HT68FB5x0

I/O Flash USB 8-Bit MCU with SPI
HT68FB540/HT68FB550/HT68FB560
Revision: V1.30
Date: �����������������
December 11, 2013
HT68FB540/HT68FB550/HT68FB560
I/O Flash USB 8-Bit MCU with SPI
Table of Contents
Features............................................................................................................. 6
CPU Features.......................................................................................................................... 6
Peripheral Features.................................................................................................................. 6
General Description.......................................................................................... 7
Selection Table.................................................................................................. 8
Block Diagram................................................................................................... 8
Pin Assignment................................................................................................. 9
Pin Description............................................................................................... 12
Absolute Maximum Ratings........................................................................... 18
D.C. Characteristics........................................................................................ 18
A.C. Characteristics........................................................................................ 20
LVD & LVR Electrical Characteristics........................................................... 21
Power on Reset (AC+DC) Electrical Characteristics................................... 21
System Architecture....................................................................................... 22
Clocking and Pipelining.......................................................................................................... 22
Program Counter.................................................................................................................... 23
Stack...................................................................................................................................... 24
Arithmetic and Logic Unit – ALU............................................................................................ 24
Flash Program Memory.................................................................................. 25
Structure................................................................................................................................. 25
Special Vectors...................................................................................................................... 25
Look-up Table......................................................................................................................... 26
Table Program Example......................................................................................................... 26
In System Programming – ISP............................................................................................... 27
Flash Memory Read/Write Page Size.................................................................................... 27
ISP Bootloader....................................................................................................................... 29
Flash Program Memory Registers......................................................................................... 29
In Application Program – IAP................................................................................................ 33
In Circuit Programming – ICP................................................................................................ 37
On-Chip Debug Support – OCDS.......................................................................................... 37
RAM Data Memory.......................................................................................... 38
Structure................................................................................................................................. 38
Special Function Register Description......................................................... 42
Indirect Addressing Registers – IAR0, IAR1.......................................................................... 42
Memory Pointers – MP0, MP1............................................................................................... 42
Bank Pointer – BP.................................................................................................................. 43
Accumulator – ACC................................................................................................................ 44
Program Counter Low Register – PCL................................................................................... 44
Rev. 1.30
2
December 11, 2013
HT68FB540/HT68FB550/HT68FB560
I/O Flash USB 8-Bit MCU with SPI
Look-up Table Registers – TBLP, TBHP, TBLH...................................................................... 44
Status Register – STATUS..................................................................................................... 45
Oscillator......................................................................................................... 46
Oscillator Overview................................................................................................................ 46
System Clock Configurations................................................................................................. 46
External Crystal Oscillator – HXT........................................................................................... 47
Internal PLL Frequency Generator......................................................................................... 48
Internal RC Oscillator – HIRC................................................................................................ 50
Internal 32kHz Oscillator – LIRC............................................................................................ 50
Supplementary Internal Clocks.............................................................................................. 50
Operating Modes and System Clocks.......................................................... 50
System Clocks....................................................................................................................... 51
System Operation Modes....................................................................................................... 51
Control Register..................................................................................................................... 53
Fast Wake-up......................................................................................................................... 54
Operating Mode Switching and Wake-up............................................................................... 55
Standby Current Considerations............................................................................................ 58
Wake-up................................................................................................................................. 59
Programming Considerations................................................................................................. 59
Watchdog Timer.............................................................................................. 60
Watchdog Timer Clock Source............................................................................................... 60
Watchdog Timer Control Register.......................................................................................... 60
Watchdog Timer Operation.................................................................................................... 61
Reset and Initialisation................................................................................... 62
Reset Overview...................................................................................................................... 62
Reset Functions..................................................................................................................... 63
Reset Initial Conditions.......................................................................................................... 67
Input/Output Ports.......................................................................................... 77
Pull-high Resistors................................................................................................................. 79
Port Wake-up......................................................................................................................... 81
Port A Wake-up Polarity Control Register ............................................................................. 82
I/O Port Control Registers...................................................................................................... 83
Port A , Port D Power Source Control Registers.................................................................... 84
I/O Pin Structures................................................................................................................... 86
Programming Considerations................................................................................................. 86
Timer Modules – TM....................................................................................... 87
Introduction............................................................................................................................ 87
TM Operation......................................................................................................................... 87
TM Clock Source.................................................................................................................... 88
TM Interrupts.......................................................................................................................... 88
TM External Pins.................................................................................................................... 88
TM Input/Output Pin Control Registers.................................................................................. 89
Programming Considerations................................................................................................. 92
Compact Type TM.................................................................................................................. 93
Rev. 1.30
3
December 11, 2013
HT68FB540/HT68FB550/HT68FB560
I/O Flash USB 8-Bit MCU with SPI
Compact TM Operation.......................................................................................................... 94
Compact Type TM Register Description................................................................................ 94
Compact Type TM Operating Modes..................................................................................... 98
Compare Match Output Mode................................................................................................ 98
Timer/Counter Mode............................................................................................................ 100
PWM Output Mode............................................................................................................... 101
Standard Type TM – STM............................................................................. 104
Standard TM Operation........................................................................................................ 104
Standard Type TM Register Description.............................................................................. 105
Standard Type TM Operating Modes....................................................................................112
Compare Output Mode..........................................................................................................112
Timer/Counter Mode.............................................................................................................113
Timer/Counter Mode.............................................................................................................114
PWM Output Mode................................................................................................................114
Single Pulse Mode................................................................................................................117
Capture Input Mode..............................................................................................................119
Serial Interface Module – SIM...................................................................... 121
SPI Interface........................................................................................................................ 121
SPI Interface Operation........................................................................................................ 121
SPI Registers....................................................................................................................... 122
SPI Communication............................................................................................................. 125
SPI Bus Enable/Disable....................................................................................................... 127
SPI Operation....................................................................................................................... 128
Error Detection..................................................................................................................... 129
I2C Interface......................................................................................................................... 129
I2C Bus Communication....................................................................................................... 134
I2C Bus Start Signal.............................................................................................................. 135
I2C Bus Slave Address......................................................................................................... 135
I2C Bus Read/Write Signal................................................................................................... 136
I2C Bus Slave Address Acknowledge Signal........................................................................ 136
I2C Bus Data and Acknowledge Signal................................................................................ 136
I2C Time Out Function.......................................................................................................... 138
Serial Interface – SPIA.................................................................................. 138
SPIA Interface Operation..................................................................................................... 139
SPIA Registers..................................................................................................................... 140
SPIA Communication................................................................................... 142
SPIA Bus Enable/Disable..................................................................................................... 144
SPIA Operation.................................................................................................................... 145
Error Detection..................................................................................................................... 146
Peripheral Clock Output............................................................................... 147
Peripheral Clock Operation.................................................................................................. 147
Rev. 1.30
4
December 11, 2013
HT68FB540/HT68FB550/HT68FB560
I/O Flash USB 8-Bit MCU with SPI
Interrupts....................................................................................................... 148
Interrupt Registers................................................................................................................ 148
Interrupt Operation............................................................................................................... 152
External Interrupt.................................................................................................................. 153
USB Interrupt....................................................................................................................... 154
Serial Interface Module Interrupts – SIM Interrupt............................................................... 154
Serial Peripheral Interface Interrupt – SPIA Interrupt........................................................... 154
LVD Interrupt........................................................................................................................ 154
Multi-function Interrupt......................................................................................................... 154
TM Interrupts........................................................................................................................ 155
Interrupt Wake-up Function.................................................................................................. 155
Programming Considerations............................................................................................... 155
Low Voltage Detector – LVD........................................................................ 156
LVD Register........................................................................................................................ 156
LVD Operation...................................................................................................................... 157
USB Interface................................................................................................ 157
Power Plane......................................................................................................................... 158
USB Suspend Wake-Up Remote Wake-Up......................................................................... 158
USB Interface Operation...................................................................................................... 159
USB Interface Registers....................................................................................................... 160
Configuration Options.................................................................................. 177
Application Circuits...................................................................................... 178
Instruction Set............................................................................................... 179
Introduction.......................................................................................................................... 179
Instruction Timing................................................................................................................. 179
Moving and Transferring Data.............................................................................................. 179
Arithmetic Operations........................................................................................................... 179
Logical and Rotate Operations............................................................................................. 180
Branches and Control Transfer............................................................................................ 180
Bit Operations...................................................................................................................... 180
Table Read Operations........................................................................................................ 180
Other Operations.................................................................................................................. 180
Instruction Set Summary...................................................................................................... 181
Instruction Definition.................................................................................... 183
Package Information.................................................................................... 192
20-pin SSOP (150mil) Outline Dimensions.......................................................................... 193
24-pin SSOP (150mil) Outline Dimensions.......................................................................... 194
28-pin SSOP (150mil) Outline Dimensions.......................................................................... 195
SAW Type 20-pin (4mm×4mm) QFN Outline Dimensions................................................... 196
48-pin LQFP (7mm×7mm) Outline Dimensions................................................................... 197
Rev. 1.30
5
December 11, 2013
HT68FB540/HT68FB550/HT68FB560
I/O 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
• Three oscillators:
♦♦
External Crystal - HXT
♦♦
Internal RC - HIRC
♦♦
Internal 32kHz RC - LIRC
• Multi-mode operation: NORMAL, SLOW, IDLE and SLEEP
• 2 Compact type 10-bit Timer Module - CTM
• 1 Standard type 10-bit Timer Module - STM
• 1 Standard type 16-bit Timer Module - STM
• All instructions executed in one or two instruction cycles
• Table read instructions
• 62 powerful instructions
• Up to 12-level subroutine nesting
• Bit manipulation instruction
Peripheral Features
• Flash Program Memory: 4K×16~16K×16
• RAM Data Memory: 256×8~768×8
• 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 1.5K ohm pull-up resistor
• Internal 12MHz RC OSC with 0.25% accuracy for all USB modes
• Watchdog Timer function
• Up to 37 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
• Serial Interface Modules with Dual SPI and I2C interfaces
• Single Serial SPI interface
• Low voltage reset function
Rev. 1.30
6
December 11, 2013
HT68FB540/HT68FB550/HT68FB560
I/O Flash USB 8-Bit MCU with SPI
• Low voltage detect function
• Wide range of available package types
• Flash program memory can be re-programmed up to 1,000,000 times
• Flash program memory data retenton > 10 years
• Support In System Programming function - ISP
General Description
The HT68FB540, HT68FB550 and HT68FB560 are Flash Memory I/O with USB type 8-bit high
performance RISC architecture microcontrollers, designed for applications that interface directly
to which require an USB interface. Offering users the convenience of Flash Memory multiprogramming features, these devices also include a wide range of functions and features. Other
memory includes an area of RAM Data Memory.
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 three 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 along with many other features ensure that the
devices will find specific excellent use in a wide range of application possibilities such as motor
driving, industrial control, consumer products, subsystem controllers, etc.
The 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. 1.30
7
December 11, 2013
HT68FB540/HT68FB550/HT68FB560
I/O 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, stack capacity and package types. The following table summarises the main
features of each device.
Part No.
VDD
HT68FB540
2.2V~
5.5V
Program
Data
Memory Memory
Ext.
Interrupt
17
2
Timer
Module
SIM
(SPI/I2C)
SPI
Stack
Package
√
√
8
20QFN
20/24SSOP
√
√
8
24/28SSOP
48LQFP
√
√
12
24/28SSOP
48LQFP
10-bit CTM×2
4K×16
256×8
10-bit STM×1
16-bit STM×1
10-bit CTM×2
2.2V~
HT68FB550
5.5V
8K×16
2.2V~
5.5V
16K×16
HT68FB560
I/O
512×8
25
10-bit STM×1
2
16-bit STM×1
10-bit CTM×2
768×8
37
10-bit STM×1
2
16-bit STM×1
Block Diagram
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December 11, 2013
HT68FB540/HT68FB550/HT68FB560
I/O Flash USB 8-Bit MCU with SPI
Pin Assignment
HT68FB540
PA5/SDIA/TP1_0
PA6/TCK0/SCKA
PA7/INT0/SCSA
PA4/SDOA/TP0_0
UDN/GPIO0
UDP/GPIO1
V33O
UBUS/PE1/VDD
HVDD
PE�
�0 19 18 17 16
15
1
14
�
HT68FB540
13
3
20 QFN-A
1�
4
11
5
6 7 8 9 10
PA7/INT0/SCSA
PA4/SDOA/TP0_0
UDN/GPIO0
UDP/GPIO1
V33O
UBUS/PE1/VDD
HVDD
PE�
PA3/TCK�
PA�/TP3_1/OSC�
PA1/TP�_1/OSC1
PA0/TCK1/OCDSDA
PE0/VDDIO
PB�/TCK3/SCK
PB1/SDI/SCL
PB0/SDO/SDA
RES/OCDSCK
VSS
VSS
RES/OCDSCK
1
�
3
4
5
6
7
8
9
10
�0
19
18
17
16
15
14
13
1�
11
PA6/TCK0/SCKA
PA5/SDIA/TP1_0
PA3/TCK�
PA�/TP3_1/OSC�
PA1/TP�_1/OSC1
PA0/TCK1/OCDSDA
PE0/VDDIO
PB�/TCK3/SCK
PB1/SDI/SCL
PB0/SDO/SDA
HT68FB540
20 SSOP-A
PA4/SDOA/TP0_0
1
�4
PA7/INT0/SCSA
PE0/VDDIO
�
�3
PA6/TCK0/SCKA
UDN/GPIO0
3
��
UDP/GPIO1
V33O
4
�1
PA5/SDIA/TP1_0
PA3/TCK�
5
�0
PA�/TP3_1/OSC�
UBUS/PE1/VDD
6
19
PA1/TP�_1/OSC1
HVDD
7
18
PA0/TCK1/OCDSDA
PE�
8
17
PB5/PCK/TP3_0
VSS
RES/OCDSCK
9
16
PB4/TP0_1
10
15
PB3/SCS/TP1_1
11
14
PB�/TCK3/SCK
1�
13
PB1/SDI/SCL
PB0/SDO/SDA
PB6/INT1/TP�_0
HT68FB540
24 SSOP-A
Rev. 1.30
9
December 11, 2013
HT68FB540/HT68FB550/HT68FB560
I/O Flash USB 8-Bit MCU with SPI
HT68FB550
PA6/TCK0/SCKA
1
�4
PA5/SDIA/TP1_0
PA7/INT0/SCSA
�
�3
PA4/SDOA/TP0_0
UDN/GPIO0
3
��
UDP/GPIO1
V33O
4
5
UBUS/PE1/VDD
PA6/TCK0/SCKA
PA7/INT0/SCSA
1
�8
�
�7
PA4/SDOA/TP0_0
PA3/TCK�
UDN/GPIO0
3
�6
PA3/TCK�
�1
PA�/TP3_1/OSC�
�5
PA�/TP3_1/OSC�
PA1/TP�_1/OSC1
UDP/GPIO1
V33O
4
�0
5
�4
PA1/TP�_1/OSC1
6
19
PA0/TCK1/OCDSDA
UBUS/PE1/VDD
6
�3
HVDD
7
18
HVDD
7
��
PA0/TCK1/OCDSDA
PE0/VDDIO
PE�
8
17
PE0/VDDIO
PB6/INT1/TP�_0
PE�
8
�1
PD3
VSS
9
16
PB5/PCK/TP3_0
9
�0
15
PB4/TP0_1
PD�
RES/OCDSCK
10
VSS
10
19
14
PB3/SCS/TP1_1
11
1�
13
PB�/TCK3/SCK
PD0
18
PB6/INT1/TP�_0
PB0/SDO/SDA
PB1/SDI/SCL
11
RES/OCDSCK
PD1
PB0/SDO/SDA
1�
17
13
16
PB3/SCS/TP1_1
PB1/SDI/SCL
14
15
PB�/TCK3/SCK
HT68FB550
24 SSOP-A
PA5/SDIA/TP1_0
PB5/PCK/TP3_0
PB4/TP0_1
HT68FB550
28 SSOP-A
PA3/TCK�
PA4/SDOA/TP0_0
PA5/SDIA/TP1_0
PA6/TCK0/SCKA
PA7/INT0/SCSA
NC
NC
NC
NC
NC
NC
NC
NC
UDN/GPIO0
UDP/GPIO1
V33O
UBUS/PE1/VDD
HVDD
PE�
VSS
RES/OCDSCK
NC
NC
NC
48 47 46 45 44 43 4� 41 40 39 38 37
36
1
35
�
34
3
33
4
5
3�
31
6
HT68FB550
7
30
48 LQFP-A
�9
8
�8
9
�7
10
�6
11
�5
1�
13 14 1516 17 18 19 �0 �1 �� �3 �4
PA�/TP3_1/OSC�
PA1/TP�_1/OSC1
PA0/TCK1/OCDSDA
PE0/VDDIO
PD7
PD6
PD5
PD4
PD3
PD�
NC
PB6/INT1/TP�_0
PB5/PCK/TP3_0
NC
NC
NC
NC
PB4/TP0_1
PB3/SCS/TP1_1
PB�/TCK3/SCK
PB1/SDI/SCL
PB0/SDO/SDA
PD1
PD0
Rev. 1.30
10
December 11, 2013
HT68FB540/HT68FB550/HT68FB560
I/O Flash USB 8-Bit MCU with SPI
HT68FB560
PA6/TCK0/SCKA
1
�4
PA5/SDIA/TP1_0
PA6/TCK0/SCKA
1
�8
PA5/SDIA/TP1_0
PA7/INT0/SCSA
�
�3
PA4/SDOA/TP0_0
PA7/INT0/SCSA
�
�7
PA4/SDOA/TP0_0
UDN/GPIO0
3
��
PA3/TCK�
UDN/GPIO0
3
�6
PA3/TCK�
UDP/GPIO1
V33O
4
�1
PA�/TP3_1/OSC�
4
�5
PA�/TP3_1/OSC�
5
�0
PA1/TP�_1/OSC1
UDP/GPIO1
V33O
5
�4
PA1/TP�_1/OSC1
UBUS/PE1/VDD
6
19
6
�3
7
18
PA0/TCK1/OCDSDA
PE0/VDDIO
UBUS/PE1/VDD
HVDD
HVDD
7
��
PA0/TCK1/OCDSDA
PE0/VDDIO
PE�
8
17
PB6/INT1/TP�_0
PE�
8
�1
PD3
VSS
9
16
PB5/PCK/TP3_0
VSS
9
�0
PD�
RES/OCDSCK
10
15
PB4/TP0_1
RES/OCDSCK
10
19
PB0/SDO/SDA
PB1/SDI/SCL
11
14
PB3/SCS/TP1_1
PD0
11
18
PB6/INT1/TP�_0
1�
13
PB�/TCK3/SCK
PD1
PB0/SDO/SDA
1�
17
13
16
PB3/SCS/TP1_1
PB1/SDI/SCL
14
15
PB�/TCK3/SCK
HT68FB560
24 SSOP-A
PB5/PCK/TP3_0
PB4/TP0_1
HT68FB560
28 SSOP-A
PA3/TCK�
PA4/SDOA/TP0_0
PA5/SDIA/TP1_0
PA6/TCK0/SCKA
PA7/INT0/SCSA
PC0
PC1
PC�
PC3
PC4
PC5
PC6
PC7
UDN/GPIO0
UDP/GPIO1
V33O
UBUS/PE1/VDD
HVDD
PE�
VSS
RES/OCDSCK
PE3
PE4
PE5
48 47 46 45 44 43 4� 41 40 39 38 37
36
1
35
�
34
3
4
33
5
3�
31
6
HT68FB560
7
30
48 LQFP-A
�9
8
�8
9
�7
10
�6
11
�5
1�
13 14 1516 17 18 19 �0 �1 �� �3 �4
PA�/TP3_1/OSC�
PA1/TP�_1/OSC1
PA0/TCK1/OCDSDA
PE0/VDDIO
PD7
PD6
PD5
PD4
PD3
PD�
PB7
PB6/INT1/TP�_0
PB5/PCK/TP3_0
NC
NC
NC
NC
PB4/TP0_1
PB3/SCS/TP1_1
PB�/TCK3/SCK
PB1/SDI/SCL
PB0/SDO/SDA
PD1
PD0
Rev. 1.30
11
December 11, 2013
HT68FB540/HT68FB550/HT68FB560
I/O 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 function
such as the 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.
HT68FB540
Pin Name
PA0/TCK1/
OCDSDA
PA1/TP2_1/
OSC1
PA2/TP3_1/
OSC2
PA3/TCK2
PA4/SDOA/
TP0_0
PA5/SDIA/
TP1_0
PA6/TCK0/
SCKA
PA7/INT0/SCSA
PB0/SDO/SDA
PB1/SDI/SCL
Rev. 1.30
Function
OPT
I/T
PA0
PAPU
PAWU
ST
TCK1
—
ST
O/T
Description
CMOS General purpose I/O. Register enabled pull-up and wake-up.
—
TM1 input
OCDSDA
—
ST
Debug Data I/O in On-Chip Debug Support mode for OCDS
CMOS
EV only
PA1
PAPU
PAWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up.
TP2_1
TMPC1
ST
CMOS TM2 I/O
OSC1
—
HXT
PA2
PAPU
PAWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up.
TP3_1
TMPC1
ST
CMOS TM3 I/O
OSC2
—
—
PA3
PAPU
PAWU
ST
TCK2
—
ST
PA4
PAPU
PAWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up.
—
HXT
HXT pin
HXT pin
CMOS General purpose I/O. Register enabled pull-up and wake-up.
—
TM2 input
SDOA
—
—
CMOS SPIA Data output
TP0_0
TMPC0
ST
CMOS TM0 I/O
PA5
PAPU
PAWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up.
SDIA
—
ST
TP1_0
TMPC0
ST
CMOS TM1 I/O
—
PA6
PAPU
PAWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up.
TCK0
—
ST
SCKA
—
ST
NMOS SPIA Serial Clock
PA7
PAPU
PAWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up.
INT0
—
ST
SCSA
—
ST
CMOS SPIA Slave select
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
PB1
PXPU
PXWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up.
SDI
—
ST
SCL
—
ST
—
—
—
SPIA Data input
TM0 input
External interrupt 0
SPI Data input
NMOS I2C Clock
12
December 11, 2013
HT68FB540/HT68FB550/HT68FB560
I/O Flash USB 8-Bit MCU with SPI
Pin Name
PB2/TCK3/SCK
PB3/SCS/TP1_1
PB4/TP0_1
PB5/PCK/TP3_0
PB6/INT1/TP2_0
PE0/VDDIO
VDD/PE1/UBUS
PE2
RES/OCDSCK
UDN/GPIO0
UDP/GPIO1
Function
OPT
I/T
PB2
PXPU
PXWU
ST
TCK3
TMPC1
ST
SCK
—
ST
CMOS SPI Serial Clock
PB3
PXPU
PXWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up.
Description
CMOS General purpose I/O. Register enabled pull-up and wake-up.
—
TM3 input
SCS
—
ST
CMOS SPI Slave select
TP1_1
TMPC0
ST
CMOS TM1 I/O
PB4
PXPU
PXWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up.
TP0_1
TMPC0
ST
CMOS TM0 I/O
PB5
PXPU
PXWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up.
PCK
—
—
CMOS Peripheral output clock
TP3_0
TMPC1
ST
CMOS TM3 I/O
PB6
PXPU
PXWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up.
INT1
—
ST
TP2_0
TMPC1
ST
CMOS TM2 I/O
PE0
PXPU
PXWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up.
VDDIO
—
PWR
—
PA external power input
VDD
—
PWR
—
Power supply
—
External interrupt 1
PE1
—
ST
—
General purpose I/O, Input pin
UBUS
—
PWR
—
USB SIE VDD
PE2
PXPU
PXWU
ST
RES
—
ST
OCDSCK
—
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up.
—
Reset input
—
Debug clock input in On-Chip Debug Support mode for OCDS
EV only
UDN
—
ST
CMOS USB UDN line
GPIO0
—
ST
CMOS General purpose I/O
UDP
—
ST
CMOS USB UDP line
CMOS General purpose I/O
GPIO1
—
ST
VSS
—
PWR
V33O
V33O
—
—
HVDD
HVDD
—
PWR
VSS
O/T
—
Ground
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
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. 1.30
13
December 11, 2013
HT68FB540/HT68FB550/HT68FB560
I/O Flash USB 8-Bit MCU with SPI
HT68FB550
Pin Name
PA0/TCK1/
OCDSDA
PA1/TP2_1/
OSC1
PA2/TP3_1/
OSC2
PA3/TCK2
PA4/SDOA/
TP0_0
PA5/SDIA/
TP1_0
PA6/TCK0/
SCKA
PA7/INT0/
SCSA
PB0/SDO/
SDA
PB1/SDI/SCL
PB2/TCK3/
SCK
Rev. 1.30
Function
OPT
I/T
PA0
PAPU
PAWU
ST
TCK1
—
ST
O/T
Description
CMOS General purpose I/O. Register enabled pull-up and wake-up.
—
TM1 input
OCDSDA
—
ST
Debug Data I/O in On-Chip Debug Support mode for OCDS
CMOS
EV only
PA1
PAPU
PAWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up
TP2_1
TMPC1
ST
CMOS TM2 I/O
OSC1
—
HXT
PA2
PAPU
PAWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up.
TP3_1
TMPC1
ST
CMOS TM3 I/O
OSC2
—
—
PA3
PAPU
PAWU
ST
TCK2
—
ST
PA4
PAPU
PAWU
ST
—
HXT
HXT pin
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.
SDOA
—
—
CMOS SPIA Data output
TP0_0
TMPC0
ST
CMOS TM0 I/O
PA5
PAPU
PAWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up.
SDIA
—
ST
TP1_0
TMPC0
ST
CMOS TM1 I/O
PA6
PAPU
PAWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up.
TCK0
—
ST
SCKA
—
ST
NMOS SPIA Serial Clock
PA7
PAPU
PAWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up.
—
—
—
SPIA Data input
TM0 input
INT0
—
ST
SCSA
—
ST
CMOS SPIA Slave select
External interrupt 0
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
PB1
PXPU
PXWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up.
SDI
—
ST
SCL
—
ST
NMOS I2C Clock
PB2
PXPU
PXWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up.
TCK3
TMPC1
ST
SCK
—
ST
—
—
SPI Data input
TM3 input
CMOS SPI Serial Clock
14
December 11, 2013
HT68FB540/HT68FB550/HT68FB560
I/O Flash USB 8-Bit MCU with SPI
Pin Name
PB3/SCS/
TP1_1
PB4/TP0_1
PB5/PCK/
TP3_0
PB6/ INT1/
TP2_0
PD0~PD7
PE0/VDDIO
VDD/PE1/
UBUS
PE2
RES/OCDSCK
UDN/GPIO0
UDP/GPIO1
Function
OPT
I/T
PB3
PXPU
PXWU
O/T
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up.
SCS
—
ST
CMOS SPI Slave select
TP1_1
TMPC0
ST
CMOS TM1 I/O
PB4
PXPU
PXWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up.
TP0_1
TMPC0
ST
CMOS TM0 I/O
PB5
PXPU
PXWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up.
PCK
—
—
CMOS Peripheral output clock.
TP3_0
TMPC1
ST
CMOS TM3 I/O
PB6
PXPU
PXWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up.
INT1
—
ST
TP2_0
TMPC1
ST
CMOS TM2 I/O
PD0~PD7
PXPU
PXWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up.
PE0
PXPU
PXWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up.
VDDIO
—
PWR
—
PA, PD4~PD7 external power input.
VDD
—
PWR
—
Power supply
PE1
—
ST
—
General purpose I/O, Input pin
UBUS
—
PWR
—
USB SIE VDD
PE2
PXPU
PXWU
ST
RES
—
ST
OCDSCK
—
ST
UDN
—
ST
—
Description
External interrupt 1
CMOS General purpose I/O. Register enabled pull-up and wake-up.
—
Reset input
—
Debug clock input in On-Chip Debug Support mode for OCDS
EV only
CMOS USB UDN line.
GPIO0
—
ST
CMOS General purpose I/O
UDP
—
ST
CMOS USB UDP line
CMOS General purpose I/O
GPIO1
—
ST
VSS
VSS
—
PWR
—
V33O
V33O
—
—
PWR
HVDD
HVDD
—
PWR
—
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
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. 1.30
15
December 11, 2013
HT68FB540/HT68FB550/HT68FB560
I/O Flash USB 8-Bit MCU with SPI
HT68FB560
Pin Name
PA0/TCK1/
OCDSDA
PA1/TP2_1/
OSC1
PA2/TP3_1/
OSC2
PA3/TCK2
PA4/SDOA/
TP0_0
PA5/SDIA/
TP1_0
PA6/TCK0/
SCKA
PA7/INT0/
SCSA
PB0/SDO/SDA
PB1/SDI/SCL
PB2/TCK3/
SCK
Rev. 1.30
Function
OPT
I/T
PA0
PAPU
PAWU
ST
TCK1
—
ST
O/T
Description
CMOS General purpose I/O. Register enabled pull-up and wake-up.
—
TM1 input
OCDSDA
—
ST
Debug Data I/O in On-Chip Debug Support mode for OCDS
CMOS
EV only
PA1
PAPU
PAWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up.
TP2_1
TMPC1
ST
CMOS TM2 I/O
OSC1
—
HXT
PA2
PAPU
PAWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up.
TP3_1
TMPC1
ST
CMOS TM3 I/O
OSC2
—
—
PA3
PAPU
PAWU
ST
TCK2
—
ST
PA4
PAPU
PAWU
ST
—
HXT
HXT pin
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.
SDOA
—
—
CMOS SPIA Data output
TP0_0
TMPC0
ST
CMOS TM0 I/O
PA5
PAPU
PAWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up.
SDIA
—
ST
TP1_0
TMPC0
ST
CMOS TM1 I/O
PA6
PAPU
PAWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up.
TCK0
—
ST
SCKA
—
ST
NMOS SPIA Serial Clock
PA7
PAPU
PAWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up.
—
—
—
SPIA Data input
TM0 input
INT0
—
ST
SCSA
—
ST
CMOS SPIA Slave select
External interrupt 0
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
PB1
PXPU
PXWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up.
SDI
—
ST
SCL
—
ST
NMOS I2C Clock
PB2
PXPU
PXWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up.
TCK3
TMPC1
ST
SCK
—
ST
—
—
SPI Data input
TM3 input
CMOS SPI Serial Clock
16
December 11, 2013
HT68FB540/HT68FB550/HT68FB560
I/O Flash USB 8-Bit MCU with SPI
Pin Name
PB3/SCS/
TP1_1
PB4/TP0_1
PB5/PCK/
TP3_0
PB6/INT1/
TP2_0
Function
OPT
I/T
PB3
PXPU
PXWU
O/T
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up.
SCS
—
ST
CMOS SPI Slave select
TP1_1
TMPC0
ST
CMOS TM1 I/O
PB4
PXPU
PXWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up.
TP0_1
TMPC0
ST
CMOS TM0 I/O
PB5
PXPU
PXWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up.
PCK
—
—
CMOS Peripheral output clock
TP3_0
TMPC1
ST
CMOS TM3 I/O
PB6
PXPU
PXWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up.
INT1
—
ST
TP2_0
TMPC1
ST
CMOS TM2 I/O
PB7
PXPU
PXWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up.
PC0~PC7
PC0~PC7
PXPU
PXWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up.
PD0~PD7
PD0~PD7
PXPU
PXWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up.
PE0
PXPU
PXWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up.
PB7
PE0/VDDIO
VDD/PE1/
UBUS
PE2~PE5
RES/OCDSCK
UDN/GPIO0
—
Description
External interrupt 1
VDDIO
—
PWR
—
PA, PD4~PD7 external power input
VDD
—
PWR
—
Power supply.
PE1
—
ST
—
General purpose I/O, Input pin
UBUS
—
PWR
—
USB SIE VDD
PE2~PE5
PXPU
PXWU
ST
RES
—
ST
—
Reset input
OCDSCK
—
ST
—
Debug clock input in On-Chip Debug Support mode for OCDS
EV only
CMOS General purpose I/O. Register enabled pull-up and wake-up.
UDN
—
ST
CMOS USB UDN line
GPIO0
—
ST
CMOS General purpose I/O.
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
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. 1.30
17
December 11, 2013
HT68FB540/HT68FB550/HT68FB560
I/O Flash USB 8-Bit MCU with SPI
Absolute Maximum Ratings
Supply Voltage ......................... VSS-0.3V to VSS +6.0V
Storage Temperature ........................... -50°C to 125°C
Input Voltage ............................VSS-0.3V to VDD +0.3V
Operating Temperature ......................... -40°C to 85°C
IOL Total..............................................................150mA
IOH Total............................................................ -100mA
Total Power Dissipation������������������������������������500mV
Note: These are stress ratings only. Stresses exceeding the range specified under "Absolute Maximum Ratings"
may cause substantial damage to the device. Functional operation of this device at other conditions beyond
those listed in the specification is not implied and prolonged exposure to extreme conditions may affect
device reliability.
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.
Max.
Unit
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,
WDT enable
—
0.8
1.5
mA
—
1.8
4.0
mA
No load, fH=6MHz,
WDT enable
—
1.0
2.0
mA
—
2.5
5.0
mA
No load, fH=8MHz,
WDT enable
—
1.3
3.0
mA
—
3.0
5.5
mA
—
2.0
4.0
mA
—
4.0
7.0
mA
—
2.0
4.0
mA
—
4.0
7.0
mA
No load, ADC off, fLIRC=32kHz,
WDT enable, LVR enable
—
40
80
μA
—
70
150
μA
No load, fH=12MHz, WDT
enable, USB enable, PLL on,
V33O on
—
5.5
10.0
mA
—
5V
3V
IDD1
Operating Current
(Crystal OSC, fSYS=fH, fS=fLIRC)
5V
3V
5V
3V
5V
Operating Current
(HIRC OSC, fSYS=fH, fS=fLIRC)
3V
IDD3
Operating Current
(LIRC OSC, fSYS=fL=fLIRC, fS=fLIRC)
3V
IDD4
Operating Current
(HIRC OSC, fSYS=fH, fS=fLIRC)
3V
IDD2
IDD5
Rev. 1.30
Operating Current
(Crystal OSC, fSYS=fH, fS=fLIRC)
Conditions
VDD
5V
5V
5V
No load, fH=12MHz,
WDT enable
No load, fH=12MHz,
WDT enable
—
11
16
mA
5V
No load, fH=6MHz, WDT enable,
USB enable, PLL on, V33O on
—
10
15
mA
5V
No load, fH=12MHz, WDT
enable, USB enable, PLL on,
V33O on
—
11
16
mA
5V
No load, fH=16MHz, WDT
enable, USB enable, PLL on,
V33O on
—
12
17
mA
18
December 11, 2013
HT68FB540/HT68FB550/HT68FB560
I/O Flash USB 8-Bit MCU with SPI
Symbol
Parameter
Test Conditions
Min.
Typ.
Max.
Unit
—
0.8
1.5
mA
—
1.5
3.0
mA
No load, system HALT,
WDT enable, oscillator off
(FSYSON=0)
—
1.5
3.0
μA
—
3.0
6.0
μA
No load, system HALT,
WDT enable
—
1.5
3.0
μA
—
3.0
6.0
μA
No load, system HALT,
WDT disable
—
0.1
1.0
μA
—
0.3
2.0
μA
Conditions
VDD
ISTB1
Standby Current (Idle 1)
(Crystal or HIRC OSC,
fSYS=fH, fS=fLIRC)
ISTB2
Standby Current (Idle 0)
(Crystal or HIRC OSC,
fSYS=off, fS=fLIRC)
3V
ISTB3
Standby Current (Idle 0)
(LIRC OSC, fSYS=off, fS=fLIRC)
3V
ISTB4
Standby Current (Sleep 0)
(Crystal or HIRC OSC,
fSYS=off, fS=fLIRC)
3V
ISTB5
Standby Current (Sleep 0)
(Crystal or HIRC OSC,
fSYS=off, fS=fLIRC)
—
No load, system HALT, WDT
disable, LVR enable and
LVDEN=1
—
60
90
μA
ISUS1
Suspend Current (Sleep 0)
(Crystal or HIRC OSC,
fSYS=off, fS=fLIRC)
5V
No load, system HALT, 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=fLIRC)
5V
No load, system HALT, 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)
—
IOL
I/O Port Sink Current
IOH
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
Rev. 1.30
3V
5V
5V
5V
5V
No load, system HALT,
WDT enable, oscillator on
(FSYSON=1)
0.9VDD
—
VDD
V
3V
—
VOL=0.1VDD
4
8
—
mA
5V
VOL=0.1VDD
10
20
—
mA
3V
VOH=0.9VDD
-2
-4
—
mA
5V
VOH=0.9VDD
-5
-10
—
mA
5V
IV33O=70mA
3.0
3.3
3.6
V
3.3V
—
-5%
1.5
+5%
kΩ
3V
—
20
60
100
kΩ
5V
—
10
30
50
kΩ
0.5
1
1.5
MΩ
5V
SUSP2=1, RUBUS=0
19
December 11, 2013
HT68FB540/HT68FB550/HT68FB560
I/O Flash USB 8-Bit MCU with SPI
A.C. Characteristics
Ta= 25°C
Symbol
Parameter
VDD
Condition
2.2~5.5V
2.2~5.5V
fSYS1
System Clock (Crystal OSC)
2.2~5.5V
—
2.7~5.5V
System Clock (HIRC OSC)
System Clock (32K RC)
Timer I/P Frequency (TMR)
tTIMER
tRES
tINT
VBG Turn on Stable Time
TCKn Input Pin Minimum Pulse
Width
External Reset Minimum Low
Pulse Width
Interrupt Minimum Pulse Width
System Start-up Timer Period
(Wake-up from HALT, fSYS off
at HALT state, Slow Mode →
Normal Mode)
tSST
tRSTD
Rev. 1.30
MHz
2
—
6
MHz
2
—
8
MHz
2
—
12
MHz
—
16
MHz
+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
-0.25%
12
Ta= 25°C
-10%
32
+10%
2.2~5.5V Ta= -40°C to 85°C
-50%
32
+60%
kHz
2
—
8
MHz
2
—
12
MHz
2
—
16
MHz
5V
2.7~5.5V
—
4.5~5.5V
tBGS
Unit
4
12
2.2~5.5V
fTIMER
Max.
—
2
3.3~5.5V USB mode
fLIRC
Typ.
2
-3%
4.5~5.5V
2.2~5.5V Non-USB mode, Ta=25°C
fSYS2
Min.
+0.25% MHz
kHz
—
—
10
—
—
ms
—
—
0.3
—
—
μs
—
—
10
—
—
μs
—
—
10
—
—
μs
—
fSYS=HXT (Slow Mode → Normal Mode (HXT))
1024
—
—
tSYS
—
fSYS=HXT (Wake-up from
HALT, fSYS off at HALT state)
1024
—
—
tSYS
—
fSYS=HIRC
1024
—
—
tSYS
—
fSYS=LIRC
2
—
—
tSYS
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
20
December 11, 2013
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I/O Flash USB 8-Bit MCU with SPI
LVD & LVR Electrical Characteristics
Ta= 25°C
Symbol
Test Conditions
Parameter
VLVR2
Min.
LVR Enable, 2.1V option
VLVR1
VLVR3
Conditions
VDD
Low Voltage Reset Voltage
—
LVR Enable, 2.55V option
LVR Enable, 3.15V option
Typ.
Max.
2.1
-5%
×Typ.
2.55
3.15
Unit
V
+5%
×Typ.
V
V
VLVR4
LVR Enable, 3.8V 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
3V
ILVD
Additional Power Consumption
if LVD/LVR is Used
5V
tLVR
Low Voltage Width to Reset
—
tLVD
Low Voltage Width to Interrupt
—
tSRESET
Software Reset Width to Reset
—
tLVDS
LVDO Stable Time
—
—
30
45
μA
—
60
90
μA
—
120
240
480
μs
—
20
45
90
μs
—
45
90
120
μs
15
—
—
μs
LVD disable → LVD enable
(LVR enable)
For LVR enable, LVD off → on
Power on Reset (AC+DC) Electrical Characteristics
Ta= 25°C
Symbol
VDD
Condition
Min.
Typ.
Max.
Unit
VPOR
VDD Start Voltage to ensure
Power-on Reset
—
—
—
—
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
Parameter
Rev. 1.30
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I/O 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 control system with maximum reliability and flexibility. This makes the device
suitable for low-cost, high-volume production for controller applications.
Clocking and Pipelining
The main system clock, derived from either a HXT, HIRC or LIRC oscillator is subdivided into
four internally generated non-overlapping clocks, T1~T4. 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. 1.30
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HT68FB540/HT68FB550/HT68FB560
I/O 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 nonconsecutive Program Memory address. 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
Program Counter
Program Counter High Byte
HT68FB540
PC11~PC8
HT68FB550
PC12~PC8
HT68FB560
PC13~PC8
PCL Register
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. 1.30
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I/O 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 the device 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
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
B o tto m
C o u n te r
P ro g ra m
M e m o ry
S ta c k L e v e l 3
o f S ta c k
S ta c k L e v e l N
Device
Stack Levels
HT68FB540/HT68FB550
8
HT68FB560
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. 1.30
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I/O 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 this device
series the Program Memory is 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, this Flash device offers 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 4Kx16 bits to 16Kx16 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
HT68FB540
4K × 16
0
HT68FB550
8K × 16
0
HT68FB560
16K × 16
0,1
The HT68FB560 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 the device 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 2 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
1 6 b its
1 6 b its
0 0 0 0 H
0 0 0 4 H
1 F F F H
2 0 0 0 H
B a n k 1
3 F F F H
Program Memory Structure
Rev. 1.30
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I/O 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.
T B L P R e g is te r
A d d re s s
T B H 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 HT68FB550. 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. 1.30
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I/O Flash USB 8-Bit MCU with SPI
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 device.
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 the 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.
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.
Rev. 1.30
Device
Page Size (Words)
Write Buffer (Words)
HT68FB540 (4K×16)
32
32
HT68FB550 (8K×16)
32
32
HT68FB560 (16K×16)
64
64
27
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HT68FB540/HT68FB550/HT68FB560
I/O Flash USB 8-Bit MCU with SPI
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 H/L 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. First 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. 1.30
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I/O 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 accopanying diagram illustrates the Flash
memory structure with Holtek Bootloader software.
HT68FB540
HT68FB550
Bootloade�
0D00H
0DFFH
Bootloade�
0000H
0000H
HT68FB560
Bootloade�
0000H
Last Page
Bank 0
1D00H
1DFFH
Last Page
1FFFH
Bank 1
3D00H
3DFFH
Last Page
Flash Program Memory Registers
There are two address registers, four 16-bit data registers and two control register. The control
register is located in Bank1 and the other registers are located in Bank0. 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. 1.30
29
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I/O Flash USB 8-Bit MCU with SPI
Program Memory Register List
• HT68FB540
Bit
Name
FARL
7
6
5
4
3
2
1
0
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
FRCR
—
—
—
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
• HT68FB550
Bit
Name
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
FRCR
—
—
—
FSWRST
—
—
—
CLWB
7
6
5
4
3
2
1
0
D7
D6
D5
D4
D3
D2
D1
D0
D8
• HT68FB560
Name
FARL
Rev. 1.30
Bit
FARH
—
—
D13
D12
D11
D10
D9
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
FRCR
—
—
—
FSWRST
—
—
—-
CLWB
30
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HT68FB540/HT68FB550/HT68FB560
I/O 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
D7~D0: Flash Program Memory address
Flash Program Memory address bit 7~bit 0
FARH Register
• HT68FB540
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
D11~D8: Flash Program Memory address
Flash Program Memory address bit 11~bit 8
• HT68FB550
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
D12~D8: Flash Program Memory address
Flash Program Memory address bit 12~bit 8
• HT68FB560
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
Bit 7~6 Reserved, cannot be used
Bit 5~0
Rev. 1.30
D13~D8: Flash Program Memory address
Flash Program Memory address bit 13~bit 8
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FCR Register
Rev. 1.30
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 7
CFWEN: 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 6~4 FMOD2~FMOD0: Flash Program memory, Configuration option 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 3
BWT: 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 2
FWT: 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 1
FRDEN: 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 0
FRD: 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 registers can not be set to "1" at the same time with
a single instruction.
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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 4 FSWRST: control bit
Must be to 0
Bit 3~1 "—": unimplemented, read as "0"
Bit 0 CLWB: Flash Program memory Write buffer clear control bit
0: do not initiate clear Write Buffer or clear process
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 Program – IAP
Offering users the convenience of Flash Memory multi-programming features, the HT68FB5x0
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 CAN, 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".
• The device 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.
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Set FWEN
Fmod2~0=110 : Set FWEN bit
BWT=1,Hardware set a counter
Wrtie the following pattern to Flash Data register
FD1L= 00h , FD1H = 04h
FD2L=0dh , FD2H = 09h
FD3L=C3h , FD3H = 40h
No
Is counter
overflow?
BWT=0?
Yes
Is pattern is
correct ?
No
Yes
CFWEN=1
.
Set FWEN bit success
CFWEN=0
Set FWEN bit fail
END
Rev. 1.30
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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
FAH=xxh, FAL=xxh
Fmod2~0=001
FWT=1
No
FWT=0 ?
Yes
Write
Fmod2~0=000
Write data to Write Buffer
[(ROM ≤ 8K 1~32 Words data) or
(ROM > 8K 1~64 Words data)]:
Flash address register: FAH=xxh, FAL=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 ROM Procedure
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Read Flash
Fmod2~0=011
FRDEN=1
flash address register:
FAH=xxh, FAL=xxh
FRD=1
No
FRD=0 ?
Yes
Read value:
FD0L=xxh, FD0H=xxh
No
Read Finish ?
Yes
FRDEN=0
Clear CFWEN bit
END
Read Flash
Procedure option Procedure
Read Flash Program
orProgram
Configuration
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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.
On-Chip Debug Support – OCDS
There is an EV chip named HT68VB540/HT68VB550/HT68VB560 which is used to emulate the
HT68FB540/HT68FB550/HT68FB560 device. The HT68VB540/HT68VB550/HT68VB560 device
also provides the “On-Chip Debug” function to debug the HT68FB540/HT68FB550/HT68FB560
device during development process. The two devices, HT68FB540/HT68FB550/HT68FB560 and
HT68VB540/HT68VB550/HT68VB560, are almost functional compatible except the “On-Chip
Debug” function. Users can use the HT68VB540/HT68VB550/HT68VB560 device to emulate the
HT68FB540/HT68FB550/HT68FB560 device behaviors by connecting the OCDSDA and OCDSCK
Rev. 1.30
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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 HT68VB540/
HT68VB550/HT68VB560 EV chip for debugging, the corresponding pin functions shared with the
OCDSDA and OCDSCK pins in the HT68FB540/HT68FB550/HT68FB560 device will have no effect
in the HT68VB540/HT68VB550/HT68VB560 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
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
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 device. 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
HT68FB540
256×8
0: 80H~FFH
1: 80H~FFH
512×8
0: 80H~FFH
1: 80H~FFH
2: 80H~FFH
3: 80H~FFH
768×8
0: 80H~FFH
1: 80H~FFH
2: 80H~FFH
3: 80H~FFH
4: 80H~FFH
5: 80H~FFH
HT68FB550
HT68FB560
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
the device 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.
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I/O Flash USB 8-Bit MCU with SPI


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Rev. 1.30
39
December 11, 2013
HT68FB540/HT68FB550/HT68FB560
I/O Flash USB 8-Bit MCU with SPI


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Rev. 1.30
40
December 11, 2013
HT68FB540/HT68FB550/HT68FB560
I/O Flash USB 8-Bit MCU with SPI


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Rev. 1.30
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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
adres1db ?
adres2db ?
adres3db ?
adres4db ?
block db ?
code .section at 0 code
org 00h
start:
mov a,04h; setup size of block
mov block,a
mov a,offset adres1 ; Accumulator loaded with first RAM address
mov mp0,a ; setup memory pointer with first RAM address
loop:
clr IAR0 ; clear the data at address defined by MP0
inc mp0; increment memory pointer
sdz block ; check if last memory location has been cleared
jmp loop
continue:
The important point to note here is that in the example shown above, no reference is made to specific
RAM addresses.
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Bank Pointer – BP
Depending upon which device is 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 Banks 0 ~ 5.
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
7
6
5
4
3
2
1
0
HT68FB540
—
—
—
—
—
—
—
DMBP0
HT68FB550
—
—
—
—
—
—
DMBP1
DMBP0
HT68FB560
—
—
PMBP0
—
—
DMBP2
DMBP1
DMBP0
BP Registers List
BP Register
• HT68FB540
Bit
7
6
5
4
3
2
1
0
Name
—
—
—
—
—
—
—
DMBP0
R/W
R
R
R
R
R
R
R
R/W
POR
0
0
0
0
0
0
0
0
Bit 7~1
"—": unimplemented, read as "0"
Bit 0
DMBP0: Select Data Memory Banks
0: bank 0
1: bank 1
• HT68FB550
Rev. 1.30
Bit
7
6
5
4
3
2
1
0
Name
—
—
—
—
—
—
DMBP1
DMBP0
R/W
R
R
R
R
R
R
R/W
R/W
POR
0
0
0
0
0
0
0
0
Bit 7~2
"—": unimplemented, read as "0"
Bit 1~0
DMBP1, DMBP0: Select Data Memory Banks
00: bank 0
01: bank 1
10: bank 2
11: bank 3
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• HT68FB560
Bit
7
6
5
4
3
2
1
0
Name
—
—
PMBP0
—
—
DMBP2
DMBP1
DMBP0
R/W
R
R
R/W
R
R
R/W
R/W
R/W
POR
0
0
0
0
0
0
0
0
Bit 7~6
"—": unimplemented, read as "0"
Bit 5
PMBP0: 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 2~0
DMBP2 ~ 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: unimplemented
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.
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 pointer and indicates 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.
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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.
STATUS Register
Bit
7
6
5
4
3
2
1
0
Name
—
—
TO
PDF
OV
Z
AC
C
R/W
R
R
R
R
R/W
R/W
R/W
R/W
POR
0
0
0
0
x
x
x
x
"x" unknown
Rev. 1.30
Bit 7~6
"—": unimplemented, read as "0"
Bit 5
TO: Watchdog Time-Out flag
0: after power up or executing the "CLR WDT" or "HALT" instruction
1: a watchdog time-out occurred.
Bit 4
PDF: Power down flag
0: after power up or executing the "CLR WDT" instruction
1: by executing the "HALT" instruction
Bit 3
OV: 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 2
Z: 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
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Bit 1
AC: 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 0
C: 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.
Oscillator
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 Interrupt. 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. The high speed oscillator, HXT or HIRC,
option is selected through the configuration option. 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 oscillator. With the capability of dynamically switching
between fast and slow system clock, the device has the flexibility to optimize the performance/
power ratio, a feature especially important in power sensitive portable applications.
Type
Name
Freq.
Pins
External Crystal
HXT
6MHz or 12MHz
OSC1/OSC2
Internal High Speed RC
HIRC
12MHz
—
Internal Low Speed RC
LIRC
32kHz
—
Oscillator Types
Note: For USB applications, HXT must be connected an 6MHz or 12MHz crystal.
System Clock Configurations
There are several oscillator sources, two high speed oscillators and one low speed oscillator.
The high speed system clocks are sourced from the external crystal/ ceramic oscillator, the PLL
frequency generator and the internal 12MHz RC oscillator. The low speed oscillator is the internal
32kHz RC oscillator. 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 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. 1.30
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I/O Flash USB 8-Bit MCU with SPI
USBCKEN �it
48MHz
Config.Option
Sele�ts
6 o� 1�MHz XTAL
÷�
HIRC
OSC
HOSC
16MHz
HOSC
HXT
OSC
High speed
Os�illato�
To USBCK
�i��uits
6MHz
PLL
1�MHz
SYSCLK
Bit
SYSCLK
�it
fH/�
fH/4
fH/8
fH/16
fH/3�
PLL �it
HOSC
PLL �it
P�es�ale�
PLL �lo�k
6MHz
Configu�ation
Option
fH
FSYS16MHz
�it
USBCKEN
�it
fH/64
fH
fL
LIRC
OSC
fSYS
HCLK �it
CKS0-CKS� �it
fL
fSUB
Fast Wake-Up f�o�
SLEEP o� IDLE �ode
Cont�ol (fo� HXT only)
WDT
System Clock Configurations
External Crystal Oscillator – HXT
The External Crystal System Oscillator is one of the high frequency oscillator.
     Crystal/Ceramic System 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.
Rev. 1.30
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I/O Flash USB 8-Bit MCU with SPI
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 either 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 7
Bit 6 Bit 5 Bit 4~3 Rev. 1.30
CLK_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.
USBdis: USB SIE control bit
USB related control bit, described elsewhere
RUBUS: UBUS pin pull low resistor
USB related control bit, described elsewhere
"—": 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"
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I/O Flash USB 8-Bit MCU with SPI
UCC Register
• HT68FB540
Bit
7
Name
Rctrl
R/W
R/W
R/W
R/W
POR
0
0
0
Bit 7 Bit 6 Bit 5
Bit 4
Bit 3
Bit 2 Bit 1~0 6
5
SYSCLK Fsys16MHZ
4
3
2
1
0
SUSP2
USBCKEN
—
EPS1
EPS0
R/W
R/W
R
R/W
R/W
0
0
0
0
0
Rctrl: 7.5kΩ resistor between UDP and UBUS control bit
USB related control bit, described elsewhere
SYSCLK: System clock frequency select bit
0: 12MHz 1: 6MHz
Note: If a 6 MHz crystal or resonator is used for the MCU, this bit should be set to "1". If a 12 MHz 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".
Fsys16MHZ: PLL 16MHz output control bit
0: HXT
1: PLL 16MHz
SUSP2: Reduce power consumption in suspend mode control bit
USB related control bit, described elsewhere
USBCKEN: USB clock control bit
0: disable
1: enable
"—": unimplemented, read as "0"
EPS1, EPS0: Accessing endpoint FIFO selection
USB related control bit, described elsewhere
USC Register
Rev. 1.30
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
0
0
0
0
SELUSB RESUME
Bit 7
URD: USB reset signal control function definition
USB related control bit, described elsewhere
Bit 6
SELPS2: the chip works under PS2 mode indicator bit
USB related control bit, described elsewhere
Bit 5
PLL: PLL control bit
0: Turn-on PLL
1: Turn-off PLL
Bit 4
SELUSB: the chip works under USB mode indicator bit
USB related control bit, described elsewhere
Bit 3 RESUME: USB resume indication bit
USB related control bit, described elsewhere
Bit 2 URST: USB reset indication bit
USB related control bit, described elsewhere
Bit 1 RMWK: USB remote wake-up command
USB related control bit, described elsewhere
Bit 0 SUSP: USB suspend indication USB related control bit, described elsewhere
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I/O Flash USB 8-Bit MCU with SPI
The following table illustrates the PLL output frequency selected by the related control bits.
PLL
USBCKEN
Fsys16MHZ
0
0
0
HOSC (HXT or HIRC)
fH
0
0
1
fPLL – 16MHz
0
1
0
fPLL – 6MHz or 12MHz, 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"
High Frequency System Clock fH Selection Table
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 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 PA1 and PA2 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.
Internal 32kHz Oscillator – LIRC
The Internal 32kHz System Oscillator 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
degrees, the fixed oscillation frequency of 32kHz will have a tolerance within 10%.
Supplementary Internal Clocks
The low speed oscillator, in addition to providing a system clock source is also used to provide a
clock source, namely fSUB, to the Watchdog Timer Interrupt.
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.
Rev. 1.30
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I/O Flash USB 8-Bit MCU with SPI
System Clocks
The device has 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 or HIRC oscillator, selected via a configuration
option. The low speed system clock source can be provided by internal clock fL, sourced by the
LIRC oscillator. The other choice, which is a divided version of the high speed system oscillator has
a range of fH/2~fH/64. The fSUB clock is used as the clock source for the Watchdog timer.
USBCKEN �it
48MHz
Config.Option
Sele�ts
6 o� 1�MHz XTAL
÷�
HIRC
OSC
High speed
Os�illato�
HOSC
16MHz
HOSC
HXT
OSC
To USBCK
�i��uits
6MHz
PLL
1�MHz
fH
6MHz
Configu�ation
Option
SYSCLK
Bit
SYSCLK
�it
fH/�
fH/4
fH/8
fH/16
fH/3�
PLL �it
HOSC
PLL �it
P�es�ale�
PLL �lo�k
FSYS16MHz
�it
USBCKEN
�it
fH/64
fH
fL
LIRC
OSC
fSYS
HCLK �it
CKS0-CKS� �it
fL
fSUB
WDT
Fast Wake-Up f�o�
SLEEP o� IDLE �ode
Cont�ol (fo� HXT only)
System Clock Configurations
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.
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
Rev. 1.30
Description
CPU
fSYS
fSUB
NORMAL Mode
On
fH ~ fH/64
On
SLOW Mode
On
fL
On
IDLE0 Mode
Off
Off
On
On
IDLE1 Mode
Off
On
SLEEP0 Mode
Off
Off
Off
SLEEP1 Mode
Off
Off
On
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I/O Flash USB 8-Bit MCU with SPI
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 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 is provided by 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.
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.
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.
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 fL 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.
Rev. 1.30
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I/O Flash USB 8-Bit MCU with SPI
Control Register
A single register, SMOD is used for overall control of the internal clocks within the device.
SMOD Register
Rev. 1.30
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 7~5 CKS2~CKS0: The system clock selection when HLCLK is "0".
000: fL ( fLIRC)
001: fL (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 the LIRC, a divided version of the
high speed system oscillator can also be chosen as the system clock source.
Bit 4
FSTEN: Fast Wake-up Control (only for HXT )
0: disable
1: enable
This is the Fast Wake-up Control bit which determines if the fL clock source is initially
used after the device wakes up. When the bit is high, the fL clock source can be used as
a temporary system clock to provide a faster wake up time as the fL clock is available.
Bit 3
LTO: 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 1~2 clock cycles if the LIRC oscillator is used.
Bit 2
HTO: 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 the device is
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
device 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 1
IDLEN: 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 the
device 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 the device will enter the SLEEP Mode when a HALT
instruction is executed.
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I/O Flash USB 8-Bit MCU with SPI
Bit 0
HLCLK: 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.
Fast Wake-up
To minimise power consumption the device can enter the SLEEP or IDLE0 Mode, where the system
clock source to the device will be stopped. However when the device is 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 fL, namely the 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 fL, the Fast Wake-up function is only available in the SLEEP1 and IDLE0 modes. When
the device is woken up from the SLEEP0 mode, the Fast Wake-up function has no effect because the
fL 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 tL clock cycles of the LIRC oscillator for the system
to wake-up. The system will then initially run under the fL 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)
0
1024 HXT cycles
1024 HXT cycles
1~2 HXT cycles
1
1024 HXT cycles
1~2 fL cycles (System runs with fL first
for 1024 HXT cycles and then switches
over to run with the HXT clock)
1~2 HXT cycles
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
HXT
Wake-up Time
(IDLE0 Mode)
Wake-up Time
(IDLE1 Mode)
Wake-Up Times
Note that if the Watchdog Timer is disabled, which means that the LIRC is off, then there will be no
Fast Wake-up function available when the device wakes-up from the SLEEP0 Mode.
Rev. 1.30
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I/O Flash USB 8-Bit MCU with SPI
­ €    
­ €    Operating Mode Switching and Wake-up
The device 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 the device enters 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 the device moves between the various operating modes.
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 LIRC oscillator 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. 1.30
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December 11, 2013
HT68FB540/HT68FB550/HT68FB560
I/O Flash USB 8-Bit MCU with SPI
  
   ­   ­       ­   ­  €‚ ƒ    ­   ­  €‚ ƒ    ­   ­    
     ­          ­   € ‚      ­   € ‚      ­   Rev. 1.30
56
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I/O Flash USB 8-Bit MCU with SPI
SLOW Mode to NORMAL Mode Switching
In SLOW Mode the system uses the 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.
Entering the SLEEP0 Mode
There is only one way for the device 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 and WDT 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.
Entering the SLEEP1 Mode
There is only one way for the device 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 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.
Rev. 1.30
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I/O Flash USB 8-Bit MCU with SPI
Entering the IDLE0 Mode
There is only one way for the device 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 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 the device 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 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.
Standby Current Considerations
As the main reason for entering the SLEEP or IDLE Mode is to keep the current consumption of the
device 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 the device. 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 LIRC oscillator is enabled.
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 microamps
Rev. 1.30
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I/O Flash USB 8-Bit MCU with SPI
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 PA and a falling edge on PB~PE, except for PE1
• A system interrupt
• A WDT overflow
If the system is woken up by an external or USB reset, the device will experience a full system reset,
however, if the device is 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 Ports can be setup using the PAWU and PXWU registers to permit a negative transition
on the pin to wake-up the system. When a Port 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 the device
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.
Programming Considerations
• If the device is woken up from the SLEEP0 Mode to the NORMAL Mode, the high speed system
oscillator needs an SST period. The device will execute first instruction after HTO is "1".
• If the device is 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 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 fL depends upon whether the WDT is enabled or disabled as the WDT
clock source is generated from fL.
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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 is sourced from the
LIRC oscillator. 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
Rev. 1.30
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~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
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 time-out period.
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CTRL Register
Bit
7
6
5
4
3
2
1
0
Name
FSYSON
—
—
—
—
LVRF
LRF
WRF
R/W
R/W
—
—
—
—
R/W
R/W
R/W
POR
0
—
—
—
—
x
0
0
Bit 7
FSYSON: fSYS control in IDLE Mode
Described elsewhere.
Bit 6~3
"—": unimplemented, read as "0"
Bit 2
LVRF: LVR function reset flag
Described elsewhere.
Bit 1
LRF: LVR control register software reset flag
Described elsewhere.
Bit 0
WRF: 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 the device. 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.
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 the
device after 2~3 LIRC clock cycles. After power on these bits will have the value of 01010B.
WDT
Controlled by WDT Control Register
WE4~WE0 Bits
WDT Function
10101B
Disable
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. Three 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 and the third is via
a HALT instruction. 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.
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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.
  ‚ ƒ ‚ € „            ­ ­   
€
 
Watchdog Timer
Reset and Initialisation
A reset function is a fundamental part of any microcontroller ensuring that the device can be set to
some predetermined condition irrespective of outside parameters. A hardware reset will of course
be automatically implemented after the device is powered-on, however there are a number of other
hardware and software reset sources that can be implemented dynamically when the device is
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.
The 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.
Reset Name
Abbreviation Indication Bit
Register
Notes
Power-on reset
POR
—
—
Auto generated at power on
Reset pin
RES
—
—
Hardware reset
Low voltage reset
LVR
LVRF
CTRL
Watchdog reset
WDT
TO
STATUS
WDTC register setting
software reset
—
WRF
CTRL
Write to WDTC register
LVRC register setting
sofrware reset
—
LRF
CTRL
Write to LVRC register
Low VDD voltage
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.
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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.
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.
Note: tRSTD is power-on delay, typical time= 50ms
Power-on Reset Timing Chart
RES Pin
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.
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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.
External RES Circuit
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.
Note: tRSTD is power-on delay, typical time= 16.7ms
RES Reset Timing Chart
Low Voltage Reset – LVR
The microcontroller contains a low voltage reset circuit in order to monitor the supply voltage of the
device and provide an MCU reset should the value fall below a certain predefined level.
• LVR Operation
The LVR function is always enabled with a specific LVR voltage VLVR. If the supply voltage of
the device 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 device 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 A.C. 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 device 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 device
enters the power down mode.
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Note: tRSTD is power-on delay, typical time= 16.7ms
Low Voltage Reset Timing Chart
• 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 7~0
LVS7~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
Rev. 1.30
Bit
7
6
5
4
3
2
1
0
Name
FSYSON
—
—
—
—
R/W
R/W
—
—
—
—
LVRF
LRF
WRF
R/W
R/W
R/W
POR
0
—
—
—
—
x
0
0
Bit 7
FSYSON: fSYS Control in IDLE Mode
Describe elsewhere.
Bit 6~3
"—": unimplemented, read as "0"
Bit 2
LVRF: 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 1
LRF: 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 0
WRF: 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".
Note: tRSTD is power-on delay, typical time= 16.7ms
WDT Time-out Reset during Normal Operation Timing Chart
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.
Note:The tSST is 15~16 clock cycles if the system clock source is provided by HIRC. The tSST is
1024 clock for HXT. The tSST is 1~2 clock for LIRC.
WDT Time-out Reset during SLEEP or IDLE Timing Chart
• 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. 1.30
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
PDF
0
0
Power-on reset
RESET Conditions
u
u
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
Program Counter
Interrupts
WDT
Condition After RESET
Reset to zero
All interrupts will be disabled
Clear after reset, WDT begins counting
Timer/Event Counter
Timer Counter will be turned off
Input/Output Ports
I/O ports will be setup as inputs
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.
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• The HT68FB540 register states are summarized below:
WDT Timeout/WDTC
Reset
Register
Software
(Power On)
Reset (Normal
Operation)
RES
Reset/LVRC
Software
Reset (Normal
Operation)
RES
Reset
(HALT)
WDT
Time-out
(HALT)*
USB-reset
(Normal)
USB-reset
(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
---- ---0
---- ---0
---- ---0
---- ---0
---- ---u
---- ---0
---- ---0
SMOD
0000 0011
0000 0011
0000 0011
0000 0011
uuuu uuuu
0000 0011
0000 0011
INTEG
0000 0000
0000 0000
0000 0000
0000 0000
uuuu uuuu
0000 0000
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
00-0 00-0
00-0 00-0
00-0 00-0
00-0 00-0
uu-u uu-u
00-0 00-0
00-0 00-0
INTC2
0000 0000
0000 0000
0000 0000
0000 0000
uuuu uuuu
0000 0000
0000 0000
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
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
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
PE
---- -101
---- -101
---- -101
---- -101
---- -uuu
---- -101
---- -101
PEC
- - - - - 111
- - - - - 111
- - - - - 111
- - - - - 111
---- -uuu
- - - - - 111
- - - - - 111
WDTC
0101 0011
0101 0011
0101 0011
0101 0011
uuuu uuuu
0101 0011
0101 0011
FRCR
---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
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-
uuuu uuu-
1110 000-
1110 000-
SIMC1
1000 0001
1000 0001
1000 0001
1000 0001
uuuu uuuu
1000 0001
1000 0001
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Reset
Register
(Power On)
WDT Timeout/WDTC
Software
Reset (Normal
Operation)
RES
Reset/LVRC
Software
Reset (Normal
Operation)
RES
Reset
(HALT)
WDT
Time-out
(HALT)*
USB-reset
(Normal)
USB-reset
(HALT)
SIMD
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
xxxx xxxx
xxxx xxxx
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 -
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
0000 ---0
0000 ---0
0000 ---0
0000 ---0
uuuu ---u
0000 ---0
0000 ---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
-0-- --00
-0-- --00
-0-- --00
-0-- --00
-u-- --uu
-0-- --00
-0-- --00
PXWU
-0-- --00
-0-- --00
-0-- --00
-0-- --00
-u-- --uu
-0-- --00
-0-- --00
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
---- --uu
---- --00
---- --00
TM1AL
0000 0000
0000 0000
0000 0000
0000 0000
uuuu uuuu
0000 0000
0000 0000
TM1AH
---- --00
---- --00
---- --00
---- --00
---- --uu
---- --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
---- --uu
---- --00
---- --00
TM2AL
0000 0000
0000 0000
0000 0000
0000 0000
uuuu uuuu
0000 0000
0000 0000
TM2AH
---- --00
---- --00
---- --00
---- --00
---- --uu
---- --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
TM3DH
---- --00
---- --00
---- --00
---- --00
---- --uu
---- --00
---- --00
TM3AL
0000 0000
0000 0000
0000 0000
0000 0000
uuuu uuuu
0000 0000
0000 0000
TM3AH
---- --00
---- --00
---- --00
---- --00
---- --uu
---- --00
---- --00
USB_
STAT
11xx 000-
11xx 000-
11xx 000-
11xx 000-
11xx 000-
11xx 000-
11xx 000-
Rev. 1.30
69
December 11, 2013
HT68FB540/HT68FB550/HT68FB560
I/O Flash USB 8-Bit MCU with SPI
Reset
Register
(Power On)
WDT Timeout/WDTC
Software
Reset (Normal
Operation)
RES
Reset/LVRC
Software
Reset (Normal
Operation)
RES
Reset
(HALT)
WDT
Time-out
(HALT)*
USB-reset
(Normal)
USB-reset
(HALT)
UINT
---- 0000
---- uuuu
---- 0000
---- 0000
---- uuuu
---- 0000
---- 0000
USC
1000 0000
uuuu xuux
1000 0000
1000 0000
uuuu xuux
1uuu 0100
1uuu 0100
USR
---- 0000
---- uuuu
---- 0000
---- 0000
---- uuuu
---- 0000
---- 0000
UCC
0000 0-00
uuuu u-uu
0000 0-00
0000 0-00
uuuu u-uu
0uu0 u-00
0uu0 u-00
AWR
0000 0000
uuuu uuuu
0000 0000
0000 0000
uuuu uuuu
0000 0000
0000 0000
STLI
---- 0000
---- uuuu
---- 0000
---- 0000
---- uuuu
---- 0000
---- 0000
STLO
---- 0000
---- uuuu
---- 0000
---- 0000
---- uuuu
---- 0000
---- 0000
SIES
00-0 0000
uu-x xuuu
00-0 0000
00-0 0000
uu-x xuuu
00-0 0000
00-0 0000
MISC
000- 0000
xxu- uuuu
000- 0000
000- 0000
xxu- uuuu
000- 0000
000- 0000
UFIEN
---- 0000
---- uuuu
---- 0000
---- 0000
---- uuuu
---- 0000
---- 0000
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
---- 0000
---- 0000
---- uuuu
---- 0000
---- 0000
UFC0
0000 00--
uuuu uu--
0000 00--
0000 00--
uuuu uu--
0000 00--
0000 00--
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. 1.30
70
December 11, 2013
HT68FB540/HT68FB550/HT68FB560
I/O Flash USB 8-Bit MCU with SPI
• The HT68FB550 register states are summarized below:
WDT TimeRES
out/WDTC
Reset/LVRC
Reset
Register
Software Reset Software Reset
(Power On)
(Normal
(Normal
Operation)
Operation)
RES
Reset
(HALT)
WDT
Time-out
(HALT)*
USB-reset
(Normal)
USB-reset
(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
---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
BP
---- --00
---- ---00
---- --00
---- --00
---- --uu
---- --00
---- --00
SMOD
0000 0011
0000 0011
0000 0011
0000 0011
uuuu uuuu
0000 0011
0000 0011
INTEG
0000 0000
0000 0000
0000 0000
0000 0000
uuuu uuuu
0000 0000
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
00-0 00-0
00-0 00-0
00-0 00-0
00-0 00-0
uu-u uu-u
00-0 00-0
00-0 00-0
INTC2
0000 0000
0000 0000
0000 0000
0000 0000
uuuu uuuu
0000 0000
0000 0000
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
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
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
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
---- -101
---- -101
---- -101
---- -101
---- -uuu
---- -101
---- -101
PEC
- - - - - 111
- - - - - 111
- - - - - 111
- - - - - 111
---- -uuu
- - - - - 111
- - - - - 111
WDTC
0101 0011
0101 0011
0101 0011
0101 0011
uuuu uuuu
0101 0011
0101 0011
FRCR
---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
xxxx xxxx
xxxx xxxx
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
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
Rev. 1.30
71
December 11, 2013
HT68FB540/HT68FB550/HT68FB560
I/O Flash USB 8-Bit MCU with SPI
WDT TimeRES
out/WDTC
Reset/LVRC
Reset
Register
Software Reset Software Reset
(Power On)
(Normal
(Normal
Operation)
Operation)
RES
Reset
(HALT)
WDT
Time-out
(HALT)*
USB-reset
(Normal)
USB-reset
(HALT)
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-
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
uuuu uuuu
xxxx xxxx
xxxx xxxx
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 -
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
0000 ---0
0000 ---0
0000 ---0
0000 ---0
uuuu ---u
0000 ---0
0000 ---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 --00
-000 --00
-000 --00
-000 --00
-uuu --uu
-000 --00
-000 --00
PXWU
-000 --00
-000 --00
-000 --00
-000 --00
-uuu --uu
-000 --00
-000 --00
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
---- --uu
---- --00
---- --00
TM1AL
0000 0000
0000 0000
0000 0000
0000 0000
uuuu uuuu
0000 0000
0000 0000
TM1AH
---- --00
---- --00
---- --00
---- --00
---- --uu
---- --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
---- --uu
---- --00
---- --00
TM2AL
0000 0000
0000 0000
0000 0000
0000 0000
uuuu uuuu
0000 0000
0000 0000
TM2AH
---- --00
---- --00
---- --00
---- --00
---- --uu
---- --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
TM3DH
---- --00
---- --00
---- --00
---- --00
---- --uu
---- --00
---- --00
Rev. 1.30
72
December 11, 2013
HT68FB540/HT68FB550/HT68FB560
I/O Flash USB 8-Bit MCU with SPI
WDT TimeRES
out/WDTC
Reset/LVRC
Reset
Register
Software Reset Software Reset
(Power On)
(Normal
(Normal
Operation)
Operation)
RES
Reset
(HALT)
WDT
Time-out
(HALT)*
USB-reset
(Normal)
USB-reset
(HALT)
TM3AL
0000 0000
0000 0000
0000 0000
0000 0000
uuuu uuuu
0000 0000
0000 0000
TM3AH
---- --00
---- --00
---- --00
---- --00
---- --uu
---- --00
---- --00
USB_
STAT
11xx 000-
11xx 000-
11xx 000-
11xx 000-
11xx 000-
11xx 000-
11xx 000-
UINT
--00 0000
--uu uuuu
--00 0000
--00 0000
--uu uuuu
--00 0000
--00 0000
USC
1000 0000
uuuu xuux
1000 0000
1000 0000
uuuu xuux
1uuu 0100
1uuu 0100
USR
--00 0000
--uu uuuu
--00 0000
--00 0000
--uu uuuu
--00 0000
--00 0000
UCC
0000 0000
uuuu uuuu
0000 0000
0000 0000
uuuu uuuu
0uu0 u000
0uu0 u000
AWR
0000 0000
uuuu uuuu
0000 0000
0000 0000
uuuu uuuu
0000 0000
0000 0000
STLI
--00 0000
--uu uuuu
--00 0000
--00 0000
--uu uuuu
--00 0000
--00 0000
STLO
--00 0000
--uu uuuu
--00 0000
--00 0000
--uu uuuu
--00 0000
--00 0000
SIES
00-0 0000
uu-x xuuu
00-0 0000
00-0 0000
uu-x xuuu
00-0 0000
00-0 0000
MISC
0000 0000
xxuu uuuu
0000 0000
0000 0000
xxuu uuuu
0000 0000
0000 0000
UFIEN
--00 0000
--uu uuuu
--00 0000
--00 0000
--uu uuuu
--00 0000
--00 0000
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
UFOEN
--00 0000
--uu uuuu
--00 0000
--00 0000
--uu uuuu
--00 0000
--00 0000
UFC0
0000 00--
uuuu uu--
0000 00--
0000 00--
uuuu uu--
0000 00--
0000 00--
UFC1
---- 0000
---- uuuu
---- 0000
---- 0000
---- uuuu
---- 0000
---- 0000
PDPS
0000 0000
0000 0000
0000 0000
0000 0000
uuuu uuuu
0000 0000
0000 0000
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. 1.30
73
December 11, 2013
HT68FB540/HT68FB550/HT68FB560
I/O Flash USB 8-Bit MCU with SPI
• The HT68FB560 register states are summarized below:
WDT TimeRES
out/WDTC
Reset/LVRC
Reset
Register
Software Reset Software Reset
(Power On)
(Normal
(Normal
Operation)
Operation)
RES
Reset
(HALT)
WDT
Time-out
(HALT)*
USB-reset
(Normal)
USB-reset
(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
--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
--0- -000
SMOD
0000 0011
0000 0011
0000 0011
0000 0011
uuuu uuuu
0000 0011
0000 0011
INTEG
0000 0000
0000 0000
0000 0000
0000 0000
uuuu uuuu
0000 0000
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
00-0 00-0
00-0 00-0
00-0 00-0
00-0 00-0
uu-u uu-u
00-0 00-0
00-0 00-0
INTC2
0000 0000
0000 0000
0000 0000
0000 0000
uuuu uuuu
0000 0000
0000 0000
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
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
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
WDTC
0101 0011
0101 0011
0101 0011
0101 0011
uuuu uuuu
0101 0011
0101 0011
FRCR
---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
xxxx xxxx
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
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
Rev. 1.30
74
December 11, 2013
HT68FB540/HT68FB550/HT68FB560
I/O Flash USB 8-Bit MCU with SPI
WDT TimeRES
out/WDTC
Reset/LVRC
Reset
Register
Software Reset Software Reset
(Power On)
(Normal
(Normal
Operation)
Operation)
FD3L
xxxx xxxx
xxxx xxxx
xxxx xxxx
RES
Reset
(HALT)
WDT
Time-out
(HALT)*
USB-reset
(Normal)
USB-reset
(HALT)
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-
uuuu uuu-
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
uuuu uuuu
xxxx xxxx
xxxx xxxx
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 -
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
0000 ---0
0000 ---0
0000 ---0
0000 ---0
uuuu ---u
0000 ---0
0000 ---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
PXWU
0000 0000
0000 0000
0000 0000
0000 0000
uuuu uuuu
0000 0000
0000 0000
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
---- --uu
---- --00
---- --00
TM1AL
0000 0000
0000 0000
0000 0000
0000 0000
uuuu uuuu
0000 0000
0000 0000
TM1AH
---- --00
---- --00
---- --00
---- --00
---- --uu
---- --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
---- --uu
---- --00
---- --00
TM2AL
0000 0000
0000 0000
0000 0000
0000 0000
uuuu uuuu
0000 0000
0000 0000
TM2AH
---- --00
---- --00
---- --00
---- --00
---- --uu
---- --00
---- --00
TM3C0
0000 0000
0000 0000
0000 0000
0000 0000
uuuu uuuu
0000 0000
0000 0000
Rev. 1.30
75
December 11, 2013
HT68FB540/HT68FB550/HT68FB560
I/O Flash USB 8-Bit MCU with SPI
WDT TimeRES
out/WDTC
Reset/LVRC
Reset
Register
Software Reset Software Reset
(Power On)
(Normal
(Normal
Operation)
Operation)
RES
Reset
(HALT)
WDT
Time-out
(HALT)*
USB-reset
(Normal)
USB-reset
(HALT)
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
---- --00
---- --uu
---- --00
---- --00
TM3AL
0000 0000
0000 0000
0000 0000
0000 0000
uuuu uuuu
0000 0000
0000 0000
TM3AH
---- --00
---- --00
---- --00
---- --00
---- --uu
---- --00
---- --00
USB_
STAT
11xx 000-
11xx 000-
11xx 000-
11xx 000-
11xx 000-
11xx 000-
11xx 000-
UINT
0000 0000
uuuu uuuu
0000 0000
0000 0000
uuuu uuuu
0000 0000
0000 0000
USC
1000 0000
uuuu xuux
1000 0000
1000 0000
uuuu xuux
1uuu 0100
1uuu 0100
USR
0000 0000
uuuu uuuu
0000 0000
0000 0000
uuuu uuuu
0000 0000
0000 0000
UCC
0000 0000
uuuu uuuu
0000 0000
0000 0000
uuuu uuuu
0uu0 u000
0uu0 u000
AWR
0000 0000
uuuu uuuu
0000 0000
0000 0000
uuuu uuuu
0000 0000
0000 0000
STLI
0000 0000
uuuu uuuu
0000 0000
0000 0000
uuuu uuuu
0000 0000
0000 0000
STLO
0000 0000
uuuu uuuu
0000 0000
0000 0000
uuuu uuuu
0000 0000
0000 0000
SIES
00-0 0000
uu-x xuuu
00-0 0000
00-0 0000
uu-x xuuu
00-0 0000
00-0 0000
MISC
0000 0000
xxuu uuuu
0000 0000
0000 0000
xxuu uuuu
0000 0000
0000 0000
UFIEN
0000 0000
00uu uuuu
0000 0000
0000 0000
uuuu uuuu
0000 0000
0000 0000
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
FIFO7
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
xxxx xxxx
UFOEN
0000 0000
00uu uuuu
-0000 0000
0000 0000
uuuu uuuu
0000 0000
0000 0000
UFC0
0000 00--
uuuu uu--
0000 00--
0000 00--
uuuu uu--
0000 00--
0000 00--
UFC1
0000 0000
uuuu uuuu
0000 0000
0000 0000
uuuu uuuu
0000 0000
0000 0000
PDPS
0000 0000
0000 0000
0000 0000
0000 0000
uuuu uuuu
0000 0000
0000 0000
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. 1.30
76
December 11, 2013
HT68FB540/HT68FB550/HT68FB560
I/O 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 provide bidirectional input/output lines labeled with port names PA~PE. 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
• HT68FB540
Register
Name
Rev. 1.30
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
PXWU
—
PELWU
—
—
—
—
PBHWU
PBLWU
PXPU
—
PELPU
—
—
—
—
PBHPU
PBLPU
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
PE
—
—
—
—
—
D2
D1
D0
PEC
—
—
—
—
—
D2
D1
D0
77
December 11, 2013
HT68FB540/HT68FB550/HT68FB560
I/O Flash USB 8-Bit MCU with SPI
• HT68FB550
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
PXWU
—
PELWU
PDHWU
PDLWU
—
—
PBHWU
PBLWU
PXPU
—
PELPU
PDHPU
PDLPU
—
—
PBHPU
PBLPU
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
D7
D6
D5
D4
D3
D2
D1
D0
PDC
D7
D6
D5
D4
D3
D2
D1
D0
PE
—
—
—
—
—
D2
D1
D0
PEC
—
—
—
—
—
D2
D1
D0
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
PXWU
PEHWU
PELWU
PDHWU
PDLWU
PCHWU
PCLWU
PBHWU
PBLWU
PXPU
PEHPU
PELPU
PDHPU
PDLPU
PCHPU
PCLPU
PBHPU
PBLPU
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
• HT68FB560
Rev. 1.30
Bit
78
December 11, 2013
HT68FB540/HT68FB550/HT68FB560
I/O 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 and PXPU, and are implemented using
weak PMOS transistors. Note that the PA pull-high resistors are controlled by bits in the PAPU
register, 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
PAPU: I/O PA bit 7~bit 0 Pull-High Control
0: disable
1: enable
PXPU Register
• HT68FB540
Bit
7
6
5
4
3
2
1
0
Name
—
PELPU
—
—
—
—
PBHPU
PBLPU
R/W
R
R/W
R
R
R
R
R/W
R/W
POR
0
0
0
0
0
0
0
0
Bit 7
"—": unimplemented, read as "0"
Bit 6
PELPU: PE2, PE0 pins Pull-High control
0: disable
1: enable Note that the PE1 pin has no pull-up resistor.
Bit 5~2 "—": unimplemented, read as "0"
Bit 1
PBHPU: PB6~PB4 pins Pull-High control
0: disable
1: enable
Bit 0
PBLPU: PB3~PB0 pins Pull-High control
0: disable
1: enable
• HT68FB550
Rev. 1.30
Bit
7
6
5
4
3
2
1
0
Name
—
PELPU
PDHPU
PDLPU
—
—
PBHPU
PBLPU
R/W
R
R/W
R/W
R/W
R
R
R/W
R/W
POR
0
0
0
0
0
0
0
0
Bit 7
"—": unimplemented, read as "0"
Bit 6
PELPU: PE2, PE0 pins Pull-High control
0: disable
1: enable Note that the PE1 pin has no pull-up resistor.
79
December 11, 2013
HT68FB540/HT68FB550/HT68FB560
I/O Flash USB 8-Bit MCU with SPI
Bit 5
PDHPU: PD7~PD4 pins Pull-High control
0: disable
1: enable
Bit 4
PDLPU: PD3~PD0 pins Pull-High control
0: disable
1: enable
Bit 3~2 "—": unimplemented, read as "0"
Bit 1
PBHPU: PB6~PB4 pins Pull-High control
0: disable
1: enable
Bit 0
PBLPU: PB3~PB0 pins Pull-High control
0: disable
1: enable
• HT68FB560
Rev. 1.30
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 7
PEHPU: PE5~PE4 pins Pull-High control
0: disable
1: enable
Bit 6
PELPU: PE3~PE2, PE0 pins Pull-High control
0: disable
1: enable Note that the PE1 pin has no pull-up resistor.
Bit 5
PDHPU: PD7~PD4 pins Pull-High control
0: disable
1: enable
Bit 4
PDLPU: PD3~PD0 pins Pull-High control
0: disable
1: enable
Bit 3
PCHPU: PC7~PC4 pins Pull-High control
0: disable
1: enable
Bit 2
PCLPU: PC3~PC0 pins Pull-High control
0: disable
1: enable
Bit 1
PBHPU: PB7~PB4 pins Pull-High control
0: disable
1: enable
Bit 0
PBLPU: PB3~PB0 pins Pull-High control
0: disable
1: enable
80
December 11, 2013
HT68FB540/HT68FB550/HT68FB560
I/O Flash USB 8-Bit MCU with SPI
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 E 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 E can be selected by bits or nibble to have
this wake-up feature using the PAWU and PXWU 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 7~0
PAWU: Port A bit 7~bit 0 Wake-up Control
0: disable
1: enable
PXWU Register
• HT68FB540
Bit
7
6
5
4
3
2
1
0
Name
—
PELWU
—
—
—
—
PBHWU
PBLWU
R/W
R
R/W
R
R
R
R
R/W
R/W
POR
0
0
0
0
0
0
0
0
Bit 7
"—": unimplemented, read as "0"
Bit 6
PELWU: PE2, PE0 pins Wake-up control
0: disable
1: enable Note that the PE1 pin has no wake-up function.
Bit 5~2 "—": unimplemented, read as "0"
Bit 1
PBHWU: PB6~PB4 pins Wake-up control
0: disable
1: enable
Bit 0
PBLWU: PB3~PB0 pins Wake-up control
0: disable
1: enable
• HT68FB550
Rev. 1.30
Bit
7
6
5
4
3
2
1
0
Name
—
PELWU
PDHWU
PDLWU
—
—
PBHWU
PBLWU
R/W
R
R/W
R/W
R/W
R
R
R/W
R/W
POR
0
0
0
0
0
0
0
0
Bit 7
"—": unimplemented, read as "0"
Bit 6
PELWU: PE2, PE0 pins Wake-up control
0: disable
1: enable Note that the PE1 pin has no wake-up function.
81
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I/O Flash USB 8-Bit MCU with SPI
Bit 5
PDHWU: PD7~PD4 pins Wake-up control
0: disable
1: enable
Bit 4
PDLWU: PD3~PD0 pins Wake-up control
0: disable
1: enable
Bit 3~2
"—": unimplemented, read as "0"
Bit 1
PBHWU: PB6~PB4 pins Wake-up control
0: disable
1: enable
Bit 0
PBLWU: PB3~PB0 pins Wake-up control
0: disable
1: enable
• HT68FB560
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 7
PEHWU: PE5~PE4 pins Wake-up control
0: disable
1: enable
Bit 6
PELWU: PE3~PE2, PE0 pins Wake-up control
0: disable
1: enable Note that the PE1 pin has no wake-up function.
Bit 5
PDHWU: PD7~PD4 pins Wake-up control
0: disable
1: enable
Bit 4
PDLWU: PD3~PD0 pins Wake-up control
0: disable
1: enable
Bit 3
PCHWU: PC7~PC4 pins Wake-up control
0: disable
1: enable
Bit 2
PCLWU: PC3~PC0 pins Wake-up control
0: disable
1: enable
Bit 1
PBHWU: PB7~PB4 pins Wake-up control
0: disable
1: enable
Bit 0
PBLWU: PB3~PB0 pins 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.
Rev. 1.30
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I/O Flash USB 8-Bit MCU with SPI
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~PEC, 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
PBC Register
• HT68FB540/HT68FB550
Bit
7
6
5
4
3
2
1
0
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
• HT68FB560
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
• HT68FB560
Rev. 1.30
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
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I/O Flash USB 8-Bit MCU with SPI
PDC Register
• HT68FB550/HT68FB560
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
PEC Register
• HT68FB540/HT68FB550
Bit
7
6
5
4
3
2
1
0
Name
—
—
—
—
—
D2
D1
D0
R/W
—
—
—
—
—
R/W
R/W
R/W
POR
—
—
—
—
—
1
1
1
• HT68FB560
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
Bit 7~6
Bit 5~0
"—": unimplemented, read as "0"
PEC: I/O Port bit 5~bit 0 Input/Output Control
0: Output
1: Input
Port A , Port D Power Source Control Registers
Port A and Port D can be setup to have a choice of various power source using specific registers.
Each pin on Port A and Port D [7:4] can be selected individually to have various power sources
using the PAPS0, PAPS1 and PDPS 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
Bit 5~4
Bit 3~2
Bit 1~0
Rev. 1.30
PA3S1, PA3S0: PA3 power supply control 00: VDD
01: VDD
10: VDDIO
11: V33O, 3.3V regulator output
PA2S1, PA2S0: PA2 power supply control 00: VDD
01: VDD
10: VDDIO 11: V33O, 3.3V regulator output
PA1S1, PA1S0: PA1 power supply control 00: VDD
01: VDD
10: VDDIO 11: V33O, 3.3V regulator output
PA0S1, PA0S0: PA0 power supply control 00: VDD
01: VDD
10: VDDIO 11: V33O, 3.3V regulator output
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I/O Flash USB 8-Bit MCU with SPI
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 7~6
PA7S1, PA7S0: PA7 power supply control 00: VDD
01: VDD
10: VDDIO 11: V33O, 3.3V regulator output Bit 5~4
PA6S1, PA6S0: PA6 power supply control 00: VDD
01: VDD
10: VDDIO 11: V33O, 3.3V regulator output Bit 3~2
PA5S1, PA5S0: PA5 power supply control 00: VDD
01: VDD
10: VDDIO 11: V33O, 3.3V regulator output Bit 1~0
PA4S1, PA4S0: PA4 power supply control 00: VDD
01: VDD
10: VDDIO 11: V33O, 3.3V regulator output PDPS Register
• HT68FB550/HT68FB560
Rev. 1.30
Bit
7
6
5
4
3
2
1
0
Name
PD7S1
PD7S0
PD6S1
PD6S0
PD5S1
PD5S0
PD4S1
PD4S0
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
PD7S1, PD7S0: PD7 power supply control 00: VDD
01: VDD
10: VDDIO 11: V33O, 3.3V regulator output Bit 5~4
PD6S1, PD6S0: PD6 power supply control 00: VDD
01: VDD
10: VDDIO 11: V33O, 3.3V regulator output Bit 3~2
PD5S1, PD5S0: PD5 power supply control 00: VDD
01: VDD
10: VDDIO 11: V33O, 3.3V regulator output Bit 1~0
PD4S1, PD4S0: PD4 power supply control 00: VDD
01: VDD
10: VDDIO 11: V33O, 3.3V regulator output 85
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I/O Flash USB 8-Bit MCU with SPI
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.
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~PEC, 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~PE, 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 while it has
to be set by nibble pins in the Port B, Port C, Port D and Port E. When the device is in the SLEEP
or IDLE Mode, various methods are available to wake the device up. One of these is a voltage level
transition on any of the Port pins. Single or multiple pins on Ports can be setup to have this function.
    
 Generic Input/Output Structure
Rev. 1.30
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I/O Flash USB 8-Bit MCU with SPI
Timer Modules – TM
One of the most fundamental functions in any microcontroller device is 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.
Function
CTM
STM
Timer/Counter
√
√
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
HT68FB540/HT68FB550/HT68FB560
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.
Rev. 1.30
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I/O 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 either the system clock fSYS or the internal high
clock fH, the fL clock source 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 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 device is 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.
Device
CTM
STM
Registers
HT68FB540
HT68FB550
HT68FB560
TP2_0, TP2_1
TP3_0, TP3_1
TP0_0, TP0_1
TP1_0, TP1_1
TMPC0,
TMPC1
TM Output Pins
Rev. 1.30
88
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I/O 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 one or 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
Device
Bit
7
6
5
4
3
2
1
0
TMPC0
HT68FB540
HT68FB550
HT68FB560
—
—
T1CP1
T1CP0
—
—
T0CP1
T0CP0
TMPC1
HT68FB540
HT68FB550
HT68FB560
—
—
T3CP1
T3CP0
—
—
T2CP1
T2CP0
TM Input/Output Pin Control Registers List
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.
Rev. 1.30
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I/O Flash USB 8-Bit MCU with SPI
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.
TM2 Function Pin Control Block Diagram
Note: The I/O register data bits shown are used for TM output inversion control.
Rev. 1.30
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I/O Flash USB 8-Bit MCU with SPI
TM3 Function Pin Control Block Diagram
Note: The I/O register data bits shown are used for TM output inversion control.
TMPC0 Register
Bit
7
6
5
4
3
2
1
0
Name
—
—
T1CP1
T1CP0
—
—
T0CP1
T0CP0
R/W
R
R
R/W
R/W
R
R
R/W
R/W
POR
0
0
0
1
0
0
0
1
Bit 7~6 "—": unimplemented, read as "0"
Rev. 1.30
Bit 5
T1CP1: TP1_1 pin Control
0: disable
1: enable
Bit 4
T1CP0: TP1_0 pin Control
0: disable
1: enable
Bit 3~2
"—": unimplemented, read as "0"
Bit 1
T0CP1: TP0_1 pin Control
0: disable
1: enable
Bit 0
T0CP0: TP0_0 pin Control
0: disable
1: enable
91
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I/O Flash USB 8-Bit MCU with SPI
TMPC1 Register
Bit
7
6
5
4
3
2
1
0
Name
—
—
T3CP1
T3CP0
—
—
T2CP1
T2CP0
R/W
R
R
R/W
R/W
R
R
R/W
R/W
POR
0
0
0
1
0
0
0
1
Bit 7~6 "—": unimplemented, read as "0"
Bit 5
T3CP1: TP3_1 pin Control
0: disable
1: enable
Bit 4
T3CP0: TP3_0 pin Control
0: disable
1: enable
Bit 3~2
"—": unimplemented, read as "0"
Bit 1
T2CP1: TP2_1 pin Control
0: disable
1: enable
Bit 0
T2CP0: TP2_0 pin Control
0: disable
1: enable
Programming Considerations
The TM Counter Registers and the Capture/Compare CCRA register, being either 10-bit or 16bit, 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.
 Rev. 1.30
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I/O Flash USB 8-Bit MCU with SPI
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 CCRA
♦♦
Step 1. Read data from the High Byte TMxDH or 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 or TMxAL
– this step reads data from the 8-bit buffer.
As the CCRA register implemented in the way shown in the following diagram and accessing these
register pairs 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.
Compact Type TM
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 two external output
pins. These two external output pins can be the same signal or the inverse signal.
CTM
Name
TM No.
TM Input Pin
TM Output Pin
HT68FB540
HT68FB550
HT68FB560
10-bit CTM
2,3
TCK2, TCK3
TP2_0, TP2_1,
TP3_0, TP3_1,
€‚
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€† „‡ …
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 
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 
  ­ ­     Compact Type TM Block Diagram
Rev. 1.30
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I/O Flash USB 8-Bit MCU with SPI
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.
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.
Name
Bit7
Bit6
Bit5
Bit4
Bit3
Bit2
Bit1
Bit0
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 7~0
TMnDL: TMn Counter Low Byte Register bit 7 ~ bit 0
TMn 10-bit Counter bit 7 ~ bit 0
TMnDH Register
Rev. 1.30
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 1~0
TMnDH: TMn Counter High Byte Register bit 1~bit 0
TMn 10-bit Counter bit 9~bit 8
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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
1
0
Bit 7~0
TMnAL: 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
Name
—
—
—
—
—
—
D9
D8
R/W
—
—
—
—
—
—
R/W
R/W
POR
—
—
—
—
—
—
0
0
Bit 7~2
"—": unimplemented, read as "0"
Bit 1~0
TMnAH: TMn CCRA High Byte Register bit 1~bit 0
TMn 10-bit CCRA bit 9~bit 8
TMnC0 Register
Rev. 1.30
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 7
TnPAU: 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 6~4
TnCK2~TnCK0: Select TMn Counter clock
000: fSYS/4
001: fSYS
010: fH/16
011: fH/64
100: fL
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 fL are other internal clocks, the details of which
can be found in the oscillator section.
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Bit 3
TnON: 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 2~0
TnRP2~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.
TMnC1 Register
Rev. 1.30
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 7~6
TnM1 ~ 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 5~4
TnIO1~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
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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. 1.30
Bit 3
TnOC: 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 2
TnPOL: 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 1
TnDPX: 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 0
TnCCLR: 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.
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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 its 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. 1.30
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Counter Value
Counter overflow
CCRP=0
0x3FF
TnCCLR = 0; TnM [1:0] = 00
CCRP > 0
Counter cleared by CCRP value
CCRP > 0
Counter
Restart
Resume
CCRP
Pause
CCRA
Stop
Time
TnON
TnPAU
TnPOL
CCRP Int.
Flag TnPF
CCRA Int.
Flag TnAF
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= 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. 1.30
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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
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.
Rev. 1.30
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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 = 7.8125kHz, 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%.
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. 1.30
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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. 1.30
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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. 1.30
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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
HT68FB540
HT68FB550
HT68FB560
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-bits wide whose value is compared the with 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. 1.30
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I/O 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
Name
Bit7
Bit6
Bit5
Bit4
Bit3
Bit2
Bit1
Bit0
TM0C0
T0PAU
T0CK2
T0CK1
T0CK0
T0ON
—
—
—
TM0C1
T0M1
T0M0
T0IO1
T0IO0
T0OC
T0POL
T0PX
T0CLR
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
Rev. 1.30
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
R
R
R
POR
0
0
0
0
0
0
0
0
Bit 7
T0PAU: 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
T0CK2, T0CK1, T0CK0: Select TM0 Counter clock
000: fSYS/4
001: fSYS
010: fH/16
011: fH/64
100: fL
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 fL are other internal clocks, the details of which can be
found in the oscillator section.
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Bit 3
Bit 2~0
T0ON: 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.
"—": unimplemented, read as "0"
• TM0C1 Register
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 7~6
Bit 5~4
T0M1~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.
T0IO1~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.
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.
Rev. 1.30
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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 3
T0OC: 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 2
T0POL: 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 1
T0DPX: 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 0
T0CCLR: 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.
• TM0DL 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 7~0
Rev. 1.30
TM0DL: TM0 Counter Low Byte Register bit 7~bit 0
TM0 16-bit Counter bit 7~bit 0
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• TM0DH Register
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 7~0
TM0DH: TM0 Counter High Byte Register bit 7~bit 0
TM0 16-bit Counter bit 15~bit 8
• TM0AL 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
TM0AL: TM0 CCRA Low Byte Register bit 7~bit 0
TM0 16-bit CCRA bit 7~bit 0
• TM0AH Register
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
Bit 7~0
TM0AH: TM0 CCRA High Byte Register bit 7~bit 0
TM0 16-bit CCRA bit 15~bit 8
• TM0RP 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
TM0RP: 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 x (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.
10-bit Standard TM Register List
Rev. 1.30
Name
Bit7
Bit6
Bit5
Bit4
Bit3
Bit2
Bit1
Bit0
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
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• 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 7
Bit 6~4
Bit 3
Bit 2~0
Rev. 1.30
T1PAU: 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.
T1CK2~T1CK0: Select TM1 Counter clock
000: fSYS/4
001: fSYS
010: fH/16
011: fH/64
100: fL
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 fL are other internal clocks, the details of which can be
found in the oscillator section.
T1ON: 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.
T1RP2~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.
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• TM1C1 Register
Rev. 1.30
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 7~6
T1M1~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 5~4
T1IO1~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 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
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Bit 3
T1OC: 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 2
T1POL: 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 1
T1DPX: 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 0
T1CCLR: 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.
• 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
Bit 7~0
TM1DL: TM1 Counter Low Byte Register bit 7~bit 0
TM1 10-bit Counter bit 7~bit 0
• TM1DH Register
Rev. 1.30
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 1~0
TM1DH: TM1 Counter High Byte Register bit 1~bit 0
TM1 10-bit Counter bit 9~bit 8
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• 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
1
0
Bit 7~0
TM1AL: 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
2
Name
—
—
—
—
—
—
D9
D8
R/W
—
—
—
—
—
—
R/W
R/W
POR
—
—
—
—
—
—
0
0
Bit 7~2
"—": unimplemented, read as "0"
Bit 1~0
TM1AH: TM1 CCRA High Byte Register bit 1~bit 0
TM1 10-bit CCRA bit 9~bit 8
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 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. 1.30
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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.
Counter Value
Counter overflow
CCRP=0
0x3FF
TnCCLR = 0; TnM [1:0] = 00
CCRP > 0
Counter cleared by CCRP value
CCRP > 0
Counter
Restart
Resume
CCRP
Pause
CCRA
Stop
Time
TnON
TnPAU
TnPOL
CCRP Int.
Flag TnPF
CCRA Int.
Flag TnAF
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= 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. 1.30
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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. A TnPF flag is not generated when TnCCLR= 1
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.
Rev. 1.30
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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
000b
Period
CCRP x 256
65536
Duty
CCRA
If fSYS = 16MHz, TM clock source select fSYS/4, CCRP = 2 and CCRA = 128,
The STM PWM output frequency = (fSYS/4)/(2x256)= 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
000b
CCRA
65536
CCRP x 256
Duty
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 x 256) except when CCRP value is equal to 000b.
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.
Rev. 1.30
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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
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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
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
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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
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 hight
5. In the Single Pulse Mode, TnIO [1:0] must be set to "11" and can not be changed.
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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.
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Counter Value
TnM [1:0] = 01
Counter cleared
by CCRP
Counter Counter
Stop
Reset
CCRP
YY
Pause
Resume
XX
Time
TnON
TnPAU
TM capture
pin TPn_x
Active
edge
Active
edge
Active edge
CCRA Int.
Flag TnAF
CCRP Int.
Flag TnPF
CCRA
Value
TnIO [1:0]
Value
XX
00 – Rising edge
YY
01 – Falling edge
XX
10 – Both edges
YY
11 – Disable Capture
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.
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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, SA_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 device can be
either master or slave. Although the SPI interface specification can control multiple slave devices
from a single master, but this device provided 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 pinshared 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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The SPI function in these devices offer 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 device
is in the master or slave mode and upon the condition of certain control bits such as CSEN and
SIMEN.
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
D7
D6
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 device writes 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
device can read it from the SIMD register. Any transmission or reception of data from the SPI bus
must be made via the SIMD register.
The SIM_WCOL bit in the SBSC register is used to control the SPI WCOL function.
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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 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.
SIMC0 Register
Rev. 1.30
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
R
POR
1
1
1
0
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 fL
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 fL or TM0. If the SPI Slave Mode is selected
then the clock will be supplied by an external Master device.
Bit 4
PCKEN: 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
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Bit 1
SIMEN: 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
"—": unimplemented, read as "0"
SIMC2 Register
Bit
Rev. 1.30
7
6
5
4
3
2
1
0
Name
D7
D6
CKPOLB
CKEG
MLS
CSEN
WCOL
TRF
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
Undefined bit
This bit can be read or written by the application program.
Bit 5
CKPOLB: 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 4
CKEG: 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 3
MLS: 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.
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Bit 2
CSEN: 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 1
WCOL: 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 0
TRF: 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.
SBSC Register
Bit
7
6
5
4
Name
R/W
POR
3
SIM_WCOL
—
I2CDB1
I2CDB0
—
R/W
—
R/W
R/W
—
0
—
0
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
Related to SPIA function, described elsewhere
2
1
0
—
—
SA_WCOL
—
—
R/W
—
0
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 device 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 Master Mode Timing
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SPI Slave Mode Timing – CKEG=1
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   SPI Transfer Control Flowchart
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 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 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 device.
• 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 device.
• 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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I/O Flash USB 8-Bit MCU with SPI
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.
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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.
Rev. 1.30
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I/O Flash USB 8-Bit MCU with SPI
Bit
Register
Name
7
SIMC0
SIMC1
SIMD
6
5
4
3
2
1
0
SIM2
SIM1
SIM0
PCKEN
PCKP1
PCKP0
SIMEN
—
HCF
HAAS
HBB
HTX
TXAK
SRW
IAMWU
RXAK
D7
D6
D5
D4
D3
D2
D1
D0
SIMA
IICA6
IICA5
IICA4
IICA3
IICA2
IICA1
IICA0
D0
SBSC
SIM_WCOL
—
I2CDB1
I2CDB0
—
—
—
SA_WCOL
I2C Registers List
• SIMC0 Register
Rev. 1.30
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
R
POR
1
1
1
0
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 fL
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 fL or TM0. If the SPI Slave Mode is selected
then the clock will be supplied by an external Master device.
Bit 4
PCKEN: 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 1
SIMEN: 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 HTXand 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".
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• SIMC1 Register
Rev. 1.30
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 7
HCF: I2C 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.
Bit 6
HAAS: I2C Bus address match flag
0: Not address match
1: Address match
The HASS 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 5
HBB: 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 4
HTX: Select I2C slave device is transmitter or receiver
0: Slave device is the receiver
1: Slave device is the transmitter
Bit 3
TXAK: 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.
Bit 2
SRW: 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 1
IAMWU: 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.
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Bit 0
RXAK: 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 device writes 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 device 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
• 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
R/W
POR
x
x
x
x
x
x
x
0
"x" unknown
Bit 7~1
IICA6~ 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
Rev. 1.30
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 7
SIM_WCOL : SIM WCOL control bit
Related to SPI, described elsewhere.
Bit 6
"—": unimplemented, read as "0"
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I/O Flash USB 8-Bit MCU with SPI
I2CDB1, I2CDB0: I2C debounce selection bits
00: No debounce (default)
01: 1 system clock debounce
10, 11: 2 system clocks debounce
Bit 5~4
Bit 3~1
"—": unimplemented, read as "0"
Bit 0
SA_WCOL : SPIA WCOL function control
Related to SPIA, described elsewhere.
  † †     „  … ‚ €  € ƒ „    ­ €   
‡ I2C Block Diagram
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 bit to determine whether the
interrupt source originates from an address match or from the completion of an 8-bit data transfer.
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 "1" 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.
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I/O Flash USB 8-Bit MCU with SPI

 € ‚   ƒ „ … ‚     ­
  ­
I2C Bus Initialisation Flow Chart
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.
I2C Bus 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 I 2C bus interrupt can come from two sources, when the program enters the interrupt
subroutine, the HAAS bit 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. When a slave address is
matched, the device 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.
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I/O Flash USB 8-Bit MCU with SPI
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" .
I2C Bus Data and Acknowledge Signal
The transmitted data is 8-bits 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.
Rev. 1.30
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I/O Flash USB 8-Bit MCU with SPI
€

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­
         ­ I2C Communication Timing Diagram
Note: *When a slave address is matched, the device 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 ISR Flow Chart
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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
enable/disable and the time-out period are managed by the I2CTOC register.
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
5
4
3
2
1
0
Name
I2CTOEN
I2CTOF
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 7
I2CTOEN: I C Time Out function control bit
0: disable
1: enable Bit 6
I2CTOF: I2C Time Out indication bit
0: Not occurred
1: Occurred
Bit 5~0
I2CTOS5~I2CTOS0: I2C Time out time period select
The I2C Time out clock is provided by the fL/32. The time out time period can be
calculated from the accompanying equation. ([I2CTOS5:I2CTOS0]+1) x (32/fL)
2
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 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 device can be
either master or slave. Although the SPIA interface specification can control multiple slave devices
from a single master, however this device is 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.
Rev. 1.30
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I/O Flash USB 8-Bit MCU with SPI
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
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The SPIA function in this device 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.
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I/O Flash USB 8-Bit MCU with SPI
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
SPIAC0
SASPI2
SASPI1
SPIAC1
—
—
SPIAD
D7
D6
D5
D4
D3
D2
D1
D0
SBSC
SIM_WCOL
—
I2CDB1
I2CDB0
—
—
—
SA_WCOL
5
4
3
2
1
0
SASPI0
—
—
—
SPIAEN
SACKPOL SACKEG SAMLS SACSEN SAWCOL
—
SATRF
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.
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
Rev. 1.30
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
0
0
0
0
Bit 7~5
SASPI2 ~ SASPI0: Master/Slave Clock Select
000 : SPIA master, fSYS/4
001 : SPIA master, fSYS/16
010 : SPIA master, fSYS/64
011 : SPIA master, fL
100 : SPIA master, TM0 CCRP match frequency/2
101 : SPIA slave 110: unimplemented
111: unimplemented
These bits are used to control the SPIA 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. 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"
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I/O Flash USB 8-Bit MCU with SPI
Bit 1
SPIAEN: SPIA enable or disable
0: disable
1: enable The bit is the overall on/off control for the SIMA interface. When the SPIAEN bit
is cleared to zero to disable the SPIA interface, the SDIA, SDOA, SCKA and SCSA
lines will lose their SPI 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
"—": unimplemented, read as "0"
SPIAC1 Register
Rev. 1.30
Bit
7
6
Name
—
—
5
4
R/W
—
—
R/W
R/W
R/W
R/W
R/W
R/W
POR
—
—
0
0
0
0
0
0
SACKPOL SACKEG
3
SAMLS
2
1
SACSEN SAWCOL
0
SATRF
Bit 7~6
"—": unimplemented, read as "0".
This bit can be read or written by user software program.
Bit 5
SACKPOL: 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 4
SACKEG: 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 SPI 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 3
SAMLS: 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 2
SACSEN: 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.
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Bit 1
SAWCOL: 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 0
SATRF: 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.
SBSC Register
Bit
7
6
5
4
Name
R/W
POR
3
SIM_WCOL
—
I2CDB1
I2CDB0
—
R/W
—
R/W
R/W
—
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.
2
1
0
—
—
SA_WCOL
—
—
R/W
—
0
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. 1.30
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I/O Flash USB 8-Bit MCU with SPI
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SPIA Master Mode Timing
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SPIA Slave Mode Timing – SACKEG= 1
Rev. 1.30
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I/O 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. 1.30
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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 SACKPOLB
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 enabl