/D Flash USB 8-Bit MCU with SPI
Compact Type TM – CTM
Although the simplest form of the two TM types, the Compact TM type still contains three operating
modes, which are Compare Match Output, Timer/Event Counter and PWM Output modes. The
Compact TM can also be controlled with an external input pin and can drive one or two external
output pins. These two external output pins can be the same signal or the inverse signal.
Name
TM No.
TM Input Pin
TM Output Pin
HT66FB540/
HT66FB542
CTM
10-bit CTM
2, 3
TCK2, TCK3
TP2_1, TP3_1,
HT66FB550/
HT66FB560
10-bit CTM
2, 3
TCK2, TCK3
TP2_0, TP2_1, TP3_0, TP3_1,
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Compact Type TM Block Diagram
Compact TM Operation
At its core is a 10-bit count-up counter which is driven by a user selectable internal or external clock
source. There are also two internal comparators with the names, Comparator A and Comparator P.
These comparators will compare the value in the counter with CCRP and CCRA registers. The
CCRP is three bits wide whose value is compared with the highest three bits in the counter while the
CCRA is the ten bits and therefore compares with all counter bits.
The only way of changing the value of the 10-bit counter using the application program, is to
clear the counter by changing the TnON bit from low to high. The counter will also be cleared
automatically by a counter overflow or a compare match with one of its associated comparators.
When these conditions occur, a TM interrupt signal will also usually be generated. The Compact
Type TM can operate in a number of different operational modes, can be driven by different clock
sources including an input pin and can also control an output pin. All operating setup conditions are
selected using relevant internal registers.
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A/D Flash USB 8-Bit MCU with SPI
Compact Type TM Register Description
Overall operation of the Compact TM is controlled using six registers. A read only register pair
exists to store the internal counter 10-bit value, while a read/write register pair exists to store the
internal 10-bit CCRA value. The remaining two registers are control registers which setup the
different operating and control modes as well as the three CCRP bits.
Bit
Register
Name
7
6
5
4
3
2
1
0
TMnC0
TnPAU
TnCK2
TnCK1
TnCK0
TnON
TnRP2
TnRP1
TnRP0
TMnC1
TnM1
TnM0
TnIO1
TnIO0
TnOC
TnPOL
TnDPX
TnCCLR
TMnDL
D7
D6
D5
D4
D3
D2
D1
D0
TMnDH
—
—
—
—
—
—
D9
D8
TMnAL
D7
D6
D5
D4
D3
D2
D1
D0
TMnAH
—
—
—
—
—
—
D9
D8
Compact TM Register List (n=2, 3)
TMnDL Register
Bit
7
6
5
4
3
2
1
0
Name
D7
D6
D5
D4
D3
D2
D1
D0
R/W
R
R
R
R
R
R
R
R
POR
0
0
0
0
0
0
0
0
Bit 7~0TMnDL: TMn Counter Low Byte Register bit 7~bit 0
TMn 10-bit Counter bit 7~bit 0
TMnDH Register
Bit
7
6
5
4
3
2
1
0
Name
—
—
—
—
—
—
D9
D8
R/W
—
—
—
—
—
—
R
R
POR
—
—
—
—
—
—
0
0
Bit 7~2
Unimplemented, read as "0"
Bit 1~0TMnDH: TMn Counter High Byte Register bit 1~bit 0
TMn 10-bit Counter bit 9~bit 8
TMnAL Register
Bit
7
6
5
4
3
2
1
0
Name
D7
D6
D5
D4
D3
D2
D1
D0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
0
0
0
0
0
0
0
Bit 7~0TMnAL: TMn CCRA Low Byte Register bit 7~bit 0
TMn 10-bit CCRA bit 7~bit 0
TMnAH Register
Bit
7
6
5
4
3
2
1
0
Name
—
—
—
—
—
—
D9
D8
R/W
—
—
—
—
—
—
R/W
R/W
POR
—
—
—
—
—
—
0
0
Bit 7~2
Unimplemented, read as "0"
Bit 1~0TMnAH: TMn CCRA High Byte Register bit 1~bit 0
TMn 10-bit CCRA bit 9~bit 8
Rev. 1.40
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A/D Flash USB 8-Bit MCU with SPI
TMnC0 Register
Bit
7
6
5
4
3
2
1
0
Name
TnPAU
TnCK2
TnCK1
TnCK0
TnON
TnRP2
TnRP1
TnRP0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
0
0
0
0
0
0
0
Bit 7TnPAU: TMn Counter Pause Control
0: Run
1: Pause
The counter can be paused by setting this bit high. Clearing the bit to zero restores
normal counter operation. When in a Pause condition the TM will remain powered up
and continue to consume power. The counter will retain its residual value when this bit
changes from low to high and resume counting from this value when the bit changes
to a low value again.
Bit 6~4TnCK2~TnCK0: Select TMn Counter clock
000: fSYS/4
001: fSYS
010: fH/16
011: fH/64
100: fTBC (HT66FB540/550/560), fL (HT66FB542)
101: Undefined
110: TCKn rising edge clock
111: TCKn falling edge clock
These three bits are used to select the clock source for the TMn. Selecting the
Reserved clock input will effectively disable the internal counter. The external pin
clock source can be chosen to be active on the rising or falling edge. The clock source
fSYS is the system clock, while fH and fTBC (fL) are other internal clocks, the details of
which can be found in the oscillator section.
Bit 3TnON: TMn Counter On/Off Control
0: Off
1: On
This bit controls the overall on/off function of the TMn. Setting the bit high enables
the counter to run, clearing the bit disables the TMn. Clearing this bit to zero will
stop the counter from counting and turn off the TMn which will reduce its power
consumption. When the bit changes state from low to high the internal counter value
will be reset to zero, however when the bit changes from high to low, the internal
counter will retain its residual value. If the TMn is in the Compare Match Output
Mode then the TMn output pin will be reset to its initial condition, as specified by the
TnOC bit, when the TnON bit changes from low to high.
Bit 2~0TnRP2~TnRP0: TMn CCRP 3-bit register, compared with the TMn Counter bit 9~bit 7
Comparator P Match Period
000: 1024 TMn clocks
001: 128 TMn clocks
010: 256 TMn clocks
011: 384 TMn clocks
100: 512 TMn clocks
101: 640 TMn clocks
110: 768 TMn clocks
111: 896 TMn clocks
These three bits are used to setup the value on the internal CCRP 3-bit register, which
are then compared with the internal counter’s highest three bits. The result of this
comparison can be selected to clear the internal counter if the TnCCLR bit is set to zero.
Setting the TnCCLR bit to zero ensures that a compare match with the CCRP values will
reset the internal counter. As the CCRP bits are only compared with the highest three
counter bits, the compare values exist in 128 clock cycle multiples. Clearing all three
bits to zero is in effect allowing the counter to overflow at its maximum value.
Rev. 1.40
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A/D Flash USB 8-Bit MCU with SPI
TMnC1 Register
Bit
7
6
5
4
3
2
1
0
Name
TnM1
TnM0
TnIO1
TnIO0
TnOC
TnPOL
TnDPX
TnCCLR
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
0
0
0
0
0
0
0
Bit 7~6TnM1~TnM0: Select TMn Operating Mode
00: Compare Match Output Mode
01: Undefined
10: PWM Mode
11: Timer/Counter Mode
These bits setup the required operating mode for the TM. To ensure reliable operation
the TM should be switched off before any changes are made to the TnM1 and TnM0
bits. In the Timer/Counter Mode, the TM output pin control must be disabled.
Bit 5~4TnIO1~TnIO0: Select TPn_0, TPn_1 output function
Compare Match Output Mode
00: No change
01: Output low
10: Output high
11: Toggle output
PWM Mode
00: PWM Output inactive state
01: PWM Output active state
10: PWM output
11: Undefined
Timer/counter Mode
unused
These two bits are used to determine how the TMn output pin changes state when a
certain condition is reached. The function that these bits select depends upon in which
mode the TMn is running. In the Compare Match Output Mode, the TnIO1 and TnIO0
bits determine how the TMn output pin changes state when a compare match occurs
from the Comparator A. The TMn output pin can be setup to switch high, switch
low or to toggle its present state when a compare match occurs from the Comparator
A. When the bits are both zero, then no change will take place on the output. The
initial value of the TMn output pin should be setup using the TnOC bit in the TMnC1
register. Note that the output level requested by the TnIO1 and TnIO0 bits must be
different from the initial value setup using the TnOC bit otherwise no change will
occur on the TMn output pin when a compare match occurs. After the TMn output pin
changes state it can be reset to its initial level by changing the level of the TnON bit
from low to high.
In the PWM Mode, the TnIO1 and TnIO0 bits determine how the TM output pin
changes state when a certain compare match condition occurs. The PWM output
function is modified by changing these two bits. It is necessary to only change the
values of the TnIO1 and TnIO0 bits only after the TMn has been switched off.
Unpredictable PWM outputs will occur if the TnIO1 and TnIO0 bits are changed when
the TM is running.
Rev. 1.40
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A/D Flash USB 8-Bit MCU with SPI
Bit 3TnOC: TPn_0, TPn_1 Output control bit
Compare Match Output Mode
0: Initial low
1: Initial high
PWM Mode
0: Active low
1: Active high
This is the output control bit for the TMn output pin. Its operation depends upon
whether TMn is being used in the Compare Match Output Mode or in the PWM Mode.
It has no effect if the TMn is in the Timer/Counter Mode. In the Compare Match
Output Mode it determines the logic level of the TMn output pin before a compare
match occurs. In the PWM Mode it determines if the PWM signal is active high or
active low.
Bit 2TnPOL: TPn_0, TPn_1 Output polarity Control
0: Non-invert
1: Invert
This bit controls the polarity of the TPn_0 or TPn_1 output pin. When the bit is set
high the TMn output pin will be inverted and not inverted when the bit is zero. It has
no effect if the TMn is in the Timer/Counter Mode.
Bit 1TnDPX: TMn PWM period/duty Control
0: CCRP - period; CCRA - duty
1: CCRP - duty; CCRA - period
This bit, determines which of the CCRA and CCRP registers are used for period and
duty control of the PWM waveform.
Bit 0TnCCLR: Select TMn Counter clear condition
0: TMn Comparator P match
1: TMn Comparator A match
This bit is used to select the method which clears the counter. Remember that the
Compact TMn contains two comparators, Comparator A and Comparator P, either of
which can be selected to clear the internal counter. With the TnCCLR bit set high,
the counter will be cleared when a compare match occurs from the Comparator A.
When the bit is low, the counter will be cleared when a compare match occurs from
the Comparator P or with a counter overflow. A counter overflow clearing method can
only be implemented if the CCRP bits are all cleared to zero. The TnCCLR bit is not
used in the PWM Mode.
Rev. 1.40
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A/D Flash USB 8-Bit MCU with SPI
Compact Type TM Operating Modes
The Compact Type TM can operate in one of three operating modes, Compare Match Output Mode,
PWM Mode or Timer/Counter Mode. The operating mode is selected using the TnM1 and TnM0
bits in the TMnC1 register.
Compare Match Output Mode
To select this mode, bits TnM1 and TnM0 in the TMnC1 register, should be set to "00" respectively.
In this mode once the counter is enabled and running it can be cleared by three methods. These are
a counter overflow, a compare match from Comparator A and a compare match from Comparator P.
When the TnCCLR bit is low, there are two ways in which the counter can be cleared. One is when a
compare match occurs from Comparator P, the other is when the CCRP bits are all zero which allows
the counter to overflow. Here both TnAF and TnPF interrupt request flags for the Comparator A and
Comparator P respectively, will both be generated.
If the TnCCLR bit in the TMnC1 register is high then the counter will be cleared when a compare
match occurs from Comparator A. However, here only the TnAF interrupt request flag will be
generated even if the value of the CCRP bits is less than that of the CCRA registers. Therefore when
TnCCLR is high no TnPF interrupt request flag will be generated. If the CCRA bits are all zero, the
counter will overflow when it reaches its maximum 10-bit, 3FF Hex, value, however here the TnAF
interrupt request flag will not be generated.
As the name of the mode suggests, after a comparison is made, the TM output pin will change
state. The TM output pin condition however only changes state when a TnAF interrupt request flag
is generated after a compare match occurs from Comparator A. The TnPF interrupt request flag,
generated from a compare match occurs from Comparator P, will have no effect on the TM output
pin. The way in which the TM output pin changes state are determined by the condition of the
TnIO1 and TnIO0 bits in the TMnC1 register. The TM output pin can be selected using the TnIO1
and TnIO0 bits to go high, to go low or to toggle from its present condition when a compare match
occurs from Comparator A. The initial condition of the TM output pin, which is setup after the
TnON bit changes from low to high, is setup using the TnOC bit. Note that if the TnIO1 and TnIO0
bits are zero then no pin change will take place.
Rev. 1.40
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A/D Flash USB 8-Bit MCU with SPI
Counte� Value
Counte� ove�flow
CCRP=0
0x3FF
TnCCLR = 0; TnM [1:0] = 00
CCRP > 0
Counte� clea�ed �y CCRP value
CCRP > 0
Counte�
Resta�t
Resu�e
CCRP
Pause
CCRA
�to�
Ti�e
TnON
TnPAU
TnPOL
CCRP Int.
Flag TnPF
CCRA Int.
Flag TnAF
TM O/P Pin
Out�ut �in set to
initial Level Low
if TnOC=0
Out�ut not affected �y TnAF
flag. Re�ains High until �eset
�y TnON �it
Out�ut Toggle with
TnAF flag
He�e TnIO [1:0] = 11
Toggle Out�ut select
Note TnIO [1:0] = 10
Active High Out�ut select
Out�ut Inve�ts
when TnPOL is high
Out�ut Pin
Reset to Initial value
Out�ut cont�olled �y
othe� �in-sha�ed function
Compare Match Output Mode – TnCCLR=0
Note: 1. With TnCCLR=0, a Comparator P match will clear the counter
2. The TM output pin is controlled only by the TnAF flag
3. The output pin is reset to its initial state by a TnON bit rising edge
Rev. 1.40
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A/D Flash USB 8-Bit MCU with SPI
Counter Value
TnCCLR = 1; TnM [1:0] = 00
CCRA = 0
Counter overflow
CCRA > 0 Counter cleared by CCRA value
0x3FF
CCRA=0
Resume
CCRA
Pause
Stop
Counter Restart
CCRP
Time
TnON
TnPAU
TnPOL
No TnAF flag
generated on
CCRA overflow
CCRA Int.
Flag TnAF
CCRP Int.
Flag TnPF
TnPF not
generated
Output does
not change
TM O/P Pin
Output pin set to
initial Level Low
if TnOC=0
Output not affected by
TnAF flag. Remains High
until reset by TnON bit
Output Toggle with
TnAF flag
Here TnIO [1:0] = 11
Toggle Output select
Note TnIO [1:0] = 10
Active High Output select
Output Inverts
when TnPOL is high
Output Pin
Reset to Initial value
Output controlled by
other pin-shared function
Compare Match Output Mode – TnCCLR=1
Note: 1. With TnCCLR=1, a Comparator A match will clear the counter
2. The TM output pin is controlled only by the TnAF flag
3. The output pin is reset to its initial state by a TnON bit rising edge
4. The TnPF flag is not generated when TnCCLR=1
Rev. 1.40
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A/D Flash USB 8-Bit MCU with SPI
Timer/Counter Mode
To select this mode, bits TnM1 and TnM0 in the TMnC1 register should be set to 11 respectively.
The Timer/Counter Mode operates in an identical way to the Compare Match Output Mode
generating the same interrupt flags. The exception is that in the Timer/Counter Mode the TM output
pin is not used. Therefore the above description and Timing Diagrams for the Compare Match
Output Mode can be used to understand its function. As the TM output pin is not used in this mode,
the pin can be used as a normal I/O pin or other pin-shared function.
PWM Output Mode
To select this mode, bits TnM1 and TnM0 in the TMnC1 register should be set to 10 respectively.
The PWM function within the TM is useful for applications which require functions such as motor
control, heating control, illumination control etc. By providing a signal of fixed frequency but
of varying duty cycle on the TM output pin, a square wave AC waveform can be generated with
varying equivalent DC RMS values.
As both the period and duty cycle of the PWM waveform can be controlled, the choice of generated
waveform is extremely flexible. In the PWM mode, the TnCCLR bit has no effect on the PWM
operation. Both of the CCRA and CCRP registers are used to generate the PWM waveform, one
register is used to clear the internal counter and thus control the PWM waveform frequency, while
the other one is used to control the duty cycle. Which register is used to control either frequency
or duty cycle is determined using the TnDPX bit in the TMnC1 register. The PWM waveform
frequency and duty cycle can therefore be controlled by the values in the CCRA and CCRP registers.
An interrupt flag, one for each of the CCRA and CCRP, will be generated when a compare match
occurs from either Comparator A or Comparator P. The TnOC bit in the TMnC1 register is used to
select the required polarity of the PWM waveform while the two TnIO1 and TnIO0 bits are used to
enable the PWM output or to force the TM output pin to a fixed high or low level. The TnPOL bit is
used to reverse the polarity of the PWM output waveform.
• CTM, PWM Mode, Edge-aligned Mode, TnDPX=0
CCRP
001b
010b
011b
100b
101b
110b
111b
000b
Period
128
256
384
512
640
768
896
1024
Duty
CCRA
If fSYS=16MHz, TM clock source is fSYS/4, CCRP=100b and CCRA=128,
The CTM PWM output frequency=(fSYS/4)/512=fSYS/2048=7.8125 kHz, duty=128/512=25%.
If the Duty value defined by the CCRA register is equal to or greater than the Period value, then the
PWM output duty is 100%.
• CTM, PWM Mode, Edge-aligned Mode, TnDPX=1
CCRP
001b
010b
011b
100b
128
256
384
512
Period
Duty
101b
110b
111b
000b
768
896
1024
CCRA
640
The PWM output period is determined by the CCRA register value together with the TM clock
while the PWM duty cycle is defined by the CCRP register value.
Rev. 1.40
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A/D Flash USB 8-Bit MCU with SPI
Counter Value
TnDPX = 0; TnM [1:0] = 10
Counter cleared
by CCRP
Counter Reset when
TnON returns high
CCRP
Pause Resume
CCRA
Counter Stop if
TnON bit low
Time
TnON
TnPAU
TnPOL
CCRA Int.
Flag TnAF
CCRP Int.
Flag TnPF
TM O/P Pin
(TnOC=1)
TM O/P Pin
(TnOC=0)
PWM Duty Cycle
set by CCRA
PWM Period
set by CCRP
PWM resumes
operation
Output controlled by
Output Inverts
other pin-shared function
when TnPOL = 1
PWM Mode – TnDPX=0
Note: 1. Here TnDPX=0 – Counter cleared by CCRP
2. A counter clear sets the PWM Period
3. The internal PWM function continues even when TnIO [1:0]=00 or 01
4. The TnCCLR bit has no influence on PWM operation
Rev. 1.40
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A/D Flash USB 8-Bit MCU with SPI
Counter Value
TnDPX = 1; TnM [1:0] = 10
Counter cleared
by CCRA
Counter Reset when
TnON returns high
CCRA
Pause Resume
CCRP
Counter Stop if
TnON bit low
Time
TnON
TnPAU
TnPOL
CCRP Int.
Flag TnPF
CCRA Int.
Flag TnAF
TM O/P Pin
(TnOC=1)
TM O/P Pin
(TnOC=0)
PWM Duty Cycle
set by CCRP
PWM Period
set by CCRA
PWM resumes
operation
Output controlled by
Output Inverts
other pin-shared function
when TnPOL = 1
PWM Mode – TnDPX=1
Note: 1. Here TnDPX=1 – Counter cleared by CCRA
2. A counter clear sets the PWM Period
3. The internal PWM function continues even when TnIO [1:0]=00 or 01
4. The TnCCLR bit has no influence on PWM operation
Rev. 1.40
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A/D Flash USB 8-Bit MCU with SPI
Standard Type TM – STM
The Standard Type TM contains five operating modes, which are Compare Match Output,
Timer/Event Counter, Capture Input, Single Pulse Output and PWM Output modes. The Standard
TM can also be controlled with an external input pin and can drive one or two external output pins.
STM
Name
TM No.
TM Input Pin
TM Output Pin
HT66FB542
16-bit STM
10-bit STM
0, 1
TCK0, TCK1
TP0_0, TP1_0
HT66FB540
HT66FB550
HT66FB560
16-bit STM
10-bit STM
0, 1
TCK0, TCK1
TP0_0, TP0_1
TP1_0, TP1_1
Standard TM Operation
There are two sizes of Standard TMs, one is 10-bit wide and the other is 16-bit wide. At the core is a
10 or 16-bit count-up counter which is driven by a user selectable internal or external clock source.
There are also two internal comparators with the names, Comparator A and Comparator P. These
comparators will compare the value in the counter with CCRP and CCRA registers. The CCRP
comparator is 3 or 8-bit wide whose value is compared with the highest 3 or 8 bits in the counter
while the CCRA is the ten or sixteen bits and therefore compares all counter bits.
The only way of changing the value of the 10 or 16-bit counter using the application program, is
to clear the counter by changing the TnON bit from low to high. The counter will also be cleared
automatically by a counter overflow or a compare match with one of its associated comparators.
When these conditions occur, a TM interrupt signal will also usually be generated. The Standard
Type TM can operate in a number of different operational modes, can be driven by different clock
sources including an input pin and can also control an output pin. All operating setup conditions are
selected using relevant internal registers.
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Standard Type TM Block Diagram
Rev. 1.40
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A/D Flash USB 8-Bit MCU with SPI
Standard Type TM Register Description
Overall operation of the Standard TM is controlled using a series of registers. A read only register
pair exists to store the internal counter 10 or 16-bit value, while a read/write register pair exists to
store the internal 10 or 16-bit CCRA value. The remaining two registers are control registers which
setup the different operating and control modes as well as the three or eight CCRP bits.
16-bit Standard TM Register List
Bit
Register
Name
7
6
5
4
3
2
1
0
TM0C0
T0PAU
T0CK2
T0CK1
T0CK0
T0ON
—
—
—
TM0C1
T0M1
T0M0
T0IO1
T0IO0
T0OC
T0POL
T0DPX
T0CCLR
TM0DL
D7
D6
D5
D4
D3
D2
D1
D0
TM0DH
D15
D14
D13
D12
D11
D10
D9
D8
TM0AL
D7
D6
D5
D4
D3
D2
D1
D0
TM0AH
D15
D14
D13
D12
D11
D10
D9
D8
TM0RP
D7
D6
D5
D4
D3
D2
D1
D0
• TM0C0 Register – 16-bit STM
Bit
7
6
5
4
3
2
1
0
Name
T0PAU
T0CK2
T0CK1
T0CK0
T0ON
—
—
—
R/W
R/W
R/W
R/W
R/W
R/W
—
—
—
POR
0
0
0
0
0
—
—
—
Bit 7T0PAU: TM0 Counter Pause Control
0: Run
1: Pause
The counter can be paused by setting this bit high. Clearing the bit to zero restores
normal counter operation. When in a Pause condition the TM will remain powered up
and continue to consume power. The counter will retain its residual value when this bit
changes from low to high and resume counting from this value when the bit changes
to a low value again.
Bit 6~4
Rev. 1.40
T0CK2, T0CK1, T0CK0: Select TM0 Counter clock
000: fSYS/4
001: fSYS
010: fH/16
011: fH/64
100: fTBC (HT66FB540/550/560), fL (HT66FB542)
101: Reserved
110: TCK0 rising edge clock
111: TCK0 falling edge clock
These three bits are used to select the clock source for the TM. Selecting the Reserved
clock input will effectively disable the internal counter. The external pin clock source
can be chosen to be active on the rising or falling edge. The clock source fSYS is the
system clock, while fH and fTBC (fL) are other internal clocks, the details of which can
be found in the oscillator section.
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A/D Flash USB 8-Bit MCU with SPI
Bit 3T0ON: TM0 Counter On/Off Control
0: Off
1: On
This bit controls the overall on/off function of the TM. Setting the bit high enables the
counter to run, clearing the bit disables the TM. Clearing this bit to zero will stop the
counter from counting and turn off the TM which will reduce its power consumption.
When the bit changes state from low to high the internal counter value will be reset to
zero, however when the bit changes from high to low, the internal counter will retain
its residual value until the bit returns high again. If the TM is in the Compare Match
Output Mode then the TM output pin will be reset to its initial condition, as specified
by the T0OC bit, when the T0ON bit changes from low to high.
Bit 2~0
Unimplemented, read as "0"
• TM0C1 Register – 16-bit STM
Bit
7
6
5
4
3
2
1
0
Name
T0M1
T0M0
T0IO1
T0IO0
T0OC
T0POL
T0DPX
T0CCLR
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
0
0
0
0
0
0
0
Bit 7~6T0M1~T0M0: Select TM0 Operating Mode
00: Compare Match Output Mode
01: Capture Input Mode
10: PWM Mode or Single Pulse Output Mode
11: Timer/Counter Mode
These bits setup the required operating mode for the TM. To ensure reliable operation
the TM should be switched off before any changes are made to the T0M1 and T0M0
bits. In the Timer/Counter Mode, the TM output pin control must be disabled.
Bit 5~4T0IO1~T0IO0: Select TP0_0, TP0_1 output function
Compare Match Output Mode
00: No change
01: Output low
10: Output high
11: Toggle output
PWM Mode/Single Pulse Output Mode
00: Force inactive state
01: Force active state
10: PWM output
11: Single pulse output
Capture Input Mode
00: Input capture at rising edge of TP0_0, TP0_1
01: Input capture at falling edge of TP0_0, TP0_1
10: Input capture at falling/rising edge of TP0_0, TP0_1
11: Input capture disabled
Timer/counter Mode:
Unused
These two bits are used to determine how the TM output pin changes state when a
certain condition is reached. The function that these bits select depends upon in which
mode the TM is running.
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In the Compare Match Output Mode, the T0IO1 and T0IO0 bits determine how the
TM output pin changes state when a compare match occurs from the Comparator A.
The TM output pin can be setup to switch high, switch low or to toggle its present
state when a compare match occurs from the Comparator A. When the bits are both
zero, then no change will take place on the output. The initial value of the TM output
pin should be setup using the T0OC bit in the TM0C1 register. Note that the output
level requested by the T0IO1 and T0IO0 bits must be different from the initial value
setup using the T0OC bit otherwise no change will occur on the TM output pin when
a compare match occurs. After the TM output pin changes state it can be reset to its
initial level by changing the level of the T0ON bit from low to high.
In the PWM Mode, the T0IO1 and T0IO0 bits determine how the TM output pin
changes state when a certain compare match condition occurs. The PWM output
function is modified by changing these two bits. It is necessary to only change
the values of the T0IO1 and T0IO0 bits only after the TM has been switched off.
Unpredictable PWM outputs will occur if the T0IO1 and T0IO0 bits are changed when
the TM is running.
Bit 3T0OC: TP0_0, TP0_1 Output control bit
Compare Match Output Mode
0: Initial low
1: Initial high
PWM Mode/Single Pulse Output Mode
0: Active low
1: Active high
This is the output control bit for the TM output pin. Its operation depends upon
whether TM is being used in the Compare Match Output Mode or in the PWM
Mode/Single Pulse Output Mode. It has no effect if the TM is in the Timer/Counter
Mode. In the Compare Match Output Mode it determines the logic level of the TM
output pin before a compare match occurs. In the PWM Mode it determines if the
PWM signal is active high or active low.
Bit 2T0POL: TP0_0, TP0_1 Output polarity Control
0: Non-invert
1: Invert
This bit controls the polarity of the TP0_0 or TP0_1 output pin. When the bit is set
high the TM output pin will be inverted and not inverted when the bit is zero. It has no
effect if the TM is in the Timer/Counter Mode.
Bit 1T0DPX: TM0 PWM period/duty Control
0: CCRP - period; CCRA - duty
1: CCRP - duty; CCRA - period
This bit, determines which of the CCRA and CCRP registers are used for period and
duty control of the PWM waveform.
Bit 0T0CCLR: Select TM0 Counter clear condition
0: TM0 Comparator P match
1: TM0 Comparator A match
This bit is used to select the method which clears the counter. Remember that the
Standard TM contains two comparators, Comparator A and Comparator P, either of
which can be selected to clear the internal counter. With the T0CCLR bit set high,
the counter will be cleared when a compare match occurs from the Comparator A.
When the bit is low, the counter will be cleared when a compare match occurs from
the Comparator P or with a counter overflow. A counter overflow clearing method can
only be implemented if the CCRP bits are all cleared to zero. The T0CCLR bit is not
used in the PWM, Single Pulse or Input Capture Mode.
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• TM0DL Register – 16-bit STM
Bit
7
6
5
4
3
2
1
0
Name
D7
D6
D5
D4
D3
D2
D1
D0
R/W
R
R
R
R
R
R
R
R
POR
0
0
0
0
0
0
0
0
Bit 7~0TM0DL: TM0 Counter Low Byte Register bit 7~bit 0
TM0 16-bit Counter bit 7~bit 0
• TM0DH Register – 16-bit STM
Bit
7
6
5
4
3
2
1
0
Name
D15
D14
D13
D12
D11
D10
D9
D8
R/W
R
R
R
R
R
R
R
R
POR
0
0
0
0
0
0
0
0
Bit 7~0TM0DH: TM0 Counter High Byte Register bit 7~bit 0
TM0 16-bit Counter bit 15~bit 8
• TM0AL Register – 16-bit STM
Bit
7
6
5
4
3
2
1
0
Name
D7
D6
D5
D4
D3
D2
D1
D0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
0
0
0
0
0
0
0
Bit 7~0TM0AL: TM0 CCRA Low Byte Register bit 7~bit 0
TM0 16-bit CCRA bit 7~bit 0
• TM0AH Register – 16-bit STM
Bit
7
6
5
4
3
2
1
0
Name
D15
D14
D13
D12
D11
D10
D9
D8
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
0
0
0
0
0
0
0
2
1
0
Bit 7~0TM0AH: TM0 CCRA High Byte Register bit 7~bit 0
TM0 16-bit CCRA bit 15~bit 8
• TM0RP Register – 16-bit STM
Bit
7
6
5
4
3
Name
D7
D6
D5
D4
D3
D2
D1
D0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
0
0
0
0
0
0
0
Bit 7~0TM0RP: TM0 CCRP Register bit 7~bit 0
TM0 CCRP 8-bit register, compared with the TM0 Counter bit 15~bit 8. Comparator P
Match Period
0: 65536 TM0 clocks
1~255: 256×(1~255) TM0 clocks
These eight bits are used to setup the value on the internal CCRP 8-bit register, which
are then compared with the internal counter’s highest eight bits. The result of this
comparison can be selected to clear the internal counter if the T0CCLR bit is set to
zero. Setting the T0CCLR bit to zero ensures that a compare match with the CCRP
values will reset the internal counter. As the CCRP bits are only compared with the
highest eight counter bits, the compare values exist in 256 clock cycle multiples.
Clearing all eight bits to zero is in effect allowing the counter to overflow at its
maximum value.
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10-bit Standard TM Register List
Bit
Register
Name
7
6
5
4
3
2
1
0
TM1C0
T1PAU
T1CK2
T1CK1
T1CK0
T1ON
T1RP2
T1RP1
T1RP0
TM1C1
T1M1
T1M0
T1IO1
T1IO0
T1OC
T1POL
T1DPX
T1CCLR
TM1DL
D7
D6
D5
D4
D3
D2
D1
D0
TM1DH
—
—
—
—
—
—
D9
D8
TM1AL
D7
D6
D5
D4
D3
D2
D1
D0
TM1AH
—
—
—
—
—
—
D9
D8
• TM1C0 Register
Bit
7
6
5
4
3
2
1
0
Name
T1PAU
T1CK2
T1CK1
T1CK0
T1ON
T1RP2
T1RP1
T1RP0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
0
0
0
0
0
0
0
Bit 7T1PAU: TM1 Counter Pause Control
0: Run
1: Pause
The counter can be paused by setting this bit high. Clearing the bit to zero restores
normal counter operation. When in a Pause condition the TM will remain powered up
and continue to consume power. The counter will retain its residual value when this bit
changes from low to high and resume counting from this value when the bit changes
to a low value again.
Bit 6~4T1CK2~T1CK0: Select TM1 Counter clock
000: fSYS/4
001: fSYS
010: fH/16
011: fH/64
100: fTBC (HT66FB540/550/560), fL (HT66FB542)
101: Undefined
110: TCK1 rising edge clock
111: TCK1 falling edge clock
These three bits are used to select the clock source for the TM. Selecting the Reserved
clock input will effectively disable the internal counter. The external pin clock source
can be chosen to be active on the rising or falling edge. The clock source fSYS is the
system clock, while fH and fTBC (fL) are other internal clocks, the details of which can
be found in the oscillator section.
Bit 3T1ON: TM1 Counter On/Off Control
0: Off
1: On
This bit controls the overall on/off function of the TM. Setting the bit high enables the
counter to run, clearing the bit disables the TM. Clearing this bit to zero will stop the
counter from counting and turn off the TM which will reduce its power consumption.
When the bit changes state from low to high the internal counter value will be reset to
zero, however when the bit changes from high to low, the internal counter will retain
its residual value until the bit returns high again.
If the TM is in the Compare Match Output Mode then the TM output pin will be reset
to its initial condition, as specified by the T1OC bit, when the T1ON bit changes from
low to high.
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Bit 2~0T1RP2~T1RP0: TMn CCRP 3-bit register, compared with the TMn Counter bit 9~bit 7
Comparator P Match Period
000: 1024 TM1 clocks
001: 128 TM1 clocks
010: 256 TM1 clocks
011: 384 TM1 clocks
100: 512 TM1 clocks
101: 640 TM1 clocks
110: 768 TM1 clocks
111: 896 TM1 clocks
These three bits are used to setup the value on the internal CCRP 3-bit register, which
are then compared with the internal counter’s highest three bits. The result of this
comparison can be selected to clear the internal counter if the T1CCLR bit is set to
zero. Setting the T1CCLR bit to zero ensures that a compare match with the CCRP
values will reset the internal counter. As the CCRP bits are only compared with the
highest three counter bits, the compare values exist in 128 clock cycle multiples.
Clearing all three bits to zero is in effect allowing the counter to overflow at its
maximum value.
• TM1C1 Register
Bit
7
6
5
4
3
2
1
0
Name
T1M1
T1M0
T1IO1
T1IO0
T1OC
T1POL
T1DPX
T1CCLR
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
0
0
0
0
0
0
0
Bit 7~6T1M1~T1M0: Select TM1 Operating Mode
00: Compare Match Output Mode
01: Capture Input Mode
10: PWM Mode or Single Pulse Output Mode
11: Timer/Counter Mode
These bits setup the required operating mode for the TM. To ensure reliable operation
the TM should be switched off before any changes are made to the T1M1 and T1M0
bits. In the Timer/Counter Mode, the TM output pin control must be disabled.
Bit 5~4T1IO1~T1IO0: Select TP1_0, TP1_1 output function
Compare Match Output Mode
00: No change
01: Output low
10: Output high
11: Toggle output
PWM Mode/Single Pulse Output Mode
00: PWM Output inactive state
01: PWM Output active state
10: PWM output
11: Single pulse output
Capture Input Mode
00: Input capture at rising edge of TP1_0, TP1_1
01: Input capture at falling edge of TP1_0, TP1_1
10: Input capture at falling/rising edge of TP1_0, TP1_1
11: Input capture disabled
Timer/counter Mode:
Unused
These two bits are used to determine how the TM output pin changes state when a
certain condition is reached. The function that these bits select depends upon in which
mode the TM is running. In the Compare Match Output Mode, the T1IO1 and T1IO0
bits determine how the TM output pin changes state when a compare match occurs
from the Comparator A. The TM output pin can be setup to switch high, switch low or
to toggle its present state when a compare match occurs from the Comparator A. When
Rev. 1.40
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the bits are both zero, then no change will take place on the output. The initial value
of the TM output pin should be setup using the T1OC bit in the TM1C1 register. Note
that the output level requested by the T1IO1 and T1IO0 bits must be different from
the initial value setup using the T1OC bit otherwise no change will occur on the TM
output pin when a compare match occurs. After the TM output pin changes state it can
be reset to its initial level by changing the level of the T1ON bit from low to high.
In the PWM Mode, the T1IO1 and T1IO0 bits determine how the TM output pin
changes state when a certain compare match condition occurs. The PWM output
function is modified by changing these two bits. It is necessary to only change
the values of the T1IO1 and T1IO0 bits only after the TM has been switched off.
Unpredictable PWM outputs will occur if the T1IO1 and T1IO0 bits are changed when
the TM is running.
Bit 3T1OC: TP1_0, TP1_1 Output control bit
Compare Match Output Mode
0: Initial low
1: Initial high
PWM Mode/Single Pulse Output Mode
0: Active low
1: Active high
This is the output control bit for the TM output pin. Its operation depends upon
whether TM is being used in the Compare Match Output Mode or in the PWM
Mode/Single Pulse Output Mode. It has no effect if the TM is in the Timer/Counter
Mode. In the Compare Match Output Mode it determines the logic level of the TM
output pin before a compare match occurs. In the PWM Mode it determines if the
PWM signal is active high or active low.
Bit 2T1POL: TP1_0, TP1_1 Output polarity Control
0: Non-invert
1: Invert
This bit controls the polarity of the TP1_0 or TP1_1 output pin. When the bit is set
high the TM output pin will be inverted and not inverted when the bit is zero. It has no
effect if the TM is in the Timer/Counter Mode.
Bit 1T1DPX: TM1 PWM period/duty Control
0: CCRP - period; CCRA - duty
1: CCRP - duty; CCRA - period
This bit, determines which of the CCRA and CCRP registers are used for period and
duty control of the PWM waveform.
Bit 0T1CCLR: Select TM1 Counter clear condition
0: TM1 Comparator P match
1: TM1 Comparator A match
This bit is used to select the method which clears the counter. Remember that the
Standard TM contains two comparators, Comparator A and Comparator P, either of
which can be selected to clear the internal counter. With the T1CCLR bit set high,
the counter will be cleared when a compare match occurs from the Comparator A.
When the bit is low, the counter will be cleared when a compare match occurs from
the Comparator P or with a counter overflow. A counter overflow clearing method can
only be implemented if the CCRP bits are all cleared to zero. The T1CCLR bit is not
used in the PWM, Single Pulse or Input Capture Mode.
Rev. 1.40
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A/D Flash USB 8-Bit MCU with SPI
• TM1DL Register
Bit
7
6
5
4
3
2
1
0
Name
D7
D6
D5
D4
D3
D2
D1
D0
R/W
R
R
R
R
R
R
R
R
POR
0
0
0
0
0
0
0
0
2
1
0
Bit 7~0TM1DL: TM1 Counter Low Byte Register bit 7~bit 0
TM1 10-bit Counter bit 7~bit 0
• TM1DH Register
Bit
7
6
5
4
3
Name
—
—
—
—
—
—
D9
D8
R/W
—
—
—
—
—
—
R
R
POR
—
—
—
—
—
—
0
0
Bit 7~2
Unimplemented, read as "0"
Bit 1~0TM1DH: TM1 Counter High Byte Register bit 1~bit 0
TM1 10-bit Counter bit 9~bit 8
• TM1AL Register
Bit
7
6
5
4
3
2
1
0
Name
D7
D6
D5
D4
D3
D2
D1
D0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
0
0
0
0
0
0
0
2
1
0
Bit 7~0TM1AL: TM1 CCRA Low Byte Register bit 7~bit 0
TM1 10-bit CCRA bit 7~bit 0
• TM1AH Register
Bit
7
6
5
4
3
Name
—
—
—
—
—
—
D9
D8
R/W
—
—
—
—
—
—
R/W
R/W
POR
—
—
—
—
—
—
0
0
Bit 7~2
Unimplemented, read as "0"
Bit 1~0TM1AH: TM1 CCRA High Byte Register bit 1~bit 0
TM1 10-bit CCRA bit 9~bit 8
Rev. 1.40
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A/D Flash USB 8-Bit MCU with SPI
Standard Type TM Operating Modes
The Standard Type TM can operate in one of five operating modes, Compare Match Output Mode,
PWM Output Mode, Single Pulse Output Mode, Capture Input Mode or Timer/Counter Mode. The
operating mode is selected using the TnM1 and TnM0 bits in the TMnC1 register.
Compare Match Output Mode
To select this mode, bits TnM1 and TnM0 in the TMnC1 register, should be set to 00 respectively.
In this mode once the counter is enabled and running it can be cleared by three methods. These are
a counter overflow, a compare match from Comparator A and a compare match from Comparator P.
When the TnCCLR bit is low, there are two ways in which the counter can be cleared. One is when
a compare match from Comparator P, the other is when the CCRP bits are all zero which allows
the counter to overflow. Here both TnAF and TnPF interrupt request flags for Comparator A and
Comparator P respectively, will both be generated.
If the TnCCLR bit in the TMnC1 register is high then the counter will be cleared when a compare
match occurs from Comparator A. However, here only the TnAF interrupt request flag will be
generated even if the value of the CCRP bits is less than that of the CCRA registers. Therefore when
TnCCLR is high no TnPF interrupt request flag will be generated. In the Compare Match Output
Mode, the CCRA can not be set to "0".
As the name of the mode suggests, after a comparison is made, the TM output pin, will change
state. The TM output pin condition however only changes state when a TnAF interrupt request flag
is generated after a compare match occurs from Comparator A. The TnPF interrupt request flag,
generated from a compare match occurs from Comparator P, will have no effect on the TM output
pin. The way in which the TM output pin changes state are determined by the condition of the
TnIO1 and TnIO0 bits in the TMnC1 register. The TM output pin can be selected using the TnIO1
and TnIO0 bits to go high, to go low or to toggle from its present condition when a compare match
occurs from Comparator A. The initial condition of the TM output pin, which is setup after the
TnON bit changes from low to high, is setup using the TnOC bit. Note that if the TnIO1 and TnIO0
bits are zero then no pin change will take place.
Rev. 1.40
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Counte� Value
Counte� ove�flow
CCRP=0
0x3FF/
0xFFFF
TnCCLR = 0; TnM [1:0] = 00
CCRP > 0
Counte� clea�ed �y CCRP value
CCRP > 0
Counte�
Resta�t
Resu�e
CCRP
Pause
CCRA
�to�
Ti�e
TnON
TnPAU
TnPOL
CCRP Int.
Flag TnPF
CCRA Int.
Flag TnAF
TM O/P Pin
Out�ut �in set to
initial Level Low
if TnOC=0
Out�ut not affected �y TnAF
flag. Re�ains High until �eset
�y TnON �it
Out�ut Toggle with
TnAF flag
He�e TnIO [1:0] = 11
Toggle Out�ut select
Note TnIO [1:0] = 10
Active High Out�ut select
Out�ut Inve�ts
when TnPOL is high
Out�ut Pin
Reset to Initial value
Out�ut cont�olled �y
othe� �in-sha�ed function
Compare Match Output Mode – TnCCLR=0
Note: 1. With TnCCLR=0 a Comparator P match will clear the counter
2. The TM output pin is controlled only by the TnAF flag
3. The output pin is reset to its initial state by a TnON bit rising edge
4. n=0, 1
Rev. 1.40
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A/D Flash USB 8-Bit MCU with SPI
TnCCLR = 1; TnM [1:0] = 00
Counte� Value
CCRA = 0
Counte� ove�flow
CCRA > 0 Counte� clea�ed �y CCRA value
0x3FF/
0xFFFF
CCRA=0
Resu�e
CCRA
Pause
�to�
Counte� Resta�t
CCRP
Ti�e
TnON
TnPAU
TnPOL
No TnAF flag
gene�ated on
CCRA ove�flow
CCRA Int.
Flag TnAF
CCRP Int.
Flag TnPF
TM O/P Pin
Out�ut
does not
change
TnPF not
gene�ated
Out�ut �in set
to initial Level
Low if TnOC=0
Out�ut Toggle
with TnAF flag
He�e TnIO [1:0] = 11
Toggle Out�ut select
Out�ut not affected �y
TnAF flag. Re�ains High
until �eset �y TnON �it
Note TnIO [1:0] = 10
Active High Out�ut select
Out�ut Inve�ts
when TnPOL is high
Out�ut Pin
Reset to Initial value
Out�ut cont�olled �y
othe� �in-sha�ed function
Compare Match Output Mode – TnCCLR=1
Note: 1. With TnCCLR=1 a Comparator A match will clear the counter
2. The TM output pin is controlled only by the TnAF flag
3. The output pin is reset to its initial state by a TnON bit rising edge
4. A TnPF flag is not generated when TnCCLR=1
Rev. 1.40
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A/D Flash USB 8-Bit MCU with SPI
Timer/Counter Mode
To select this mode, bits TnM1 and TnM0 in the TMnC1 register should be set to 11 respectively.
The Timer/Counter Mode operates in an identical way to the Compare Match Output Mode
generating the same interrupt flags. The exception is that in the Timer/Counter Mode the TM output
pin is not used. Therefore the above description and Timing Diagrams for the Compare Match
Output Mode can be used to understand its function. As the TM output pin is not used in this mode,
the pin can be used as a normal I/O pin or other pin-shared function.
PWM Output Mode
To select this mode, bits TnM1 and TnM0 in the TMnC1 register should be set to 10 respectively
and also the TnIO1 and TnIO0 bits should be set to 10 respectively. The PWM function within
the TM is useful for applications which require functions such as motor control, heating control,
illumination control etc. By providing a signal of fixed frequency but of varying duty cycle on the
TM output pin, a square wave AC waveform can be generated with varying equivalent DC RMS
values.
As both the period and duty cycle of the PWM waveform can be controlled, the choice of generated
waveform is extremely flexible. In the PWM mode, the TnCCLR bit has no effect as the PWM
period. Both of the CCRA and CCRP registers are used to generate the PWM waveform, one register
is used to clear the internal counter and thus control the PWM waveform frequency, while the other
one is used to control the duty cycle. Which register is used to control either frequency or duty cycle
is determined using the TnDPX bit in the TMnC1 register. The PWM waveform frequency and duty
cycle can therefore be controlled by the values in the CCRA and CCRP registers.
An interrupt flag, one for each of the CCRA and CCRP, will be generated when a compare match
occurs from either Comparator A or Comparator P. The TnOC bit in the TMnC1 register is used to
select the required polarity of the PWM waveform while the two TnIO1 and TnIO0 bits are used to
enable the PWM output or to force the TM output pin to a fixed high or low level. The TnPOL bit is
used to reverse the polarity of the PWM output waveform.
• 16-bit STM, PWM Mode, Edge-aligned Mode, T0DPX=0
CCRP
1~255
Period
CCRP×256
Duty
000b
65536
CCRA
If fSYS=16MHz, TM clock source select fSYS/4, CCRP=2 and CCRA=128, The STM PWM output
frequency=(fSYS/4)/(2×256)=fSYS/2048=7.8125kHz, duty=128/512=25%.
If the Duty value defined by the CCRA register is equal to or greater than the Period value, then the
PWM output duty is 100%.
• 16-bit STM, PWM Mode, Edge-aligned Mode, T0DPX=1
CCRP
1~255
Period
Duty
000b
CCRA
CCRP x 256
65536
The PWM output period is determined by the CCRA register value together with the TM clock while
the PWM duty cycle is defined by the (CCRP×256) except when CCRP value is equal to 000b.
Rev. 1.40
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HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
• 10-bit STM, PWM Mode, Edge-aligned Mode, T1DPX=0
CCRP
001b
010b
011b
100b
101b
110b
111b
000b
Period
128
256
384
512
640
768
896
1024
Duty
CCRA
If fSYS=16MHz, TM clock source select fSYS/4, CCRP=100b and CCRA=128, The STM PWM output
frequency=(fSYS/4)/512=fSYS/2048=7.8125kHz, duty=128/512=25%.
If the Duty value defined by the CCRA register is equal to or greater than the Period value, then the
PWM output duty is 100%.
• 10-bit STM, PWM Mode, Edge-aligned Mode, T1DPX=1
CCRP
001b
010b
011b
100b
Period
Duty
101b
110b
111b
000b
768
896
1024
CCRA
128
256
384
512
640
The PWM output period is determined by the CCRA register value together with the TM clock
while the PWM duty cycle is defined by the CCRP register value.
Counter Value
TnDPX = 0; TnM [1:0] = 10
Counter cleared
by CCRP
Counter Reset when
TnON returns high
CCRP
Pause Resume
CCRA
Counter Stop if
TnON bit low
Time
TnON
TnPAU
TnPOL
CCRA Int.
Flag TnAF
CCRP Int.
Flag TnPF
TM O/P Pin
(TnOC=1)
TM O/P Pin
(TnOC=0)
PWM Duty Cycle
set by CCRA
PWM Period
set by CCRP
PWM resumes
operation
Output controlled by
Output Inverts
other pin-shared function
when TnPOL = 1
PWM Mode – TnDPX=0
Note: 1. Here TnDPX=0 – Counter cleared by CCRP
2. A counter clear sets the PWM Period
3. The internal PWM function continues running even when TnIO [1:0]=00 or 01
4. The TnCCLR bit has no influence on PWM operation
Rev. 1.40
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HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
Counter Value
TnDPX = 1; TnM [1:0] = 10
Counter cleared
by CCRA
Counter Reset when
TnON returns high
CCRA
Pause Resume
CCRP
Counter Stop if
TnON bit low
Time
TnON
TnPAU
TnPOL
CCRP Int.
Flag TnPF
CCRA Int.
Flag TnAF
TM O/P Pin
(TnOC=1)
TM O/P Pin
(TnOC=0)
PWM Duty Cycle
set by CCRP
PWM Period
set by CCRA
PWM resumes
operation
Output controlled by
Output Inverts
other pin-shared function
when TnPOL = 1
PWM Mode – TnDPX=1
Note: 1. Here TnDPX=1 – Counter cleared by CCRA
2. A counter clear sets the PWM Period
3. The internal PWM function continues even when TnIO [1:0]=00 or 01
4. The TnCCLR bit has no influence on PWM operation
Rev. 1.40
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HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
Single Pulse Mode
To select this mode, bits TnM1 and TnM0 in the TMnC1 register should be set to 10 respectively
and also the TnIO1 and TnIO0 bits should be set to 11 respectively. The Single Pulse Output Mode,
as the name suggests, will generate a single shot pulse on the TM output pin.
The trigger for the pulse output leading edge is a low to high transition of the TnON bit, which can
be implemented using the application program. However in the Single Pulse Mode, the TnON bit
can also be made to automatically change from low to high using the external TCKn pin, which will
in turn initiate the Single Pulse output. When the TnON bit transitions to a high level, the counter
will start running and the pulse leading edge will be generated. The TnON bit should remain high
when the pulse is in its active state. The generated pulse trailing edge will be generated when the
TnON bit is cleared to zero, which can be implemented using the application program or when a
compare match occurs from Comparator A.
However a compare match from Comparator A will also automatically clear the TnON bit and thus
generate the Single Pulse output trailing edge. In this way the CCRA value can be used to control
the pulse width. A compare match from Comparator A will also generate a TM interrupt. The counter
can only be reset back to zero when the TnON bit changes from low to high when the counter
restarts. In the Single Pulse Mode CCRP is not used. The TnCCLR and TnDPX bits are not used in
this Mode.
            Single Pulse Generation
Rev. 1.40
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A/D Flash USB 8-Bit MCU with SPI
Counter Value
TnM [1:0] = 10 ; TnIO [1:0] = 11
Counter stopped
by CCRA
Counter Reset when
TnON returns high
CCRA
Pause
Counter Stops
by software
Resume
CCRP
Time
TnON
Software
Trigger
Auto. set by
TCKn pin
Cleared by
CCRA match
TCKn pin
Software
Trigger
Software
Trigger
Software
Software Trigger
Clear
TCKn pin
Trigger
TnPAU
TnPOL
CCRP Int.
Flag TnPF
No CCRP Interrupts
generated
CCRA Int.
Flag TnAF
TM O/P Pin
(TnOC=1)
TM O/P Pin
(TnOC=0)
Output Inverts
when TnPOL = 1
Pulse Width
set by CCRA
Single Pulse Mode
Note: 1. Counter stopped by CCRA
2. CCRP is not used
3. The pulse is triggered by the TCKn pin or by setting the TnON bit high
4. A TCKn pin active edge will automatically set the TnON bit high
5. In the Single Pulse Mode, TnIO [1:0] must be set to "11" and can not be changed.
Rev. 1.40
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A/D Flash USB 8-Bit MCU with SPI
Capture Input Mode
To select this mode bits TnM1 and TnM0 in the TMnC1 register should be set to 01 respectively.
This mode enables external signals to capture and store the present value of the internal counter
and can therefore be used for applications such as pulse width measurements. The external signal is
supplied on the TPn_0 or TPn_1 pin, whose active edge can be either a rising edge, a falling edge or
both rising and falling edges; the active edge transition type is selected using the TnIO1 and TnIO0
bits in the TMnC1 register. The counter is started when the TnON bit changes from low to high
which is initiated using the application program.
When the required edge transition appears on the TPn_0 or TPn_1 pin the present value in the
counter will be latched into the CCRA registers and a TM interrupt generated. Irrespective of what
events occur on the TPn_0 or TPn_1 pin the counter will continue to free run until the TnON bit
changes from high to low. When a CCRP compare match occurs the counter will reset back to zero;
in this way the CCRP value can be used to control the maximum counter value. When a CCRP
compare match occurs from Comparator P, a TM interrupt will also be generated. Counting the
number of overflow interrupt signals from the CCRP can be a useful method in measuring long
pulse widths. The TnIO1 and TnIO0 bits can select the active trigger edge on the TPn_0 or TPn_1
pin to be a rising edge, falling edge or both edge types. If the TnIO1 and TnIO0 bits are both set
high, then no capture operation will take place irrespective of what happens on the TPn_0 or TPn_1
pin, however it must be noted that the counter will continue to run.
As the TPn_0 or TPn_1 pin is pin shared with other functions, care must be taken if the TM is in the
Input Capture Mode. This is because if the pin is setup as an output, then any transitions on this pin
may cause an input capture operation to be executed. The TnCCLR and TnDPX bits are not used in
this Mode.
Rev. 1.40
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A/D Flash USB 8-Bit MCU with SPI
Counte� Value
TnM [1:0] = 01
Counte� clea�ed �y
CCRP
Counte�
�to�
Counte�
Reset
CCRP
Resu�e
YY
Pause
XX
Ti�e
TnON
TnPAU
Active
edge
Active
edge
Active edge
TMn ca�tu�e
�in TPn_x
CCRA Int. Flag
TnAF
CCRP Int. Flag
TnPF
XX
CCRA Value
TnIO [1:0] Value
00 – Rising edge
YY
01 – Falling edge
XX
10 – Both edges
YY
11 – Disa�le Ca�tu�e
Capture Input Mode
Note: 1. TnM [1:0]=01 and active edge set by the TnIO [1:0] bits
2. A TM Capture input pin active edge transfers the counter value to CCRA
3. TnCCLR bit not used
4. No output function – TnOC and TnPOL bits are not used
5. CCRP determines the counter value and the counter has a maximum count value when CCRP is equal to
zero.
Rev. 1.40
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HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
Analog to Digital Converter
The need to interface to real world analog signals is a common requirement for many electronic
systems. However, to properly process these signals by a microcontroller, they must first be
converted into digital signals by A/D converters. By integrating the A/D conversion electronic
circuitry into the microcontroller, the need for external components is reduced significantly with the
corresponding follow-on benefits of lower costs and reduced component space requirements.
A/D Overview
The devices contains a multi-channel analog to digital converter which can directly interface to
external analog signals, such as that from sensors or other control signals and convert these signals
directly into either a 12-bit digital value.
Part No.
Input Channels
A/D Channel Select Bits
Input Pins
HT66FB540
8
ACS4, ACS2~ACS0
AN0~AN7
HT66FB542
4
ACS4, ACS1~ACS0
AN0~AN3
HT66FB550
HT66FB560
16
ACS4~ACS0
AN0~AN15
The accompanying block diagram shows the overall internal structure of the A/D converter, together
with its associated registers.
A/D Converter Register Description
Overall operation of the A/D converter is controlled using a series of registers. A read only register
pair exists to store the ADC data 12-bit value. The remaining three or four registers are control
registers which setup the operating and control function of the A/D converter.
Register Name
ADRL(ADRFS=0)
Bit
7
6
5
4
3
2
1
0
D3
D2
D1
D0
—
—
—
—
ADRL(ADRFS=1)
D7
D6
D5
D4
D3
D2
D1
D0
ADRH(ADRFS=0)
D11
D10
D9
D8
D7
D6
D5
D4
ADRH(ADRFS=1)
—
—
—
—
D11
D10
D9
D8
ADCR0
START
EOCB
ADOFF
ADRFS
—
ACS2
ACS1
ACS0
ADCR1
ACS4
V125EN
—
VREFS
—
ADCK2
ADCK1
ADCK0
ACER0
ACE7
ACE6
ACE5
ACE4
ACE3
ACE2
ACE1
ACE0
HT66FB540 A/D Converter Register List
Register Name
ADRL(ADRFS=0)
Bit
7
6
5
4
3
2
1
0
D3
D2
D1
D0
–
–
–
–
ADRL(ADRFS=1)
D7
D6
D5
D4
D3
D2
D1
D0
ADRH(ADRFS=0)
D11
D10
D9
D8
D7
D6
D5
D4
ADRH(ADRFS=1)
—
—
—
—
D11
D10
D9
D8
ADCR0
START
EOCB
ADOFF
ADRFS
—
—
ACS1
ACS0
ADCR1
ACS4
V125EN
—
VREFS
—
ADCK2
ADCK1
ADCK0
ACER0
—
—
—
—
ACE3
ACE2
ACE1
ACE0
HT66FB542 A/D Converter Register List
Rev. 1.40
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HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
Register Name
Bit
7
6
5
4
3
2
1
0
ADRL(ADRFS=0)
D3
D2
D1
D0
—
—
—
—
ADRL(ADRFS=1)
D7
D6
D5
D4
D3
D2
D1
D0
ADRH(ADRFS=0)
D11
D10
D9
D8
D7
D6
D5
D4
ADRH(ADRFS=1)
—
—
—
—
D11
D10
D9
D8
ADCR0
START
EOCB
ADOFF
ADRFS
ACS3
ACS2
ACS1
ACS0
ADCR1
ACS4
V125EN
—
VREFS
—
ADCK2
ADCK1
ADCK0
ACER0
ACE7
ACE6
ACE5
ACE4
ACE3
ACE2
ACE1
ACE0
ACER1
ACE15
ACE14
ACE13
ACE12
ACE11
ACE10
ACE9
ACE8
HT66FB550/HT66FB560 A/D Converter Register List
     ƒ „  … †
€
 
 
    ‚ ­  
 
A/D Converter Structure
A/D Converter Data Registers – ADRL, ADRH
As the devices contain an internal 12-bit A/D converter, they require two data registers to store the
converted value.
These are a high byte register, known as ADRH, and a low byte register, known as ADRL. After the
conversion process takes place, these registers can be directly read by the microcontroller to obtain
the digitised conversion value. As only 12 bits of the 16-bit register space is utilised, the format
in which the data is stored is controlled by the ADRFS bit in the ADCR0 register as shown in the
accompanying table. D0~D11 are the A/D conversion result data bits. Any unused bits will be read
as zero.
ADRFS
0
1
ADRH
7
6
D11 D10
0
0
5
4
D9
D8
0
0
ADRL
3
2
1
0
7
6
5
D7
D6
D5
D11 D10
D9
4
3
2
1
0
D4
D3
D2
D1
D0
0
0
0
0
D8
D7
D6
D5
D4
D3
D2
D1
D0
A/D Data Registers
Rev. 1.40
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HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
A/D Converter Control Registers – ADCR0, ADCR1, ACER0, ACER1
To control the function and operation of the A/D converter, five control registers known as ADCR0,
ADCR1, ACER0 and ACER1 are provided. These 8-bit registers define functions such as the
selection of which analog channel is connected to the internal A/D converter, the digitised data
format, the A/D clock source as well as controlling the start function and monitoring the A/D
converter end of conversion status. The ACS3~ACS0 bits in the ADCR0 register and ACS4 bit is
the ADCR1 register define the ADC input channel number. As the devices contain only one actual
analog to digital converter hardware circuit, each of the individual 4 or 8 or 16 analog inputs must
be routed to the converter. It is the function of the ACS4 and ACS3~ACS0 bits to determine which
analog channel input pins or internal 1.25V is actually connected to the internal A/D converter.
The ACER1~ACER0 control registers contain the ACE15~ACE0 bits which determine which pins
on PA7, Port B and Port C are used as analog inputs for the A/D converter input and which pins
are not to be used as the A/D converter input. Setting the corresponding bit high will select the A/D
input function, clearing the bit to zero will select either the I/O or other pin-shared function. When
the pin is selected to be an A/D input, its original function whether it is an I/O or other pin-shared
function will be removed. In addition, any internal pull-high resistors connected to these pins will be
automatically removed if the pin is selected to be an A/D input.
ADCR0 Register
• HT66FB540
Bit
7
6
5
4
3
2
1
0
Name
START
EOCB
ADOFF
ADRFS
—
ACS2
ACS1
ACS0
R/W
R/W
R
R/W
R/W
—
R/W
R/W
R/W
POR
0
1
1
0
—
0
0
0
Bit 7START: Start the A/D conversion
0→1→0: start
0→1: reset the A/D converter and set EOCB to "1"
This bit is used to initiate an A/D conversion process. The bit is normally low but if set
high and then cleared low again, the A/D converter will initiate a conversion process.
When the bit is set high the A/D converter will be reset.
Bit 6EOCB: End of A/D conversion flag
0: A/D conversion ended
1: A/D conversion in progress
This read only flag is used to indicate when an A/D conversion process has completed.
When the conversion process is running, the bit will be high.
Bit 5ADOFF : ADC module power on/off control bit
0: ADC module power on
1: ADC module power off
This bit controls the power to the A/D internal function. This bit should be cleared
to zero to enable the A/D converter. If the bit is set high then the A/D converter will
be switched off reducing the devices power consumption. As the A/D converter will
consume a limited amount of power, even when not executing a conversion, this may
be an important consideration in power sensitive battery powered applications.
Note: 1. it is recommended to set ADOFF=1 before entering IDLE/SLEEP Mode for
saving power.
2. ADOFF=1 will power down the ADC module.
Bit 4ADRFS: ADC Data Format Control
0: ADC Data MSB is ADRH bit 7, LSB is ADRL bit 4
1: ADC Data MSB is ADRH bit 3, LSB is ADRL bit 0
This bit controls the format of the 12-bit converted A/D value in the two A/D data
registers. Details are provided in the A/D data register section.
Rev. 1.40
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A/D Flash USB 8-Bit MCU with SPI
Bit 3
Unimplemented, read as "0"
Bit 2~0ACS2, ACS1, ACS0: Select A/D channel (when ACS4 is "0")
000: AN0
001: AN1
010: AN2
011: AN3
100: AN4
101: AN5
110: AN6
111: AN7
These are the A/D channel select control bits. As there is only one internal hardware
A/D converter each of the eight A/D inputs must be routed to the internal converter
using these bits. If bit ACS4 in the ADCR1 register is set high then the internal 1.25V
will be routed to the A/D Converter.
• HT66FB542
Bit
7
6
5
4
3
2
1
0
Name
START
EOCB
ADOFF
ADRFS
—
—
ACS1
ACS0
R/W
R/W
R
R/W
R/W
—
—
R/W
R/W
POR
0
1
1
0
—
—
0
0
Bit 7START: Start the A/D conversion
0→1→0: start
0→1: reset the A/D converter and set EOCB to "1"
This bit is used to initiate an A/D conversion process. The bit is normally low but if set
high and then cleared low again, the A/D converter will initiate a conversion process.
When the bit is set high the A/D converter will be reset.
Bit 6EOCB: End of A/D conversion flag
0: A/D conversion ended
1: A/D conversion in progress
This read only flag is used to indicate when an A/D conversion process has completed.
When the conversion process is running, the bit will be high.
Bit 5ADOFF: ADC module power on/off control bit
0: ADC module power on
1: ADC module power off
This bit controls the power to the A/D internal function. This bit should be cleared
to zero to enable the A/D converter. If the bit is set high then the A/D converter will
be switched off reducing the device power consumption. As the A/D converter will
consume a limited amount of power, even when not executing a conversion, this may
be an important consideration in power sensitive battery powered applications.
Note: 1. it is recommended to set ADOFF=1 before entering IDLE/SLEEP Mode for
saving power.
2. ADOFF=1 will power down the ADC module.
Bit 4ADRFS: ADC Data Format Control
0: ADC Data MSB is ADRH bit 7, LSB is ADRL bit 4
1: ADC Data MSB is ADRH bit 3, LSB is ADRL bit 0
This bit controls the format of the 12-bit converted A/D value in the two A/D data
registers. Details are provided in the A/D data register section.
Bit 3~2
Rev. 1.40
Unimplemented, read as "0"
156
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
Bit 1~0ACS1~ACS0: Select A/D channel (when ACS4 is "0")
00: AN0
01: AN1
10: AN2
11: AN3
These are the A/D channel select control bits. As there is only one internal hardware
A/D converter each of the four A/D inputs must be routed to the internal converter
using these bits. If bit ACS4 in the ADCR1 register is set high then the internal 1.25V
will be routed to the A/D Converter.
• HT66FB550/HT66FB560
Bit
7
6
5
4
3
2
1
0
Name
START
EOCB
ADOFF
ADRFS
ACS3
ACS2
ACS1
ACS0
R/W
R/W
R
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
1
1
0
0
0
0
0
Bit 7START: Start the A/D conversion
0→1→0: start
0→1: reset the A/D converter and set EOCB to "1"
This bit is used to initiate an A/D conversion process. The bit is normally low but if set
high and then cleared low again, the A/D converter will initiate a conversion process.
When the bit is set high the A/D converter will be reset.
Bit 6EOCB: End of A/D conversion flag
0: A/D conversion ended
1: A/D conversion in progress
This read only flag is used to indicate when an A/D conversion process has completed.
When the conversion process is running, the bit will be high.
Bit 5ADOFF : ADC module power on/off control bit
0: ADC module power on
1: ADC module power off
This bit controls the power to the A/D internal function. This bit should be cleared
to zero to enable the A/D converter. If the bit is set high then the A/D converter will
be switched off reducing the devices power consumption. As the A/D converter will
consume a limited amount of power, even when not executing a conversion, this may
be an important consideration in power sensitive battery powered applications.
Note: 1. it is recommended to set ADOFF=1 before entering IDLE/SLEEP Mode for
saving power.
2. ADOFF=1 will power down the ADC module.
Bit 4ADRFS: ADC Data Format Control
0: ADC Data MSB is ADRH bit 7, LSB is ADRL bit 4
1: ADC Data MSB is ADRH bit 3, LSB is ADRL bit 0
This bit controls the format of the 12-bit converted A/D value in the two A/D data
registers. Details are provided in the A/D data register section.
Rev. 1.40
157
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
Bit 3~0
ACS3, ACS2, ACS1, ACS0: Select A/D channel (when ACS4 is "0")
0000: AN0
0001: AN1
0010: AN2
0011: AN3
0100: AN4
0101: AN5
0110: AN6
0111: AN7
1000: AN8
1001: AN9
1010: AN10
1011: AN11
1100: AN12
1101: AN13
1110: AN14
1111: AN15
These are the A/D channel select control bits. As there is only one internal hardware
A/D converter each of the sixteen A/D inputs must be routed to the internal converter
using these bits. If bit ACS4 in the ADCR1 register is set high then the internal 1.25V
will be routed to the A/D Converter.
ADCR1 Register
Bit
7
6
5
4
3
2
1
0
Name
ACS4
V125EN
—
VREFS
—
ADCK2
ADCK1
ADCK0
R/W
R/W
R/W
—
R/W
—
R/W
R/W
R/W
POR
0
0
—
0
—
0
0
0
Bit 7ACS4: Select Internal 1.25V bandgap voltage as ADC input
0: Disable
1: Enable
This bit enables the1.25V bandgap voltage to be connected to the A/D converter. The
V125EN bit must first have been set to enable the bandgap circuit 1.25V voltage to be
used by the A/D converter. When the ACS4 bit is set high, the bandgap 1.25V voltage
will be routed to the A/D converter and the other A/D input channels disconnected.
Bit 6V125EN: Internal 1.25V Control
0: Disable
1: Enable
This bit controls the internal Bandgap circuit on/off function to the A/D converter.
When the bit is set high the 1.25V bandgap voltage can be used as an A/D converter
input. If the 1.25V bandgap voltage is not used by the A/D converter and the
LVR/LVD function is disabled then the bandgap reference circuit will be automatically
switched off to conserve power. When the 1.25V bandgap voltage is switched on
for use by the A/D converter, a time tBG should be allowed for the bandgap circuit to
stabilise before implementing an A/D conversion.
Bit 5
Unimplemented, read as "0"
Bit 4VREFS: Select ADC reference voltage
0: Internal ADC power
1: VREF pin
This bit is used to select the reference voltage for the A/D converter. If the bit is high,
then the A/D converter reference voltage is supplied on the external VREF pin. If the
pin is low, then the internal reference is used which is taken from the power supply
pin, VDD.
Bit 3
Rev. 1.40
Unimplemented, read as "0"
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A/D Flash USB 8-Bit MCU with SPI
Bit 2~0ADCK2, ADCK1, ADCK0: Select ADC clock source
000: fSYS
001: fSYS/2
010: fSYS/4
011: fSYS/8
100: fSYS/16
101: fSYS/32
110: fSYS/64
111: Undefined
These three bits are used to select the clock source for the A/D converter.
ACER0 Register
• HT66FB542
Bit
7
6
5
4
3
2
1
0
Name
—
—
—
—
ACE3
ACE2
ACE1
ACE0
R/W
—
—
—
—
R/W
R/W
R/W
R/W
POR
—
—
—
—
1
1
1
1
Bit 7~4
Unimplemented, read as "0"
Bit 3ACE3: Define PA7 is A/D input or not
0: Not A/D input
1: A/D input, AN3
Bit 2ACE2: Define PB2 is A/D input or not
0: Not A/D input
1: A/D input, AN2
Bit 1ACE1: Define PB1 is A/D input or not
0: Not A/D input
1: A/D input, AN1
Bit 0ACE0: Define PB0 is A/D input or not
0: Not A/D input
1: A/D input, AN0
• HT66FB540/HT66FB550/HT66FB560
Bit
7
6
5
4
3
2
1
0
Name
ACE7
ACE6
ACE5
ACE4
ACE3
ACE2
ACE1
ACE0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
1
1
1
1
1
1
1
1
Bit 7ACE7: Define PA7 is A/D input or not
0: Not A/D input
1: A/D input, AN7
Bit 6ACE6: Define PB6 is A/D input or not
0: Not A/D input
1: A/D input, AN6
Bit 5ACE5: Define PB5 is A/D input or not
0: Not A/D input
1: A/D input, AN5
Bit 4ACE4: Define PB4 is A/D input or not
0: Not A/D input
1: A/D input, AN4
Bit 3ACE3: Define PB3 is A/D input or not
0: Not A/D input
1: A/D input, AN3
Rev. 1.40
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A/D Flash USB 8-Bit MCU with SPI
Bit 2ACE2: Define PB2 is A/D input or not
0: Not A/D input
1: A/D input, AN2
Bit 1ACE1: Define PB1 is A/D input or not
0: Not A/D input
1: A/D input, AN1
Bit 0ACE0: Define PB0 is A/D input or not
0: Not A/D input
1: A/D input, AN0
ACER1 Register
• HT66FB550/HT66FB560
Bit
7
6
5
4
3
2
1
0
Name
ACE15
ACE14
ACE13
ACE12
ACE11
ACE10
ACE9
ACE8
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
1
1
1
1
1
1
1
1
Bit 7ACE15: Define PC7 is A/D input or not
0: Not A/D input
1: A/D input, AN15
Bit 6ACE14: Define PC6 is A/D input or not
0: Not A/D input
1: A/D input, AN14
Bit 5ACE13: Define PC5 is A/D input or not
0: Not A/D input
1: A/D input, AN13
Bit 4ACE12: Define PC4 is A/D input or not
0: Not A/D input
1: A/D input, AN12
Bit 3ACE11: Define PC3 is A/D input or not
0: Not A/D input
1: A/D input, AN11
Bit 2ACE10: Define PC2 is A/D input or not
0: Not A/D input
1: A/D input, AN10
Bit 1ACE9: Define PC1 is A/D input or not
0: Not A/D input
1: A/D input, AN9
Bit 0ACE8: Define PC0 is A/D input or not
0: Not A/D input
1: A/D input, AN8
Rev. 1.40
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A/D Operation
The START bit in the ADCR0 register is used to start and reset the A/D converter. When the
microcontroller sets this bit from low to high and then low again, an analog to digital conversion
cycle will be initiated. When the START bit is brought from low to high but not low again, the
EOCB bit in the ADCR0 register will be set high and the analog to digital converter will be reset.
It is the START bit that is used to control the overall start operation of the internal analog to digital
converter.
The EOCB bit in the ADCR0 register is used to indicate when the analog to digital conversion
process is complete. This bit will be automatically set to "0" by the microcontroller after a
conversion cycle has ended. In addition, the corresponding A/D interrupt request flag will be set
in the interrupt control register, and if the interrupts are enabled, an appropriate internal interrupt
signal will be generated. This A/D internal interrupt signal will direct the program flow to the
associated A/D internal interrupt address for processing. If the A/D internal interrupt is disabled,
the microcontroller can be used to poll the EOCB bit in the ADCR0 register to check whether it has
been cleared as an alternative method of detecting the end of an A/D conversion cycle.
The clock source for the A/D converter, which originates from the system clock fSYS, can be chosen
to be either fSYS or a subdivided version of fSYS. The division ratio value is determined by the
ADCK2~ADCK0 bits in the ADCR1 register.
Although the A/D clock source is determined by the system clock, f SYS , and by bits
ADCK2~ADCK0, there are some limitations on the maximum A/D clock source speed that can
be selected. As the minimum value of permissible A/D clock period, tAD, is 0.5μs, care must be
taken for system clock frequencies equal to or greater than 4MHz. For example, if the system clock
operates at a frequency of 4MHz, the ADCK2~ADCK0 bits should not be set to "000". Doing so
will give A/D clock periods that are less than the minimum A/D clock period which may result in
inaccurate A/D conversion values. Refer to the following table for examples, where values marked
with an asterisk * show where, depending upon the devices, special care must be taken, as the values
may be less than the specified minimum A/D Clock Period.
A/D Clock Period (tAD)
fSYS
ADCK2,
ADCK1,
ADCK0
=000
(fSYS)
ADCK2,
ADCK1,
ADCK0
=001
(fSYS/2)
ADCK2,
ADCK1,
ADCK0
=010
(fSYS/4)
ADCK2,
ADCK1,
ADCK0
=011
(fSYS/8)
ADCK2,
ADCK1,
ADCK0
=100
(fSYS/16)
ADCK2,
ADCK1,
ADCK0
=101
(fSYS/32)
ADCK2,
ADCK1,
ADCK0
=110
(fSYS/64)
ADCK2,
ADCK1,
ADCK0
=111
1MHz
1μs
2μs
4μs
8μs
16μs
32μs
64μs
Undefined
2MHz
500ns
1μs
2μs
4μs
8μs
16μs
32μs
Undefined
4MHz
250ns*
500ns
1μs
2μs
4μs
8μs
16μs
Undefined
8MHz
125ns*
250ns*
500ns
1μs
2μs
4μs
8μs
Undefined
12MHz
83ns*
167ns*
333ns*
667ns
1.33μs
2.67μs
5.33μs
Undefined
16MHz
62ns*
125ns*
250ns*
500ns
1μs
2μs
4μs
Undefined
A/D Clock Period Examples
Controlling the power on/off function of the A/D converter circuitry is implemented using the
ADOFF bit in the ADCR0 register. This bit must be zero to power on the A/D converter. Even if no
pins are selected for use as A/D inputs by clearing the ACE15~ACE0 bits in the ACER1~ACER0
registers, if the ADOFF bit is zero then some power will still be consumed. In power conscious
applications it is therefore recommended that the ADOFF is set high to reduce power consumption
when the A/D converter function is not being used.
The reference voltage supply to the A/D Converter can be supplied from either the positive power supply
pin, VDD, or from an external reference sources supplied on pin VREF. The desired selection is made
using the VREFS bit. As the VREF pin is pin-shared with other functions, when the VREFS bit is set
high, the VREF pin function will be selected and the other pin functions will be disabled automatically.
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A/D Flash USB 8-Bit MCU with SPI
A/D Input Pins
All of the A/D analog input pins are pin-shared with the I/O pins on PA7, Port B and Port C as well
as other functions. The ACE15~ACE0 bits in the ACER1~ACER0 registers, determine whether
the input pins are setup as A/D converter analog inputs or whether they have other functions. If the
ACE15~ACE0 bits for its corresponding pin is set high then the pin will be setup to be an A/D converter
input and the original pin functions disabled. In this way, pins can be changed under program control
to change their function between A/D inputs and other functions. All pull-high resistors, which are
setup through register programming, will be automatically disconnected if the pins are setup as A/D
inputs. Note that it is not necessary to first setup the A/D pin as an input in the PAC, PBC, PCC port
control registers to enable the A/D input as when the ACE15~ACE0 bits enable an A/D input, the
status of the port control register will be overridden.
The A/D converter has its own reference voltage pin, VREF, however the reference voltage can
also be supplied from the power supply pin, a choice which is made through the VREFS bit in the
ADCR1 register. The analog input values must not be allowed to exceed the value of VREF.
Summary of A/D Conversion Steps
The following summarises the individual steps that should be executed in order to implement an
A/D conversion process.
• Step 1
Select the required A/D conversion clock by correctly programming bits ADCK2~ADCK0 in the
ADCR1 register.
• Step 2
Enable the A/D by clearing the ADOFF bit in the ADCR0 register to zero.
• Step 3
Select which channel is to be connected to the internal A/D converter by correctly programming
the ACS4~ACS0 bits which are also contained in the ADCR1 and ADCR0 register.
• Step 4
Select which pins are to be used as A/D inputs and configure them by correctly programming the
ACE15~ACE0 bits in the ACER1~ACER0 registers.
• Step 5
If the interrupts are to be used, the interrupt control registers must be correctly configured to
ensure the A/D converter interrupt function is active. The master interrupt control bit, EMI, and
the A/D converter interrupt bit, ADE, must both be set high to do this.
• Step 6
The analog to digital conversion process can now be initialised by setting the START bit in
the ADCR0 register from low to high and then low again. Note that this bit should have been
originally cleared to zero.
• Step 7
To check when the analog to digital conversion process is complete, the EOCB bit in the ADCR0
register can be polled. The conversion process is complete when this bit goes low. When this
occurs the A/D data registers ADRL and ADRH can be read to obtain the conversion value. As an
alternative method, if the interrupts are enabled and the stack is not full, the program can wait for
an A/D interrupt to occur.
Note: When checking for the end of the conversion process, if the method of polling the EOCB
bit in the ADCR0 register is used, the interrupt enable step above can be omitted.
Rev. 1.40
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A/D Flash USB 8-Bit MCU with SPI
The accompanying diagram shows graphically the various stages involved in an analog to digital
conversion process and its associated timing. After an A/D conversion process has been initiated
by the application program, the microcontroller internal hardware will begin to carry out the
conversion, during which time the program can continue with other functions. The time taken for the
A/D conversion is 16tAD where tAD is equal to the A/D clock period.
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 A/D Conversion Timing
Programming Considerations
During microcontroller operations where the A/D converter is not being used, the A/D internal
circuitry can be switched off to reduce power consumption, by setting bit ADOFF high in the
ADCR0 register. When this happens, the internal A/D converter circuits will not consume power
irrespective of what analog voltage is applied to their input lines. If the A/D converter input lines are
used as normal I/Os, then care must be taken as if the input voltage is not at a valid logic level, then
this may lead to some increase in power consumption.
A/D Transfer Function
As the devices contain a 12-bit A/D converter, its full-scale converted digitised value is equal to
FFFH. Since the full-scale analog input value is equal to the VDD or VREF voltage, this gives a single
bit analog input value of VDD or VREF divided by 4096.
1 LSB=(VDD or VREF)÷4096
The A/D Converter input voltage value can be calculated using the following equation:
A/D input voltage=A/D output digital value × (VDD or VREF)÷4096
The diagram shows the ideal transfer function between the analog input value and the digitised
output value for the A/D converter. Except for the digitised zero value, the subsequent digitised
values will change at a point 0.5 LSB below where they would change without the offset, and the
last full scale digitised value will change at a point 1.5 LSB below the VDD or VREF level.
Rev. 1.40
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A/D Flash USB 8-Bit MCU with SPI
1.� L�B
FFFH
FFEH
FFDH
A/D Conve�sion
Result
03H
0.� L�B
0�H
01H
0
1
�
3
4093 4094 409� 4096
VDD o� VREF
4096
Analog In�ut Voltage
Ideal A/D Transfer Function
A/D Programming Example
The following two programming examples illustrate how to setup and implement an A/D conversion.
In the first example, the method of polling the EOCB bit in the ADCR0 register is used to detect
when the conversion cycle is complete, whereas in the second example, the A/D interrupt is used to
determine when the conversion is complete.
Example: using an EOCB polling method to detect the end of conversion
clr
ADE;
mova,03H
mov ADCR1,a ;
clrADOFF
clr ACER1
mov a,0Fh ;
mov ACER0,a
mova,00h
mov ADCR0,a ;
:
start_conversion:
clr START ;
set START ;
clr START ;
polling_EOC:
sz EOCB ;
;
jmp polling_EOC ;
mov a,ADRL ;
mov ADRL_buffer,a ;
mov a,ADRH ;
mov ADRH_buffer,a ;
:
:
jmp start_conversion ;
Rev. 1.40
disable ADC interrupt
select fSYS/8 as A/D clock and switch off 1.25V
setup ACER to configure pins AN0~AN3
enable and connect AN0 channel to A/D converter
high pulse on start bit to initiate conversion
reset A/D
start A/D
poll the ADCR0 register EOCB bit to detect end
of A/D conversion
continue polling
read low byte conversion result value
save result to user defined register
read high byte conversion result value
save result to user defined register
start next A/D conversion
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Example: using the interrupt method to detect the end of conversion
clr
ADE;
mova,03H
mov ADCR1,a ;
ClrADOFF
clr ACER1
mov a,0Fh ;
mov ACER0,a
mova,00h
mov ADCR0,a ;
Start_conversion:
clr START ;
set START ;
clr START ;
clr ADF ;
set ADE;
set EMI ;
:
:
;
ADC_ISR:
mov acc_stack,a ;
mov a,STATUS
mov status_stack,a ;
:
:
mov a,ADRL ;
mov adrl_buffer,a ;
mov a,ADRH ;
mov adrh_buffer,a ;
:
:
EXIT_INT_ISR:
mov a,status_stack
mov STATUS,a ;
mov a,acc_stack ;
reti
Rev. 1.40
disable ADC interrupt
select fSYS/8 as A/D clock and switch off 1.25V
setup ACER to configure pins AN0~AN3
enable and connect AN0 channel to A/D converter
high pulse on START bit to initiate conversion
reset A/D
start A/D
clear ADC interrupt request flag
enable ADC interrupt
enable global interrupt
ADC interrupt service routine
save ACC to user defined memory
save STATUS to user defined memory
read
save
read
save
low byte conversion result value
result to user defined register
high byte conversion result value
result to user defined register
restore STATUS from user defined memory
restore ACC from user defined memory
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Comparators
The HT66FB540/HT66FB550/HT66FB560 device contains two independent analog comparators, while
the HT66FB542 device contains only one analog comparator. These functions offer flexibility via their
register controlled features such as power-down, polarity select, hysteresis etc. In sharing their pins with
normal I/O pins the comparators do not waste precious I/O pins if there functions are otherwise unused.
Comparator (n=0 or 1)
Comparator Operation
The devices contain one or two comparator functions which are used to compare two analog voltages
and provide an output based on their difference. Full control over the two internal comparators
is provided via two control registers, CP0C and CP1C, one assigned to each comparator. The
comparator output is recorded via a bit in their respective control register, but can also be transferred
out onto a shared I/O pin. Additional comparator functions include, output polarity, hysteresis
functions and power down control.
Any pull-high resistors connected to the shared comparator input pins will be automatically
disconnected when the comparator is enabled. As the comparator inputs approach their switching
level, some spurious output signals may be generated on the comparator output due to the slow
rising or falling nature of the input signals. This can be minimised by selecting the hysteresis
function will apply a small amount of positive feedback to the comparator. Ideally the comparator
should switch at the point where the positive and negative inputs signals are at the same voltage
level, however, unavoidable input offsets introduce some uncertainties here. The hysteresis function,
if enabled, also increases the switching offset value.
Comparator Registers
There are two registers for overall comparator operation, one for each comparator. As corresponding
bits in the two registers have identical functions, they following register table applies to both registers.
Register
Name
Device
Bit
7
6
5
CP0C
HT66FB540/
HT66FB542/
HT66FB550/
HT66FB560
C0SEL
C0EN
CP1C
HT66FB540/
HT66FB550/
HT66FB560
C1SEL
C1EN
4
3
2
1
0
C0POL C0OUT
C0OS
—
—
C0HYEN
C1POL C1OUT
C1OS
—
—
C1HYEN
Comparator Registers List
Comparator Interrupt
Each also possesses its own interrupt function. When any one of the output bits changes state, its
relevant interrupt flag will be set, and if the corresponding interrupt enable bit is set, then a jump
to its relevant interrupt vector will be executed. Note that it is the changing state of the C0OUT or
C1OUT bit and not the output pin which generates an interrupt. If the microcontroller is in the SLEEP
or IDLE Mode and the Comparator is enabled, then if the external input lines cause the Comparator
output to change state, the resulting generated interrupt flag will also generate a wake-up. If it is
required to disable a wake-up from occurring, then the interrupt flag should be first set high before
entering the SLEEP or IDLE Mode.
Rev. 1.40
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Programming Considerations
If the comparator is enabled, it will remain active when the microcontroller enters the SLEEP or
IDLE Mode, however as it will consume a certain amount of power, the user may wish to consider
disabling it before the SLEEP or IDLE Mode is entered.
As comparator pins are shared with normal I/O pins the I/O registers for these pins will be read as
zero (port control register is "1") or read as port data register value (port control register is "0") if the
comparator function is enabled.
CP0C Register
Bit
7
6
5
4
3
2
1
0
Name
C0SEL
C0EN
C0POL
C0OUT
C0OS
—
—
C0HYEN
R/W
R/W
R/W
R/W
R
R/W
—
—
R/W
POR
1
0
0
0
0
—
—
1
C0SEL: Select Comparator pins or I/O pins
0: I/O pin select
1: Comparator pin select
This is the Comparator pin or I/O pin select bit. If the bit is high the comparator will
be selected and the two comparator input pins will be enabled. As a result, these two
pins will lose their I/O pin functions. Any pull-high configuration options associated
with the comparator shared pins will also be automatically disconnected.
Bit 6C0EN: Comparator On/Off control
0: Off
1: On
This is the Comparator on/off control bit. If the bit is zero the comparator will be
switched off and no power consumed even if analog voltages are applied to its inputs.
For power sensitive applications this bit should be cleared to zero if the comparator is
not used or before the devices enter the SLEEP or IDLE mode.
Bit 5C0POL: Comparator output polarity
0: output not inverted
1: output inverted
This is the comparator polarity bit. If the bit is zero then the C0OUT bit will reflect
the non-inverted output condition of the comparator. If the bit is high the comparator
C0OUT bit will be inverted.
Bit 4C0OUT: Comparator output bit
C0POL=0
0: C0+ < C01: C0+ > C0C0POL=1
0: C0+ > C01: C0+ < C0This bit stores the comparator output bit. The polarity of the bit is determined by the
voltages on the comparator inputs and by the condition of the C0POL bit.
Bit 3C0OS: Output path select
0: C0X pin
1: Internal use
This is the comparator output path select control bit. If the bit is set to "0" and the
C0SEL bit is "1" the comparator output is connected to an external C0X pin. If the
bit is set to "1" or the C0SEL bit is "0" the comparator output signal is only used
internally by the devices allowing the shared comparator output pin to retain its normal
I/O operation.
Bit 2~1
Unimplemented, read as "0"
Bit 0C0HYEN: Hysteresis Control
0: Off
1: On
This is the hysteresis control bit and if set high will apply a limited amount of
hysteresis to the comparator, as specified in the Comparator Electrical Characteristics
table. The positive feedback induced by hysteresis reduces the effect of spurious
switching near the comparator threshold.
Bit 7
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• CP1C Register – HT66FB540/HT66FB550/HT66FB560
Bit
7
6
5
4
3
2
1
0
Name
C1SEL
C1EN
C1POL
C1OUT
C1OS
—
—
C1HYEN
R/W
R/W
R/W
R/W
R
R/W
—
—
R/W
POR
1
0
0
0
0
—
—
1
Bit 7C1SEL: Select Comparator pins or I/O pins
0: I/O pin select
1: Comparator pin select
This is the Comparator pin or I/O pin select bit. If the bit is high the comparator will
be selected and the two comparator input pins will be enabled. As a result, these two
pins will lose their I/O pin functions. Any pull-high configuration options associated
with the comparator shared pins will also be automatically disconnected.
Bit 6C1EN: Comparator On/Off control
0: Off
1: On
This is the Comparator on/off control bit. If the bit is zero the comparator will be
switched off and no power consumed even if analog voltages are applied to its inputs.
For power sensitive applications this bit should be cleared to zero if the comparator is
not used or before the devices enter the SLEEP or IDLE mode.
Bit 5C1POL: Comparator output polarity
0: output not inverted
1: output inverted
This is the comparator polarity bit. If the bit is zero then the C1OUT bit will reflect
the non-inverted output condition of the comparator. If the bit is high the comparator
C1OUT bit will be inverted.
Bit 4C1OUT: Comparator output bit
C1POL=0
0: C1+ < C11: C1+ > C1C1POL=1
0: C1+ > C11: C1+ < C1This bit stores the comparator output bit. The polarity of the bit is determined by the
voltages on the comparator inputs and by the condition of the C1POL bit.
Bit 3C1OS: Output path select
0: C1X pin
1: Internal use
This is the comparator output path select control bit. If the bit is set to "0" and the
C1SEL bit is "1" the comparator output is connected to an external C1X pin. If the
bit is set to "1" or the C1SEL bit is "0" the comparator output signal is only used
internally by the devices allowing the shared comparator output pin to retain its normal
I/O operation.
Bit 2~1
Unimplemented, read as "0"
Bit 0C1HYEN: Hysteresis Control
0: Off
1: On
This is the hysteresis control bit and if set high will apply a limited amount of
hysteresis to the comparator, as specified in the Comparator Electrical Characteristics
table. The positive feedback induced by hysteresis reduces the effect of spurious
switching near the comparator threshold.
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Serial Interface Module – SIM
The devices contain a Serial Interface Module, which includes both the four line SPI interface and
the two line I2C interface types, to allow an easy method of communication with external peripheral
hardware. Having relatively simple communication protocols, these serial interface types allow
the microcontroller to interface to external SPI or I2C based hardware such as sensors, Flash or
EEPROM memory, etc. The SIM interface pins are pin-shared with other I/O pins therefore the SIM
interface function must first be selected by software control. As both interface types share the same
pins and registers, the choice of whether the SPI or I2C type is used is made using the SIM operating
mode control bits, named SIM2~SIM0, in the SIMC0 register. These pull-high resistors of the SIM
pin-shared I/O are selected using pull-high control registers, and also if the SIM function is enabled.
There is one control register associated with the serial interface control, namely SBSC. This is used
to enable the SIM WCOL bit function, SPIA WCOL bit function and I2C debounce selection.
The devices provide two kinds of SPI function, namely SPI and SPIA, each of them has the
corresponding WCOL control bits to enable the SIM WCOL and SPIA WCOL control bits, namely
SIM_WCOL and SA_WCOL respectively. In addition, the I2CDB1 and I2CDB0 bits are used to
select the I2C debounce time.
SPI Interface
This SPI interface function, which is part of the Serial Interface Module, should not be confused
with the other independent SPI function, known as SPIA, which is described in another section of
this datasheet.
The SPI interface is often used to communicate with external peripheral devices such as sensors,
Flash or EEPROM memory devices etc. Originally developed by Motorola, the four line SPI
interface is a synchronous serial data interface that has a relatively simple communication protocol
simplifying the programming requirements when communicating with external hardware devices.
The communication is full duplex and operates as a slave/master type, where the devices can be
either master or slave. Although the SPI interface specification can control multiple slave devices
from a single master, but these devices provide only one SCS pin. If the master needs to control
multiple slave devices from a single master, the master can use I/O pin to select the slave devices.
SPI Interface Operation
The SPI interface is a full duplex synchronous serial data link. It is a four line interface with pin
names SDI, SDO, SCK and SCS. Pins SDI and SDO are the Serial Data Input and Serial Data
Output lines, SCK is the Serial Clock line and SCS is the Slave Select line. As the SPI interface
pins are pin-shared with other functions and with the I2C function pins, the SPI interface must first
be selected by the correct bits in the SIMC0 and SIMC2 registers. After the SPI option has been
selected, it can also be additionally disabled or enabled using the SIMEN bit in the SIMC0 register.
SPI Master/Slave Connection
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SPI Bolck Diagram
The SPI function in these devices offers the following features:
• Full duplex synchronous data transfer
• Both Master and Slave modes
• LSB first or MSB first data transmission modes
• Transmission complete flag
• Rising or falling active clock edge
• WCOL bit enabled or disable select
The status of the SPI interface pins is determined by a number of factors such as whether the devices
are in the master or slave mode and upon the condition of certain control bits such as CSEN and
SIMEN.
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SPI Registers
There are four internal registers which control the overall operation of the SPI interface. These are
the SIMD data register and three registers SIMC0, SIMC2 and SBSC. Note that the SIMC1 register
is only used by the I2C interface.
Bit
Register
Name
7
6
5
4
3
2
1
0
SIMC0
SIM2
SIM1
SIM0
PCKEN
PCKP1
PCKP0
SIMEN
—
SIMD
D7
D6
D5
D4
D3
D2
D1
D0
SIMC2
—
—
CKPOLB
CKEG
MLS
CSEN
WCOL
TRF
SBSC
SIM_WCOL
—
I2CDB1
I2CDB0
—
—
—
SA_WCOL
SIM Registers List
The SIMD register is used to store the data being transmitted and received. The same register is used
by both the SPI and I2C functions. Before the devices write data to the SPI bus, the actual data to
be transmitted must be placed in the SIMD register. After the data is received from the SPI bus, the
devices can read it from the SIMD register. Any transmission or reception of data from the SPI bus
must be made via the SIMD register.
• SIMD Register
Bit
7
6
5
4
3
2
1
0
Name
D7
D6
D5
D4
D3
D2
D1
D0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
x
x
x
x
x
x
x
x
"x" unknown
There are also three control registers for the SPI interface, SIMC0 and SIMC2 and SBSC. Note that
the SIMC2 register also has the name SIMA which is used by the I2C function. The SIMC1 register
is not used by the SPI function, only by the I2C function. Register SIMC0 is used to control the
enable/disable function and to set the data transmission clock frequency. Although not connected
with the SPI function, the SIMC0 register is also used to control the Peripheral Clock Prescaler.
Register SIMC2 is used for other control functions such as LSB/MSB selection, write collision flag
etc. The SIM_WCOL bit in the SBSC register is used to control the SPI WCOL function.
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• SIMC0 Register
Bit
7
6
5
4
3
2
1
0
Name
SIM2
SIM1
SIM0
PCKEN
PCKP1
PCKP0
SIMEN
—
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
—
POR
1
1
1
0
0
0
0
—
Bit 7~5
SIM2, SIM1, SIM0: SIM Operating Mode Control
000: SPI master mode; SPI clock is fSYS/4
001: SPI master mode; SPI clock is fSYS/16
010: SPI master mode; SPI clock is fSYS/64
011: SPI master mode; SPI clock is fTBC (HT66FB540/550/560), fL (HT66FB542)
100: SPI master mode; SPI clock is TM0 CCRP match frequency/2
101: SPI slave mode
110: I2C slave mode
111: Non SIM function
These bits setup the overall operating mode of the SIM function. As well as selecting
if the I2C or SPI function, they are used to control the SPI Master/Slave selection and
the SPI Master clock frequency. The SPI clock is a function of the system clock but
can also be chosen to be sourced from TM0 and fTBC (fL). If the SPI Slave Mode is
selected then the clock will be supplied by an external Master devices.
Bit 4PCKEN: PCK Output Pin Control
0: Disable
1: Enable
Bit 3~2
PCKP1, PCKP0: Select PCK output pin frequency
00: fSYS
01: fSYS/4
10: fSYS/8
11: TM0 CCRP match frequency/2
Bit 1SIMEN: SIM Control
0: Disable
1: Enable
The bit is the overall on/off control for the SIM interface. When the SIMEN bit is
cleared to zero to disable the SIM interface, the SDI, SDO, SCK and SCS, or SDA and
SCL lines will lose their SPI or I2C function and the SIM operating current will be
reduced to a minimum value. When the bit is high the SIM interface is enabled. If the
SIM is configured to operate as an SPI interface via the SIM2~SIM0 bits, the contents
of the SPI control registers will remain at the previous settings when the SIMEN bit
changes from low to high and should therefore be first initialised by the application
program. If the SIM is configured to operate as an I2C interface via the SIM2~SIM0
bits and the SIMEN bit changes from low to high, the contents of the I2C control bits
such as HTX and TXAK will remain at the previous settings and should therefore be
first initialised by the application program while the relevant I2C flags such as HCF,
HAAS, HBB, SRW and RXAK will be set to their default states.
Bit 0
Rev. 1.40
Unimplemented, read as "0"
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• SIMC2 Register
Bit
7
6
5
4
3
2
1
0
Name
—
—
CKPOLB
CKEG
MLS
CSEN
WCOL
TRF
R/W
—
—
R/W
R/W
R/W
R/W
R/W
R/W
POR
—
—
0
0
0
0
0
0
Bit 7~6
Undefined bit
This bit can be read or written by the application program.
Bit 5CKPOLB: Determines the base condition of the clock line
0: the SCK line will be high when the clock is inactive
1: the SCK line will be low when the clock is inactive
The CKPOLB bit determines the base condition of the clock line, if the bit is high,
then the SCK line will be low when the clock is inactive. When the CKPOLB bit is
low, then the SCK line will be high when the clock is inactive.
Bit 4CKEG: Determines SPI SCK active clock edge type
CKPOLB=0
0: SCK is high base level and data capture at SCK rising edge
1: SCK is high base level and data capture at SCK falling edge
CKPOLB=1
0: SCK is low base level and data capture at SCK falling edge
1: SCK is low base level and data capture at SCK rising edge
The CKEG and CKPOLB bits are used to setup the way that the clock signal outputs
and inputs data on the SPI bus. These two bits must be configured before data transfer
is executed otherwise an erroneous clock edge may be generated. The CKPOLB bit
determines the base condition of the clock line, if the bit is high, then the SCK line
will be low when the clock is inactive. When the CKPOLB bit is low, then the SCK
line will be high when the clock is inactive. The CKEG bit determines active clock
edge type which depends upon the condition of CKPOLB bit.
Bit 3MLS: SPI Data shift order
0: LSB
1: MSB
This is the data shift select bit and is used to select how the data is transferred, either
MSB or LSB first. Setting the bit high will select MSB first and low for LSB first.
Bit 2CSEN: SPI SCS pin Control
0: Disable
1: Enable
The CSEN bit is used as an enable/disable for the SCS pin. If this bit is low, then the
SCS pin will be disabled and placed into I/O pin or the other functions. If the bit is
high the SCS pin will be enabled and used as a select pin.
Bit 1WCOL: SPI Write Collision flag
0: No collision
1: Collision
The WCOL flag is used to detect if a data collision has occurred. If this bit is high it
means that data has been attempted to be written to the SIMD register during a data
transfer operation. This writing operation will be ignored if data is being transferred.
The bit can be cleared by the application program. Note that using the WCOL bit can
be disabled or enabled via the SIM_WCOL bit in the SBSC register.
Bit 0TRF: SPI Transmit/Receive Complete flag
0: Data is being transferred
1: SPI data transmission is completed
The TRF bit is the Transmit/Receive Complete flag and is set "1" automatically when
an SPI data transmission is completed, but must set to "0" by the application program.
It can be used to generate an interrupt.
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• SBSC Register
Bit
7
6
5
4
Name
R/W
POR
3
2
1
0
SIM_WCOL
—
I2CDB1
I2CDB0
—
R/W
—
R/W
R/W
—
—
—
SA_WCOL
—
—
0
—
0
0
—
—
R/W
—
0
Bit 7: SIM_WCOL: SIM WCOL control bit
0: Disable
1: Enable
Bit 6: Unimplemented, read as "0"
Bit 5,4:
I2CDB1, I2CDB0 : I2C debounce selection bits
Related to I2C function, described elsewhere
Bit 3~1:
Unimplemented, read as "0"
Bit 0: SA_WCOL : SPIA WCOL function control
0: Disable
1: Enable
Related to SPIA function, described elsewhere
SPI Communication
After the SPI interface is enabled by setting the SIMEN bit high, then in the Master Mode, when
data is written to the SIMD register, transmission/reception will begin simultaneously. When the
data transfer is complete, the TRF flag will be set automatically, but must be cleared using the
application program. In the Slave Mode, when the clock signal from the master has been received,
any data in the SIMD register will be transmitted and any data on the SDI pin will be shifted into
the SIMD register. The master should output an SCS signal to enable the slave devices before a
clock signal is provided. The slave data to be transferred should be well prepared at the appropriate
moment relative to the SCS signal depending upon the configurations of the CKPOLB bit and CKEG
bit. The accompanying timing diagram shows the relationship between the slave data and SCS signal
for various configurations of the CKPOLB and CKEG bits.
The SPI will continue to function even in the IDLE Mode.
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SPI Slave Mode Timing – CKEG=1
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SPI Bus Enable/Disable
To enable the SPI bus, set CSEN=1 and SCS=0, then wait for data to be written into the SIMD
(TXRX buffer) register. For the Master Mode, after data has been written to the SIMD (TXRX
buffer) register, then transmission or reception will start automatically. When all the data has been
transferred, the TRF bit should be set. For the Slave Mode, when clock pulses are received on SCK,
data in the TXRX buffer will be shifted out or data on SDI will be shifted in.
To disable the SPI bus, the SCK, SDI, SDO and SCS will become I/O pins or the other functions.
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SPI Operation
All communication is carried out using the 4-line interface for either Master or Slave Mode.
The CSEN bit in the SIMC2 register controls the overall function of the SPI interface. Setting this
bit high will enable the SPI interface by allowing the SCS line to be active, which can then be used
to control the SPI interface. If the CSEN bit is low, the SPI interface will be disabled and the SCS
line will be an I/O pin or the other functions and can therefore not be used for control of the SPI
interface. If the CSEN bit and the SIMEN bit in the SIMC0 are set high, this will place the SDI line
in a floating condition and the SDO line high. If in Master Mode the SCK line will be either high
or low depending upon the clock polarity selection bit CKPOLB in the SIMC2 register. If in Slave
Mode the SCK line will be in a floating condition. If the SIMEN bit is low, then the bus will be
disabled and SCS, SDI, SDO and SCK will all become I/O pins or the other functions. In the Master
Mode the Master will always generate the clock signal. The clock and data transmission will be
initiated after data has been written into the SIMD register. In the Slave Mode, the clock signal will
be received from an external master devices for both data transmission and reception. The following
sequences show the order to be followed for data transfer in both Master and Slave Mode:
Master Mode:
• Step 1
Select the SPI Master mode and clock source using the SIM2~SIM0 bits in the SIMC0 control
register
• Step 2
Setup the CSEN bit and setup the MLS bit to choose if the data is MSB or LSB first, this setting
must be the same with the Slave devices.
• Step 3
Setup the SIMEN bit in the SIMC0 control register to enable the SPI interface.
• Step 4
For write operations: write the data to the SIMD register, which will actually place the data into
the TXRX buffer. Then use the SCK and SCS lines to output the data. After this, go to step5.
For read operations: the data transferred in on the SDI line will be stored in the TXRX buffer
until all the data has been received at which point it will be latched into the SIMD register.
• Step 5
Check the WCOL bit if set high then a collision error has occurred so return to step 4. If equal to
zero then go to the following step.
• Step 6
Check the TRF bit or wait for a SPI serial bus interrupt.
• Step 7
Read data from the SIMD register.
• Step 8
Clear TRF.
• Step 9
Go to step 4.
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Slave Mode:
• Step 1
Select the SPI Slave mode using the SIM2~SIM0 bits in the SIMC0 control register
• Step 2
Setup the CSEN bit and setup the MLS bit to choose if the data is MSB or LSB first, this setting
must be the same with the Master devices.
• Step 3
Setup the SIMEN bit in the SIMC0 control register to enable the SPI interface.
• Step 4
For write operations: write the data to the SIMD register, which will actually place the data into
the TXRX buffer. Then wait for the master clock SCK and SCS signal. After this, go to step5.
For read operations: the data transferred in on the SDI line will be stored in the TXRX buffer
until all the data has been received at which point it will be latched into the SIMD register.
• Step 5
Check the WCOL bit if set high then a collision error has occurred so return to step 4. If equal to
zero then go to the following step.
• Step 6
Check the TRF bit or wait for a SPI serial bus interrupt.
• Step 7
Read data from the SIMD register.
• Step 8
Clear TRF.
• Step 9
Go to step 4.
Error Detection
The WCOL bit in the SIMC2 register is provided to indicate errors during data transfer. The bit is
set by the SPI serial Interface but must be cleared by the application program. This bit indicates a
data collision has occurred which happens if a write to the SIMD register takes place during a data
transfer operation and will prevent the write operation from continuing. The overall function of the
WCOL bit can be disabled or enabled by the SIM_WCOL bit in the SBSC register. .
I2C Interface
The I 2C interface is used to communicate with external peripheral devices such as sensors,
EEPROM memory etc. Originally developed by Philips, it is a two line low speed serial interface
for synchronous serial data transfer. The advantage of only two lines for communication, relatively
simple communication protocol and the ability to accommodate multiple devices on the same bus
has made it an extremely popular interface type for many applications.
I2C Master Slave Bus Connection
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I2C Interface Operation
The I2C serial interface is a two line interface, a serial data line, SDA, and serial clock line, SCL. As
many devices may be connected together on the same bus, their outputs are both open drain types.
For this reason it is necessary that external pull-high resistors are connected to these outputs. Note
that no chip select line exists, as each device on the I2C bus is identified by a unique address which
will be transmitted and received on the I2C bus.
When two devices communicate with each other on the bidirectional I2C bus, one is known as the
master device and one as the slave device. Both master and slave can transmit and receive data,
however, it is the master device that has overall control of the bus. For these devices, which only
operate in slave mode, there are two methods of transferring data on the I2C bus, the slave transmit
mode and the slave receive mode.
The debounce time of the I2C interface can be determined by the I2CDB1 and I2CDB0 bits in the
SBSC register. This uses the internal clock to in effect add a debounce time to the external clock to
reduce the possibility of glitches on the clock line causing erroneous operation. The debounce time,
if selected, can be chosen to be either 1 or 2 system clocks.
Data Bus
I�C Data Registe�
(�IMD)
f�Y�
�CL Pin
�DA Pin
HTX
De�ounce
Ci�cuit�y
I�CDB[1:0]
I�C Add�ess Registe�
(�IMA)
Add�ess Add�ess Match–HAA�
Co��a�ato�
Di�ection Cont�ol
Data in M�B
M
U
X
�hift Registe�
�RW
Data out M�B
TXAK
�-�it Data T�ansfe� Co��lete–HCF
T�ans�it/
Receive
Cont�ol Unit
CLK*
I�CTOEN
Read/W�ite �lave
I�C Inte��u�t
Detect �ta�t o� �to�
HBB
I�CTOF
Ti�e-out
Cont�ol
Add�ess Match
Note: CLK = fTBC fo� HT66FB�40/HT66FB��0/HT66FB�60� CLK = fL fo� HT66FB�4�.
I2C Block Diagram
S T A R T s ig n a l
fro m M a s te r
S e n d s la v e a d d r e s s
a n d R /W b it fr o m M a s te r
A c k n o w le d g e
fr o m s la v e
S e n d d a ta b y te
fro m M a s te r
A c k n o w le d g e
fr o m s la v e
S T O P s ig n a l
fro m M a s te r
Rev. 1.40
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A/D Flash USB 8-Bit MCU with SPI
I2C Registers
There are three control registers associated with the I2C bus, SIMC0, SIMC1 and SBSC, one
address register SIMA and one data register, SIMD. The SIMD register, which is shown in the
above SPI section, is used to store the data being transmitted and received on the I2C bus. Before
the microcontroller writes data to the I2C bus, the actual data to be transmitted must be placed in the
SIMD register. After the data is received from the I2C bus, the microcontroller can read it from the
SIMD register. Any transmission or reception of data from the I2C bus must be made via the SIMD
register.
Note that the SIMA register also has the name SIMC2 which is used by the SPI function. Bit SIMEN
and bits SIM2~SIM0 in register SIMC0 are used by the I2C interface. The I2CDB0 and I2CDB1 in
the SBSC register are used to select the I2C debounce time.
Bit
Register
Name
7
6
5
4
3
2
1
0
SIMC0
SIM2
SIM1
SIM0
PCKEN
PCKP1
PCKP0
SIMEN
—
SIMC1
HCF
HAAS
HBB
HTX
TXAK
SRW
IAMWU
RXAK
SIMD
D7
D6
D5
D4
D3
D2
D1
D0
SIMA
IICA6
IICA5
IICA4
IICA3
IICA2
IICA1
IICA0
—
SBSC
SIM_WCOL
—
I2CDB1
I2CDB0
—
—
—
SA_WCOL
I2C Registers List
• SIMC0 Register
Bit
7
6
5
4
3
2
1
Name
SIM2
SIM1
SIM0
PCKEN
PCKP1
PCKP0
SIMEN
—
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
—
POR
1
1
1
0
0
0
0
—
Bit 7~5
0
SIM2, SIM1, SIM0: SIM Operating Mode Control
000: SPI master mode; SPI clock is fSYS/4
001: SPI master mode; SPI clock is fSYS/16
010: SPI master mode; SPI clock is fSYS/64
011: SPI master mode; SPI clock is fTBC (HT66FB540/550/560), fL (HT66FB542)
100: SPI master mode; SPI clock is TM0 CCRP match frequency/2
101: SPI slave mode
110: I2C slave mode
111: Non SIM function
These bits setup the overall operating mode of the SIM function. As well as selecting
if the I2C or SPI function, they are used to control the SPI Master/Slave selection and
the SPI Master clock frequency. The SPI clock is a function of the system clock but
can also be chosen to be sourced from the TM0 and fTBC (fL). If the SPI Slave Mode is
selected then the clock will be supplied by an external Master device.
Bit 4PCKEN: PCK Output Pin Control
0: Disable
1: Enable
Bit 3~2
Rev. 1.40
PCKP1, PCKP0: Select PCK output pin frequency
00: fSYS
01: fSYS/4
10: fSYS/8
11: TM0 CCRP match frequency/2
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Bit 1SIMEN: SIM Control
0: Disable
1: Enable
The bit is the overall on/off control for the SIM interface. When the SIMEN bit is
cleared to zero to disable the SIM interface, the SDI, SDO, SCK and SCS, or SDA and
SCL lines will be in a floating condition and the SIM operating current will be reduced
to a minimum value. When the bit is high the SIM interface is enabled. If the SIM is
configured to operate as an SPI interface via SIM2~SIM0 bits, the contents of the SPI
control registers will remain at the previous settings when the SIMEN bit changes
from low to high and should therefore be first initialised by the application program.
If the SIM is configured to operate as an I2C interface via the SIM2~SIM0 bits and the
SIMEN bit changes from low to high, the contents of the I2C control bits such as HTX
and TXAK will remain at the previous settings and should therefore be first initialised
by the application program while the relevant I2C flags such as HCF, HAAS, HBB,
SRW and RXAK will be set to their default states.
Bit 0
Unimplemented, read as "0"
• SIMC1 Register
Bit
7
6
5
4
3
2
1
0
Name
HCF
HAAS
HBB
HTX
TXAK
SRW
IAMWU
RXAK
R/W
R
R
R
R/W
R/W
R
R/W
R
POR
1
0
0
0
0
0
0
1
Bit 7HCF: I C Bus data transfer completion flag
0: Data is being transferred
1: Completion of an 8-bit data transfer
The HCF flag is the data transfer flag. This flag will be zero when data is being
transferred. Upon completion of an 8-bit data transfer the flag will go high and an
interrupt will be generated.
2
Bit 6HAAS: I2C Bus address match flag
0: Not address match
1: Address match
The HAAS flag is the address match flag. This flag is used to determine if the slave
device address is the same as the master transmit address. If the addresses match then
this bit will be high, if there is no match then the flag will be low.
Bit 5HBB: I2C Bus busy flag
0: I2C Bus is not busy
1: I2C Bus is busy
The HBB flag is the I2C busy flag. This flag will be "1" when the I2C bus is busy which
will occur when a START signal is detected. The flag will be set to "0" when the bus is
free which will occur when a STOP signal is detected.
Bit 4HTX: Select I2C slave device is transmitter or receiver
0: Slave device is the receiver
1: Slave device is the transmitter
Bit 3TXAK: I2C Bus transmit acknowledge flag
0: Slave send acknowledge flag
1: Slave do not send acknowledge flag
The TXAK bit is the transmit acknowledge flag. After the slave device receipt of 8 bits
of data, this bit will be transmitted to the bus on the 9th clock from the slave device.
The slave device must always set TXAK bit to "0" before further data is received.
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A/D Flash USB 8-Bit MCU with SPI
Bit 2SRW: I2C Slave Read/Write flag
0: Slave device should be in receive mode
1: Slave device should be in transmit mode
The SRW flag is the I 2C Slave Read/Write flag. This flag determines whether
the master device wishes to transmit or receive data from the I2C bus. When the
transmitted address and slave address is match, that is when the HAAS flag is set high,
the slave device will check the SRW flag to determine whether it should be in transmit
mode or receive mode. If the SRW flag is high, the master is requesting to read data
from the bus, so the slave device should be in transmit mode. When the SRW flag
is zero, the master will write data to the bus, therefore the slave device should be in
receive mode to read this data.
Bit 1IAMWU: I2C Address Match Wake-up Control
0: Disable
1: Enable
This bit should be set to "1" to enable I2C address match wake up from SLEEP or
IDLE Mode.
Bit 0RXAK: I2C Bus Receive acknowledge flag
0: Slave receive acknowledge flag
1: Slave does not receive acknowledge flag
The RXAK flag is the receiver acknowledge flag. When the RXAK flag is "0", it
means that a acknowledge signal has been received at the 9th clock, after 8 bits of data
have been transmitted. When the slave device in the transmit mode, the slave device
checks the RXAK flag to determine if the master receiver wishes to receive the next
byte. The slave transmitter will therefore continue sending out data until the RXAK
flag is "1". When this occurs, the slave transmitter will release the SDA line to allow
the master to send a STOP signal to release the I2C Bus.
The SIMD register is used to store the data being transmitted and received. The same
register is used by both the SPI and I2C functions. Before the devices write data to the
SPI bus, the actual data to be transmitted must be placed in the SIMD register. After
the data is received from the SPI bus, the devices can read it from the SIMD register.
Any transmission or reception of data from the SPI bus must be made via the SIMD
register.
• SIMD Register
Bit
7
6
5
4
3
2
1
0
Name
D7
D6
D5
D4
D3
D2
D1
D0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
x
x
x
x
x
x
x
x
"x" unknown
Rev. 1.40
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A/D Flash USB 8-Bit MCU with SPI
• SIMA Register
Bit
7
6
5
4
3
2
1
0
Name
IICA6
IICA5
IICA4
IICA3
IICA2
IICA1
IICA0
—
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
—
POR
x
x
x
x
x
x
x
—
"x" unknown
Bit 7~1IICA6~IICA0: I2C slave address
IICA6~IICA0 is the I2C slave address bit 6~bit 0.
The SIMA register is also used by the SPI interface but has the name SIMC2. The
SIMA register is the location where the 7-bit slave address of the slave device is stored.
Bits 7~1 of the SIMA register define the device slave address. Bit 0 is not defined.
When a master device, which is connected to the I2C bus, sends out an address, which
matches the slave address in the SIMA register, the slave device will be selected. Note
that the SIMA register is the same register address as SIMC2 which is used by the SPI
interface.
Bit 0
Undefined bit
This bit can be read or written by user software program.
• SBSC Register
Bit
7
6
5
4
3
2
1
0
Name
SIM_WCOL
—
I2CDB1
I2CDB0
—
—
—
SA_WCOL
R/W
R/W
—
R/W
R/W
—
—
—
R/W
POR
0
—
0
0
—
—
—
0
Bit 7SIM_WCOL : SIM WCOL control bit
Related to SPI, described elsewhere.
Bit 6
Unimplemented, read as "0"
Bit 5, 4I2CDB1, I2CDB0: I2C debounce selection bits
00: No debounce (default)
01: 1 system clock debounce
10, 11: 2 system clocks debounce
Bit 3~1
Unimplemented, read as "0"
Bit 0SA_WCOL: SPIA WCOL function control
Related to SPIA, described elsewhere.
Rev. 1.40
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A/D Flash USB 8-Bit MCU with SPI
I2C Bus Communication
Communication on the I2C bus requires four separate steps, a START signal, a slave device address
transmission, a data transmission and finally a STOP signal. When a START signal is placed on
the I2C bus, all devices on the bus will receive this signal and be notified of the imminent arrival of
data on the bus. The first seven bits of the data will be the slave address with the first bit being the
MSB. If the address of the slave device matches that of the transmitted address, the HAAS bit in the
SIMC1 register will be set and an I2C interrupt will be generated. After entering the interrupt service
routine, the slave device must first check the condition of the HAAS and I2CTOF bits to determine
whether the interrupt source originates from an address match or from the completion of an 8-bit
data transfer or I2C bus time-out. During a data transfer, note that after the 7-bit slave address has
been transmitted, the following bit, which is the 8th bit, is the read/write bit whose value will be
placed in the SRW bit. This bit will be checked by the slave device to determine whether to go into
transmit or receive mode. Before any transfer of data to or from the I2C bus, the microcontroller
must initialise the bus, the following are steps to achieve this:
• Step 1
Set the SIM2~SIM0 and SIMEN bits in the SIMC0 register to "110" and "1" respectively to
enable the I2C bus.
• Step 2
Write the slave address of the device to the I2C bus address register SIMA.
• Step 3
Set the SIME interrupt enable bit of the interrupt control register to enable the SIM interrupt.

 ­ €  ‚ ƒ „ …  €        I2C Bus Initialisation Flow Chart
Rev. 1.40
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A/D Flash USB 8-Bit MCU with SPI
I2C Bus Start Signal
The START signal can only be generated by the master device connected to the I2C bus and not by
the slave device. This START signal will be detected by all devices connected to the I2C bus. When
detected, this indicates that the I2C bus is busy and therefore the HBB bit will be set. A START
condition occurs when a high to low transition on the SDA line takes place when the SCL line
remains high.
Slave Address
The transmission of a START signal by the master will be detected by all devices on the I2C bus.
To determine which slave device the master wishes to communicate with, the address of the slave
device will be sent out immediately following the START signal. All slave devices, after receiving
this 7-bit address data, will compare it with their own 7-bit slave address. If the address sent out by
the master matches the internal address of the microcontroller slave device, then an internal I2C bus
interrupt signal will be generated. The next bit following the address, which is the 8th bit, defines
the read/write status and will be saved to the SRW bit of the SIMC1 register. The slave device will
then transmit an acknowledge bit, which is a low level, as the 9th bit. The slave device will also set
the status flag HAAS when the addresses match.
As an I2C bus interrupt can come from three sources, when the program enters the interrupt
subroutine, the HAAS and I2CTOF bits should be examined to see whether the interrupt source has
come from a matching slave address or from the completion of a data byte transfer or I2C bus timeout. When a slave address is matched, the devices must be placed in either the transmit mode and
then write data to the SIMD register, or in the receive mode where it must implement a dummy read
from the SIMD register to release the SCL line.
I2C Bus Read/Write Signal
The SRW bit in the SIMC1 register defines whether the slave device wishes to read data from the
I2C bus or write data to the I2C bus. The slave device should examine this bit to determine if it is to
be a transmitter or a receiver. If the SRW flag is "1" then this indicates that the master device wishes
to read data from the I2C bus, therefore the slave device must be setup to send data to the I2C bus as
a transmitter. If the SRW flag is "0" then this indicates that the master wishes to send data to the I2C
bus, therefore the slave device must be setup to read data from the I2C bus as a receiver.
I2C Bus Slave Address Acknowledge Signal
After the master has transmitted a calling address, any slave device on the I 2C bus, whose
own internal address matches the calling address, must generate an acknowledge signal. The
acknowledge signal will inform the master that a slave device has accepted its calling address. If no
acknowledge signal is received by the master then a STOP signal must be transmitted by the master
to end the communication. When the HAAS flag is high, the addresses have matched and the slave
device must check the SRW flag to determine if it is to be a transmitter or a receiver. If the SRW flag
is high, the slave device should be setup to be a transmitter so the HTX bit in the SIMC1 register
should be set to "1". If the SRW flag is low, then the microcontroller slave device should be setup as
a receiver and the HTX bit in the SIMC1 register should be set to "0".
Rev. 1.40
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A/D Flash USB 8-Bit MCU with SPI
I2C Bus Data and Acknowledge Signal
The transmitted data is 8-bit wide and is transmitted after the slave device has acknowledged receipt
of its slave address. The order of serial bit transmission is the MSB first and the LSB last. After
receipt of 8 bits of data, the receiver must transmit an acknowledge signal, level "0", before it can
receive the next data byte. If the slave transmitter does not receive an acknowledge bit signal from
the master receiver, then the slave transmitter will release the SDA line to allow the master to send
a STOP signal to release the I2C Bus. The corresponding data will be stored in the SIMD register.
If setup as a transmitter, the slave device must first write the data to be transmitted into the SIMD
register. If setup as a receiver, the slave device must read the transmitted data from the SIMD
register.
When the slave receiver receives the data byte, it must generate an acknowledge bit, known as
TXAK, on the 9th clock. The slave device, which is setup as a transmitter will check the RXAK bit
in the SIMC1 register to determine if it is to send another data byte, if not then it will release the
SDA line and await the receipt of a STOP signal from the master.
€
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­
         ­ I2C Communication Timing Diagram
Note: *When a slave address is matched, the devices must be placed in either the transmit mode
and then write data to the SIMD register, or in the receive mode where it must implement a
dummy read from the SIMD register to release the SCL line.
Rev. 1.40
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A/D Flash USB 8-Bit MCU with SPI
�ta�t
No
No
No
HTX=1?
Yes
HAA�=1?
Yes
I�CTOF=1?
Yes
Yes
�ET I�CTOEN
CLR I�CTOF
�RW=1?
No
RETI
Read f�o� �IMD to
�elease �CL Line
RETI
Yes
�ET HTX
CLR HTX
CLR TXAK
W�ite data to �IMD to
�elease �CL Line
Du��y �ead f�o� �IMD
to �elease �CL Line
RETI
RETI
RXAK=1?
No
CLR HTX
CLR TXAK
W�ite data to �IMD to
�elease �CL Line
Du��y �ead f�o� �IMD
to �elease �CL Line
RETI
RETI
I2C Bus ISR flow Chart
I2C Time Out function
The I2C interface provides a time-out scheme to prevent a locked situation which might take
place by an unexpected clock timing generated by a noise input signal. When the I2C interface
has been locked for a period of time, the I2C hardware and the register, SIMC1, will be initialized
automatically and the I2CTOF bit in the I2CTOC register will be set high. The Time Out function
eable/disable and the time-out period are managed by the I2CTOC register.
Rev. 1.40
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HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
�CL
�ta�t
�lave Add�ess
1
�DA
0
1
1
0
1
�RW
ACK
1
0
0
I�C ti�e-out
counte� sta�t
�to�
�CL
1
0
0
1
0
1
0
0
�DA
I�C ti�e-out counte� �eset
on �CL negative t�ansition
I2C Time-out
I2C Time Out operation
The time-out counter will start counting when the I2C interface received the START bit and address
match. After that the counter will be cleared on each falling edge of the SCL pin. If the time counter
is larger than the selected time-out time, then the anti-locked protection scheme will take place and
the time-out counter will be stopped by hardware automatically, the I2CTOF bit will be set high and
an I2C interrupt will also take place. Note that this scheme can also be stopped when the I2C received
the STOP bit. There are several time-out periods can be selected by the I2CTOS0~I2CTOS5 bits in
the I2CTOC register.
• I2CTOC Register
Bit
7
6
Name
I2CTOEN
I2CTOF
5
4
3
2
1
0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
0
0
0
0
0
0
0
I2CTOS5 I2CTOS4 I2CTOS3 I2CTOS2 I2CTOS1 I2CTOS0
Bit 7I2CTOEN: I C Time Out function control bit
0: Disable
1: Enable 2
Bit 6I2CTOF: I2C Time Out indication bit
0: Not occurred
1: Occurred
Bit 5~0I2CTOS5~I2CTOS0: I2C Time out time period select
The I2C Time out clock is provided by the fSUB/32. The time out time period can be
calculated from the accompanying equation ([I2CTOS5: I2CTOS0]+1)×(32/fSUB).
Rev. 1.40
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A/D Flash USB 8-Bit MCU with SPI
Serial Interface – SPIA
The devices contain an independent SPI function. It is important not to confuse this independent SPI
function with the additional one contained within the combined SIM function, which is described
in another section of this datasheet. This independent SPI function will carry the name SPIA to
distinguish it from the other one in the SIM.
The SPIA interface is often used to communicate with external peripheral devices such as sensors,
Flash or EEPROM memory devices etc. Originally developed by Motorola, the four line SPIA
interface is a synchronous serial data interface that has a relatively simple communication protocol
simplifying the programming requirements when communicating with external hardware devices.
The communication is full duplex and operates as a slave/master type, where the device can be
either master or slave. Although the SPIA interface specification can control multiple slave devices
from a single master, however these devices are provided with only one SCSA pin. If the master
needs to control multiple slave devices from a single master, the master can use I/O pins to select the
slave devices.
SPIA Interface Operation
The SPIA interface is a full duplex synchronous serial data link. It is a four line interface with
pin names SDIA, SDOA, SCKA and SCSA. Pins SDIA and SDOA are the Serial Data Input and
Serial Data Output lines, SCKA is the Serial Clock line and SCSA is the Slave Select line. As the
SPIA interface pins are pin-shared with normal I/O pins, the SPIA interface must first be enabled
by setting the correct bits in the SPIAC0 and SPIAC1 registers. The SPIA can be disabled or
enabled using the SPIAEN bit in the SPIAC0 register. Communication between devices connected
to the SPIA interface is carried out in a slave/master mode with all data transfer initiations being
implemented by the master. The Master also controls the clock signal. As the device only contains a
single SCSA pin only one slave device can be utilized.
The SCSA pin is controlled by the application program, set the SACSEN bit to "1" to enable the
SCSA pin function and clear the SACSEN bit to "0" to place the SCSA pin into a floating state.
SPIA Master/Slave Connection
Rev. 1.40
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HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
  
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SPIA Block Diagram
The SPIA function in these devices offers the following features:
• Full duplex synchronous data transfer
• Both Master and Slave modes
• LSB first or MSB first data transmission modes
• Transmission complete flag
• Rising or falling active clock edge
• SAWCOL bit enabled or disable select
The status of the SPIA interface pins is determined by a number of factors such as whether the
device is in the master or slave mode and upon the condition of certain control bits such as SACSEN
and SPIAEN.
SPIA Registers
There are four internal registers which control the overall operation of the SPIA interface. These are
the SPIAD data register and three registers SPIAC0, SPIAC1 and SBSC. The SA_WCOL bit in the
SBSC register is used to control the SPIA WCOL function.
Bit
Register
Name
7
6
5
4
3
2
1
0
SPIAC0
SASPI2
SASPI1
SASPI0
—
—
—
SPIAEN
—
SPIAC1
—
—
SPIAD
D7
D6
SACKPOL SACKEG SAMLS
D5
D4
D3
SACSEN SAWCOL
D2
D1
SATRF
D0
SBSC
SIM_WCOL
—
I2CDB1
I2CDB0
—
—
—
SA_WCOL
SPIA Registers List
The SPIAD register is used to store the data being transmitted and received. Before the device
writes data to the SPIA bus, the actual data to be transmitted must be placed in the SPIAD register.
After the data is received from the SPIA bus, the device can read it from the SPIAD register. Any
transmission or reception of data from the SPIA bus must be made via the SPIAD register.
Rev. 1.40
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A/D Flash USB 8-Bit MCU with SPI
SPIAD Register
Bit
7
6
5
4
3
2
1
0
Name
D7
D6
D5
D4
D3
D2
D1
D0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
x
x
x
x
x
x
x
x
"x" unknown
There are also three control registers for the SPIA interface, SPIAC0, SPIAC1 and SBSC. Register
SPIAC0 is used to control the enable/disable function and to set the data transmission clock
frequency. Register SPIAC1 is used for other control functions such as LSB/MSB selection, write
collision flag etc.
SPIAC0 Register
Bit
7
6
5
4
3
2
1
0
Name
SASPI2
SASPI1
SASPI0
—
—
—
SPIAEN
—
R/W
R/W
R/W
R/W
—
—
—
R/W
—
POR
1
1
1
—
—
—
0
—
Bit 7~5SASPI2~SASPI0: Master/Slave Clock Select
000 : SPIA master, fSYS/4
001 : SPIA master, fSYS/16
010 : SPIA master, fSYS/64
011 : SPIA master, fTBC (HT66FB540/550/560), fL (HT66FB542)
100 : SPIA master, TM0 CCRP match frequency/2
101 : SPIA slave
110: Unimplemented, read as "0"
111: Unimplemented, read as "0"
These bits are used to control the SPI Master/Slave selection and the SPIA Master
clock frequency. The SPIA clock is a function of the system clock but can also be
chosen to be sourced from TM0 and fTBC (fL). If the SPIA Slave Mode is selected then
the clock will be supplied by an external Master device.
Bit 4~2
Unimplemented, read as "0"
Bit 1SPIAEN: SPIA enable or disable
0: Disable
1: Enable
The bit is the overall on/off control for the SPIA interface. When the SPIAEN bit
is cleared to zero to disable the SPIA interface, the SDIA, SDOA, SCKA and SCSA
lines will lose their SPIA function and the SPIA operating current will be reduced to a
minimum value. When the bit is high the SPIA interface is enabled.
Bit 0
Rev. 1.40
Unimplemented, read as "0"
191
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
SPIAC1 Register
Bit
7
6
5
4
SAMLS
2
1
SACSEN SAWCOL
0
Name
—
—
R/W
—
—
R/W
R/W
R/W
R/W
R/W
R/W
POR
—
—
0
0
0
0
0
0
Bit 7~6
SACKPOL SACKEG
3
SATRF
Unimplemented, read as "0".
This bit can be read or written by user software program.
Bit 5SACKPOL: Determines the base condition of the clock line
0: SCKA line will be high when the clock is inactive
1: SCKA line will be low when the clock is inactive
The SACKPOL bit determines the base condition of the clock line, if the bit is high,
then the SCKA line will be low when the clock is inactive. When the SACKPOL bit is
low, then the SCKA line will be high when the clock is inactive.
Bit 4SACKEG: Determines the SPIA SCKA active clock edge type
SACKPOL=0
0: SCKA has high base level with data capture on SCKA rising edge
1: SCKA has high base level with data capture on SCKA falling edge
SACKPOL=1
0: SCKA has low base level with data capture on SCKA falling edge
1: SCKA has low base level with data capture on SCKA rising edge
The SACKEG and SACKPOL bits are used to setup the way that the clock signal
outputs and inputs data on the SPIA bus. These two bits must be configured before a
data transfer is executed otherwise an erroneous clock edge may be generated. The
SACKPOL bit determines the base condition of the clock line, if the bit is high, then the
SCKA line will be low when the clock is inactive. When the SACKPOL bit is low, then
the SCKA line will be high when the clock is inactive. The SACKEG bit determines
active clock edge type which depends upon the condition of the SACKPOL bit.
Bit 3SAMLS: MSB/LSB First Bit
0: LSB shift first
1: MSB shift first
This is the data shift select bit and is used to select how the data is transferred, either
MSB or LSB first. Setting the bit high will select MSB first and low for LSB first.
Bit 2SACSEN: Select Signal Enable/Disable Bit
0: Disable, other functions
1: Enable
The SACSEN bit is used as an enable/disable for the SCSA pin. If this bit is low, then
the SCSA pin will be disabled and placed into other functions. If the bit is high the
SCSA pin will be enabled and used as a select pin.
Bit 1SAWCOL: Write Collision Bit
0: Collision free
1: Collision detected
The SAWCOL flag is used to detect if a data collision has occurred. If this bit is high
it means that data has been attempted to be written to the SPIAD register during a data
transfer operation. This writing operation will be ignored if data is being transferred.
The bit can be cleared by the application program. Note that this function can be
disabled or enabled via the SA_WCOL bit in the SBSC register.
Bit 0SATRF: Transmit/Receive Flag
0: Not complete
1: Transmission/reception complete
The SATRF bit is the Transmit/Receive Complete flag and is set "1" automatically
when an SPIA data transmission is completed, but must set to zero by the application
program. It can be used to generate an interrupt.
Rev. 1.40
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HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
SBSC Register
Bit
7
Name SIM_WCOL
6
5
4
3
2
1
0
—
I2CDB1
I2CDB0
—
—
—
SA_WCOL
R/W
R/W
—
R/W
R/W
—
—
—
R/W
POR
0
—
0
0
—
—
—
0
Bit 7: SIM_WCOL: SIM WCOL control bit
Related to SPI, described elsewhere. Bit 6: Unimplemented, read as "0"
Bit 5, 4:I2CDB1, I2CDB0: I2C debounce selection bits
Related to I2C, described elsewhere. Bit 3~1:
Unimplemented, read as "0"
Bit 0: SA_WCOL: SPIA WCOL function control
0: Disable
1: Enable
SPIA Communication
After the SPIA interface is enabled by setting the SPIAEN bit high, then in the Master Mode, when
data is written to the SPIAD register, transmission/reception will begin simultaneously. When the
data transfer is complete, the SATRF flag will be set automatically, but must be cleared using the
application program. In the Slave Mode, when the clock signal from the master has been received,
any data in the SPIAD register will be transmitted and any data on the SDIA pin will be shifted into
the SPIAD register.
The master should output an SCSA signal to enable the slave device before a clock signal is
provided. The slave data to be transferred should be well prepared at the appropriate moment
relative to the SCSA signal depending upon the configurations of the SACKPOL bit and SACKEG
bit. The accompanying timing diagram shows the relationship between the slave data and SCS signal
for various configurations of the SACKPOL and SACKEG bits.
The SPIA will continue to function even in the IDLE Mode.
Rev. 1.40
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HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
           ­  €
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SPIA Master Mode Timing
        ­    SPIA Slave Mode Timing – SACKEG=0
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SPIA Slave Mode Timing – SACKEG=1
Rev. 1.40
194
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
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   SPIA Transfer Control Flowchart
SPIA Bus Enable/Disable
To enable the SPIA bus, set SACSEN=1 and SCSA=0, then wait for data to be written into the
SPIAD (TXRX buffer) register. For the Master Mode, after data has been written to the SPIAD
(TXRX buffer) register, then transmission or reception will start automatically. When all the data has
been transferred the SATRF bit should be set. For the Slave Mode, when clock pulses are received
on SCKA, data in the TXRX buffer will be shifted out or data on SDIA will be shifted in.
To Disable the SPIA bus SCKA, SDIA, SDOA, SCSA will become I/O pins or the other functions.
Rev. 1.40
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A/D Flash USB 8-Bit MCU with SPI
SPIA Operation
All communication is carried out using the 4-line interface for either Master or Slave Mode.
The SACSEN bit in the SPIAC1 register controls the overall function of the SPIA interface. Setting
this bit high will enable the SPIA interface by allowing the SCSA line to be active, which can then
be used to control the SPIA interface. If the SACSEN bit is low, the SPIA interface will be disabled
and the SCSA line will be an I/O pin or the other functions and can therefore not be used for control
of the SPIA interface. If the SACSEN bit and the SPIAEN bit in the SPIAC0 register are set high,
this will place the SDIA line in a floating condition and the SDOA line high. If in Master Mode the
SCKA line will be either high or low depending upon the clock polarity selection bit SACKPOL in
the SPIAC1 register. If in Slave Mode the SCKA line will be in a floating condition. If SPIAEN is
low then the bus will be disabled and SCSA, SDIA, SDOA and SCKA will all become I/O pins or the
other functions. In the Master Mode the Master will always generate the clock signal. The clock and
data transmission will be initiated after data has been written into the SPIAD register. In the Slave
Mode, the clock signal will be received from an external master device for both data transmission
and reception. The following sequences show the order to be followed for data transfer in both
Master and Slave Mode.
Master Mode:
• Step 1
Select the clock source and Master mode using the SASPI2~SASPI0 bits in the SPIAC0 control
register.
• Step 2
Setup the SACSEN bit and setup the SAMLS bit to choose if the data is MSB or LSB first, this
must be same as the Slave device.
• Step 3
Setup the SPIAEN bit in the SPIAC0 control register to enable the SPIA interface.
• Step 4
For write operations: write the data to the SPIAD register, which will actually place the data into
the TXRX buffer. Then use the SCKA and SCSA lines to output the data. After this go to step 5.
For read operations: the data transferred in on the SDIA line will be stored in the TXRX buffer
until all the data has been received at which point it will be latched into the SPIAD register.
• Step 5
Check the SAWCOL bit if set high then a collision error has occurred so return to step 4. If equal
to zero then go to the following step.
• Step 6
Check the SATRF bit or wait for a SPIA serial bus interrupt.
• Step 7
Read data from the SPIAD register.
• Step 8
Clear SATRF.
• Step 9
Go to step 4.
Rev. 1.40
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A/D Flash USB 8-Bit MCU with SPI
Slave Mode:
• Step 1
Select the SPIA Slave mode using the SASPI2~SASPI0 bits in the SPIAC0 control register.
• Step 2
Setup the SACSEN bit and setup the SAMLS bit to choose if the data is MSB or LSB first, this
setting must be the same with the Master device.
• Step 3
Setup the SPIAEN bit in the SPIAC0 control register to enable the SPIA interface.
• Step 4
For write operations: write the data to the SPIAD register, which will actually place the data into
the TXRX buffer. Then wait for the master clock SCKA and SCSA signal. After this, go to step 5.
For read operations: the data transferred in on the SDIA line will be stored in the TXRX buffer
until all the data has been received at which point it will be latched into the SPIAD register.
• Step 5
Check the SAWCOL bit if set high then a collision error has occurred so return to step 4. If equal
to zero then go to the following step.
• Step 6
Check the SATRF bit or wait for a SPIA serial bus interrupt.
• Step 7
Read data from the SPIAD register.
• Step 8
Clear SATRF.
• Step 9
Go to step 4.
Error Detection
The SAWCOL bit in the SPIAC1 register is provided to indicate errors during data transfer. The bit
is set by the SPIA serial Interface but must be cleared by the application program. This bit indicates
a data collision has occurred which happens if a write to the SPIAD register takes place during a
data transfer operation and will prevent the write operation from continuing. The overall function of
the SAWCOL bit can be disabled or enabled by the SA_WCOL bit in the SBSC register.
Rev. 1.40
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A/D Flash USB 8-Bit MCU with SPI
Peripheral Clock Output
The Peripheral Clock Output allows the device to supply external hardware with a clock signal
synchronised to the microcontroller clock.
Peripheral Clock Operation
As the peripheral clock output pin, PCK, is shared with I/O line, the required pin function is chosen
via PCKEN in the SIMC0 register. The Peripheral Clock function is controlled using the SIMC0
register. The clock source for the Peripheral Clock Output can originate from either the TM0 CCRP
match frequency/2 or a divided ratio of the internal fSYS clock. The PCKEN bit in the SIMC0 register
is the overall on/off control, setting PCKEN bit to "1" enables the Peripheral Clock, setting PCKEN
bit to "0" disables it. The required division ratio of the system clock is selected using the PCKP1
and PCKP0 bits in the same register. If the device enters the SLEEP Mode this will disable the
Peripheral Clock output.
SIMC0 Register
Bit
7
6
5
4
3
2
1
0
Name
SIM2
SIM1
SIM0
PCKEN
PCKP1
PCKP0
SIMEN
—
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
—
POR
1
1
1
0
0
0
0
—
SIM2, SIM1, SIM0: SIM operating mode control
000: SPI master mode; SPI clock is fSYS/4
001: SPI master mode; SPI clock is fSYS/16
010: SPI master mode; SPI clock is fSYS/64
011: SPI master mode; SPI clock is fTBC (HT66FB540/550/560), fL (HT66FB542)
100: SPI master mode; SPI clock is TM0 CCRP match frequency/2
101: SPI slave mode
110: I2C slave mode
111: Non SIM function
These bits setup the overall operating mode of the SIM function. As well as selecting
if the I2C or SPI function, they are used to control the SPI Master/Slave selection and
the SPI Master clock frequency. The SPI clock is a function of the system clock but
can also be chosen to be sourced from the TM0 and fTBC (fL). If the SPI Slave Mode is
selected then the clock will be supplied by an external Master device.
Bit 4PCKEN: PCK output pin control
0: Disable
1: Enable
Bit 3~2
PCKP1, PCKP0: select PCK output pin frequency
00: fSYS
01: fSYS/4
10: fSYS/8
11: TM0 CCRP match frequency/2
Bit 1SIMEN: SIM control
0: Disable
1: Enable
The bit is the overall on/off control for the SIM interface. When the SIMEN bit is
cleared to zero to disable the SIM interface, the SDI, SDO, SCK and SCS, or SDA and
SCL lines will be in a floating condition and the SIM operating current will be reduced
to a minimum value. When the bit is high the SIM interface is enabled. Note that when
the SIMEN bit changes from low to high the contents of the SPI control registers will
be in an unknown condition and should therefore be first initialised by the application
program.
Bit 0
Unimplemented, read as "0"
Bit 7~5
Rev. 1.40
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A/D Flash USB 8-Bit MCU with SPI
Interrupts
Interrupts are an important part of any microcontroller system. When an external event or an
internal function such as a Timer Module or an A/D converter requires microcontroller attention,
their corresponding interrupt will enforce a temporary suspension of the main program allowing the
microcontroller to direct attention to their respective needs. The device contains several external
interrupt and internal interrupts functions. The external interrupts are generated by the action of the
external INT0~INT1 pins, while the internal interrupts are generated by various internal functions
such as the TMs, Comparators,Time Base, LVD, SIM , SPIA, USB, and the A/D converter.
Interrupt Registers
Overall interrupt control, which basically means the setting of request flags when certain
microcontroller conditions occur and the setting of interrupt enable bits by the application program,
is controlled by a series of registers, located in the Special Purpose Data Memory, as shown in the
accompanying table. The number of registers depends upon the device chosen but fall into three
categories. The first is the INTC0~INTC3 registers which setup the primary interrupts, the second
is the MFI0~MFI2 registers which setup the Multi-function interrupts. Finally there is an INTEG
register to setup the external interrupt trigger edge type.
Each register contains a number of enable bits to enable or disable individual registers as well as
interrupt flags to indicate the presence of an interrupt request. The naming convention of these
follows a specific pattern. First is listed an abbreviated interrupt type, then the (optional) number of
that interrupt followed by either an "E" for enable/disable bit or "F" for request flag.
Function
Enable Bit
Request Flag
Global
EMI
—
Notes
—
Comparator
CPnE
CPnF
n=0 for HT66FB542,
n=0 or 1 for HT66FB540/HT66FB550/HT66FB560
n=0 or 1
INTn Pin
INTnE
INTnF
A/D Converter
ADE
ADF
Multi-function
MFnE
MFnF
n=0~4
Time Base
TBnE
TBnF
n=0 or 1 only for HT66FB540/HT66FB550/HT66FB560
SIM
SIME
SIMF
—
SPIA
SPIAE
SPIAF
—
—
LVD
TM
USB
LVE
LVF
TnPE
TnPF
TnAE
TnAF
USBE
—
n=0~3
USBF
—
Interrupt Register Bit Naming Conventions
Rev. 1.40
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A/D Flash USB 8-Bit MCU with SPI
Interrupt Register Contents
• HT66FB542
Bit
Register
Name
7
6
5
4
3
2
1
0
INTEG
—
—
—
—
INT1S1
INT1S0
INT0S1
INT0S0
INTC0
—
USBF
INT1F
INT0F
USBE
INT1E
INT0E
EMI
INTC1
MF1F
MF0F
—
CP0F
MF1E
MF0E
—
CP0E
INTC2
SPIAF
SIMF
MF3F
MF2F
SPIAE
SIME
MF3E
MF2E
INTC3
—
MF4F
—
—
—
MF4E
—
—
MFI0
T1AF
T1PF
T0AF
T0PF
T1AE
T1PE
T0AE
T0PE
MFI1
T3AF
T3PF
T2AF
T2PF
T3AE
T3PE
T2AE
T2PE
MFI2
—
ADF
—
LVF
—
ADE
—
LVE
5
4
3
2
1
0
INT0S0
• HT66FB540/HT66FB550/HT66FB560
Name
Bit
7
6
INTEG
—
—
—
—
INT1S1
INT1S0
INT0S1
INTC0
—
USBF
INT1F
INT0F
USBE
INT1E
INT0E
EMI
INTC1
MF1F
MF0F
CP1F
CP0F
MF1E
MF0E
CP1E
CP0E
INTC2
SPIAF
SIMF
MF3F
MF2F
SPIAE
SIME
MF3E
MF2E
INTC3
—
MF4F
TB1F
TB0F
—
MF4E
TB1E
TB0E
MFI0
T1AF
T1PF
T0AF
T0PF
T1AE
T1PE
T0AE
T0PE
MFI1
T3AF
T3PF
T2AF
T2PF
T3AE
T3PE
T2AE
T2PE
MFI2
—
ADF
—
LVF
—
ADE
—
LVE
INTEG Register
Bit
7
6
5
4
3
2
1
0
Name
—
—
—
—
INT1S1
INT1S0
INT0S1
INT0S0
R/W
—
—
—
—
R/W
R/W
R/W
R/W
POR
—
—
—
—
0
0
0
0
Bit 7~4
Unimplemented, read as "0"
Bit 3~2INT1S1, INT1S0: interrupt edge control for INT1 pin
00: Disable
01: Rising edge
10: Falling edge
11: Rising and falling edges
Bit 1~0INT0S1, INT0S0: interrupt edge control for INT0 pin
00: Disable
01: Rising edge
10: Falling edge
11: Rising and falling edges
Rev. 1.40
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A/D Flash USB 8-Bit MCU with SPI
INTC0 Register
Bit
7
6
5
4
3
2
1
Name
—
USBF
INT1F
INT0F
USBE
INT1E
INT0E
EMI
R/W
—
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
—
0
0
0
0
0
0
0
Bit 7
0
Unimplemented, read as "0"
Bit 6USBF: USB Interrupt Request Flag
0: No request
1: Interrupt request
Bit 5INT1F: INT1 interrupt request flag
0: No request
1: Interrupt request
Bit 4INT0F: INT0 interrupt request flag
0: No request
1: Interrupt request
Bit 3USBE: USB Interrupt Control
0: Disable
1: Enable
Bit 2INT1E: INT1 interrupt control
0: Disable
1: Enable
Bit 1INT0E: INT0 interrupt control
0: Disable
1: Enable
Bit 0EMI: Global interrupt control
0: Disable
1: Enable
INTC1 Register
• HT66FB542
Bit
7
6
5
4
3
2
1
0
Name
MF1F
MF0F
—
CP0F
MF1E
MF0E
—
CP0E
R/W
R/W
R/W
—
R/W
R/W
R/W
—
R/W
POR
0
0
—
0
0
0
—
0
Bit 7MF1F: Multi-function interrupt 1 request flag
0: No request
1: Interrupt request
Bit 6MF0F: Multi-function interrupt 0 request flag
0: No request
1: Interrupt request
Bit 5
Unimplemented, read as “0”
Bit 4CP0F: Comparator 0 interrupt request flag
0: No request
1: Interrupt request
Bit 3MF1E: Multi-function interrupt 1 interrupt control
0: Disable
1: Enable
Bit 2MF0E: Multi-function interrupt 0 interrupt control
0: Disable
1: Enable
Rev. 1.40
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A/D Flash USB 8-Bit MCU with SPI
Bit 1
Unimplemented, read as “0”
Bit 0CP0E: Comparator 0 interrupt control
0: Disable
1: Enable
• HT66FB540/HT66FB550/HT66FB560
Bit
7
6
5
4
3
2
1
0
Name
MF1F
MF0F
CP1F
CP0F
MF1E
MF0E
CP1E
CP0E
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
0
0
0
0
0
0
0
Bit 7MF1F: Multi-function Interrupt 1 Request Flag
0: No request
1: Interrupt request
Bit 6MF0F: Multi-function Interrupt 0 Request Flag
0: No request
1: Interrupt request
Bit 5CP1F: Comparator 1 Interrupt Request Flag
0: no request
1: interrupt request
Bit 4CP0F: Comparator 0 Interrupt Request Flag
0: No request
1: Interrupt request
Bit 3MF1E: Multi-function Interrupt 1 Interrupt Control
0: Disable
1: Enable
Bit 2MF0E: Multi-function Interrupt 0 Interrupt Control
0: Disable
1: Enable
Bit 1CP1E: Comparator 1 Interrupt Control
0: Disable
1: Enable
Bit 0CP0E: Comparator 0 Interrupt Control
0: Disable
1: Enable
Rev. 1.40
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A/D Flash USB 8-Bit MCU with SPI
INTC2 Register
Bit
7
6
5
4
3
2
1
0
Name
SPIAF
SIMF
MF3F
MF2F
SPIAE
SIME
MF3E
MF2E
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
0
0
0
0
0
0
0
Bit 7SPIAF: SPIA interrupt request flag
0: No request
1: Interrupt request
Bit 6SIMF: SIM interrupt request flag
0: No request
1: Interrupt request
Bit 5MF3F: Multi-function Interrupt 3 Request Flag
0: No request
1: Interrupt request
Bit 4MF2F: Multi-function Interrupt 2 Request Flag
0: No request
1: Interrupt request
Bit 3SPIAE: SPIA Interrupt Control
0: Disable
1: Enable
Bit 2SIME: SIM Interrupt Control
0: Disable
1: Enable
Bit 1MF3E: Multi-function Interrupt 3 Control
0: Disable
1: Enable
Bit 0MF2E: Multi-function Interrupt 2 Control
0: Disable
1: Enable
INTC3 Register
• HT66FB542
Bit
7
6
5
4
3
2
1
0
Name
—
MF4F
—
—
—
MF4E
—
—
R/W
—
R/W
—
—
—
R/W
—
—
POR
—
0
—
—
—
0
—
—
Bit 7
Unimplemented, read as “0”
Bit 6MF4F: Multi-function interrupt 4 request flag
0: No request
1: Interrupt request
Bit 5~3
Unimplemented, read as “0”
Bit 2MF4E: Multi-function interrupt 4 control
0: Disable
1: Enable
Bit 1~0
Rev. 1.40
Unimplemented, read as “0”
203
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A/D Flash USB 8-Bit MCU with SPI
• HT66FB540/HT66FB550/HT66FB560
Bit
7
6
5
4
Name
—
MF4F
TB1F
R/W
—
R/W
R/W
POR
—
0
0
Bit 7
3
2
1
0
TB0F
—
MF4E
TB1E
TB0E
R/W
—
R/W
R/W
R/W
0
—
0
0
0
Unimplemented, read as "0"
Bit 6MF4F: Multi-function Interrupt 4 request flag
0: No request
1: Interrupt request
Bit 5TB1F: Time Base 1 Interrupt Request Flag
0: No request
1: Interrupt request
Bit 4TB0F: Time Base 0 Interrupt Request Flag
0: No request
1: Interrupt request
Bit 3
Unimplemented, read as "0"
Bit 2MF4E: Multi-function Interrupt 4 Control
0: Disable
1: Enable
Bit 1TB1E: Time Base 1 Interrupt Control
0: Disable
1: Enable
Bit 0TB0E: Time Base 0 Interrupt Control
0: Disable
1: Enable
Rev. 1.40
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A/D Flash USB 8-Bit MCU with SPI
MFI0 Register
Bit
7
6
5
4
3
2
1
0
Name
T1AF
T1PF
T0AF
T0PF
T1AE
T1PE
T0AE
T0PE
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
0
0
0
0
0
0
0
Bit 7T1AF: TM1 Comparator A match interrupt request flag
0: No request
1: Interrupt request
Bit 6T1PF: TM1 Comparator P match interrupt request flag
0: No request
1: Interrupt request
Bit 5T0AF: TM0 Comparator A match interrupt request flag
0: No request
1: Interrupt request
Bit 4T0PF: TM0 Comparator P match interrupt request flag
0: No request
1: Interrupt request
Bit 3T1AE: TM1 Comparator A match interrupt control
0: Disable
1: Enable
Bit 2T1PE: TM1 Comparator P match interrupt control
0: Disable
1: Enable
Bit 1T0AE: TM0 Comparator A match interrupt control
0: Disable
1: Enable
Bit 0T0PE: TM0 Comparator P match interrupt control
0: Disable
1: Enable
Rev. 1.40
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A/D Flash USB 8-Bit MCU with SPI
MFI1 Register
Bit
7
6
5
4
3
2
1
0
Name
T3AF
T3PF
T2AF
T2PF
T3AE
T3PE
T2AE
T2PE
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
0
0
0
0
0
0
0
Bit 7T3AF: TM3 Comparator A match interrupt request flag
0: No request
1: Interrupt request
Bit 6T3PF: TM3 Comparator P match interrupt request flag
0: No request
1: Interrupt request
Bit 5T2AF: TM2 Comparator A match interrupt request flag
0: No request
1: Interrupt request
Bit 4T2PF: TM2 Comparator P match interrupt request flag
0: No request
1: Interrupt request
Bit 3T3AE: TM3 Comparator A match interrupt control
0: Disable
1: Enable
Bit 2T3PE: TM3 Comparator P match interrupt control
0: Disable
1: Enable
Bit 1T2AE: TM2 Comparator A match interrupt control
0: Disable
1: Enable
Bit 0T2PE: TM2 Comparator P match interrupt control
0: Disable
1: Enable
Rev. 1.40
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A/D Flash USB 8-Bit MCU with SPI
MFI2 Register
Bit
7
6
5
Name
—
ADF
—
R/W
—
R/W
—
POR
—
0
—
0
Bit 7
4
3
2
1
0
LVF
—
ADE
—
LVE
R/W
—
R/W
—
R/W
—
0
—
0
Unimplemented, read as "0"
Bit 6ADF: A/D Converter interrupt request flag
0: No request
1: Interrupt request
Bit 5
Unimplemented, read as "0"
Bit 4LVF: LVD interrupt request flag
0: No request
1: Interrupt request
Bit 3
Unimplemented, read as "0"
Bit 2ADE: A/D Converter Interrupt Control
0: Disable
1: Enable
Bit 1
Unimplemented, read as "0"
Bit 0LVE: LVD Interrupt Control
0: Disable
1: Enable
Interrupt Operation
When the conditions for an interrupt event occur, such as a TM Comparator P or Comparator A
match or A/D conversion completion etc, the relevant interrupt request flag will be set. Whether
the request flag actually generates a program jump to the relevant interrupt vector is determined by
the condition of the interrupt enable bit. If the enable bit is set high then the program will jump to
its relevant vector; if the enable bit is zero then although the interrupt request flag is set an actual
interrupt will not be generated and the program will not jump to the relevant interrupt vector. The
global interrupt enable bit, if cleared to zero, will disable all interrupts.
When an interrupt is generated, the Program Counter, which stores the address of the next instruction
to be executed, will be transferred onto the stack. The Program Counter will then be loaded with a
new address which will be the value of the corresponding interrupt vector. The microcontroller will
then fetch its next instruction from this interrupt vector. The instruction at this vector will usually
be a "JMP" which will jump to another section of program which is known as the interrupt service
routine. Here is located the code to control the appropriate interrupt. The interrupt service routine
must be terminated with a "RETI", which retrieves the original Program Counter address from
the stack and allows the microcontroller to continue with normal execution at the point where the
interrupt occurred.
The various interrupt enable bits, together with their associated request flags, are shown in the
accompanying diagrams with their order of priority. Some interrupt sources have their own
individual vector while others share the same multi-function interrupt vector. Once an interrupt
subroutine is serviced, all the other interrupts will be blocked, as the global interrupt enable bit,
EMI bit will be cleared automatically. This will prevent any further interrupt nesting from occurring.
However, if other interrupt requests occur during this interval, although the interrupt will not be
immediately serviced, the request flag will still be recorded.
Rev. 1.40
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A/D Flash USB 8-Bit MCU with SPI
If an interrupt requires immediate servicing while the program is already in another interrupt service
routine, the EMI bit should be set after entering the routine, to allow interrupt nesting. If the stack
is full, the interrupt request will not be acknowledged, even if the related interrupt is enabled, until
the Stack Pointer is decremented. If immediate service is desired, the stack must be prevented from
becoming full. In case of simultaneous requests, the accompanying diagram shows the priority that
is applied. All of the interrupt request flags when set will wake-up the device if it is in SLEEP or
IDLE Mode, however to prevent a wake-up from occurring the corresponding flag should be set
before the device is in SLEEP or IDLE Mode.
xxF
xxF
xxE
Legend
Request Flag� no auto �eset in
I�R
Request Flag� auto �eset in
I�R
Inte��u�t
Na�e
Request
Flags
Ena�le
Bits
Maste�
Ena�le
Vector
Ena�le Bits
INT0 Pin
INT0F
INT0E
EMI
04H
INT1 Pin
INT1F
INT1E
EMI
0�H
U�B
U�BF
U�BE
EMI
0CH
Co��.0
CP0F
CP0E
EMI
10H
Unused
14H
Inte��u�t
Na�e
Request
Flags
Ena�le
Bits
EMI auto disa�led in I�R
Inte��u�ts contained within
Multi-Function Inte��u�ts
TM0 P
T0PF
T0PE
TM0 A
T0AF
T0AE
TM1 P
T1PF
T1PE
TM1 A
T1AF
T1AE
TM� P
T�PF
T�PE
TM� A
T�AF
T�AE
TM3 P
T3PF
T3PE
TM3 A
T3AF
T3AE
LVD
LVF
LVE
A/D
ADF
ADE
High
M. Funct. 0
MF0F
MF0E
EMI
1�H
M. Funct. 1
MF1F
MF1E
EMI
1CH
M. Funct. �
MF�F
MF�E
EMI
�0H
M. Funct. 3
MF3F
MF3E
EMI
�4H
�IM
�IMF
�IME
EMI
��H
�PIA
�PIAF
�PIAE
EMI
�CH
Unused
30H
Unused
34H
EMI
3�H
M. Funct. 4
MF4F
MF4E
P�io�ity
Low
Interrupt Structure – HT66FB542
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EMI auto disabled in ISR
Legend
xxF
Request Flag – no auto reset in ISR
xxF Request Flag – auto reset in ISR
xxE
Enable Bit
Interrupt Request
Name
Flags
Enable
Bits
Master
Enable
INT0 Pin
INT0F
INT0E
EMI
04H
INT1 Pin
INT1F
INT1E
EMI
08H
USB
USBF
USBE
EMI
0CH
Comp. 0
CP0F
CP0E
EMI
10H
Comp. 1
CP1F
CP1E
EMI
14H
Vector
Request
Flags
Enable
Bits
TM0 P
T0PF
T0PE
TM0 A
T0AF
T0AE
M. Funct. 0
MF0F
MF0E
EMI
18H
TM1 P
T1PF
T1PE
M. Funct. 1
MF1F
MF1E
EMI
1CH
TM1 A
T1AF
T1AE
TM2 P
T2PF
T2PE
M. Funct. 2
MF2F
MF2E
EMI
20H
TM2 A
T2AF
T2AE
TM3 P
T3PF
T3PE
M. Funct. 3
MF3F
MF3E
EMI
24H
TM3 A
T3AF
T3AE
SIM
SIMF
SIME
EMI
28H
SPIA
SPIAF
SPIAE
EMI
2CH
Time Base 0
TB0F
TB0E
EMI
30H
Time Base 1
TB1F
TB1E
EMI
34H
M. Funct. 4
MF4F
MF4E
EMI
38H
Interrupt
Name
LVD
LVF
LVE
A/D
ADF
ADE
Interrupts contained within
Multi-Function Interrupts
Priority
High
Low
Interrupt Structure – HT66FB540/HT66FB550/HT66FB560
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External Interrupt
The external interrupts are controlled by signal transitions on the pins INT0 and INT1. An external
interrupt request will take place when the external interrupt request flags, INT0F, INT1F, are set,
which will occur when a transition, whose type is chosen by the edge select bits, appears on the
external interrupt pins. To allow the program to branch to its respective interrupt vector address, the
global interrupt enable bit, EMI, and respective external interrupt enable bit, INT0E, INT1E, must
first be set. Additionally the correct interrupt edge type must be selected using the INTEG register to
enable the external interrupt function and to choose the trigger edge type. As the external interrupt
pins are pin-shared with I/O pins, they can only be configured as external interrupt pins if their
external interrupt enable bit in the corresponding interrupt register has been set. The pin must also
be setup as an input by setting the corresponding bit in the port control register. When the interrupt
is enabled, the stack is not full and the correct transition type appears on the external interrupt pin,
a subroutine call to the external interrupt vector, will take place. When the interrupt is serviced, the
external interrupt request flags, INT0F, INT1F, will be automatically reset and the EMI bit will be
automatically cleared to disable other interrupts. Note that any pull-high resistor selections on the
external interrupt pins will remain valid even if the pin is used as an external interrupt input.
The INTEG register is used to select the type of active edge that will trigger the external interrupt.
A choice of either rising or falling or both edge types can be chosen to trigger an external interrupt.
Note that the INTEG register can also be used to disable the external interrupt function.
Comparator Interrupt
The comparator interrupts are controlled by the two internal comparators. A comparator interrupt
request will take place when the comparator interrupt request flags, CP0F or CP1F, are set, a
situation that will occur when the comparator output bit changes state. To allow the program to
branch to its respective interrupt vector address, the global interrupt enable bit, EMI, and comparator
interrupt enable bits, CP0E and CP1E, must first be set. When the interrupt is enabled, the stack is
not full and the comparator inputs generate a comparator output transition, a subroutine call to the
comparator interrupt vector, will take place. When the interrupt is serviced, the comparator interrupt
request flags, CP0F, CP1F, will be automatically reset and the EMI bit will be automatically cleared
to disable other interrupts.
Note that the HT66FB542 device has only comparator 0 interrupt function.
USB Interrupt
A USB interrupt request will take place when the USB interrupt request flag, USBF, is set, a
situation that will occur when an endpoint is accessed. To allow the program to branch to its
respective interrupt vector address, the global interrupt enable bit, EMI, and USB interrupt enable
bit, USBE, must first be set. When the interrupt is enabled, the stack is not full and an endpoint
is accessed, a subroutine call to the USB interrupt vector, will take place. When the interrupt is
serviced, the USB interrupt request flag, USBF, will be automatically reset and the EMI bit will be
automatically cleared to disable other interrupts.
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Multi-function Interrupt
Within these devices there are up to five Multi-function interrupts. Unlike the other independent
interrupts, these interrupts have no independent source, but rather are formed from other existing
interrupt sources, namely the TM Interrupts, ADC Interrupt and LVD Interrupt.
A Multi-function interrupt request will take place when any of the Multi-function interrupt request
flags, MF0F~MF4F are set. The Multi-function interrupt flags will be set when any of their included
functions generate an interrupt request flag. To allow the program to branch to its respective
interrupt vector address, when the Multi-function interrupt is enabled and the stack is not full, and
either one of the interrupts contained within each of Multi-function interrupt occurs, a subroutine
call to one of the Multi-function interrupt vectors will take place. When the interrupt is serviced, the
related Multi-Function request flag will be automatically reset and the EMI bit will be automatically
cleared to disable other interrupts.
However, it must be noted that, although the Multi-function Interrupt flags will be automatically
reset when the interrupt is serviced, the request flags from the original source of the Multi-function
interrupts, namely the TM Interrupts, ADC Interrupt and LVD interrupt will not be automatically
reset and must be manually reset by the application program.
A/D Converter Interrupt
The A/D Converter Interrupt is contained within the Multi-function Interrupt. An A/D Converter
Interrupt request will take place when the A/D Converter Interrupt request flag, ADF, is set, which
occurs when the A/D conversion process finishes. To allow the program to branch to its respective
interrupt vector address, the global interrupt enable bit, EMI, and A/D Interrupt enable bit, ADE, and
associated Multi-function interrupt enable bit, must first be set. When the interrupt is enabled, the
stack is not full and the A/D conversion process has ended, a subroutine call to the Multi-function
Interrupt vector, will take place. When the A/D Converter Interrupt is serviced, the EMI bit will be
automatically cleared to disable other interrupts, however only the Multi-function interrupt request
flag will be also automatically cleared. As the ADF flag will not be automatically cleared, it has to
be cleared by the application program.
Time Base Interrupts – HT66FB540/HT66FB550/HT66FB560
The function of the Time Base Interrupts is to provide regular time signal in the form of an internal
interrupt. They are controlled by the overflow signals from their respective timer functions. When
these happens their respective interrupt request flags, TB0F or TB1F will be set. To allow the
program to branch to their respective interrupt vector addresses, the global interrupt enable bit, EMI
and Time Base enable bits, TB0E or TB1E, must first be set. When the interrupt is enabled, the stack
is not full and the Time Base overflows, a subroutine call to their respective vector locations will
take place. When the interrupt is serviced, the respective interrupt request flag, TB0F or TB1F, will
be automatically reset and the EMI bit will be cleared to disable other interrupts.
The purpose of the Time Base Interrupt is to provide an interrupt signal at fixed time periods. Their
clock sources originate from the internal clock source fTB. This fTB input clock passes through a
divider, the division ratio of which is selected by programming the appropriate bits in the TBC
register to obtain longer interrupt periods whose value ranges. The clock source that generates fTB,
which in turn controls the Time Base interrupt period, can originate from several different sources,
as shown in the System Operating Mode section.
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TBC Register
Bit
7
6
5
4
3
2
1
0
Name
TBON
TBCK
TB11
TB10
LXTLP
TB02
TB01
TB00
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
0
1
1
0
1
1
1
Bit 7TBON: TB0 and TB1 Control
0: Disable
1: Enable
Bit 6TBCK: Select fTB Clock
0: fTBC
1: fSYS/4
Bit 5~4TB11~TB10: Select Time Base 1 Time-out Period
00: 4096/fTB
01: 8192/fTB
10: 16384/fTB
11: 32768/fTB
Bit 3LXTLP: LXT Low Power Control
0: Disable
1: Enable
Bit 2~0TB02~TB00: Select Time Base 0 Time-out Period
000: 256/fTB
001: 512/fTB
010: 1024/fTB
011: 2048/fTB
100: 4096/fTB
101: 8192/fTB
110: 16384/fTB
111: 32768/fTB
      Time Base Interrupts
Serial Interface Module Interrupts – SIM Interrupt
The Serial Interface Module Interrupt, also known as the SIM interrupt, will take place when the
SIM Interrupt request flag, SIMF, is set, which occurs when a byte of data has been received or
transmitted by the SIM interface or an I2C slave address match, or an I2C bus time-out occurrs. To
allow the program to branch to its respective interrupt vector address, the global interrupt enable
bit, EMI, and the Serial Interface Interrupt enable bit, SIME, must first be set. When the interrupt is
enabled, the stack is not full and any of the above described situations occurs, a subroutine call to
the respective Interrupt vector, will take place. When the interrupt is serviced, the Serial Interface
Interrupt flag, SIMF, will be automatically cleared. The EMI bit will also be automatically cleared to
disable other interrupts.
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Serial Peripheral Interface Interrupt – SPIA Interrupt
The Serial Peripheral Interface Interrupt, also known as the SPIA interrupt, will take place when the
SPIA Interrupt request flag, SPIAF, is set, which occurs when a byte of data has been received or
transmitted by the SPIA interface. To allow the program to branch to its respective interrupt vector
address, the global interrupt enable bit, EMI, and the Serial Interface Interrupt enable bit, SPIAE,
must first be set. When the interrupt is enabled, the stack is not full and a byte of data has been
transmitted or received by the SPIA interface, a subroutine call to the respective Interrupt vector,
will take place. When the interrupt is serviced, the Serial Interface Interrupt flag, SPIAF, will be
automatically cleared. The EMI bit will also be automatically cleared to disable other interrupts.
LVD Interrupt
The Low Voltage Detector Interrupt is contained within the Multi-function Interrupt. An LVD
Interrupt request will take place when the LVD Interrupt request flag, LVF, is set, which occurs
when the Low Voltage Detector function detects a low power supply voltage. To allow the program
to branch to its respective interrupt vector address, the global interrupt enable bit, EMI, Low Voltage
Interrupt enable bit, LVE, and associated Multi-function interrupt enable bit, must first be set. When
the interrupt is enabled, the stack is not full and a low voltage condition occurs, a subroutine call to
the Multi-function Interrupt vector, will take place. When the Low Voltage Interrupt is serviced, the
EMI bit will be automatically cleared to disable other interrupts, however only the Multi-function
interrupt request flag will be also automatically cleared. As the LVF flag will not be automatically
cleared, it has to be cleared by the application program.
TM Interrupts
The Compact and Standard Type TMs have two interrupts each. All of the TM interrupts are
contained within the Multi-function Interrupts. For each of the Compact and Standard Type TMs
there are two interrupt request flags TnPF and TnAF and two enable bits TnPE and TnAE. A TM
interrupt request will take place when any of the TM request flags are set, a situation which occurs
when a TM comparator P or A match situation happens.
To allow the program to branch to its respective interrupt vector address, the global interrupt enable
bit, EMI, respective TM Interrupt enable bit, and relevant Multi-function Interrupt enable bit, MFnE,
must first be set. When the interrupt is enabled, the stack is not full and a TM comparator match
situation occurs, a subroutine call to the relevant Multi-function Interrupt vector locations, will take
place. When the TM interrupt is serviced, the EMI bit will be automatically cleared to disable other
interrupts, however only the related MFnF flag will be automatically cleared. As the TM interrupt
request flags will not be automatically cleared, they have to be cleared by the application program.
Interrupt Wake-up Function
Each of the interrupt functions has the capability of waking up the microcontroller when in the
SLEEP or IDLE Mode. A wake-up is generated when an interrupt request flag changes from low to
high and is independent of whether the interrupt is enabled or not. Therefore, even though the device
is in the SLEEP or IDLE Mode and its system oscillator stopped, situations such as external edge
transitions on the external interrupt pins, a low power supply voltage or comparator input change
may cause their respective interrupt flag to be set high and consequently generate an interrupt. Care
must therefore be taken if spurious wake-up situations are to be avoided. If an interrupt wake-up
function is to be disabled then the corresponding interrupt request flag should be set high before the
device enters the SLEEP or IDLE Mode. The interrupt enable bits have no effect on the interrupt
wake-up function.
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Programming Considerations
By disabling the relevant interrupt enable bits, a requested interrupt can be prevented from being
serviced, however, once an interrupt request flag is set, it will remain in this condition in the
interrupt register until the corresponding interrupt is serviced or until the request flag is cleared by
the application program.
Where a certain interrupt is contained within a Multi-function interrupt, then when the interrupt
service routine is executed, as only the Multi-function interrupt request flags, MF0F~MF4F, will
be automatically cleared, the individual request flag for the function needs to be cleared by the
application program.
It is recommended that programs do not use the "CALL" instruction within the interrupt service
subroutine. Interrupts often occur in an unpredictable manner or need to be serviced immediately.
If only one stack is left and the interrupt is not well controlled, the original control sequence will be
damaged once a CALL subroutine is executed in the interrupt subroutine.
Every interrupt has the capability of waking up the microcontroller when it is in the SLEEP or IDLE
Mode, the wake up being generated when the interrupt request flag changes from low to high. If it is
required to prevent a certain interrupt from waking up the microcontroller then its respective request
flag should be first set high before enter SLEEP or IDLE Mode.
As only the Program Counter is pushed onto the stack, then when the interrupt is serviced, if the
contents of the accumulator, status register or other registers are altered by the interrupt service
program, their contents should be saved to the memory at the beginning of the interrupt service
routine.
To return from an interrupt subroutine, either a RET or RETI instruction may be executed. The RETI
instruction in addition to executing a return to the main program also automatically sets the EMI
bit high to allow further interrupts. The RET instruction however only executes a return to the main
program leaving the EMI bit in its present zero state and therefore disabling the execution of further
interrupts.
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Low Voltage Detector – LVD
Each device has a Low Voltage Detector function, also known as LVD. This enabled the device to
monitor the power supply voltage, VDD, and provide a warning signal should it fall below a certain
level. This function may be especially useful in battery applications where the supply voltage will
gradually reduce as the battery ages, as it allows an early warning battery low signal to be generated.
The Low Voltage Detector also has the capability of generating an interrupt signal.
LVD Register
The Low Voltage Detector function is controlled using a single register with the name LVDC. Three
bits in this register, VLVD2~VLVD0, are used to select one of eight fixed voltages below which
a low voltage condition will be determined. A low voltage condition is indicated when the LVDO
bit is set. If the LVDO bit is low, this indicates that the VDD voltage is above the preset low voltage
value. The LVDEN bit is used to control the overall on/off function of the low voltage detector.
Setting the bit high will enable the low voltage detector. Clearing the bit to zero will switch off the
internal low voltage detector circuits. As the low voltage detector will consume a certain amount of
power, it may be desirable to switch off the circuit when not in use, an important consideration in
power sensitive battery powered applications.
LVDC Register
Bit
7
6
5
4
3
2
1
0
Name
—
—
LVDO
LVDEN
—
VLVD2
VLVD1
VLVD0
R/W
—
—
R
R/W
—
R/W
R/W
R/W
POR
—
—
0
0
—
0
0
0
Bit 7~6
Unimplemented, read as "0"
Bit 5LVDO: LVD Output Flag
0: No Low Voltage Detect
1: Low Voltage Detect
Bit 4LVDEN: Low Voltage Detector Control
0: Disable
1: Enable
Bit 3
Unimplemented, read as "0"
Bit 2~0VLVD2~VLVD0: Select LVD Voltage
000: 2.0V
001: 2.2V
010: 2.4V
011: 2.7V
100: 3.0V
101: 3.3V
110: 3.6V
111: 4.0V
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LVD Operation
The Low Voltage Detector function operates by comparing the power supply voltage, VDD, with a
pre-specified voltage level stored in the LVDC register. This has a range of between 2.0V and 4.0V.
When the power supply voltage, VDD, falls below this pre-determined value, the LVDO bit will be
set high indicating a low power supply voltage condition. The Low Voltage Detector function is
supplied by a reference voltage which will be automatically enabled. When the device is powered
down the low voltage detector will remain active if the LVDEN bit is high. After enabling the Low
Voltage Detector, a time delay tLVDS should be allowed for the circuitry to stabilise before reading the
LVDO bit. Note also that as the VDD voltage may rise and fall rather slowly, at the voltage nears that
of VLVD, there may be multiple bit LVDO transitions.
VDD
VLVD
LVDEN
LVDO
tLVD�
LVD Operation
The Low Voltage Detector also has its own interrupt which is contained within one of the
Multi-function interrupts, providing an alternative means of low voltage detection, in addition to
polling the LVDO bit. The interrupt will only be generated after a delay of tLVD after the LVDO bit
has been set high by a low voltage condition. When the device is powered down the Low Voltage
Detector will remain active if the LVDEN bit is high. In this case, the LVF interrupt request flag
will be set, causing an interrupt to be generated if VDD falls below the preset LVD voltage. This will
cause the device to wake-up from the SLEEP or IDLE Mode, however if the Low Voltage Detector
wake up function is not required then the LVF flag should be first set high before the device enters
the SLEEP or IDLE Mode.
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USB Interface
The USB interface is a 4-wire serial bus that allows communication between a host device and up
to 127 max peripheral devices on the same bus. A token based protocol method is used by the host
device for communication control. Other advantages of the USB bus include live plugging and
unplugging and dynamic device configuration. As the complexity of USB data protocol does not
permit comprehensive USB operation information to be provided in this datasheet, the reader should
therefore consult other external information for a detailed USB understanding.
The devices include a USB interface function allowing for the convenient design of USB peripheral
products.
The USB disable/enable control bit "USBdis" is in the SYSC Register. If the USB is disabled, then
V33O will be floating, the UDP/UDN lines will become I/O functions, and the USB SIE will be
disabled.
Power Plane
There are three power planes for HT66FB540/HT66FB542/HT66FB550/HT66FB560: USB SIE
VDD, VDDIO and the MCU VDD.
For the USB SIE VDD will supply all circuits related to USB SIE and be sourced from pin "UBUS".
Once the USB is removed from the USB interface and there is no power in the USB BUS, the USB
SIE circuit is no longer operational.
For the PA port, it can be configured using the PAPS1 and PAPS0 registers to define the pins
PA0~PA7 are supplied by either the MCU VDD, the V33O or the power pin VDDIO.
The PE0 is pin-shared with VDDIO and VREF pins .The VDDIO function can be selected by
configuration option and the VREF function can be selected by the VREFS bit in the ADCR1
register. However, the VREF has the highest priority. If the VREF function has been selected, the
PE0 pin function will be disabled as well the VDDIO function, even though the VDDIO is selected. For the MCU VDD, it supplies all the HT66FB540/HT66FB542/HT66FB550/HT66FB560 circuits
except the USB SIE which is supply by UBUS.
The PE1 is pin shared with UBUS pin and it’s "input" only.
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USB Suspend Wake-Up Remote Wake-Up
If there is no signal on the USB bus for over 3ms, the devices will go into a suspend mode. The
Suspend flag, SUSP, in the USC register, will then be set high and an USB interrupt will be
generated to indicate that the devices should jump to the suspend state to meet the requirements
of the USB suspend current spec. In order to meet the requirements of the suspend current, the
firmware should disable the USB clock by clearing the USBCKEN bit to "0".
The suspend current can be further decreased by setting the SUSP2 bit in the UCC register. When
the resume signal is sent out by the host, the devices will be woken up the by the USB interrupt and
the Resume bit in the USC register will be set. To ensure correct device operation, the program must
set the USBCKEN bit in the UCC register high and clear the SUSP2 bit in the UCC register. The
Resume signal will be cleared before the Idle signal is sent out by the host and the Suspend line in
the USC register will change to zero. So when the MCU detects the Suspend bit in the USC register,
the condition of the Resume line should be noted and taken into consideration.
The devices have a remote wake up function which can wake-up the USB Host by sending a
wake-up pulse through RMWK in the USC register. Once the USB Host receives a wake-up signal
from the device it will send a Resume signal to the devices.
S U S P E N D
M in . 1
U S B C L K
R M O T _ W K
U S B R e s u m e S ig n a l
M in . 2 .5 m s
U S B _ IN T
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USB Interface Operation
The HT66FB540, HT66FB542, HT66FB550 and HT66FB560 have 4 Endpoints (EP0~EP3), 4
Endpoints (EP0~EP3), 6 Endpoints (EP0~EP5), and 8 Endpoints (EP0~EP7) respectively. The EP0
supports Control transfer. All EP1~EP7 support Interrupt or Bulk transfer.
All endpoints except EP0 can be configure as 8, 16, 32, 64 FIFO size by the register UFC0 and
UFC1. EP0 has 8-byte FIFO size.
The Total FIFO size is 384+8 bytes for the HT66FB540, 256+8 bytes for the HT66FB542, 640+8
bytes for the HT66FB550 and 896+8 bytes for the HT66FB560.
As the USB FIFO is assigned from the last bank of the Data RAM and has a start address of 0FFH
to the upper address, dependent on the FIFO size, if the corresponding data RAM bank is used for
both general purpose RAM and the USB FIFO, special care should be taken that the RAM EQU
definition should not overlap with the USB FIFO RAM address.
The URD in the USC register is the USB reset signal control function definition bit.
The USB FIFO size definition for IN/OUT control depends on the UFC0, UFC1, UFIEN and
UFOEN registers. If OUT 1 not used, then the OUT 1 FIFO will not be defined and IN 2 will be
defined as IN 1 afterwards.
HT66FB540
n�0H
Gene�al Pu��ose
Data Me�o�y
nBFH
nC0H
OUT 3 (� �ytes)
nC7H
nC�H
IN 3 (� �ytes)
nCFH
nD0H
OUT � (16 �ytes)
nDFH
nE0H
IN � (16 �ytes)
nEFH
nF0H
OUT 1 (� �ytes)
nF7H
nF�H
IN 1 (� �ytes)
nFFH
"n"=Bank 3~0� last �ank fi�st defined
USB FIFO Size Define
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USB Interface Registers
The USB interface has a series of registers associated with its operation.
SYSC Register
Bit
7
6
5
4
3
2
1
Name
CLK_ADJ
USBdis
RUBUS
R/W
R/W
R/W
R/W
POR
0
0
0
—
0
—
—
HFV
—
—
—
—
R/W
—
—
—
0
—
—
Bit 7CLK_ADJ: PLL Clock Automatic Adjustment function
PLL related control bit, described elsewhere
Bit 6USBdis: USB SIE control bit
0: Enable
1: Disable
Bit 5RUBUS: UBUS pin pull low resistor
0: Enable
1: Disable
Bit 4~3 unimplemented, read as "0"
Bit 2 HFV: Non-USB mode high frequency voltage control
0: For USB mode - bit must be cleared to zero.
1: For non-USB mode - bit must be set high. Ensures that the higher frequency
can work at lower voltages.
A higher frequency is >8MHz and is used for the system clock fH.
Bit 1~0 unimplemented, read as "0"
USB_STAT Register
Bit
Name
7
6
5
4
PS2_CKO PS2_DAO PS2_CKI PS2_DAI
3
2
1
0
SE1
SE0
PU
ESD
R/W
W
W
R
R
R/W
R/W
R/W
R/W
POR
1
1
x
x
0
0
0
x
“x”: unknown
Bit 7PS2_CKO: Output for driving UDP/GPIO1 pin, when work under GPIO mode
function. Default value is "1".
Bit 6PS2_DAO: Output for driving UDN/GPIO0 pin, when work under GPIO mode
function. Default value is "1".
Bit 5PS2_CKI: UDP/GPIO1 input
Bit 4PS2_DAI: UDN/GPIO0 input
Bit 3SE1 : This bit is used to indicate the SIE has detected a SE1 noise in the USB bus.
This bit is set by SIE and clear by F/W.
Bit 2SE0 : This bit is used to indicate the SIE has detected a SE0 noise in the USB bus.
This bit is set by SIE and clear by F/W.
Bit 1PU:
Bit1=1, UDP and UDN have a 600kΩ pull-high
Bit1=0, no pull-high (default on MCU reset)
Bit 0
Rev. 1.40
This bit will set to "1" when there is ESD issue.
This bit is set by SIE and cleared by F/W.
220
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
UINT Register
• HT66FB540/HT66FB542
Bit
7
6
5
4
3
2
1
0
Name
—
—
—
—
EP3EN
EP2EN
EP1EN
EP0EN
R/W
—
—
—
—
R/W
R/W
R/W
R/W
POR
—
—
—
—
0
0
0
0
Bit 7~4
Unimplemented, read as "0"
Bit 3EP3EN: USB endpoint3 interrupt control bit.
0: Disable
1: Enable
Bit 2EP2EN: USB endpoint2 interrupt control bit.
0: Disable
1: Enable
Bit 1EP1EN: USB endpoint1 interrupt control bit.
0: Disable
1: Enable
Bit 0EP0EN: USB endpoint0 interrupt control bit.
0: Disable
1: Enable
• HT66FB550
Bit
7
6
5
4
3
2
1
0
Name
—
—
EP5EN
EP4EN
EP3EN
EP2EN
EP1EN
EP0EN
R/W
—
—
R/W
R/W
R/W
R/W
R/W
R/W
POR
—
—
0
0
0
0
0
0
Bit 7~6
Unimplemented, read as "0"
Bit 5EP5EN: USB endpoint5 interrupt control bit
0: Disable
1: Enable
Bit 4EP4EN: USB endpoint4 interrupt control bit
0: Disable
1: Enable
Bit 3EP3EN: USB endpoint3 interrupt control bit
0: Disable
1: Enable
Bit 2EP2EN: USB endpoint2 interrupt control bit
0: Disable
1: Enable
Bit 1EP1EN: USB endpoint1 interrupt control bit
0: Disable
1: Enable
Bit 0EP0EN: USB endpoint0 interrupt control bit
0: Disable
1: Enable
Rev. 1.40
221
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
• HT66FB560
Bit
7
6
5
4
3
2
1
0
Name
EP7EN
EP6EN
EP5EN
EP4EN
EP3EN
EP2EN
EP1EN
EP0EN
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
0
0
0
0
0
0
0
3
2
1
0
Bit 7EP7EN: USB endpoint7 interrupt control bit
0: Disable
1: Enable
Bit 6EP6EN: USB endpoint6 interrupt control bit
0: Disable
1: Enable
Bit 5EP5EN: USB endpoint5 interrupt control bit
0: Disable
1: Enable
Bit 4EP4EN: USB endpoint4 interrupt control bit
0: Disable
1: Enable
Bit 3EP3EN: USB endpoint3 interrupt control bit
0: Disable
1: Enable
Bit 2EP2EN: USB endpoint2 interrupt control bit
0: Disable
1: Enable
Bit 1EP1EN: USB endpoint1 interrupt control bit
0: Disable
1: Enable
Bit 0EP0EN: USB endpoint0 interrupt control bit
0: Disable
1: Enable
USC Register
Bit
7
6
5
4
Name
URD
SELPS2
PLL
URST
RMWK
SUSP
R/W
R/W
R/W
R/W
R/W
R
R/W
R/W
R
POR
1
0
0
0
x
x
x
SELUSB RESUME
x
“x”: unknown
Bit 7URD: USB reset signal control function definition
0: USB reset signal cannot reset MCU
1: USB reset signal will reset MCU
Bit 6SELPS2: PS2 mode select bit
0: Not PS2 mode
1: PS2 mode
When the SELPS2 bit is set high, the PS2 function is selected and the pin-shared pins,
UDN/GPIO0 and UDP/GPIO1, will become the GPIO0 and GPIO1 general purpose
I/O functions which can be used to be the DATA and CLK pins for the PS2.
Bit 5PLL: PLL control bit
0: Turn-on PLL
1: Turn-off PLL
Rev. 1.40
222
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
Bit 4SELUSB: USB mode and V33O on/off select bit
0: Not USB mode, Turn-off V33O
1: USB mode, Turn-on V33O
When the SELUSB bit is set high, the USB and V33O functions are selected and the
pin-share pins, UDN/GPIO0 and UDP/GPIO1, will become the UDN and UDP pins
for the USB.
Bit 3RESUME: USB resume indication bit
0: SUSP bit goes to "0"
1: Leave the suspend mode
When the USB leaves the suspend mode, this bit is set to "1" (set by SIE). When the
RESUME is set by SIE, an interrupt will be generated to wake-up the MCU. In order
to detect the suspend state, the MCU should set USBCKEN and clear SUSP2 (in the
UCC register) to enable the SIE detect function. RESUME will be cleared when the
SUSP goes to "0". When the MCU is detecting the SUSP, the condition of RESUME
(causes the MCU to wake-up) should be noted and taken into consideration.
Bit 2URST: USB reset indication bit
0: No USB reset
1: USB reset occurred
This bit is set/cleared by the USB SIE. This bit is used to detect a USB reset event on
the USB bus. When this bit is set to "1", this indicates that a USB reset has occurred
and that a USB interrupt will be initialized.
Bit 1RMWK: USB remote wake-up command
0: No remote wake-up
1: Remote wake-up
It is set by MCU to leave the USB host leaving the suspend mode. Set RMWK bit to
1 to initiate the remote wake-up command. This bit is set to produce a high pulse to
indicate that the USB host has left the suspend mode.
Bit 0SUSP: USB suspend indication
0: Not in the suspend mode
1: Enter the suspend mode
When this bit is set to 1 (set by SIE), it indicates that the USB bus has entered the
suspend mode. The USB interrupt is also triggered when this bit changes from low to
high.
SELUSB
SELPS2
USB and PS2 mode description
0
0
1. No mode supported
2. V33O pin not output and it will floating
3. UDN/GPIO0 and UDP/GPIO1 pins cann’t output
0
1
1. PS2 mode
2. V33O pin output VDD
3. UDN/GPIO0 and UDP/GPIO1 pins will become the GPIO0 and GPIO1
pins, which can output by firmware
1
x
1. USB mode
2. V33O output 3.3V
3. UDN/GPIO0 and UDP/GPIO1 pins will become the UDN and UDP pins
x: don’t care
Rev. 1.40
223
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
USR Register
• HT66FB540/HT66FB542
Bit
7
6
5
4
3
2
1
0
Name
—
—
—
—
EP3F
EP2F
EP1F
EP0F
R/W
—
—
—
—
R/W
R/W
R/W
R/W
POR
—
—
—
—
x
x
x
x
“x”: unknown
Bit 7~4
Unimplemented, read as "0"
Bit 3EP3F: Endpoint 3 accessed detection
0: Not accessed
1: Accessed
Bit 2EP2F: Endpoint 2 accessed detection
0: Not accessed
1: Accessed
Bit 1EP1F: Endpoint 1 accessed detection
0: Not accessed
1: Accessed
Bit 0EP0F: Endpoint 0 accessed detection
0: Not accessed
1: Accessed
• HT66FB550
Bit
7
6
5
4
3
2
1
0
Name
—
—
EP5F
EP4F
EP3F
EP2F
EP1F
EP0F
R/W
—
—
R/W
R/W
R/W
R/W
R/W
R/W
POR
—
—
x
x
x
x
x
x
“x”: unknown
Bit 7~6
Unimplemented, read as "0"
Bit 5EP5F: Endpoint 5 accessed detection
0: Not accessed
1: Accessed
Bit 4EP4F: Endpoint 4 accessed detection
0: Not accessed
1: Accessed
Bit 3EP3F: Endpoint 3 accessed detection
0: Not accessed
1: Accessed
Bit 2EP2F: Endpoint 2 accessed detection
0: Not accessed
1: Accessed
Bit 1EP1F: Endpoint 1 accessed detection
0: Not accessed
1: Accessed
Bit 0EP0F: Endpoint 0 accessed detection
0: Not accessed
1: Accessed
Rev. 1.40
224
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
• HT66FB560
Bit
7
6
5
4
3
2
1
0
Name
EP7F
EP6F
EP5F
EP4F
EP3F
EP2F
EP1F
EP0F
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
x
x
x
x
x
x
x
x
“x”: unknown
Bit 7EP7F: Endpoint 7 accessed detection
0: Not accessed
1: Accessed
Bit 6EP6F: Endpoint 6 accessed detection
0: Not accessed
1: Accessed
Bit 5EP5F: Endpoint 5 accessed detection
0: Not accessed
1: Accessed
Bit 4EP4F: Endpoint 4 accessed detection
0: Not accessed
1: Accessed
Bit 3EP3F: Endpoint 3 accessed detection
0: Not accessed
1: Accessed
Bit 2EP2F: Endpoint 2 accessed detection
0: Not accessed
1: Accessed
Bit 1EP1F: Endpoint 1 accessed detection
0: Not accessed
1: Accessed
Bit 0EP0F: Endpoint 0 accessed detection
0: Not accessed
1: Accessed
Rev. 1.40
225
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
UCC Register
• HT66FB540/HT66FB542
Bit
7
6
5
Name
Rctrl
R/W
R/W
R/W
R/W
POR
0
0
0
SYSCLK Fsys16MHZ
4
3
2
1
0
SUSP2
USBCKEN
—
EPS1
EPS0
R/W
R/W
—
R/W
R/W
x
0
—
x
x
“x”: unknown
Bit 7Rctrl: 7.5kΩ resistor between UDP and UBUS control bit
0: No 7.5kΩ resistor between UDP and UBUS
1: Has 7.5kΩ resistor between UDP and UBUS
Bit 6SYSCLK: Specify MCU oscillator frequency indication bit
0: 12MHz crystal oscillator or resonator, clear this bit to "0"
1: 6MHz crystal oscillator or resonator, set this bit to "1"
Bit 5Fsys16MHZ: MCU system clock source control bit
0: From OSC
1: From PLL output 16MHz
Bit 4SUSP2: Reduce power consumption in suspend mode control bit
0: In normal mode
1: In halt mode, set this bit to "1" for reducing power consumption
Bit 3USBCKEN: USB clock control bit
0: Disable
1: Enable
Rev. 1.40
Bit 2
Unimplemented, read as "0"
Bit 1~0
EPS1, EPS0: Accessing endpoint FIFO selection
00: Select endpoint 0 FIFO (control)
01: Select endpoint 1 FIFO
10: Select endpoint 2 FIFO
11: Select endpoint 3 FIFO
226
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
• HT66FB550
Bit
7
6
5
Name
Rctrl
R/W
R/W
R/W
R/W
POR
0
0
0
SYSCLK Fsys16MHZ
4
3
2
1
0
SUSP2
USBCKEN
EPS2
EPS1
EPS0
R/W
R/W
R/W
R/W
R/W
x
0
x
x
x
“x”: unknown
Bit 7Rctrl: 7.5kΩ resistor between UDP and UBUS control bit
0: No 7.5kΩ resistor between UDP and UBUS
1: Has 7.5kΩ resistor between UDP and UBUS
Bit 6SYSCLK: Specify MCU oscillator frequency indication bit
0: 12MHz crystal oscillator or resonator, clear this bit to "0"
1: 6MHz crystal oscillator or resonator, set this bit to "1"
Bit 5Fsys16MHZ: MCU system clock source control bit
0: From OSC
1: From PLL output 16MHz
Bit 4SUSP2: Reduce power consumption in suspend mode control bit
0: In normal mode
1: In halt mode, set this bit to "1" for reducing power consumption
Bit 3USBCKEN: USB clock control bit
0: Disable
1: Enable
Bit 2~0EPS2, EPS1, EPS0: Accessing endpoint FIFO selection
000: Select endpoint 0 FIFO (control)
001: Select endpoint 1 FIFO
010: Select endpoint 2 FIFO
011: Select endpoint 3 FIFO
100: Select endpoint 4 FIFO
101~111: Select endpoint 5 FIFO
Rev. 1.40
227
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
• HT66FB560
Bit
7
6
5
4
3
Name
Rctrl
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
0
0
x
0
SYSCLK Fsys16MHZ SUSP2 USBCKEN
2
1
0
EPS2
EPS1
EPS0
R/W
R/W
R/W
x
x
x
“x”: unknown
Bit 7Rctrl: 7.5kΩ resistor between UDP and UBUS control bit
0: No 7.5kΩ resistor between UDP and UBUS
1: Has 7.5kΩ resistor between UDP and UBUS
Bit 6SYSCLK: Specify MCU oscillator frequency indication bit
0: 12MHz crystal oscillator or resonator, clear this bit to "0"
1: 6MHz crystal oscillator or resonator, set this bit to "1"
Bit 5Fsys16MHZ: MCU system clock source control bit
0: From OSC
1: From PLL output 16MHz
Bit 4SUSP2: Reduce power consumption in suspend mode control bit
0: In normal mode
1: In halt mode, set this bit to "1" for reducing power consumption
Bit 3USBCKEN: USB clock control bit
0: Disable
1: Enable
Bit 2~0EPS2, EPS1, EPS0: Accessing endpoint FIFO selection
000: Select endpoint 0 FIFO (control)
001: Select endpoint 1 FIFO
010: Select endpoint 2 FIFO
011: Select endpoint 3 FIFO
100: Select endpoint 4 FIFO
101: Select endpoint 5 FIFO
110: Select endpoint 6 FIFO
111: Select endpoint 7 FIFO
AWR Register
Bit
7
6
5
4
3
2
1
0
Name
AD6
AD5
AD4
AD3
AD2
AD1
AD0
WKEN
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
x
x
x
x
x
x
x
x
“x”: unknown
Bit 7~1AD6~AD0: USB device address
Bit 0WKEN: USB remote-wake-up control bit
0: Disable
1: Enable
The AWR register contains the current address and a remote wake up function control
bit. The initial value of AWR is "00H". The address value extracted from the USB
command has not to be loaded into this register until the SETUP stage has finished.
Rev. 1.40
228
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
STLO Register
• HT66FB540/HT66FB542
Bit
7
6
5
4
3
2
1
0
Name
—
—
—
—
STLO3
STLO2
STLO1
—
R/W
—
—
—
—
R/W
R/W
R/W
—
POR
—
—
—
—
x
x
x
—
“x”: unknown
Bit 7~4
Unimplemented, read as "0"
Bit 3~1STLO3~STLO1: FIFO OUT stall endpoints indication bits
0: Not stall
1: Stall
The STLO register shows if the corresponding endpoint has worked properly or not.
As soon as endpoint improper operation occurs, the related bit in the STLO register
has to be set high. The STLO register bits will be cleared by a USB reset signal and a
setup token event.
Bit 0
Unimplemented, read as "0"
• HT66FB550
Bit
7
6
5
4
3
2
1
0
Name
—
—
STLO5
STLO4
STLO3
STLO2
STLO1
—
R/W
—
—
R/W
R/W
R/W
R/W
R/W
—
POR
—
—
x
x
x
x
x
—
“x”: unknown
Bit 7~6
Unimplemented, read as "0"
Bit 5~1STLO5~STLO1: FIFO OUT stall endpoints indication bits
0: Not stall
1: Stall
The STLO register shows if the corresponding endpoint has worked properly or not.
As soon as endpoint improper operation occurs, the related bit in the STLO register
has to be set high. The STLO register bits will be cleared by a USB reset signal and a
setup token event.
Bit 0
Unimplemented, read as "0"
• HT66FB560
Bit
7
6
5
4
3
2
1
0
Name
STLO7
STLO6
STLO5
STLO4
STLO3
STLO2
STLO1
—
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
—
POR
x
x
x
x
x
x
x
—
“x”: unknown
Bit 7~1STLO7~STLO1: FIFO OUT stall endpoints indication bits
0: Not stall
1: Stall
The STLO register shows if the corresponding endpoint has worked properly or not.
As soon as endpoint improper operation occurs, the related bit in the STLO register
has to be set high. The STLO register bits will be cleared by a USB reset signal and a
setup token event.
Bit 0
Rev. 1.40
Unimplemented, read as "0"
229
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
STLI Register
• HT66FB540/HT66FB542
Bit
7
6
5
4
3
2
1
0
Name
—
—
—
—
STLI3
STLI2
STLI1
STLI0
R/W
—
—
—
—
R/W
R/W
R/W
R/W
POR
—
—
—
—
x
x
x
x
“x”: unknown
Bit 7~4
Unimplemented, read as "0"
Bit 3~0STLI3~STLI0: FIFO IN stall endpoints indication bits
0: Not stall
1: Stall
The STLI register shows if the corresponding endpoint has worked properly or not. As
soon as endpoint improper operation occurs, the related bit in the STLI register has to
be set high. The STLI register bits will be cleared by a USB reset signal and a setup
token event.
• HT66FB550
Bit
7
6
5
4
3
2
1
0
Name
—
—
STLI5
STLI4
STLI3
STLI2
STLI1
STLI0
R/W
—
—
R/W
R/W
R/W
R/W
R/W
R/W
POR
—
—
x
x
x
x
x
x
“x”: unknown
Bit 7~6
Unimplemented, read as "0"
Bit 5~0STLI5~STLI0: FIFO IN stall endpoints indication bits
0: Not stall
1: Stall
The STLI register shows if the corresponding endpoint has worked properly or not. As
soon as endpoint improper operation occurs, the related bit in the STLI register has to
be set high. The STLI register bits will be cleared by a USB reset signal and a setup
token event.
• HT66FB560
Bit
7
6
5
4
3
2
1
0
Name
STLI7
STLI6
STLI5
STLI4
STLI3
STLI2
STLI1
STLI0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
x
x
x
x
x
x
x
x
“x”: unknown
Bit 7~0STLI7~STLI0: FIFO IN stall endpoints indication bits
0: Not stall
1: Stall
The STLI register shows if the corresponding endpoint has worked properly or not. As
soon as endpoint improper operation occurs, the related bit in the STLI register has to
be set high. The STLI register bits will be cleared by a USB reset signal and a setup
token event.
Rev. 1.40
230
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
SIES Register
Bit
7
6
5
4
3
2
1
0
Name
NMI
R/W
R/W
CRCF
—
NAK
IN
OUT
ERR
ASET
R/W
—
R
R
R/W
R/W
POR
x
R/W
x
—
x
x
x
x
x
“x”: unknown
Bit 7NMI: NAK token interrupt mask flag
0: Interrupt enable
1: Interrupt disable
If this bit set, when the device sent a NAK token to the host, an interrupt will be
disabled. Otherwise if this bit is cleared, when the device sends a NAK token to the
host, it will enter the interrupt sub-routine. This bit is used for all endpoint.
Bit 6CRCF: CRC error detection flag
0: No error
1: Error
This bit will be set to "1" when there are the following three conditions happened:
CRC error, PID error, Bit stuffing error. This bit is set by SIE and cleared by F/W.
Bit 5
Unimplemented, read as "0"
Bit 4NAK: ACK error detection flag
0: No error
1: Error
This bit will set to "1" once SIE discover there are some error condition so the SIE is
not response (NAK or ACK or DATA) for the USB token. This bit is set by SIE and
cleared by F/W.
Bit 3IN: Current USB receiving signal indicator
0 : Not IN token
1 : IN token
This bit is used to indicate the current USB receiving signal from PC host is IN token.
Bit 2OUT: USB OUT token indicator
0 : Not OUT token
1 : OUT token
This bit is used to indicate the OUT token (except the OUT zero length token) has
been received. The firmware clears this bit after the OUT data has been read. Also, this
bit will be cleared by SIE after the next valid SETUP token is received.
Bit 1ERR: FIFO accessed error indicator
0: No error
1: Error
This bit is used to indicate that some errors have occurred when the FIFO is accessed.
This bit is set by SIE and should be cleared by firmware. This bit is used for all
endpoint.
Bit 0ASET: device address updated method control bit
0: Update address immediately after an written address to the AWR register
1: Update address after the USB set address command is finished
This bit is used to configure the SIE to automatically change the device address by the
value stored in the AWR register. When this bit is set to "1" by firmware, the SIE will
update the device address by the value stored in the AWR register after the PC host has
successfully read the data from he device by an IN operation. Otherwise, when this bit
is cleared to "0", the SIE will update the device address immediately after an address
is written to the AWR register. So, in order to work properly, the firmware has to clear
this bit after a next valid SETUP token is received.
Rev. 1.40
231
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
MISC Register
• HT66FB540/HT66FB542
Bit
7
6
5
4
3
2
Name
LEN0
READY
R/W
R
R
POR
x
x
1
0
SETCMD
—
E3IDF
R/W
—
R/W
CLEAR
TX
REQUEST
R/W
R/W
x
—
x
R/W
x
x
x
“x”: unknown
Bit 7LEN0: 0-sized packet indication flag
0: Not 0-sized packet
1: 0-sized packet
This bit is used to show that the host sent a 0-sized packet to the MCU. This bit must
be cleared by a read action to the corresponding FIFO.
Bit 6READY: Desired FIFO ready indication flag
0: Not ready
1: Ready
Bit 5SETCMD: Setup command indication flag
0: Not setup command
1: Setup command
This bit is used to show that the data in the FIFO is a setup command. This bit is set by
Hardware and cleared by Firmware.
Bit 4
Unimplemented, read as "0"
Bit 3E3IDF: endpoint 3 input FIFO selection
0: Single buffer
1: Double buffer
Bit 2CLEAR: Clear FIFO function control bit
0: Disable
1: Enable
MCU requests to clear the FIFO, even if the FIFO is not ready. After clearing the
FIFO, the USB interface will send force_tx_err to tell the Host that data under-run if
the Host wants to read data.
Bit 1TX: data writing to FIFO status indication flag
0: Read data from FIFO
1: Wirte data to FIFO
To represent the direction and transition end MCU access. When set to logic 1, the
MCU desires to write data to the FIFO. After finishing, this bit must be set to logic 0
before terminating request to represent transition end. For an MCU read operation, this
bit must be set to logic 0 and set to logic 1 after finishing.
Bit 0REQUEST: Desired FIFO request status indication flag
0: No request
1: Request
After setting the status of the desired one, FIFO can be requested by setting this bit
high. After finishing, this bit must be set low.
Rev. 1.40
232
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
• HT66FB550/HT66FB560
Bit
7
6
5
4
3
2
1
0
Name
LEN0
READY
SETCMD
E4ODF
E3IDF
R/W
R
R
R/W
R/W
R/W
CLEAR
TX
REQUEST
R/W
R/W
POR
x
x
x
x
x
R/W
x
x
x
“x”: unknown
Bit 7LEN0: 0-sized packet indication flag
0: Not 0-sized packet
1: 0-sized packet
This bit is used to show that the host sent a 0-sized packet to the MCU. This bit must
be cleared by a read action to the corresponding FIFO.
Bit 6READY: Desired FIFO ready indication flag
0: Not ready
1: Ready
Bit 5SETCMD: Setup command indication flag
0: Not setup command
1: Setup command
This bit is used to show that the data in the FIFO is a setup command. This bit is set by
Hardware and cleared by Firmware.
Bit 4E4ODF: endpoint 4 output FIFO selection
0: Single buffer
1: Double buffer
Bit 3E3IDF: endpoint 3 input FIFO selection
0: Single buffer
1: Double buffer
Bit 2CLEAR: Clear FIFO function control bit
0: Disable
1: Enable
MCU requests to clear the FIFO, even if the FIFO is not ready. After clearing the
FIFO, the USB interface will send force_tx_err to tell the Host that data under-run if
the Host wants to read data.
Bit 1TX: data writing to FIFO status indication flag
0: Read data from FIFO
1: Wirte data to FIFO
To represent the direction and transition end MCU access. When set to logic 1, the
MCU desires to write data to the FIFO. After finishing, this bit must be set to logic 0
before terminating request to represent transition end. For an MCU read operation, this
bit must be set to logic 0 and set to logic 1 after finishing.
Bit 0REQUEST: Desired FIFO request status indication flag
0: No request
1: Request
After setting the status of the desired one, FIFO can be requested by setting this bit
high. After finishing, this bit must be set low.
Rev. 1.40
233
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
UFOEN Register
• HT66FB540/HT66FB542
Bit
7
6
5
4
3
2
1
0
Name
—
—
—
—
SETO3
SETO2
SETO1
DATATG
R/W
—
—
—
—
R/W
R/W
R/W
R/W
POR
—
—
—
—
0
0
0
0
Bit 7~4
Unimplemented, read as "0"
Bit 3SETO3: EP3 output FIFO control bit
0: Disable
1: Enable
Bit 2SETO2: EP2 output FIFO control bit
0: Disable
1: Enable
Bit 1SETO1: EP1 output FIFO control bit
0: Disable
1: Enable
Bit 0DATATG: DATA token toggle bit
0: Low
1: High
• HT66FB550
Bit
7
6
5
4
3
2
1
0
Name
—
—
SETO5
SETO4
SETO3
SETO2
SETO1
DATATG
R/W
—
—
R/W
R/W
R/W
R/W
R/W
R/W
POR
—
—
0
0
0
0
0
0
Bit 7~6 Unimplemented, read as "0"
Bit 5SETO5: EP5 output FIFO control bit
0: Disable
1: Enable
Bit 4SETO4: EP4 output FIFO control bit
0: Disable
1: Enable
Bit 3SETO3: EP3 output FIFO control bit
0: Disable
1: Enable
Bit 2SETO2: EP2 output FIFO control bit
0: Disable
1: Enable
Bit 1SETO1: EP1 output FIFO control bit
0: Disable
1: Enable
Bit 0DATATG: DATA token toggle bit
0: Low
1: High
Rev. 1.40
234
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
• HT66FB560
Bit
7
6
5
4
3
2
1
0
Name
SETO7
SETO6
SETO5
SETO4
SETO3
SETO2
SETO1
DATATG
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
0
0
0
0
0
0
0
Bit 7SETO7: EP7 output FIFO control bit
0: Disable
1: Enable
Bit 6SETO6: EP6 output FIFO control bit
0: Disable
1: Enable
Bit 5SETO5: EP5 output FIFO control bit
0: Disable
1: Enable
Bit 4SETO4: EP4 output FIFO control bit
0: Disable
1: Enable
Bit 3SETO3: EP3 output FIFO control bit
0: Disable
1: Enable
Bit 2SETO2: EP2 output FIFO control bit
0: Disable
1: Enable
Bit 1SETO1: EP1 output FIFO control bit
0: Disable
1: Enable
Bit 0DATATG: DATA token toggle bit
0: Low
1: High
Rev. 1.40
235
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
UFIEN Register
• HT66FB540/HT66FB542
Bit
7
6
5
4
3
2
1
0
Name
—
—
—
—
SETI3
SETI2
SETI1
FIFO_def
R/W
—
—
—
—
R/W
R/W
R/W
R/W
POR
—
—
—
—
0
0
0
0
Bit 7~4
Unimplemented, read as "0"
Bit 3SETI3: EP3 input FIFO control bit
0: Disable
1: Enable
Bit 2SETI2: EP2 input FIFO control bit
0: Disable
1: Enable
Bit 1SETI1: EP1 input FIFO control bit
0: Disable
1: Enable
Bit 0FIFO_def: FIFO configuration redefined control bit
0: Disable
1: Enable
If this bit is set to "1", the SIE should redefine the FIFO configuration. This bit will be
automatically cleared by SIE.
• HT66FB550
Bit
7
6
5
4
3
2
1
0
Name
—
—
SETI5
SETI4
SETI3
SETI2
SETI1
FIFO_def
R/W
—
—
R/W
R/W
R/W
R/W
R/W
R/W
POR
—
—
0
0
0
0
0
0
Bit 7~6
Unimplemented, read as "0"
Bit 5SETI5: EP5 input FIFO control bit
0: Disable
1: Enable
Bit 4SETI4: EP4 input FIFO control bit
0: Disable
1: Enable
Bit 3SETI3: EP3 input FIFO control bit
0: Disable
1: Enable
Bit 2SETI2: EP2 input FIFO control bit
0: Disable
1: Enable
Bit 1SETI1: EP1 input FIFO control bit
0: Disable
1: Enable
Bit 0FIFO_def: FIFO configuration redefined control bit
0: Disable
1: Enable
If this bit is set to "1", the SIE should redefine the FIFO configuration. This bit will be
automatically cleared by SIE.
Rev. 1.40
236
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
• HT66FB560
Bit
7
6
5
4
3
2
1
0
Name
SETI7
SETI6
SETI5
SETI4
SETI3
SETI2
SETI1
FIFO_def
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
0
0
0
0
0
0
0
Bit 7SETI7: EP7 input FIFO control bit
0: Disable
1: Enable
Bit 6SETI6: EP6 input FIFO control bit
0: Disable
1: Enable
Bit 5SETI5: EP5 input FIFO control bit
0: Disable
1: Enable
Bit 4SETI4: EP4 input FIFO control bit
0: Disable
1: Enable
Bit 3SETI3: EP3 input FIFO control bit
0: Disable
1: Enable
Bit 2SETI2: EP2 input FIFO control bit
0: Disable
1: Enable
Bit 1SETI1: EP1 input FIFO control bit
0: Disable
1: Enable
Bit 0FIFO_def: FIFO configuration redefined control bit
0: Disable
1: Enable
If this bit is set to "1", the SIE should redefine the FIFO configuration. This bit will be
automatically cleared by SIE.
UFC0 Register
Bit
7
6
5
4
3
2
1
0
Name
E3FS1
E3FS0
E2FS1
E2FS0
E1FS1
E1FS0
—
—
R/W
R/W
R/W
R/W
R/W
R/W
R/W
—
—
POR
0
0
0
0
0
0
—
—
Bit 7, 6E3FS1, E3SF0: endpoint 3 FIFO size selection
00: 8-byte
01: 16-byte
10: 32-byte
11: 64-byte
Bit 5, 4E2FS1, E2SF0: endpoint 2 FIFO size selection
00: 8-byte
01: 16-byte
10: 32-byte
11: 64-byte
Bit 3, 2E1FS1, E1SF0: endpoint 1 FIFO size selection
00: 8-byte
01: 16-byte
10: 32-byte
11: 64-byte
Bit 1~0
Unimplemented, read as "0"
Rev. 1.40
237
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
UFC1 Register
• HT66FB550
Bit
7
6
5
4
3
2
1
0
Name
—
—
—
—
E5FS1
E5FS0
E4FS1
E4FS0
R/W
—
—
—
—
R/W
R/W
R/W
R/W
POR
—
—
—
—
0
0
0
0
Bit 7~4
Unimplemented, read as "0"
Bit 3, 2E5FS1, E5SF0: endpoint 5 FIFO size selection
00: 8-byte
01: 16-byte
10: 32-byte
11: 64-byte
Bit 1, 0E4FS1, E4SF0: endpoint 4 FIFO size selection
00: 8-byte
01: 16-byte
10: 32-byte
11: 64-byte
• HT66FB560
Bit
7
6
5
4
3
2
1
0
Name
E7FS1
E7FS0
E6FS1
E6FS0
E5FS1
E5FS0
E4FS1
E4FS0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
0
0
0
0
0
0
0
Bit 7, 6
E7FS1, E7SF0: endpoint 7 FIFO size selection
00: 8-byte
01: 16-byte
10: 32-byte
11: 64-byte
Bit 5, 4E6FS1, E6SF0: endpoint 6 FIFO size selection
00: 8-byte
01: 16-byte
10: 32-byte
11: 64-byte
Bit 3, 2E5FS1, E5SF0: endpoint 5 FIFO size selection
00: 8-byte
01: 16-byte
10: 32-byte
11: 64-byte
Bit 1, 0E4FS1, E4SF0: endpoint 4 FIFO size selection
00: 8-byte
01: 16-byte
10: 32-byte
11: 64-byte
Rev. 1.40
238
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
USB endpoint accessing registers
• HT66FB540/HT66FB542
Bit
Register
Name
7
6
5
4
3
2
1
0
FIFO0
D7
D6
D5
D4
D3
D2
D1
D0
FIFO1
D7
D6
D5
D4
D3
D2
D1
D0
FIFO2
D7
D6
D5
D4
D3
D2
D1
D0
FIFO3
D7
D6
D5
D4
D3
D2
D1
D0
Register
Name
7
6
5
4
3
2
1
0
FIFO0
D7
D6
D5
D4
D3
D2
D1
D0
FIFO1
D7
D6
D5
D4
D3
D2
D1
D0
FIFO2
D7
D6
D5
D4
D3
D2
D1
D0
FIFO3
D7
D6
D5
D4
D3
D2
D1
D0
FIFO4
D7
D6
D5
D4
D3
D2
D1
D0
FIFO5
D7
D6
D5
D4
D3
D2
D1
D0
• HT66FB550
Bit
• HT66FB560
Rev. 1.40
Bit
Register
Name
7
6
5
4
3
2
1
0
FIFO0
D7
D6
D5
D4
D3
D2
D1
D0
FIFO1
D7
D6
D5
D4
D3
D2
D1
D0
FIFO2
D7
D6
D5
D4
D3
D2
D1
D0
FIFO3
D7
D6
D5
D4
D3
D2
D1
D0
FIFO4
D7
D6
D5
D4
D3
D2
D1
D0
FIFO5
D7
D6
D5
D4
D3
D2
D1
D0
FIFO6
D7
D6
D5
D4
D3
D2
D1
D0
FIFO7
D7
D6
D5
D4
D3
D2
D1
D0
239
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
Configuration Options
Configuration options refer to certain options within the MCU that are programmed into the devices
during the programming process. During the development process, these options are selected using
the HT-IDE software development tools. As these options are programmed into the devices using
the hardware programming tools, once they are selected they cannot be changed later using the
application program. All options must be defined for proper system function, the details of which are
shown in the table.
HT66FB542
No.
Options
Oscillator Options
1
High Speed System Oscillator Selection – fH:
1. HIRC (Default)
2. HXT
Crystal Mode Frequency Option
2
Clock Mode frequency:
1. 12MHz
2. 6MHz
I/O or VDDIO Option
3
I/O or VDDIO pin control bit:
1. VDDIO (Default)
2. I/O (PE0)
HT66FB540/HT66FB550/HT66FB560
No.
Options
Oscillator Options
1
High Speed System Oscillator Selection – fH:
1. HIRC (Default)
2. HXT
2
Low Speed System Oscillator Selection – fL:
1. LIRC (Default)
2. LXT
3
fSUB Clock Selection:
1. LIRC (Default)
2. LXT
4
Time Base Clock Selection – fTBC:
1. LIRC (Default)
2. LXT
Crystal Mode Frequency Option
5
Clock Mode frequency:
1. 12MHz
2. 6MHz
I/O or VDDIO Option
6
Rev. 1.40
I/O or VDDIO pin control bit:
1. VDDIO (Default)
2. I/O (PE0)
240
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
Application Circuits
VDD
VDD
HVDD
VDD/UBU�
0.1µF
�PI / I�C
Device
�IM
B G R
100k
10µF 0.1µF
300
RE�
1�0
0.1µF
TP0
V��
10�F
10M
6�
XT1
10�F
VBU�
DD+
V��
3�76�Hz
33
33
TP1
XT�
Q�
3904
1k
UDN
UDP
�6
TP�
47�F
47�F
Q1
3904
1k
V33O
0.1µF
AN0~1�
Cn+
CnCnO
I/O
Q3
3904
1k
Analog In�ut
Analog In�ut/ Out�ut
Key Mat�ix In�ut
Rev. 1.40
241
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
Instruction Set
Introduction
Central to the successful operation of any microcontroller is its instruction set, which is a set of
program instruction codes that directs the microcontroller to perform certain operations. In the case
of Holtek microcontroller, a comprehensive and flexible set of over 60 instructions is provided to
enable programmers to implement their application with the minimum of programming overheads.
For easier understanding of the various instruction codes, they have been subdivided into several
functional groupings.
Instruction Timing
Most instructions are implemented within one instruction cycle. The exceptions to this are branch,
call, or table read instructions where two instruction cycles are required. One instruction cycle is
equal to 4 system clock cycles, therefore in the case of an 8MHz system oscillator, most instructions
would be implemented within 0.5μs and branch or call instructions would be implemented within
1μs. Although instructions which require one more cycle to implement are generally limited to
the JMP, CALL, RET, RETI and table read instructions, it is important to realize that any other
instructions which involve manipulation of the Program Counter Low register or PCL will also take
one more cycle to implement. As instructions which change the contents of the PCL will imply a
direct jump to that new address, one more cycle will be required. Examples of such instructions
would be "CLR PCL" or "MOV PCL, A". For the case of skip instructions, it must be noted that if
the result of the comparison involves a skip operation then this will also take one more cycle, if no
skip is involved then only one cycle is required.
Moving and Transferring Data
The transfer of data within the microcontroller program is one of the most frequently used
operations. Making use of three kinds of MOV instructions, data can be transferred from registers to
the Accumulator and vice-versa as well as being able to move specific immediate data directly into
the Accumulator. One of the most important data transfer applications is to receive data from the
input ports and transfer data to the output ports.
Arithmetic Operations
The ability to perform certain arithmetic operations and data manipulation is a necessary feature of
most microcontroller applications. Within the Holtek microcontroller instruction set are a range of
add and subtract instruction mnemonics to enable the necessary arithmetic to be carried out. Care
must be taken to ensure correct handling of carry and borrow data when results exceed 255 for
addition and less than 0 for subtraction. The increment and decrement instructions INC, INCA, DEC
and DECA provide a simple means of increasing or decreasing by a value of one of the values in the
destination specified.
Rev. 1.40
242
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
Logical and Rotate Operation
The standard logical operations such as AND, OR, XOR and CPL all have their own instruction
within the Holtek microcontroller instruction set. As with the case of most instructions involving
data manipulation, data must pass through the Accumulator which may involve additional
programming steps. In all logical data operations, the zero flag may be set if the result of the
operation is zero. Another form of logical data manipulation comes from the rotate instructions such
as RR, RL, RRC and RLC which provide a simple means of rotating one bit right or left. Different
rotate instructions exist depending on program requirements. Rotate instructions are useful for serial
port programming applications where data can be rotated from an internal register into the Carry
bit from where it can be examined and the necessary serial bit set high or low. Another application
which rotate data operations are used is to implement multiplication and division calculations.
Branches and Control Transfer
Program branching takes the form of either jumps to specified locations using the JMP instruction
or to a subroutine using the CALL instruction. They differ in the sense that in the case of a
subroutine call, the program must return to the instruction immediately when the subroutine has
been carried out. This is done by placing a return instruction "RET" in the subroutine which will
cause the program to jump back to the address right after the CALL instruction. In the case of a JMP
instruction, the program simply jumps to the desired location. There is no requirement to jump back
to the original jumping off point as in the case of the CALL instruction. One special and extremely
useful set of branch instructions are the conditional branches. Here a decision is first made regarding
the condition of a certain data memory or individual bits. Depending upon the conditions, the
program will continue with the next instruction or skip over it and jump to the following instruction.
These instructions are the key to decision making and branching within the program perhaps
determined by the condition of certain input switches or by the condition of internal data bits.
Bit Operations
The ability to provide single bit operations on Data Memory is an extremely flexible feature of all
Holtek microcontrollers. This feature is especially useful for output port bit programming where
individual bits or port pins can be directly set high or low using either the "SET [m].i" or "CLR [m].
i" instructions respectively. The feature removes the need for programmers to first read the 8-bit
output port, manipulate the input data to ensure that other bits are not changed and then output the
port with the correct new data. This read-modify-write process is taken care of automatically when
these bit operation instructions are used.
Table Read Operations
Data storage is normally implemented by using registers. However, when working with large
amounts of fixed data, the volume involved often makes it inconvenient to store the fixed data in
the Data Memory. To overcome this problem, Holtek microcontrollers allow an area of Program
Memory to be setup as a table where data can be directly stored. A set of easy to use instructions
provides the means by which this fixed data can be referenced and retrieved from the Program
Memory.
Other Operations
In addition to the above functional instructions, a range of other instructions also exist such as
the "HALT" instruction for Power-down operations and instructions to control the operation of
the Watchdog Timer for reliable program operations under extreme electric or electromagnetic
environments. For their relevant operations, refer to the functional related sections.
Rev. 1.40
243
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
Instruction Set Summary
The following table depicts a summary of the instruction set categorised according to function and
can be consulted as a basic instruction reference using the following listed conventions.
Table Conventions
x: Bits immediate data
m: Data Memory address
A: Accumulator
i: 0~7 number of bits
addr: Program memory address
Mnemonic
Description
Cycles
Flag Affected
Add Data Memory to ACC
Add ACC to Data Memory
Add immediate data to ACC
Add Data Memory to ACC with Carry
Add ACC to Data memory with Carry
Subtract immediate data from the ACC
Subtract Data Memory from ACC
Subtract Data Memory from ACC with result in Data Memory
Subtract Data Memory from ACC with Carry
Subtract Data Memory from ACC with Carry, result in Data Memory
Decimal adjust ACC for Addition with result in Data Memory
1
1Note
1
1
1Note
1
1
1Note
1
1Note
1Note
Z, C, AC, OV
Z, C, AC, OV
Z, C, AC, OV
Z, C, AC, OV
Z, C, AC, OV
Z, C, AC, OV
Z, C, AC, OV
Z, C, AC, OV
Z, C, AC, OV
Z, C, AC, OV
C
1
1
1
1Note
1Note
1Note
1
1
1
1Note
1
Z
Z
Z
Z
Z
Z
Z
Z
Z
Z
Z
Increment Data Memory with result in ACC
Increment Data Memory
Decrement Data Memory with result in ACC
Decrement Data Memory
1
1Note
1
1Note
Z
Z
Z
Z
Rotate Data Memory right with result in ACC
Rotate Data Memory right
Rotate Data Memory right through Carry with result in ACC
Rotate Data Memory right through Carry
Rotate Data Memory left with result in ACC
Rotate Data Memory left
Rotate Data Memory left through Carry with result in ACC
Rotate Data Memory left through Carry
1
1Note
1
1Note
1
1Note
1
1Note
None
None
C
C
None
None
C
C
Arithmetic
ADD A,[m]
ADDM A,[m]
ADD A,x
ADC A,[m]
ADCM A,[m]
SUB A,x
SUB A,[m]
SUBM A,[m]
SBC A,[m]
SBCM A,[m]
DAA [m]
Logic Operation
AND A,[m]
OR A,[m]
XOR A,[m]
ANDM A,[m]
ORM A,[m]
XORM A,[m]
AND A,x
OR A,x
XOR A,x
CPL [m]
CPLA [m]
Logical AND Data Memory to ACC
Logical OR Data Memory to ACC
Logical XOR Data Memory to ACC
Logical AND ACC to Data Memory
Logical OR ACC to Data Memory
Logical XOR ACC to Data Memory
Logical AND immediate Data to ACC
Logical OR immediate Data to ACC
Logical XOR immediate Data to ACC
Complement Data Memory
Complement Data Memory with result in ACC
Increment & Decrement
INCA [m]
INC [m]
DECA [m]
DEC [m]
Rotate
RRA [m]
RR [m]
RRCA [m]
RRC [m]
RLA [m]
RL [m]
RLCA [m]
RLC [m]
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A/D Flash USB 8-Bit MCU with SPI
Mnemonic
Description
Cycles
Flag Affected
Move Data Memory to ACC
Move ACC to Data Memory
Move immediate data to ACC
1
1Note
1
None
None
None
Clear bit of Data Memory
Set bit of Data Memory
1Note
1Note
None
None
Jump unconditionally
Skip if Data Memory is zero
Skip if Data Memory is zero with data movement to ACC
Skip if bit i of Data Memory is zero
Skip if bit i of Data Memory is not zero
Skip if increment Data Memory is zero
Skip if decrement Data Memory is zero
Skip if increment Data Memory is zero with result in ACC
Skip if decrement Data Memory is zero with result in ACC
Subroutine call
Return from subroutine
Return from subroutine and load immediate data to ACC
Return from interrupt
2
1Note
1Note
1Note
1Note
1Note
1Note
1Note
1Note
2
2
2
2
None
None
None
None
None
None
None
None
None
None
None
None
None
Read table (specific page) to TBLH and Data Memory
Read table (current page) to TBLH and Data Memory
Read table (last page) to TBLH and Data Memory
2Note
2Note
2Note
None
None
None
No operation
Clear Data Memory
Set Data Memory
Clear Watchdog Timer
Pre-clear Watchdog Timer
Pre-clear Watchdog Timer
Swap nibbles of Data Memory
Swap nibbles of Data Memory with result in ACC
Enter power down mode
1
1Note
1Note
1
1
1
1Note
1
1
None
None
None
TO, PDF
TO, PDF
TO, PDF
None
None
TO, PDF
Data Move
MOV A,[m]
MOV [m],A
MOV A,x
Bit Operation
CLR [m].i
SET [m].i
Branch Operation
JMP addr
SZ [m]
SZA [m]
SZ [m].i
SNZ [m].i
SIZ [m]
SDZ [m]
SIZA [m]
SDZA [m]
CALL addr
RET
RET A,x
RETI
Table Read Operation
TABRD [m]
TABRDC [m]
TABRDL [m]
Miscellaneous
NOP
CLR [m]
SET [m]
CLR WDT
CLR WDT1
CLR WDT2
SWAP [m]
SWAPA [m]
HALT
Note: 1. For skip instructions, if the result of the comparison involves a skip then two cycles are required, if no
skip takes place only one cycle is required.
2. Any instruction which changes the contents of the PCL will also require 2 cycles for execution.
3. For the “CLR WDT1” and “CLR WDT2” instructions the TO and PDF flags may be affected by the
execution status. The TO and PDF flags are cleared after both “CLR WDT1” and “CLR WDT2”
instructions are consecutively executed. Otherwise the TO and PDF flags remain unchanged.
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A/D Flash USB 8-Bit MCU with SPI
Instruction Definition
ADC A,[m]
Description
Operation
Affected flag(s)
Add Data Memory to ACC with Carry
The contents of the specified Data Memory, Accumulator and the carry flag are added.
The result is stored in the Accumulator.
ACC ← ACC + [m] + C
OV, Z, AC, C
ADCM A,[m]
Description
Operation
Affected flag(s)
Add ACC to Data Memory with Carry
The contents of the specified Data Memory, Accumulator and the carry flag are added.
The result is stored in the specified Data Memory.
[m] ← ACC + [m] + C
OV, Z, AC, C
Add Data Memory to ACC
ADD A,[m]
Description
The contents of the specified Data Memory and the Accumulator are added.
The result is stored in the Accumulator.
Operation
Affected flag(s)
ACC ← ACC + [m]
OV, Z, AC, C
ADD A,x
Description
Operation
Affected flag(s)
Add immediate data to ACC
The contents of the Accumulator and the specified immediate data are added.
The result is stored in the Accumulator.
ACC ← ACC + x
OV, Z, AC, C
ADDM A,[m]
Description
Operation
Affected flag(s)
Add ACC to Data Memory
The contents of the specified Data Memory and the Accumulator are added.
The result is stored in the specified Data Memory.
[m] ← ACC + [m]
OV, Z, AC, C
AND A,[m]
Description
Operation
Affected flag(s)
Logical AND Data Memory to ACC
Data in the Accumulator and the specified Data Memory perform a bitwise logical AND
operation. The result is stored in the Accumulator.
ACC ← ACC ″AND″ [m]
Z
AND A,x
Description
Operation
Affected flag(s)
Logical AND immediate data to ACC
Data in the Accumulator and the specified immediate data perform a bit wise logical AND
operation. The result is stored in the Accumulator.
ACC ← ACC ″AND″ x
Z
ANDM A,[m]
Description
Operation
Affected flag(s)
Logical AND ACC to Data Memory
Data in the specified Data Memory and the Accumulator perform a bitwise logical AND
operation. The result is stored in the Data Memory.
[m] ← ACC ″AND″ [m]
Z
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A/D Flash USB 8-Bit MCU with SPI
CALL addr
Description
Operation
Affected flag(s)
Subroutine call
Unconditionally calls a subroutine at the specified address. The Program Counter then
increments by 1 to obtain the address of the next instruction which is then pushed onto the
stack. The specified address is then loaded and the program continues execution from this
new address. As this instruction requires an additional operation, it is a two cycle instruction.
Stack ← Program Counter + 1
Program Counter ← addr
None
CLR [m]
Description
Operation
Affected flag(s)
Clear Data Memory
Each bit of the specified Data Memory is cleared to 0.
[m] ← 00H
None
CLR [m].i
Description
Operation
Affected flag(s)
Clear bit of Data Memory
Bit i of the specified Data Memory is cleared to 0.
[m].i ← 0
None
CLR WDT
Description
Operation
Affected flag(s)
Clear Watchdog Timer
The TO, PDF flags and the WDT are all cleared.
WDT cleared
TO ← 0
PDF ← 0
TO, PDF
CLR WDT1
Description
Operation
Affected flag(s)
Pre-clear Watchdog Timer
The TO, PDF flags and the WDT are all cleared. Note that this instruction works in
conjunction with CLR WDT2 and must be executed alternately with CLR WDT2 to have
effect. Repetitively executing this instruction without alternately executing CLR WDT2 will
have no effect.
WDT cleared
TO ← 0
PDF ← 0
TO, PDF
CLR WDT2
Description
Operation
Affected flag(s)
Pre-clear Watchdog Timer
The TO, PDF flags and the WDT are all cleared. Note that this instruction works in conjunction
with CLR WDT1 and must be executed alternately with CLR WDT1 to have effect.
Repetitively executing this instruction without alternately executing CLR WDT1 will have no
effect.
WDT cleared
TO ← 0
PDF ← 0
TO, PDF
CPL [m]
Description
Operation
Affected flag(s)
Complement Data Memory
Each bit of the specified Data Memory is logically complemented (1′s complement). Bits which
previously contained a 1 are changed to 0 and vice versa.
[m] ← [m]
Z
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A/D Flash USB 8-Bit MCU with SPI
CPLA [m]
Description
Operation
Affected flag(s)
Complement Data Memory with result in ACC
Each bit of the specified Data Memory is logically complemented (1′s complement). Bits which
previously contained a 1 are changed to 0 and vice versa. The complemented result is stored in
the Accumulator and the contents of the Data Memory remain unchanged.
ACC ← [m]
Z
DAA [m]
Description
Operation
Affected flag(s)
Decimal-Adjust ACC for addition with result in Data Memory
Convert the contents of the Accumulator value to a BCD (Binary Coded Decimal) value
resulting from the previous addition of two BCD variables. If the low nibble is greater than 9
or if AC flag is set, then a value of 6 will be added to the low nibble. Otherwise the low nibble
remains unchanged. If the high nibble is greater than 9 or if the C flag is set, then a value of 6
will be added to the high nibble. Essentially, the decimal conversion is performed by adding
00H, 06H, 60H or 66H depending on the Accumulator and flag conditions. Only the C flag
may be affected by this instruction which indicates that if the original BCD sum is greater than
100, it allows multiple precision decimal addition.
[m] ← ACC + 00H or
[m] ← ACC + 06H or
[m] ← ACC + 60H or
[m] ← ACC + 66H
C
DEC [m]
Description
Operation
Affected flag(s)
Decrement Data Memory
Data in the specified Data Memory is decremented by 1.
[m] ← [m] − 1
Z
DECA [m]
Description
Operation
Affected flag(s)
Decrement Data Memory with result in ACC
Data in the specified Data Memory is decremented by 1. The result is stored in the
Accumulator. The contents of the Data Memory remain unchanged.
ACC ← [m] − 1
Z
HALT
Description
Operation
Affected flag(s)
Enter power down mode
This instruction stops the program execution and turns off the system clock. The contents of
the Data Memory and registers are retained. The WDT and prescaler are cleared. The power
down flag PDF is set and the WDT time-out flag TO is cleared.
TO ← 0
PDF ← 1
TO, PDF
INC [m]
Description
Operation
Affected flag(s)
Increment Data Memory
Data in the specified Data Memory is incremented by 1.
[m] ← [m] + 1
Z
INCA [m]
Description
Operation
Affected flag(s)
Increment Data Memory with result in ACC
Data in the specified Data Memory is incremented by 1. The result is stored in the Accumulator.
The contents of the Data Memory remain unchanged.
ACC ← [m] + 1
Z
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A/D Flash USB 8-Bit MCU with SPI
JMP addr
Description
Operation
Affected flag(s)
Jump unconditionally
The contents of the Program Counter are replaced with the specified address. Program
execution then continues from this new address. As this requires the insertion of a dummy
instruction while the new address is loaded, it is a two cycle instruction.
Program Counter ← addr
None
MOV A,[m]
Description
Operation
Affected flag(s)
Move Data Memory to ACC
The contents of the specified Data Memory are copied to the Accumulator.
ACC ← [m]
None
MOV A,x
Description
Operation
Affected flag(s)
Move immediate data to ACC
The immediate data specified is loaded into the Accumulator.
ACC ← x
None
MOV [m],A
Description
Operation
Affected flag(s)
Move ACC to Data Memory
The contents of the Accumulator are copied to the specified Data Memory.
[m] ← ACC
None
NOP
Description
Operation
Affected flag(s)
No operation
No operation is performed. Execution continues with the next instruction.
No operation
None
OR A,[m]
Description
Operation
Affected flag(s)
Logical OR Data Memory to ACC
Data in the Accumulator and the specified Data Memory perform a bitwise
logical OR operation. The result is stored in the Accumulator.
ACC ← ACC ″OR″ [m]
Z
OR A,x
Description
Operation
Affected flag(s)
Logical OR immediate data to ACC
Data in the Accumulator and the specified immediate data perform a bitwise logical OR
operation. The result is stored in the Accumulator.
ACC ← ACC ″OR″ x
Z
ORM A,[m]
Description
Operation
Affected flag(s)
Logical OR ACC to Data Memory
Data in the specified Data Memory and the Accumulator perform a bitwise logical OR
operation. The result is stored in the Data Memory.
[m] ← ACC ″OR″ [m]
Z
RET
Description
Operation
Affected flag(s)
Return from subroutine
The Program Counter is restored from the stack. Program execution continues at the restored
address.
Program Counter ← Stack
None
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A/D Flash USB 8-Bit MCU with SPI
RET A,x
Description
Operation
Affected flag(s)
Return from subroutine and load immediate data to ACC
The Program Counter is restored from the stack and the Accumulator loaded with the specified
immediate data. Program execution continues at the restored address.
Program Counter ← Stack
ACC ← x
None
RETI
Description
Operation
Affected flag(s)
Return from interrupt
The Program Counter is restored from the stack and the interrupts are re-enabled by setting the
EMI bit. EMI is the master interrupt global enable bit. If an interrupt was pending when the
RETI instruction is executed, the pending Interrupt routine will be processed before returning
to the main program.
Program Counter ← Stack
EMI ← 1
None
RL [m]
Description
Operation
Affected flag(s)
Rotate Data Memory left
The contents of the specified Data Memory are rotated left by 1 bit with bit 7 rotated into bit 0.
[m].(i+1) ← [m].i; (i=0~6)
[m].0 ← [m].7
None
RLA [m]
Description
Operation
Affected flag(s)
Rotate Data Memory left with result in ACC
The contents of the specified Data Memory are rotated left by 1 bit with bit 7 rotated into bit 0.
The rotated result is stored in the Accumulator and the contents of the Data Memory remain
unchanged.
ACC.(i+1) ← [m].i; (i=0~6)
ACC.0 ← [m].7
None
RLC [m]
Description
Operation
Affected flag(s)
Rotate Data Memory left through Carry
The contents of the specified Data Memory and the carry flag are rotated left by 1 bit. Bit 7
replaces the Carry bit and the original carry flag is rotated into bit 0.
[m].(i+1) ← [m].i; (i=0~6)
[m].0 ← C
C ← [m].7
C
RLCA [m]
Description
Operation
Affected flag(s)
Rotate Data Memory left through Carry with result in ACC
Data in the specified Data Memory and the carry flag are rotated left by 1 bit. Bit 7 replaces the
Carry bit and the original carry flag is rotated into the bit 0. The rotated result is stored in the
Accumulator and the contents of the Data Memory remain unchanged.
ACC.(i+1) ← [m].i; (i=0~6)
ACC.0 ← C
C ← [m].7
C
RR [m]
Description
Operation
Affected flag(s)
Rotate Data Memory right
The contents of the specified Data Memory are rotated right by 1 bit with bit 0 rotated into bit 7.
[m].i ← [m].(i+1); (i=0~6)
[m].7 ← [m].0
None
Rev. 1.40
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HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
RRA [m]
Description
Operation
Affected flag(s)
Rotate Data Memory right with result in ACC
Data in the specified Data Memory is rotated right by 1 bit with bit 0 rotated into bit 7.
The rotated result is stored in the Accumulator and the contents of the Data Memory remain
unchanged.
ACC.i ← [m].(i+1); (i=0~6)
ACC.7 ← [m].0
None
RRC [m]
Description
Operation
Affected flag(s)
Rotate Data Memory right through Carry
The contents of the specified Data Memory and the carry flag are rotated right by 1 bit. Bit 0
replaces the Carry bit and the original carry flag is rotated into bit 7.
[m].i ← [m].(i+1); (i=0~6)
[m].7 ← C
C ← [m].0
C
RRCA [m]
Description
Operation
Affected flag(s)
Rotate Data Memory right through Carry with result in ACC
Data in the specified Data Memory and the carry flag are rotated right by 1 bit. Bit 0 replaces
the Carry bit and the original carry flag is rotated into bit 7. The rotated result is stored in the
Accumulator and the contents of the Data Memory remain unchanged.
ACC.i ← [m].(i+1); (i=0~6)
ACC.7 ← C
C ← [m].0
C
SBC A,[m]
Description
Operation
Affected flag(s)
Subtract Data Memory from ACC with Carry
The contents of the specified Data Memory and the complement of the carry flag are
subtracted from the Accumulator. The result is stored in the Accumulator. Note that if the
result of subtraction is negative, the C flag will be cleared to 0, otherwise if the result is
positive or zero, the C flag will be set to 1.
ACC ← ACC − [m] − C
OV, Z, AC, C
SBCM A,[m]
Description
Operation
Affected flag(s)
Subtract Data Memory from ACC with Carry and result in Data Memory
The contents of the specified Data Memory and the complement of the carry flag are
subtracted from the Accumulator. The result is stored in the Data Memory. Note that if the
result of subtraction is negative, the C flag will be cleared to 0, otherwise if the result is
positive or zero, the C flag will be set to 1.
[m] ← ACC − [m] − C
OV, Z, AC, C
SDZ [m]
Description
Operation
Affected flag(s)
Skip if decrement Data Memory is 0
The contents of the specified Data Memory are first decremented by 1. If the result is 0 the
following instruction is skipped. As this requires the insertion of a dummy instruction while
the next instruction is fetched, it is a two cycle instruction. If the result is not 0 the program
proceeds with the following instruction.
[m] ← [m] − 1
Skip if [m]=0
None
Rev. 1.40
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September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
SDZA [m]
Description
Operation
Affected flag(s)
Skip if decrement Data Memory is zero with result in ACC
The contents of the specified Data Memory are first decremented by 1. If the result is 0, the
following instruction is skipped. The result is stored in the Accumulator but the specified
Data Memory contents remain unchanged. As this requires the insertion of a dummy
instruction while the next instruction is fetched, it is a two cycle instruction. If the result is not 0,
the program proceeds with the following instruction.
ACC ← [m] − 1
Skip if ACC=0
None
SET [m]
Description
Operation
Affected flag(s)
Set Data Memory
Each bit of the specified Data Memory is set to 1.
[m] ← FFH
None
SET [m].i
Description
Operation
Affected flag(s)
Set bit of Data Memory
Bit i of the specified Data Memory is set to 1.
[m].i ← 1
None
SIZ [m]
Description
Operation
Affected flag(s)
Skip if increment Data Memory is 0
The contents of the specified Data Memory are first incremented by 1. If the result is 0, the
following instruction is skipped. As this requires the insertion of a dummy instruction while
the next instruction is fetched, it is a two cycle instruction. If the result is not 0 the program
proceeds with the following instruction.
[m] ← [m] + 1
Skip if [m]=0
None
SIZA [m]
Description
Operation
Affected flag(s)
Skip if increment Data Memory is zero with result in ACC
The contents of the specified Data Memory are first incremented by 1. If the result is 0, the
following instruction is skipped. The result is stored in the Accumulator but the specified
Data Memory contents remain unchanged. As this requires the insertion of a dummy
instruction while the next instruction is fetched, it is a two cycle instruction. If the result is not
0 the program proceeds with the following instruction.
ACC ← [m] + 1
Skip if ACC=0
None
SNZ [m].i
Description
Operation
Affected flag(s)
Skip if bit i of Data Memory is not 0
If bit i of the specified Data Memory is not 0, the following instruction is skipped. As this
requires the insertion of a dummy instruction while the next instruction is fetched, it is a two
cycle instruction. If the result is 0 the program proceeds with the following instruction.
Skip if [m].i ≠ 0
None
SUB A,[m]
Description
Operation
Affected flag(s)
Subtract Data Memory from ACC
The specified Data Memory is subtracted from the contents of the Accumulator. The result is
stored in the Accumulator. Note that if the result of subtraction is negative, the C flag will be
cleared to 0, otherwise if the result is positive or zero, the C flag will be set to 1.
ACC ← ACC − [m]
OV, Z, AC, C
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A/D Flash USB 8-Bit MCU with SPI
SUBM A,[m]
Description
Operation
Affected flag(s)
Subtract Data Memory from ACC with result in Data Memory
The specified Data Memory is subtracted from the contents of the Accumulator. The result is
stored in the Data Memory. Note that if the result of subtraction is negative, the C flag will be
cleared to 0, otherwise if the result is positive or zero, the C flag will be set to 1.
[m] ← ACC − [m]
OV, Z, AC, C
SUB A,x
Description
Operation
Affected flag(s)
Subtract immediate data from ACC
The immediate data specified by the code is subtracted from the contents of the Accumulator.
The result is stored in the Accumulator. Note that if the result of subtraction is negative, the C
flag will be cleared to 0, otherwise if the result is positive or zero, the C flag will be set to 1.
ACC ← ACC − x
OV, Z, AC, C
SWAP [m]
Description
Operation
Affected flag(s)
Swap nibbles of Data Memory
The low-order and high-order nibbles of the specified Data Memory are interchanged.
[m].3~[m].0 ↔ [m].7~[m].4
None
SWAPA [m]
Description
Operation
Affected flag(s)
Swap nibbles of Data Memory with result in ACC
The low-order and high-order nibbles of the specified Data Memory are interchanged. The
result is stored in the Accumulator. The contents of the Data Memory remain unchanged.
ACC.3~ACC.0 ← [m].7~[m].4
ACC.7~ACC.4 ← [m].3~[m].0
None
SZ [m]
Description
Operation
Affected flag(s)
Skip if Data Memory is 0
If the contents of the specified Data Memory is 0, the following instruction is skipped. As this
requires the insertion of a dummy instruction while the next instruction is fetched, it is a two
cycle instruction. If the result is not 0 the program proceeds with the following instruction.
Skip if [m]=0
None
SZA [m]
Description
Operation
Affected flag(s)
Skip if Data Memory is 0 with data movement to ACC
The contents of the specified Data Memory are copied to the Accumulator. If the value is zero,
the following instruction is skipped. As this requires the insertion of a dummy instruction
while the next instruction is fetched, it is a two cycle instruction. If the result is not 0 the
program proceeds with the following instruction.
ACC ← [m]
Skip if [m]=0
None
SZ [m].i
Description
Operation
Affected flag(s)
Skip if bit i of Data Memory is 0
If bit i of the specified Data Memory is 0, the following instruction is skipped. As this requires
the insertion of a dummy instruction while the next instruction is fetched, it is a two cycle
instruction. If the result is not 0, the program proceeds with the following instruction.
Skip if [m].i=0
None
Rev. 1.40
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HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
TABRD [m]
Description
Operation
Affected flag(s)
Read table (specific page) to TBLH and Data Memory
The low byte of the program code (specific page) addressed by the table pointer pair
(TBHP and TBLP) is moved to the specified Data Memory and the high byte moved to TBLH.
[m] ← program code (low byte)
TBLH ← program code (high byte)
None
TABRDC [m]
Description
Operation
Affected flag(s)
Read table (current page) to TBLH and Data Memory
The low byte of the program code (current page) addressed by the table pointer (TBLP) is
moved to the specified Data Memory and the high byte moved to TBLH.
[m] ← program code (low byte)
TBLH ← program code (high byte)
None
TABRDL [m]
Description
Operation
Affected flag(s)
Read table (last page) to TBLH and Data Memory
The low byte of the program code (last page) addressed by the table pointer (TBLP) is moved
to the specified Data Memory and the high byte moved to TBLH.
[m] ← program code (low byte)
TBLH ← program code (high byte)
None
XOR A,[m]
Description
Operation
Affected flag(s)
Logical XOR Data Memory to ACC
Data in the Accumulator and the specified Data Memory perform a bitwise logical XOR
operation. The result is stored in the Accumulator.
ACC ← ACC ″XOR″ [m]
Z
XORM A,[m]
Description
Operation
Affected flag(s)
Logical XOR ACC to Data Memory
Data in the specified Data Memory and the Accumulator perform a bitwise logical XOR
operation. The result is stored in the Data Memory.
[m] ← ACC ″XOR″ [m]
Z
XOR A,x
Description
Operation
Affected flag(s)
Logical XOR immediate data to ACC
Data in the Accumulator and the specified immediate data perform a bitwise logical XOR
operation. The result is stored in the Accumulator.
ACC ← ACC ″XOR″ x
Z
Rev. 1.40
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HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
Package Information
Note that the package information provided here is for consultation purposes only. As this
information may be updated at regular intervals users are reminded to consult the Holtek website for
the latest version of the package information.
Additional supplementary information with regard to packaging is listed below. Click on the relevant
section to be transferred to the relevant website page.
• Further Package Information (include Outline Dimensions, Product Tape and Reel Specifications)
• Packing Meterials Information
• Carton information
Rev. 1.40
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A/D Flash USB 8-Bit MCU with SPI
24-pin SSOP (150mil) Outline Dimensions
Symbol
Dimensions in inch
Min.
Nom.
Max.
A
—
0.236 BSC
—
B
—
0.154 BSC
—
C
0.008
—
0.012
C’
—
0.341 BSC
—
D
—
—
0.069
E
—
0.025 BSC
—
F
0.004
—
0.010
G
0.016
—
0.050
H
0.004
—
0.010
α
0°
—
8°
Symbol
Rev. 1.40
Dimensions in mm
Min.
Nom.
Max.
A
—
6.000 BSC
—
B
—
3.900 BSC
—
C
0.20
—
0.30
C’
—
8.660 BSC
—
D
—
—
1.75
E
—
0.635 BSC
—
F
0.10
—
0.25
G
0.41
—
1.27
H
0.10
—
0.25
α
0°
—
8°
256
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
28-pin SSOP(150mil) Outline Dimensions
Symbol
Dimensions in inch
Min.
Nom.
Max.
A
—
0.236 BSC
—
B
—
0.154 BSC
—
C
0.008
—
0.012
C’
—
0.390 BSC
—
D
—
—
0.069
E
—
0.025 BSC
—
F
0.004
—
0.010
G
0.016
—
0.050
H
0.004
—
0.010
α
0°
—
8°
Symbol
Rev. 1.40
Dimensions in mm
Min.
Nom.
Max.
A
—
6.000 BSC
—
B
—
3.900 BSC
—
C
0.20
—
0.30
C’
—
9.900 BSC
—
D
—
—
1.75
E
—
0.635 BSC
—
F
0.10
—
0.25
G
0.41
—
1.27
H
0.10
—
0.25
α
0°
—
8°
257
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
SAW Type 40-pin (6mm × 6mm for 0.75mm) QFN Outline Dimensions
Symbol
Min.
Nom.
Max.
A
0.028
0.030
0.031
A1
0.000
0.001
0.002
A3
—
0.008 REF
—
b
0.007
0.010
0.012
D
0.232
0.236
0.240
E
0.232
0.236
0.240
e
—
0.020 BSC
—
D2
0.173
0.177
0.181
E2
0.173
0.177
0.181
L
0.014
0.016
0.018
K
0.008
—
—
Symbol
Rev. 1.40
Dimensions in inch
Dimensions in mm
Min.
Nom.
Max.
A
0.700
0.750
0.800
A1
0.000
0.020
0.050
A3
—
0.203 REF
—
b
0.180
0.250
0.300
D
5.900
6.000
6.100
E
5.900
6.000
6.100
e
—
0.500 BSC
—
D2
4.40
4.50
4.60
E2
4.40
4.50
4.60
L
0.35
0.40
0.45
K
0.20
—
—
258
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
48-pin LQFP (7mm × 7mm) Outline Dimensions
Symbol
Dimensions in inch
Min.
Nom.
Max.
A
—
0.354 BSC
—
B
—
0.276 BSC
—
C
—
0.354 BSC
—
D
—
0.276 BSC
—
E
—
0.020 BSC
—
F
0.007
0.009
0.011
G
0.053
0.055
0.057
H
—
—
0.063
I
0.002
—
0.006
J
0.018
0.024
0.030
K
0.004
—
0.008
α
0°
―
7°
Symbol
Rev. 1.40
Dimensions in mm
Min.
Nom.
Max.
A
—
9.00 BSC
—
B
—
7.00 BSC
—
C
—
9.00 BSC
—
D
—
7.00 BSC
—
E
—
0.50 BSC
—
F
0.17
0.22
0.27
G
1.35
1.40
1.45
H
—
—
1.60
I
0.05
—
0.15
J
0.45
0.60
0.75
K
0.09
—
0.20
α
0°
―
7°
259
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
64-pin LQFP (7mm × 7mm) Outline Dimensions
Symbol
Min.
Nom.
Max.
A
—
0.354 BSC
—
B
—
0.276 BSC
—
C
—
0.354 BSC
—
D
—
0.276 BSC
—
E
—
0.016 BSC
—
F
0.005
0.007
0.009
G
0.053
0.055
0.057
H
—
—
0.063
I
0.002
—
0.006
J
0.018
0.024
0.030
K
0.004
—
0.008
α
0°
—
7°
Symbol
Rev. 1.40
Dimensions in inch
Dimensions in mm
Min.
Nom.
Max.
A
—
9.00 BSC
—
B
—
7.00 BSC
—
C
—
9.00 BSC
—
D
—
7.00 BSC
—
E
—
0.40 BSC
—
F
0.13
0.18
0.23
G
1.35
1.40
1.45
H
—
—
1.60
I
0.05
—
0.15
J
0.45
0.60
0.75
K
0.09
—
0.20
α
0°
—
7°
260
September 18, 2015
HT66FB540/HT66FB542/HT66FB550/HT66FB560
A/D Flash USB 8-Bit MCU with SPI
Copyright© 2015 by HOLTEK SEMICONDUCTOR INC.
The information appearing in this Data Sheet is believed to be accurate at the time
of publication. However, Holtek assumes no responsibility arising from the use of
the specifications described. The applications mentioned herein are used solely
for the purpose of illustration and Holtek makes no warranty or representation that
such applications will be suitable without further modification, nor recommends
the use of its products for application that may present a risk to human life due to
malfunction or otherwise. Holtek's products are not authorized for use as critical
components in life support devices or systems. Holtek reserves the right to alter
its products without prior notification. For the most up-to-date information, please
visit our web site at http://www.holtek.com.
Rev. 1.40
261
September 18, 2015