HT45F77

Body Fat Scale 8-Bit Flash MCU
HT45F77
Revision: V1.10
Date: ����������������
January 19, 2015
HT45F77
Body Fat Scale 8-Bit Flash MCU
Table of Contents
Features............................................................................................................. 7
CPU Features.......................................................................................................................... 7
Peripheral Features.................................................................................................................. 7
General Description.......................................................................................... 8
Block Diagram................................................................................................... 8
Pin Assignment................................................................................................. 9
Pin Description............................................................................................... 10
Absolute Maximum Ratings........................................................................... 13
D.C. Characteristics........................................................................................ 13
A.C. Characteristics........................................................................................ 16
LDO + PGA + ADC + VCM Electrical Characteristics................................... 17
Effective Number of Bits (ENOB)........................................................................................... 18
Operational Amplifier Electrical Characteristics (Body Fat Circuit).......... 19
LCD D.C. Characteristics............................................................................... 19
Power-on Reset Characteristics.................................................................... 19
System Architecture....................................................................................... 20
Clocking and Pipelining.......................................................................................................... 20
Program Counter.................................................................................................................... 21
Stack...................................................................................................................................... 22
Arithmetic and Logic Unit – ALU ........................................................................................... 22
Flash Program Memory.................................................................................. 23
Structure................................................................................................................................. 23
Special Vectors...................................................................................................................... 23
Look-up Table ........................................................................................................................ 23
Table Program Example......................................................................................................... 24
In Circuit Programming – ICP................................................................................................ 25
On Chip Debug Support – OCDS.......................................................................................... 26
In Application Programming – IAP......................................................................................... 26
RAM Data Memory.......................................................................................... 33
Structure ................................................................................................................................ 33
General Purpose Data Memory............................................................................................. 33
Special Purpose Data Memory.............................................................................................. 34
Special Function Register Description......................................................... 35
Indirect Addressing Registers – IAR0, IAR1, IAR2................................................................ 35
Memory Pointers – MP0, MP1L, MP1H, MP2L, MP2H.......................................................... 35
Accumulator – ACC................................................................................................................ 37
Program Counter Low Register – PCL................................................................................... 37
Look-up Table Registers – TBLP, TBHP, TBLH...................................................................... 37
Status Register – STATUS .................................................................................................... 37
Rev. 1.10
2
January 19, 2015
HT45F77
Body Fat Scale 8-Bit Flash MCU
EEPROM Data Memory................................................................................... 39
EEPROM Data Memory Structure......................................................................................... 39
EEPROM Registers............................................................................................................... 39
Reading Data from the EEPROM.......................................................................................... 41
Writing Data to the EEPROM................................................................................................. 41
Write Protection...................................................................................................................... 41
EEPROM Interrupt................................................................................................................. 41
Programming Considerations................................................................................................. 42
Oscillators....................................................................................................... 43
Oscillator Overview ............................................................................................................... 43
System Clock Configurations................................................................................................. 43
External Crystal/Ceramic Oscillator – HXT............................................................................ 44
Internal RC Oscillator – HIRC................................................................................................ 45
Internal 32kHz Oscillator – LIRC............................................................................................ 45
External 32.768kHz Crystal Oscillator – LXT......................................................................... 45
Supplementary Oscillators..................................................................................................... 47
Operating Modes and System Clocks.......................................................... 47
System Clocks....................................................................................................................... 47
System Operation Modes ...................................................................................................... 49
Control Register..................................................................................................................... 50
Fast Wake-up......................................................................................................................... 52
Operating Mode Switching .................................................................................................... 53
Standby Current Considerations ........................................................................................... 57
Wake-up ................................................................................................................................ 58
Programming Considerations................................................................................................. 58
Watchdog Timer.............................................................................................. 59
Watchdog Timer Clock Source............................................................................................... 59
Watchdog Timer Control Register.......................................................................................... 59
Watchdog Timer Operation.................................................................................................... 60
Reset and Initialisation .................................................................................. 62
Reset Functions..................................................................................................................... 62
Reset Initial Conditions ......................................................................................................... 65
Input/Output Ports ......................................................................................... 69
I/O Register List..................................................................................................................... 69
Pull-high Resistors................................................................................................................. 69
Port A Wake-up...................................................................................................................... 71
I/O Port Control Registers...................................................................................................... 71
I/O Pin Structures................................................................................................................... 73
Programming Considerations ................................................................................................ 73
Rev. 1.10
3
January 19, 2015
HT45F77
Body Fat Scale 8-Bit Flash MCU
Timer Modules – TM....................................................................................... 74
Introduction............................................................................................................................ 74
TM Operation......................................................................................................................... 74
TM Clock Source.................................................................................................................... 74
TM Interrupts.......................................................................................................................... 75
TM External Pins ................................................................................................................... 75
TM Input/Output Pin Control Registers.................................................................................. 75
Programming Considerations................................................................................................. 76
Compact Type TM – CTM............................................................................... 77
Compact TM Operation ......................................................................................................... 77
Compact Type TM Register Description................................................................................ 78
Compact Type TM Operating Modes .................................................................................... 82
Periodic Type TM – PTM................................................................................. 88
Periodic TM Operation........................................................................................................... 88
Periodic Type TM Register Description.................................................................................. 89
Periodic Type TM Operating Modes....................................................................................... 93
Internal Power Supply ................................................................................. 102
Analog to Digital Converter – ADC.............................................................. 104
A/D Data Rate Definition...................................................................................................... 104
A/D Overview....................................................................................................................... 104
A/D Converter Register Description..................................................................................... 105
Programmable Gain Amplifier – PGA................................................................................... 105
A/D Converter Data Registers – ADRL, ADRM, ADRH........................................................ 107
A/D Converter Control Registers – ADCR0, ADCR1, ADCS................................................ 108
A/D Operation.......................................................................................................................110
Summary of A/D Conversion Steps.......................................................................................111
Programming Considerations................................................................................................112
A/D Transfer Function...........................................................................................................112
A/D Converted Data..............................................................................................................113
A/D Converted Data to Voltage.............................................................................................113
A/D Programming Example...................................................................................................114
Temperature Sensor......................................................................................115
Serial Interface Module – SIM.......................................................................115
SPI Interface ........................................................................................................................115
SPI Interface Operation ........................................................................................................115
SPI Registers........................................................................................................................116
SPI Communication .............................................................................................................119
I2C Interface......................................................................................................................... 121
I2C Interface Operation ........................................................................................................ 122
I2C Registers........................................................................................................................ 123
I2C Bus Communication....................................................................................................... 126
I2C Bus Start Signal.............................................................................................................. 127
I2C Slave Address................................................................................................................ 127
I2C Bus Read/Write Signal................................................................................................... 128
Rev. 1.10
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January 19, 2015
HT45F77
Body Fat Scale 8-Bit Flash MCU
I2C Bus Slave Address Acknowledge Signal........................................................................ 128
I2C Bus Data and Acknowledge Signal................................................................................ 128
I2C Time Out Function.......................................................................................................... 130
I2C Time Out Operation........................................................................................................ 130
UART Module Serial Interface with IR Carrier............................................ 131
UART Module Features....................................................................................................... 131
UART Module Overview....................................................................................................... 131
UART External Pin Interfacing............................................................................................. 131
UART Data Transfer Scheme.............................................................................................. 132
UART Status and Control Registers.................................................................................... 132
Baud Rate Generator........................................................................................................... 138
UART Setup and Control..................................................................................................... 139
Managing Receiver Errors................................................................................................... 143
UART Module Interrupt Structure......................................................................................... 144
UART Module Power Down and Wake-up........................................................................... 146
IR Modulation Interface........................................................................................................ 146
Interrupts....................................................................................................... 147
Interrupt Registers................................................................................................................ 147
Interrupt Operation............................................................................................................... 152
External Interrupt.................................................................................................................. 154
A/D Converter Interrupt........................................................................................................ 154
Multi-function Interrupt......................................................................................................... 154
Serial Interface Module Interrupt.......................................................................................... 155
Time Base Interrupts............................................................................................................ 155
I2C Time Out Interrupt.......................................................................................................... 156
UART Interrupt..................................................................................................................... 157
EEPROM Interrupt............................................................................................................... 157
LVD Interrupt........................................................................................................................ 157
TM Interrupts........................................................................................................................ 157
Interrupt Wake-up Function.................................................................................................. 158
Programming Considerations............................................................................................... 158
Low Voltage Detector – LVD........................................................................ 159
LVD Register........................................................................................................................ 159
LVD Operation...................................................................................................................... 160
LCD Driver..................................................................................................... 161
LCD Display Memory........................................................................................................... 163
Clock Source ....................................................................................................................... 163
LCD Registers...................................................................................................................... 164
LCD Driver Output................................................................................................................ 166
LCD Voltage Source and Biasing......................................................................................... 167
LCD Waveform Timing Diagrams ........................................................................................ 168
Programming Considerations............................................................................................... 170
Rev. 1.10
5
January 19, 2015
HT45F77
Body Fat Scale 8-Bit Flash MCU
Body Fat Measurement Function................................................................ 171
Sine Wave Generator........................................................................................................... 171
Amplifier............................................................................................................................... 174
Filter..................................................................................................................................... 175
Configuration Option.................................................................................... 176
Application Circuit........................................................................................ 177
Instruction Set............................................................................................... 178
Introduction.......................................................................................................................... 178
Instruction Timing................................................................................................................. 178
Moving and Transferring Data.............................................................................................. 178
Arithmetic Operations........................................................................................................... 178
Logical and Rotate Operation.............................................................................................. 179
Branches and Control Transfer............................................................................................ 179
Bit Operations...................................................................................................................... 179
Table Read Operations........................................................................................................ 179
Other Operations.................................................................................................................. 179
Instruction Set Summary............................................................................. 180
Table Conventions................................................................................................................ 180
Extended Instruction Set...................................................................................................... 182
Instruction Definition.................................................................................... 184
Extended Instruction Definition............................................................................................ 193
Package Information.................................................................................... 200
64-pin LQFP (7mm × 7mm) Outline Dimensions................................................................. 201
80-pin LQFP (10mm × 10mm) Outline Dimensions............................................................. 202
Rev. 1.10
6
January 19, 2015
HT45F77
Body Fat Scale 8-Bit Flash MCU
Features
CPU Features
• Operating voltage
♦♦
fSYS=8MHz: 2.2V~5.5V
♦♦
fSYS=12MHz: 2.7V~5.5V
♦♦
fSYS=20MHz: 4.5V~5.5V
• Up to 0.2μs instruction cycle with 20MHz system clock at VDD=5V
• Power down and wake-up functions to reduce power consumption
• Four oscillators
♦♦
External Crystal − HXT
♦♦
External 32.768kHz Crystal − LXT
♦♦
Internal RC − HIRC
♦♦
Internal 32kHz RC − LIRC
• Multi-mode operation: NORMAL, SLOW, IDLE and SLEEP
• Fully integrated internal 4.8MHz, 4.8×2MHz and 4.8×3MHz oscillator requires no external
components
• All instructions executed in 1~3 instruction cycles
• Table read instructions
• 115 powerful instructionsl
• 8-level subroutine nesting
• Bit manipulation instruction
Peripheral Features
• Flash Program Memory: 8K×16
• RAM Data Memory: 256×8
• EEPROM Memory: 64×8
• Watchdog Timer function
• LCD COM driver with 1/3 bias
• 36 bidirectional I/O lines
• Dual pin-shared external interrupts
• Multiple Timer Modules for time measure, input capture, compare match output, PWM output or
single pulse output function
• Dual Time-Base functions for generation of fixed time interrupt signals
• 2 differential channels 20-bit resolution Delta-Sigma A/D converter
• Low voltage reset function
• Low voltage detect function
• Internal LDO with bypass function for PGA, ADC or external sensor power supply
• Serial Interfaces Module − SIM for SPI or I2C
• UART with IR carrier
• Body Fat circuit
• Package type: 64/80-pin LQFP
Rev. 1.10
7
January 19, 2015
HT45F77
Body Fat Scale 8-Bit Flash MCU
General Description
This Holtek device is specifically designed for Body Fat Scale applications. Measuring body fat uses
a technique whereby an AC current flowing through the human body is measured and then used to
calculate a body fat value. The specialised circuits to do this are a weight measurement circuit and a fat
measurement circuit. The weight measurement circuit uses an external load cell to output a signal, which
after amplification by an OPA, and then conversion using an ADC, reads the corresponding value as the
calculated weight. The fat measurement circuit uses an AC signal via an electrode slice to flow through
human body. After amplification by an internal OPA, and then conversion by an ADC, the measured
value is one representing body impedance, which is used to calculate the corresponding body fat value.
The device is a Flash Memory A/D type 8-bit high performance RISC architecture microcontroller
with multi-channel 20-bit Delta-Sigma A/D (ΔΣA/D) converter, designed for applications that interface
directly to analog signals and which require the low noise and high accuracy analog to digital converter.
Offering users the convenience of Flash Memory multi-programming features, this device also includes
a wide range of functions and features. Other memory includes an area of RAM Data Memory as well as
an area of EEPROM memory for storage of non-volatile data such as serial numbers, calibration data etc.
Analog features include a multi-channel with 20-bit ΔΣA/D converter and programmable gain
amplifier (PGA) functions. An extremely flexible Timer Module provides timing, pulse generation
and PWM generation functions. In addition, internal LDO function provides various power options
to the internal and external devices. 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.
A full choice of HXT, LXT, HIRC and LIRC oscillator functions are provided including a fully
integrated system oscillator which requires no external components for its implementation. The ability
to operate and switch dynamically between a range of operating modes using different clock sources
gives users the ability to optimise microcontroller operation and minimise power consumption.
The inclusion of flexible I/O programming features, Time-Base functions along with many other
features ensure that the device will find excellent use in applications such as weight scales, electronic
metering, environmental monitoring, handheld instruments, household appliances, electronically
controlled tools, motor driving in addition to many others.
Block Diagram
Flash / EEPROM
P�og�amming Ci�c�it��
Flash
P�og�am
Memo��
EEPROM
Data
Memo��
Watchdog
Time�
Inte�nal
HIRC/LIRC
Oscillato�s
Low
Voltage
Detect
Low
Voltage
Reset
RAM
Data
Memo��
Reset
Ci�c�it
8-bit RISC
MCU Co�e
Inte���pt
Cont�olle�
Exte�nal
HXT/LXT
Oscillato�s
Time Bases
LDO + OP +
�0-bit A/D Conve�te�
I/O
Rev. 1.10
SIM
LCD
D�ive�
Time�
Mod�les
UART
8
Impedance
Meas��ement
January 19, 2015
HT45F77
Body Fat Scale 8-Bit Flash MCU
Pin Assignment
PC�/TP0_0/RX/SEG�
PC1/TP0_1/SDI/SDA/SEG1
PA7/TCK1/SDO/SEG0
PA6/TP1_0/SCS
PA�/TP1_1/SCK/SCL
PA4/TCK�
PA3/TP�_0/INT0
PA1/TP�_1/INT1
PA�/ICPCK/OCDSCK
PA0/ICPDA/OCDSDA
PB0
PB�/OSC�
PB1/OSC1
VSS
PB3/XT1
PB4/XT�
VDD
VIN
AVDD
AVSS
VCM
VREFP
VREFN
AN0
AN1
AN�
AN3
RFC
CP0N
TO
FVR
FIR
1
�
3
4
�
6
7
8
�
10
11
1�
13
14
1�
16
64 63 6� 61 60 �� �8 �7 �6 �� �4 �3 �� �1 �0 4�
48
47
46
4�
44
43
4�
HT45F77/HT45V77
41
64 LQFP-A
40
3�
38
37
36
3�
34
33
17 18 1� �0 �1 �� �3 �4 �� �6 �7 �8 �� 30 31 3�
PC3/TCK0/TX/SEG3
PE0/SEG16
PE1/SEG17
PE�/SEG18
PE3/SEG1�
PE4/SEG�0
PE�/SEG�1
PE6/SEG��
PE7/SEG�3
SEG�4
SEG��
SEG�6
SEG�7
SEG�8
SEG��
SEG30
SEG31
COM3
COM�
COM1
COM0
V�
V1
VMAX
C�
C1
PLCD
SIN
FVL
FIL
RF1
RF�
PC�/SEG�
PC4/SEG4
PC3/TCK0/TX/SEG3
PC�/TP0_0/RX/SEG�
PC1/TP0_1/SDI/SDA/SEG1
PA7/TCK1/SDO/SEG0
PA6/TP1_0/SCS
PA�/TP1_1/SCK/SCL
PA4/TCK�
PA3/TP�_0/INT0
PA1/TP�_1/INT1
PA�/ICPCK/OCDSCK
PA0/ICPDA/OCDSDA
PB0
PB�/OSC�
PB1/OSC1
VSS
PB3/XT1
PB4/XT�
VDD
VIN
AVDD
AVSS
VCM
VREFP
VREFN
AN0
AN1
AN�
AN3
RFC
CP0N
TO
FVR
FIR
RF�
RF1
FIL
FVL
SIN
80 7� 78 77 76 7� 74 73 7� 71 70 6� 68 67 66 6� 6463 6� 61
60
�
��
3
�8
4
�7
�
�6
6
��
7
�4
8
�3
�
��
HT45F77/HT45V77
10
�1
11
80 LQFP-A
40
1�
4�
13
48
14
47
1�
46
16
4�
17
44
18
43
1�
4�
�0
41
�1 �� �3 �4 �� �6 �7 �8 �� 30 31 3� 33 34 3� 36 3738 3� 40
1
PC6/SEG6
PC7/SEG7
PD0/SEG8
PD1/SEG�
PD�/SEG10
PD3/SEG11
PD4/SEG1�
PD�/SEG13
PD6/SEG14
PD7/SEG1�
PE0/SEG16
PE1/SEG17
PE�/SEG18
PE3/SEG1�
PE4/SEG�0
PE�/SEG�1
PE6/SEG��
PE7/SEG�3
SEG�4
SEG��
SEG�6
SEG�7
SEG�8
SEG��
SEG30
SEG31
SEG3�
SEG33
SEG34
SEG3�
COM3
COM�
COM1
COM0
V�
V1
VMAX
C�
C1
PLCD
Note: The OCDSDA and OCDSCK pins are the OCDS dedicated pins and only available for the HT45V77 device
which is the OCDS EV chip for the HT45F77 device.
Rev. 1.10
9
January 19, 2015
HT45F77
Body Fat Scale 8-Bit Flash MCU
Pin Description
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.
Pin Name
PA0/ICPDA/
OCDSDA
PA1/TP2_1/
INT1
PA2/ICPCK/
OCDSCK
PA3/TP2_0/
INT0
PA4/TCK2
PA5/TP1_1/
SCK/SCL
PA6/TP1_0/
SCS
PA7/TCK1/
SDO/SEG0
PB0
PB1/OSC1
PB2/OSC2
PB3/XT1
PB4/XT2
Rev. 1.10
Function
OPT
I/T
PA0
PAPU
PAWU
ST
O/T
Descriptions
CMOS General purpose I/O. Register enabled pull-up and wake-up.
ICPDA
—
ST
CMOS ICP address/data
OCDSDA
—
ST
CMOS OCDS address/data, for EV chip only.
PA1
PAPU
PAWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up.
TP2_1
CTRL0
PTM2C0
ST
CMOS TM2 input/output
INT1
INTC0
ST
PA2
PAPU
PAWU
ST
—
External Interrupt 1 input
CMOS General purpose I/O. Register enabled pull-up and wake-up.
ICPCK
—
ST
—
ICP clock
OCDSCK
—
ST
—
OCDS clock, for EV chip only.
PA3
PAPU
PAWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up.
TP2_0
CTRL0
PTM2C0
ST
CMOS TM2 input/output
INT0
INTC0
ST
PA4
PAPU
PAWU
ST
TCK2
PTM2C0
ST
PA5
PAPU
PAWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up.
TP1_1
CTRL0
PTM1C0
ST
CMOS TM1 input/output
—
External Interrupt 0 input
CMOS General purpose I/O. Register enabled pull-up and wake-up.
—
TM2 clock input
SCK
SIMC0
ST
CMOS SPI serial clock
SCL
SIMC0
ST
CMOS I2C clock line
PA6
PAPU
PAWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up.
TP1_0
CTRL0
PTM1C0
ST
CMOS TM1 input/output
SCS
SIMC0
ST
CMOS SPI slave select pin
PA7
PAPU
PAWU
ST
CMOS General purpose I/O. Register enabled pull-up and wake-up.
TCK1
PTM1C0
ST
SDO
SIMC0
—
—
TM1 clock input
CMOS SPI serial data output
SEG0
LCD1
—
CMOS LCD Segment output
PB0
PBPU
ST
CMOS General purpose I/O. Register enabled pull-up.
PB1
PBPU
ST
CMOS General purpose I/O. Register enabled pull-up.
OSC1
CO
HXT
PB2
PBPU
ST
OSC2
CO
—
PB3
PBPU
ST
XT1
CO
LXT
PB4
PBPU
ST
XT2
CO
—
—
HXT Oscillator input
CMOS General purpose I/O. Register enabled pull-up.
HXT
HXT Oscillator output
CMOS General purpose I/O. Register enabled pull-up.
—
LXT Oscillator input
CMOS General purpose I/O. Register enabled pull-up.
LXT
LXT Oscillator output
10
January 19, 2015
HT45F77
Body Fat Scale 8-Bit Flash MCU
Pin Name
PC1/TP0_1/
SDI/SDA/SEG1
PC2/TP0_0/RX/
SEG2
PC3/TCK0/
TX/SEG3
PC4/SEG4
PC5/SEG5
PC6/SEG6
PC7/SEG7
PD0/SEG8
PD1/SEG9
PD2/SEG10
PD3/SEG11
PD4/SEG12
PD5/SEG13
PD6/SEG14
PD7/SEG15
PE0/SEG16
PE1/SEG17
PE2/SEG18
PE3/SEG19
Rev. 1.10
Function
OPT
I/T
PC1
PCPU
ST
CMOS General purpose I/O. Register enabled pull-up.
O/T
TP0_1
CTRL0
TM0C0
ST
CMOS TM0 input/output
SDI
SIMC0
ST
SDA
SIMC0
ST
—
Descriptions
SPI serial data input
CMOS I2C data line
SEG1
LCD1
—
CMOS LCD Segment output
PC2
PCPU
ST
CMOS General purpose I/O. Register enabled pull-up.
TP0_0
CTRL0
TM0C0
ST
CMOS TM0 input/output
RX
UCR1
UCR2
ST
SEG2
LCD1
—
CMOS LCD Segment output
CMOS General purpose I/O. Register enabled pull-up.
—
UART receiver pin
PC3
PCPU
ST
TCK0
TM0C0
ST
TX
UCR1
UCR2
—
CMOS UART transceiver pin
SEG3
LCD1
—
CMOS LCD Segment output
CMOS General purpose I/O. Register enabled pull-up.
—
TM0 clock input
PC4
PCPU
ST
SEG4
LCD1
—
CMOS LCD Segment output
PC5
PCPU
ST
CMOS General purpose I/O. Register enabled pull-up.
SEG5
LCD1
—
CMOS LCD Segment output
PC6
PCPU
ST
CMOS General purpose I/O. Register enabled pull-up.
SEG6
LCD1
—
CMOS LCD Segment output
PC7
PCPU
ST
CMOS General purpose I/O. Register enabled pull-up.
SEG7
LCD1
—
CMOS LCD Segment output
CMOS General purpose I/O. Register enabled pull-up.
PD0
PDPU
ST
SEG8
LCD2
—
CMOS LCD Segment output
PD1
PDPU
ST
CMOS General purpose I/O. Register enabled pull-up.
SEG9
LCD2
—
CMOS LCD Segment output
PD2
PDPU
ST
CMOS General purpose I/O. Register enabled pull-up.
SEG10
LCD2
—
CMOS LCD Segment output
PD3
PDPU
ST
CMOS General purpose I/O. Register enabled pull-up.
SEG11
LCD2
—
CMOS LCD Segment output
PD4
PDPU
ST
CMOS General purpose I/O. Register enabled pull-up.
SEG12
LCD2
—
CMOS LCD Segment output
PD5
PDPU
ST
CMOS General purpose I/O. Register enabled pull-up.
SEG13
LCD2
—
CMOS LCD Segment output
PD6
PDPU
ST
CMOS General purpose I/O. Register enabled pull-up.
SEG14
LCD2
—
CMOS LCD Segment output
PD7
PDPU
ST
CMOS General purpose I/O. Register enabled pull-up.
SEG15
LCD2
—
CMOS LCD Segment output
PE0
PEPU
ST
CMOS General purpose I/O. Register enabled pull-up.
SEG16
LCD3
—
CMOS LCD Segment output
PE1
PEPU
ST
CMOS General purpose I/O. Register enabled pull-up.
SEG17
LCD3
—
CMOS LCD Segment output
PE2
PEPU
ST
CMOS General purpose I/O. Register enabled pull-up.
SEG18
LCD3
—
CMOS LCD Segment output
PE3
PEPU
ST
CMOS General purpose I/O. Register enabled pull-up.
SEG19
LCD3
—
CMOS LCD Segment output
11
January 19, 2015
HT45F77
Body Fat Scale 8-Bit Flash MCU
Pin Name
PE4/SEG20
PE5/SEG21
PE6/SEG22
PE7/SEG23
Function
OPT
I/T
PE4
PEPU
ST
O/T
Descriptions
CMOS General purpose I/O. Register enabled pull-up.
SEG20
LCD3
—
CMOS LCD Segment output
PE5
PEPU
ST
CMOS General purpose I/O. Register enabled pull-up.
SEG21
LCD3
—
CMOS LCD Segment output
PE6
PEPU
ST
CMOS General purpose I/O. Register enabled pull-up.
SEG22
LCD3
—
CMOS LCD Segment output
PE7
PEPU
ST
CMOS General purpose I/O. Register enabled pull-up.
SEG23
LCD3
—
CMOS LCD Segment output
SEG24~SEG35
SEGn
—
—
CMOS LCD Segment output
COM0~COM3
COMn
—
—
CMOS LCD Common output
V1
V1
—
—
—
LCD voltage pump
V2
V2
—
—
—
LCD voltage pump
C1
C1
—
—
—
LCD voltage pump
C2
C2
—
—
—
LCD voltage pump
VMAX
VMAX
—
PWR
—
LCD Power Selection
PLCD
PLCD
—
PWR
—
LCD Power
SIN
SIN
—
—
AO
Sine Wave Output
FVL
FVL
—
AI
AO
Left Foot Channel 1
FIL
FIL
—
AI
AO
Left Foot Channel 2
RF1
RF1
—
AI
AO
Reference 1 Impedance Channel
RF2
RF2
—
AI
AO
Reference 2 Impedance Channel
FIR
FIR
—
AI
AO
Right Foot Channel 2
FVR
FVR
—
AI
AO
Right Foot Channel 1
TO
—
—
AO
OPA Output
CP0N
—
AI
—
Peak Detector Input
RFC
RFC
—
AI
—
ADC Analog Input
VIN
VIN
—
PWR
—
LDO Input
AVDD
(VOUT)
—
PWR
—
Analog Power Supply (LDO Output)
AVSS
AVSS
—
PWR
—
Analog Ground
VCM
VCM
—
—
VERFP
VERFP
—
PWR
—
ADC Positive Reference Input (External)
VERFN
VERFN
—
PWR
—
ADC Negative Reference Input (External)
AN0~AN3
ANn
—
AI
—
ADC Input Channel 0~3
VDD
VDD
—
PWR
—
Digital Power supply
VSS
VSS
—
PWR
—
Digital Ground
TO
CP0N
AVDD(VOUT)
PWR ADC Internal Common Mode Voltage Output
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
AI: Analog input
AO: Analog output
HXT: High frequency crystal oscillator
LXT: Low frequency crystal oscillator
Rev. 1.10
12
January 19, 2015
HT45F77
Body Fat Scale 8-Bit Flash MCU
Absolute Maximum Ratings
Supply Voltage.................................................................................................VSS−0.3V to VSS+6.0V
Input Voltage...................................................................................................VSS−0.3V to VDD+0.3V
Storage Temperature.....................................................................................................-50˚C to 125˚C
Operating Temperature...................................................................................................-40˚C to 85˚C
IOL Total.................................................................................................................................... 150mA
IOH Total...................................................................................................................................-100mA
Total Power Dissipation.......................................................................................................... 500mW
Note: These are stress ratings only. Stresses exceeding the range specified under "Absolute Maximum
Ratings" may cause substantial damage to these devices. Functional operation of these devices at
other conditions beyond those listed in the specification is not implied and prolonged exposure to
extreme conditions may affect devices reliability.
D.C. Characteristics
Ta=25°C
Symbol
VDD1
VDD2
Parameter
Operating Voltage (HXT)
Operating Voltage (HIRC)
Test Conditions
Min.
Typ.
Max.
Unit
fSYS=8MHz
2.2
─
5.5
V
fSYS=12MHz
2.7
─
5.5
V
fSYS=16MHz
4.5
─
5.5
V
fSYS=4.8MHz
2.2
─
5.5
V
No load, fH=8MHz, LDO, charge pump,
LCD, ADC off, WDT enable
─
1.0
1.5
mA
─
2.5
4
mA
No load, fH=10MHz, LDO, charge pump,
LCD, ADC off, WDT enable
─
1.2
2.0
mA
─
2.8
4.5
mA
No load, fH=12MHz, LDO, charge pump,
LCD, ADC off, WDT enable
─
1.5
2.5
mA
─
3.5
5.5
mA
5V
No load, fH=16MHz, LDO, charge pump,
LCD, ADC off, WDT enable
─
4.5
7.0
mA
5V
No load, fH=20MHz, LDO, charge pump,
LCD, ADC off, WDT enable
─
5.5
8.5
mA
─
─
3V
5V
3V
IDD1
Operating Current
(HXT, fSYS=fH,
fS=fSUB=fLXT or fLIRC)
5V
3V
5V
3V
5V
IDD2
Operating Current
(HIRC, fSYS=fH,
fS=fSUB=fLXT or fLIRC)
3V
5V
3V
5V
Rev. 1.10
Conditions
VDD
No load, fH=4.8MHz, LDO, charge
pump, LCD, ADC off, WDT enable
─
0.7
1.2
mA
─
1.5
2.5
mA
No load, fH=4.8×2MHz, LDO, charge
pump, LCD, ADC off, WDT enable
─
1.2
2.0
mA
─
2.8
4.5
mA
No load, fH=4.8×3MHz, LDO, charge
pump, LCD, ADC off, WDT enable
─
1.8
3.0
mA
─
4.0
6.0
mA
13
January 19, 2015
HT45F77
Body Fat Scale 8-Bit Flash MCU
Symbol
Parameter
Test Conditions
3V
5V
3V
5V
3V
IDD3
Operating Current
(HXT, fSYS=fL,
fS=fSUB=fLXT or fLIRC)
5V
3V
5V
3V
5V
3V
5V
3V
IDD4
Operating Current
(LXT, fSYS= fSUB=fLXT,
fS=fSUB=fLXT)
5V
3V
5V
IDD5
Operating Current
(LIRC, fSYS= fSUB=fLIRC,
fS=fSUB=fLIRC)
3V
ISTB1
Standby Current (Idle)
(HXT, fSYS=fH,
fS=fSUB=fLXT or fLIRC)
3V
ISTB2
Standby Current (Idle)
(HXT, fSYS=off, fS=T1)
3V
ISTB3
Standby Current (Idle)
(HXT, fSYS=off,
fS=fSUB=fLXT or fLIRC)
3V
ISTB4
Standby Current (Idle)
(HIRC, fSYS=off,
fS=fSUB=fLIRC)
3V
ISTB5
Standby Current (Idle)
(HXT, fSYS=fL,
fS=fSUB=fLXT or fLIRC)
3V
ISTB6
Standby Current (Idle)
(HXT, fSYS=off,
fS=fSUB=fLXT or fLIRC)
3V
ISTB7
Standby Current (Idle)
(LXT, fSYS= fSUB=fLXT,
fS=fSUB=fLXT)
3V
ISTB8
Standby Current (Idle)
(LXT, fSYS=off, fS=T1)
ISTB9
Standby Current (Idle)
(LXT, fSYS=off,
fS=fSUB=fLXT)
Rev. 1.10
Conditions
VDD
5V
5V
5V
5V
5V
5V
5V
5V
3V
5V
3V
5V
Min.
Typ.
Max.
Unit
─
0.9
1.5
mA
─
2.1
3.3
mA
No load, fH=12MHz, fL=fH/4, LDO, charge
pump, LCD, ADC off, WDT enable
─
0.6
1.0
mA
─
1.6
2.5
mA
No load, fH=12MHz, fL=fH/8, LDO, charge
pump, LCD, ADC off, WDT enable
─
0.48
0.8
mA
─
1.2
2.0
mA
No load, fH=12MHz, fL=fH/16, LDO,
charge pump, ADC off, WDT enable
─
0.42
0.7
mA
─
1.1
1.7
mA
No load, fH=12MHz, fL=fH/32, LDO, charge
pump, LCD, ADC off, WDT enable
─
0.38
0.6
mA
─
1.0
1.5
mA
No load, fH=12MHz, fL=fH/64, LDO, charge
pump, LCD, ADC off, WDT enable
─
0.36
0.55
mA
─
1.0
1.5
mA
No load, LDO, charge pump, LCD, ADC
off, WDT enable, LXTLP=0
─
10
20
μA
─
30
50
μA
No load, LDO, charge pump, LCD, ADC
off, WDT enable, LXTLP =1
─
10
20
μA
─
30
50
μA
No load, LDO, charge pump, LCD, ADC
off, WDT enable
─
10
20
μA
─
30
50
μA
No load, system HALT, LDO, charge
pump, LCD, ADC off, WDT enable,
fSYS=12MHz
─
0.6
1.0
mA
─
1.2
2.0
mA
No load, system HALT, LDO, charge
pump, LCD, ADC off, WDT enable,
fSYS=12MHz
─
1.3
3.0
μA
─
2.2
5.0
μA
No load, system HALT, LDO, charge
pump, LCD, ADC off, WDT enable,
fSYS=12MHz
─
1.3
3.0
μA
─
2.2
5.0
μA
No load, system HALT, LDO, charge
pump, LCD, ADC off, WDT enable,
fSYS=4.8×3MHz
─
1.3
3.0
μA
─
2.2
5.0
μA
No load, system HALT, LDO, charge
pump, LCD, ADC off, WDT enable,
fSYS=12MHz/64
─
0.34
0.6
mA
─
0.85
1.2
mA
No load, system HALT, LDO, charge
pump, LCD, ADC off, WDT enable,
fSYS=12MHz/64
─
1.3
3.0
μA
─
2.2
5.0
μA
No load, system HALT, LDO, charge
pump, LCD, ADC off, WDT enable,
fSYS=32768Hz
─
1.9
4.0
μA
─
3.3
7.0
μA
No load, system HALT, LDO, charge
pump, LCD, ADC off, WDT enable,
fSYS=32768Hz
─
1.3
3.0
μA
─
2.2
5.0
μA
No load, system HALT, LDO, charge
pump, LCD, ADC off, WDT enable,
fSYS=32768Hz
─
1.3
3.0
μA
─
2..2
5.0
μA
No load, fH=12MHz, fL=fH/2, ADC off,
WDT enable
14
January 19, 2015
HT45F77
Body Fat Scale 8-Bit Flash MCU
Symbol
Parameter
Test Conditions
Min.
Typ.
Max.
Unit
No load, system HALT, LDO, charge
pump, LCD, ADC off, WDT enable,
fSYS=32kHz
─
1.3
3.0
μA
─
2.2
5.0
μA
No load, system HALT, LDO, charge
pump, LCD, ADC off, WDT disable,
fSYS=12MHz
─
0.1
1
μA
─
0.3
2
μA
No load, system HALT, LDO, charge
pump, LCD, ADC off, WDT enable,
fSYS=12MHz
─
1.3
5
μA
─
2.2
10
μA
No load, system HALT, LDO, charge
pump, ADC off, WDT enable,
fSYS=12MHz
─
1.3
5
μA
─
2.2
10
μA
No load, system HALT, LDO, charge
pump, ADC off, WDT enable,
fSYS=32768Hz
─
1.3
3.0
μA
Conditions
VDD
ISTB10
Standby Current (Idle)
(LIRC, fSYS=off,
fS=fSUB=fLIRC)
3V
ISTB11
Standby Current (Sleep)
(HXT, fSYS=off,
fS=fSUB=fLXT or fLIRC)
3V
ISTB12
Standby Current (Sleep)
(HXT, fSYS=off,
fS=fSUB=fLXT)
3V
ISTB13
Standby Current (Sleep)
(HXT, fSYS=off,
fS=fSUB=fLIRC)
3V
ISTB14
Standby Current (Sleep)
(LXT, fSYS=off,
fS=fSUB=fLXT)
3V
ISTB15
Standby Current (Sleep)
(HXT, fSYS=off,
fS=fSUB=fLXT or fLIRC)
VIL
Input Low Voltage for I/O
Ports, TCKn, TPn_0,
TPn_1 and INTn
VIH
Input High Voltage for I/O
Ports, TCKn, TPn_0,
TPn_1 and INTn
5V
5V
5V
5V
5V
─
2.2
5.0
μA
─
No load, system HALT, LDO, charge
pump, LCD, ADC off, WDT disable,
fSYS=12MHz, LVR enable and LVDEN=1
─
90
120
μA
─
─
0
─
0.2VDD
V
5V
─
0
─
1.5
V
─
─
0.8VDD
─
VDD
V
5V
─
3.5
─
5
V
VLVR1
LVR Enable, 2.1V option
2.1
VLVR2
LVR Enable, 2.55V option
2.55
VLVR3
Low Voltage Reset
Voltage
─
LVR Enable, 3.8V option
VLVR4
ILVR
LVR Enable, 3.15V option
-5%
Low Voltage Reset Current
─
LVR Enable, LVDEN=0
3.15
V
+5%
3.8
─
60
V
V
V
90
μA
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
LVDEN = 1, VLVD = 2.7V
2.7
VLVD5
Low Voltage Detector
Voltage
─
LVDEN = 1, VLVD = 3.0V
-5%
3.0
+5%
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
ILVD1
ILVD2
Low Voltage Detector
Current
IOL
I/O Port Sink Current
IOH
I/O Port Source Current
RPH
Rev. 1.10
Pull-high Resistance of
I/O Ports
─
LVR disable, LVDEN = 1
─
75
120
μA
LVR enable, LVDEN = 1
─
90
150
μA
─
VDD=3V, VOL=0.1VDD
4
8
─
mA
─
VDD=5V, VOL=0.1VDD
10
20
─
mA
─
VDD=3V, VOH=0.9VDD
-2
-4
─
mA
─
VDD=5V, VOH=0.9VDD
-5
-10
─
mA
3V
─
20
60
100
kΩ
5V
─
10
30
50
kΩ
15
January 19, 2015
HT45F77
Body Fat Scale 8-Bit Flash MCU
A.C. Characteristics
Ta=25°C
Symbol
Parameter
Test Conditions
VDD
Conditions
2.2~5.5V
fSYS1
System Clock (HXT)
2.7~5.5V
─
3.3~5.5V
4.5~5.5V
fSYS2
System Clock (HIRC)
fSYS3
System Clock (LXT)
fLIRC
System Clock (LIRC)
5V
Ta=25°C
─
─
5V
Ta=25°C
2.2V~5.5V Ta=-40°C~85°C
Min.
Typ.
Max.
Unit
0.4
─
8
MHz
0.4
─
10
MHz
0.4
─
12
MHz
0.4
─
16
MHz
-2%
4.8×2
+2%
MHz
─
32768
─
Hz
-10%
32
+10%
kHz
kHz
-50%
32
+60%
fSYS=HXT or LXT
─
1024
─
fSYS=HIRC
─
16
─
fSYS=LIRC
─
1~2
─
System Start-up Timer Period
(Wake-up from HALT)
─
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
tINT
Interrupt Pulse Width
─
─
10
─
─
μs
tSST
tRSTD
tSYS
tLVR
Low Voltage Width to Reset
─
─
120
240
480
μs
tLVD
Low Voltage Width to Interrupt
─
─
60
120
240
μs
tLVDS
LVDO Stable Time
─
For LVR enable,
LVD off → on
─
─
15
μs
─
For LVR disable,
LVD off → on
─
─
150
μs
tEERD
EEPROM Read Time
─
─
─
─
4
tSYS
tEEWR
EEPROM Write Time
─
─
1
2
4
ms
tTIMER
TCKn and Timer Capture Input Pulse
Width
─
─
0.3
─
─
μs
Note: tSYS = 1/fSYS
Rev. 1.10
16
January 19, 2015
HT45F77
Body Fat Scale 8-Bit Flash MCU
LDO + PGA + ADC + VCM Electrical Characteristics
Ta=25°C
Symbol
Parameter
Test Conditions
Conditions
VDD
Min.
Typ.
Max.
Unit
VIN
LDO Supply Voltage
─
─
2.7
─
5.5
V
IVOREG
LDO Operating Current
─
No load, LDOVS[1:0]=00
─
400
520
μA
─
LDOVS[1:0]=00
LDO Output Voltage
(IL=0.1mA, VIN>VOREG+0.2V)
─
LDOVS[1:0]=01
─
LDOVS[1:0]=10
+5%
V
─
LDOVS[1:0]=11
─
LDOVS[1:0]=00
─
─
100
─
LDOVS[1:0]=01
─
─
130
─
LDOVS[1:0]=10
─
─
180
─
LDOVS[1:0]=11
─
─
200
─
Ta=-40°C~85°C
─
─
30
Ppm/
°C
-0.3
─
+0.3
%/V
─
25
50
mV
VCMS=0, AVDD=3.3V,
No load
-5%
1.05
+5%
V
VCMS=1, AVDD=3.3V,
No load
-5%
1.25
+5%
V
IL=200μA
0.98
–
1.02
V
VOREG
Dropout Voltage
(IL=10mA)
Temperature
Drift
LDOVS[1:0]=00b
VOREG Voltage IL=100μA
Drift
ΔVLOAD
Load Regulation
VCM Output Voltage
2.7V~
5.5V
2.7V
─
VCM
─
Load =0mA~10mA,
MCU HALT, LDO=2.4V,
LDO enable, Other
function disable
2.4
-5%
2.6
2.9
3.3
mV
Temperature Drift
─
IL=10μA, Ta=-40°C~85°C
─
─
200
Ppm/
°C
AVDD Voltage Drift
─
No load,
AVDD=2.4V~3.3V
─
100
─
µV/V
tVCM
VCM Turn on Stable Time
─
10
─
─
ms
ICMSRC
VCM Source Current
─
VCM drop 2% of VCM
1
─
─
mA
ICMSNK
VCM Sink Current
─
VCM raise 2% of VCM
1
─
─
mA
2.4
─
3.3
V
VCM enable, VRBUFP=1
and VRBUFN=1
─
─
900
VCM enable, VRBUFP=0
and VRBUFN=0
─
600
750
VCM disable, VRBUFP=0
and VRBUFN=0
─
500
650
System HALT, no load
─
─
1
μA
─
─
20
Bit
─
ADC & ADC Internal Reference Voltage (Delta-Sigma ADC)
AVDD
ICM+IPGA+
IADC
Supply Voltage for VCM, ADC,
PGA
Operating Current for VCM, PGA
and ADC
─
─
─
μA
IADSTB
Standby Current
─
RSAD
ADC Resolution
─
NNFC
Noise Free Code
─
PGA Gain=128
Data Rate=10Hz
─
15.4
─
Bit
ENOB
Effective Number of Bits
─
PGA Gain=128
Data Rate=10Hz
─
18.1
─
Bit
fAD
A/D Clock Frequency (fMCLK)
─
─
4.8
─
MHz
Rev. 1.10
─
─
17
January 19, 2015
HT45F77
Body Fat Scale 8-Bit Flash MCU
Symbol
fADO
Test Conditions
Parameter
ADC Output Data Rate
─
VREF+
VREF-
Min.
Typ.
Max.
fMCLK=4.8MHz
FLMS[2:0]=000, ADC
CLK=fMCLK/30
5
─
625
fMCLK=4.8MHz
FLMS[2:0]=010, ADC
CLK=fMCLK/12
12
─
Conditions
VDD
Reference Input Voltage
VREF
Unit
Hz
1563
─
VREFS=1, VRBUFP=0
and VRBUFN=0
0.96
1.25
2.20
0
0
1.00
─
VREF= (VREF+) - (VREF-)
0.96
1.25
1.44
0.4
V
PGA
VDI+, VDI-
Absolute/Common Input Voltage
─
─
Gain = PGS×AGS
─
AVDD-1.1
V
ΔVR/Gain
─
ΔVR+
/Gain
V
ΔDI±
Differential Input Voltage Range
─
TCPGA
Gain Temperature Drift
─
Ta=-40°C~85°C
─
5
─
Ppm/
°C
─
Ta=-40°C~85°C
ΔVR=1.25V, VGS[1:0]=00
(Gain=1), VRBUFP=0 and
VRBUFN=0
─
175
─
μV/
°C
Temperature Sensor
Sensor Temperature Drift
TCS
Effective Number of Bits (ENOB)
AVDD=3.3V, VREF=1.25V, fMCLK=4.8MHz, FLMS[2:0]=000
PGA Gain
DATA RATE
(SPS)
1
2
4
8
16
32
64
128
18.6
5
19.7
19.8
19.6
19.7
19.7
19.6
19.2
10
19.4
19.3
19.3
19.3
19.3
19.1
18.7
18.1
20
19.0
18.8
18.7
18.9
18.8
18.6
18.2
17.5
39
18.4
18.3
18.3
18.3
18.3
18.1
17.7
17.0
78
18.1
17.9
18.0
17.9
17.9
17.6
17.2
16.5
156
17.6
17.4
17.4
17.4
17.3
17.1
16.6
15.9
313
15.8
15.8
15.9
15.8
15.9
15.9
15.8
15.3
625
14.1
14.0
14.0
14.1
14.1
14.0
14.1
14.4
AVDD=3.3V, VREF=1.25V, fMCLK=4.8MHz, FLMS[2:0]=010
PGA Gain
DATA RATE
(SPS)
1
2
4
8
16
32
64
128
12
19.4
18.8
18.7
18.8
18.8
18.7
18.9
18.1
24
19.0
18.3
18.3
18.3
18.3
18.2
17.9
17.3
49
18.5
17.8
17.8
17.8
17.9
17.7
17.4
16.8
98
18.2
18.2
18.1
18.2
18.1
17.8
17.2
16.4
195
17.9
17.8
17.8
17.8
17.6
17.3
16.7
15.9
391
17.4
17.2
17.2
17.2
17.1
16.8
16.2
15.4
781
16.2
16.1
16.1
16.1
16.1
15.9
15.5
14.8
1563
14.5
14.5
14.5
14.4
14.5
14.5
14.3
14.0
Rev. 1.10
18
January 19, 2015
HT45F77
Body Fat Scale 8-Bit Flash MCU
Operational Amplifier Electrical Characteristics (Body Fat Circuit)
Ta=25°C
Symbol
Parameter
Test Conditions
Min.
Conditions
VDD
─
Typ.
Max.
Unit
VDD
Supply Voltage
─
2.2
─
5.5
V
Icc
Supply Current Per Signal Amplifier
5V
Io = 0A
150
360
500
μA
SR
Slew Rate at Unity Gain
3V
RL = 100kΩ, CL = 100pF
7.5
─
─
V/µs
GBW
Gain Bandwidth Product
3V
RL = 100kΩ, CL = 100pF
─
─
2
MHz
SR
Slew Rate at Unity Gain
3V
RL = 100kΩ, CL = 100pF
7.5
─
─
V/µs
GBW
Gain Bandwidth Product
3V
RL = 100kΩ, CL = 100pF
─
─
5
MHz
OP0, OP2
OP1
LCD D.C. Characteristics
Ta=25°C
Symbol
Parameter
Test Conditions
Conditions
VDD
ILCDOL
LCD common and segment Sink
Current
3V
ILCDOH
LCD common and segment
Source Current
3V
VOL=0.1VDD
5V
VOH=0.9VDD
5V
Min.
Typ.
Max.
Unit
210
420
─
μA
350
700
─
μA
-80
-160
─
μA
-180
-360
─
μA
Power-on Reset Characteristics
Ta=25°C
Symbol
Test Conditions
Parameter
VDD
Conditions
Min.
Typ.
Max.
Unit
VPOR
VDD Start Voltage to Ensure Power-on Reset
—
—
—
—
100
mV
RRVDD
VDD Raising Rate to Ensure Power-on Reset
—
—
0.035
—
—
V/ms
tPOR
Minimum Time for VDD Stays at VPOR to
Ensure Power-on Reset
—
—
1
—
—
ms
Rev. 1.10
19
January 19, 2015
HT45F77
Body Fat Scale 8-Bit Flash MCU
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 the device 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 or two cycles for
most of the standard or extended instructions respectively, with the exception of branch or call
instructions which need one more cycle. An 8-bit wide ALU is used in practically all instruction set
operations, which carries out arithmetic operations, logic operations, rotation, increment, decrement,
branch decisions, etc. The internal data path is simplified by moving data through the Accumulator
and the ALU. Certain internal registers are implemented in the Data Memory and can be directly
or indirectly addressed. The simple addressing methods of these registers along with additional
architectural features ensure that a minimum of external components is required to provide a
functional I/O and A/D control system with maximum reliability and flexibility. This makes the
device suitable for low-cost, high-volume production for controller applications.
Clocking and Pipelining
The main system clock, derived from either a HXT, LXT, HIRC or LIRC oscillator is subdivided
into four internally generated non-overlapping clocks, T1~T4. 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.
   
 
  
System Clocking and Pipelining
Rev. 1.10
20
January 19, 2015
HT45F77
Body Fat Scale 8-Bit Flash MCU
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.
     
  
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 ex­
ecuted except for instructions, such as "JMP" or "CALL" that demands a jump to a non-consecutive
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.
Program Counter
Program Counter High Byte
PCL Register
PC12~PC8
PCL7~PCL0
Program Counter
The lower byte of the Program Counter, known as the Program Counter Low register or PCL, is
available for program control and is a readable and writeable register. By transferring data directly
into this register, a short program jump can be executed directly, however, as only this low byte
is available for manipulation, the jumps are limited to the present page of memory, that 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. 1.10
21
January 19, 2015
HT45F77
Body Fat Scale 8-Bit Flash MCU
Stack
This is a special part of the memory which is used to save the contents of the Program Counter
only. The stack is organized into 8 levels and 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
S ta c k L e v e l 3
o f S ta c k
P ro g ra m
M e m o ry
S ta c k L e v e l 8
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, LADD,
LADDM, LADC, LADCM, LSUB, LSUBM, LSBC, LSBCM, LDAA
• Logic operations: AND, OR, XOR, ANDM, ORM, XORM, CPL, CPLA, LAND, LANDM,
LOR, LORM, LXOR, LXORM, LCPL, LCPLA
• Rotation RRA, RR, RRCA, RRC, RLA, RL, RLCA, RLC, LRR, LRRA, LRRCA, LRRC, LRLA,
LRL, LRLCA, LRLC
• Increment and Decrement INCA, INC, DECA, DEC, LINCA, LINC, LDECA, LDEC
• Branch decision, JMP, SZ, SZA, SNZ, SIZ, SDZ, SIZA, SDZA, CALL, RET, RETI, LSNZ, LSZ,
LSZA, LSIZ, LSIZ, LSDZ, LSDZA
Rev. 1.10
22
January 19, 2015
HT45F77
Body Fat Scale 8-Bit Flash MCU
Flash Program Memory
The Program Memory is the location where the user code or program is stored. For this device 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 8K×16 bits. The Program Memory is addressed by the
Program Counter and also contains data, table information and interrupt entries. Table data, which can
be setup in any location within the Program Memory, is addressed by a separate table pointer register.
Reset
0000H
0004H
00�4H
Inte���pt
Vecto�
16 bits
1FFFH
Program Memory Structure
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.
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 corresponding table read instruction such as "TABRD [m]" or "TABRDL [m]" respectively when
the memory [m] is located in sector 0. If the memory [m] is located in other sectors, the data can be
retrieved from the program memory using the corresponding extended table read instruction such as
"LTABRD [m]" or "LTABRDL [m]" 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.
The accompanying diagram illustrates the addressing data flow of the look-up table.
A d d re s s
L a s t p a g e o r
T B H P R e g is te r
T B L P R e g is te r
Rev. 1.10
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
23
January 19, 2015
HT45F77
Body Fat Scale 8-Bit Flash MCU
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 microcontroller. 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 specified by TBLP and
TBHP if the "TABRD [m]" or "LTABRD [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]" or "LTABRD [m]" instruction is executed.
Because the TBLH register is read/write register and can 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.
Table Read Program Example
tempreg1 db ? ; temporary register #1
tempreg2 db ? ; temporary register #2
:
:
mov a,06h ; initialise low table pointer - note that this address is referenced
mov tblp,a ; to the last page or the page that tbhp pointed
mov a,1Fh ; initialise high table pointer
mov tbhp,a
:
:
tabrd tempreg1 ; transfers value in table referenced by table pointer data at program
; memory address "1F06H" transferred to tempreg1 and TBLH
dec tblp ; reduce value of table pointer by one
tabrd tempreg2 ; transfers value in table referenced by table pointer
; data at program memory address "1F05H" transferred to
; tempreg2 and TBLH in this example the data "1AH" is
; transferred to tempreg1 and data "1FH" to register tempreg2
:
:
org 1F00h ; sets initial address of program memory
dc 00Ah, 00Bh, 00Ch, 00Dh, 00Eh, 00Fh, 01Ah, 01Bh
:
:
Rev. 1.10
24
January 19, 2015
HT45F77
Body Fat Scale 8-Bit Flash MCU
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 in-circuit 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 re-insertion of the device.
The Holtek Flash MCU to Writer Programming Pin correspondence table is as follows:
Holtek Writer Pins
MCU Programming Pins
ICPDA
PA0
Programming Serial Data/Address
Pin Description
ICPCK
PA2
Programming Clock
VDD
VDD
Power Supply
VSS
VSS
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. The technical details regarding the in-circuit
programming of the device are beyond the scope of this document and will be supplied in
supplementary literature.
During the programming process, taking control of the PA0 and PA2 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.
W r ite r C o n n e c to r
S ig n a ls
M C U
W r ite r _ V D D
V D D
IC P D A
P A 0
IC P C K
P A 2
W r ite r _ V S S
V S S
*
P r o g r a m m in g
P in s
*
T o o th e r C ir c u it
Note: * may be resistor or capacitor. The resistance of * must be greater than 1k or the capacitance
of * must be less than 1nF.
Rev. 1.10
25
January 19, 2015
HT45F77
Body Fat Scale 8-Bit Flash MCU
On Chip Debug Support – OCDS
There is an EV chip named HT45V77 which is used to emulate the HT45F77 device. The EV
chip device also provides an "On-Chip Debug" function to debug the real MCU device during the
development process. The EV chip and the real MCU device are almost functionally compatible
except for "On-Chip Debug" function. Users can use the EV chip device to emulate the real chip
device behavior by connecting the OCDSDA and OCDSCK pins to the Holtek HT-IDE development
tools. The OCDSDA pin is the OCDS Data/Address input/output pin while the OCDSCK pin is
the OCDS clock input pin. When users use the EV chip for debugging, other functions which are
shared with the OCDSDA and OCDSCK pins in the device will have no effect in the EV chip.
However, the two OCDS pins which are pin-shared with the ICP programming pins are still used
as the Flash Memory programming pins for ICP. 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
VDD
VDD
Power Supply
VSS
VSS
Ground
On-Chip Debug Support Clock input
In Application Programming – IAP
The device offers IAP function to update data or application program to Flash ROM. Users can
define any ROM location for IAP, but there are some features which user must notice in using IAP
function.
• Erase page: 32 words/page
• Writing: 32 words/time
• Reading: 1 word/time
In Application Programming Control Register
The Address registers, FARL and FARH, and the Data registers, FD0L/FD0H, FD1L/FD1H, FD2L/
FD2H, FD3L/FD3H, located in all Data Memory sectors, together with the Control registers, FC0,
FC1 and FC2, located in Data Memory sector 1 are the corresponding Flash access registers for
IAP. As indirect addressing is the only way to access the FC0, FC1 and FC2 registers, all read and
write operations to the registers must be performed using the Indirect Addressing Register, IAR1 or
IAR2, and the Memory Pointer pair, MP1L/MP1H or MP2L/MP2H. Because the FC0, FC1 and FC2
control registers are located at the address of 28H~2AH in Data Memory sector 1, the desired value
ranged from 28H to 2AH must be written into the MP1L or MP2L Memory Pointer low byte and the
value "01H" must also be written into the MP1H or MP2H Memory Pointer high byte.
Rev. 1.10
26
January 19, 2015
HT45F77
Body Fat Scale 8-Bit Flash MCU
FC0 Register
Bit
7
6
5
4
3
2
1
0
Name
CFWEN
FMOD2
FMOD1
FMOD0
FWPEN
FWT
FRDEN
FRD
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
1
1
1
0
0
0
0
Bit 7CFWEN: Flash Memory Write enable control
0: Flash memory write function is disabled
1: Flash memory write function has been successfully enabled
When this bit is cleared to 0 by application program, the Flash memory write function
is disabled. Note that writing a "1" into this bit results in no action. This bit is used
to indicate that the Flash memory write function status. When this bit is set to 1 by
hardware, it means that the Flash memory write function is enabled successfully.
Otherwise, the Flash memory write function is disabled as the bit content is zero.
Bit 6~4FMOD2~FMOD0: Mode selection
000: Write program memory
001: Page erase program memory
010: Reserved
011: Read program memory
100: Reserved
101: Reserved
110: FWRN mode – Flash memory write function enable mode
111: Reserved
Bit 3FWPEN: Flash Memory Write procedure enable control
0: Disable
1: Enable
When this bit is set to 1 and the FMOD field is set to "110", the IAP controller will
execute the "Flash memory write function enable" procedure. Once the Flash memory
write function is successfully enabled, it is not necessary to set the FWPEN bit any
more.
Bit 2FWT: Flash ROM write control bit
0: Do not initiate Flash memory write or Flash memory write process is completed
1: Initiate Flash memory write process
This bit is set by software and cleared by hardware when the Flash memory write
process is completed.
Bit 1FRDEN: Flash memory read enabled bit
0: Flash memory read disable
1: Flash memory read enable
Bit 0FRD: Flash memory read control bit
0: Do not initiate Flash memory read or Flash memory read process is completed
1: Initiate Flash memory read process
This bit is set by software and cleared by hardware when the Flash memory read
process is completed.
FC1 Register
Bit
7
6
5
4
3
2
1
0
Name
D7
D6
D5
D4
D3
D2
D1
D0
R/W
R
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
0
0
0
0
0
0
0
Bit 7~055H: whole chip reset
When user writes 55H to this register, it will generate a reset signal to reset whole chip.
Rev. 1.10
27
January 19, 2015
HT45F77
Body Fat Scale 8-Bit Flash MCU
FC2 Register
Bit
7
6
5
4
3
2
1
0
Name
—
—
—
—
—
—
—
CLWB
R/W
—
—
—
—
—
—
—
R/W
POR
—
—
—
—
—
—
—
0
Bit 7~1
Unimplemented, read as "0"
Bit 0CLWB: Flash Memory Write buffer clear control
0: Do not initiate Write Buffer Clear or Write Buffer Clear process is completed
1: Initiate Write Buffer Clear process
This bit is set by software and cleared by hardware when the Write Buffer Clear
process is completed.
FARL Register
Bit
7
6
5
4
3
2
1
0
Name
A7
A6
A5
A4
A3
A2
A1
A0
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
Flash Memory Address [7:0]
FARH Register
Bit
7
6
5
4
3
2
1
0
Name
A15
A14
A13
A12
A11
A10
A9
A8
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
4
3
2
1
0
Bit 7~0
Flash Memory Address [15:8]
FD0L Register
Bit
7
6
5
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
The first Flash Memory data [7:0]
FD0H 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
Rev. 1.10
The first Flash Memory data [15:8]
28
January 19, 2015
HT45F77
Body Fat Scale 8-Bit Flash MCU
FD1L 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
3
2
1
0
Bit 7~0
The second Flash Memory data [7:0]
FD1H Register
Bit
7
6
5
4
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
3
2
1
0
Bit 7~0
The second Flash Memory data [15:8]
FD2L Register
Bit
7
6
5
4
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
The third Flash Memory data [7:0]
FD2H 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
3
2
1
0
Bit 7~0
The third Flash Memory data [15:8]
FD3L Register
Bit
7
6
5
4
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
The fourth Flash Memory data [7:0]
FD3H 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
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The fourth Flash Memory data [15:8]
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Flash Memory Write Function Enable Procedure
In order to allow users to change the Flash memory data through the IAP control registers, users
must first enable the Flash memory write operation by the following procedure:
• Write "110" into the FMOD2~FMOD0 bits to select the FWEN mode.
• Set the FWPEN bit to "1". The step 1 and step 2 can be executed simultaneously.
• The pattern data with a sequence of 00H, 04H, 0DH, 09H, C3H and 40H must be written into the
FD1L, FD1H, FD2L, FD2H, FD3L and FD3H registers respectively.
• A counter with a time-out period of 300μs will be activated to allow users writing the correct
pattern data into the FD1L/FD1H~FD3L/FD3H register pairs. The counter clock is derived from
LIRC oscillator.
• If the counter overflows or the pattern data is incorrect, the Flash memory write operation will
not be enabled and users must again repeat the above procedure. Then the FWPEN bit will
automatically be cleared to 0 by hardware.
• If the pattern data is correct before the counter overflows, the Flash memory write operation will
be enabled and the FPWEN bit will automatically be cleared to 0 by hardware. The CFWEN bit
will also be set to 1 by hardware to indicate that the Flash memory write operation is successfully
enabled.
• Once the Flash memory write operation is enabled, the user can change the Flash ROM data
through the Flash control register.
• To disable the Flash memory write operation, the user can clear the CFWEN bit to 0.
Is pattern is
correct ?
no
yes
Flash Memory
Write Function
Enable Procedure
Is counter
overflow ?
Set FMOD [2:0] =110 & FWPEN=1
→ Select FWEN mode & Start Flash write
Hardware activate a counter
yes
FWPEN=0
&
CFWEN=0
no
no
Wrtie the following pattern to Flash Data registers
FD1L= 00h , FD1H = 04h
FD2L= 0Dh , FD2H = 09h
FD3L= C3h , FD3H = 40h
FWPEN=0 ?
Failed
yes
CFWEN = 1
Success
END
Flash Memory Write Function Enable Procedure
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Body Fat Scale 8-Bit Flash MCU
Write
Flash Memory
Flash Memory
Write Function
Enable Procedure
Set Page Erase address: FARH/FARL
Set FMOD [2:0]=001 & FWT=1
→ Select “Page Erase mode”
& Initiate write operation
no
FWT=0 ?
yes
Set FMOD [2:0]=000
→ Select “Write Flash Mode”
Set Page Erase address: FARH/FARL
Write data to data register:
FD0L/FD0H
no
Page data
write finish ?
yes
Set FWT=1
no
FWT=0 ?
yes
Write Finish ?
no
yes
Clear CFWEN=0
END
Write Flash Memory Procedure
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ERASE PAGE
FARH
FARL[7:5]
0
0000 0000
000
1
0000 0000
001
2
0000 0000
010
3
0000 0000
011
4
0000 0000
100
5
0000 0000
101
110
6
0000 0000
7
0000 0000
111
8
0000 0001
000
9
0000 0001
001
:
:
:
252
0001 1111
100
253
0001 1111
101
254
0001 1111
110
255
0001 1111
111
Note
FARL[4:0]: don’t care
Read
Flash Memory
Set FMOD [2:0]=011
& FRDEN=1
Set Flash Address registers
FARH=xxh, FARL=xxh
Set FRD=1
No
FRD=0 ?
Yes
Read data value:
FD0L=xxh, FD0H=xxh
No
Read Finish ?
Yes
Clear FRDEN bit
END
Read Flash Memory Procedure
Note: When the FWT or FRD bit is set to 1, the MCU is stopped.
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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.
Divided into four types, the first of these is an area of RAM where special function registers are
located. These registers have fixed locations and 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. The second area of Data Memory is reserved for
general purpose use. All locations within this area are read and write accessible under program
control. The third area is reserved for the LCD Memory. This special area of Data Memory is mapped
directly to the LCD display so data written into this memory area will directly affect the displayed
data. The fourth area is used for the Sine Pattern function. The addresses of the LCD Memory area
and the Sine Pattern Memory area overlap those in the General Purpose Data Memory area.
Structure
The Data Memory is subdivided into several sectors, all of which are implemented in 8-bit wide
RAM. Each of the Data Memory Sector is categorized into two types, the special Purpose Data
Memory and the General Purpose Data Memory. While the 80H~A3H of Sector 1 is LCD Memory
and the 80H~BFH of Sector 2 is Sine Pattern Memory.
The start address of the Data Memory for the device is the address 00H while the start address of
the General Purpose Data Memory, LCD Memory or Sine Pattern Memory is the address 80H. The
Special Purpose Data Memory registers are accessible in all sectors, with the exception of the EEC
register at address 40H, and the FC0, FC1 and FC2 registers at addresses 28H~2AH, which are only
accessible in sector 1. Switching between the different Data Memory sectors is achieved by setting
the Memory Pointers to the correct value.
Device
Capacity
HT45F77
General Purpose: 256×8
Sectors
0: 80H~FFH
1: 80H~A3H (for LCD)
2: 80H~BFH (for Sine Pattern)
3: 80H~FFH
    
Data Memory Structure
General Purpose Data Memory
There are 256 bytes of general purpose data memory which are arranged in 80H~FFH of Sector 0
and Sector 3. All microcontroller programs require an area of read/write memory where temporary
data can be stored and retrieved for use later. It is this area of RAM memory that is known as
General Purpose Data Memory. This area of Data Memory is fully accessible by the user programing
for both reading and writing operations. By using the bit operation instructions individual bits can be
set or reset under program control giving the user a large range of flexibility for bit manipulation in
the Data Memory.
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Special Purpose Data Memory
This area of Data Memory is where registers, necessary for the correct operation of the
microcontroller, are stored. Most of the registers are both readable and writeable but some are
protected and are readable only, the details of which are located under the relevant Special Function
Register section. Note that for locations that are unused, any read instruction to these addresses will
return the value "00H".
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Special Purpose Data Memory
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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, IAR2
The Indirect Addressing Registers, IAR0, IAR1 and IAR2, 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, IAR1 and IAR2 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, MP1L/MP1H or MP2L/MP2H. Acting as a pair, IAR0 and MP0 can together access data only
from Sector 0 while the IAR1 register together with the MP1L/MP1H register pair and IAR2 register
together with the MP2L/MP2H register pair can access data from any Data Memory Sector. As
the Indirect Addressing Registers are not physically implemented, reading the Indirect Addressing
Registers will return a result of "00H" and writing to the registers will result in no operation.
Memory Pointers – MP0, MP1L, MP1H, MP2L, MP2H
Five Memory Pointers, known as MP0, MP1L, MP1H, MP2L, MP2H, 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 Sector 0, while MP1L/MP1H
together with IAR1 and MP2L/MP2H together with IAR2 are used to access data from all sectors
according to the corresponding MP1H or MP2H register. Direct Addressing can be used in all
sectors using the corresponding instruction which can address all available data memory space.
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 1
data .section ´data´
adres1 db ?
adres2 db ?
adres3 db ?
adres4 db ?
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:
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Indirect Addressing Program Example 2
data .section ´data´
adres1 db ?
adres2 db ?
adres3 db ?
adres4 db ?
block db ?
code .section at 0 ´code´
org 00h
start:
mov a, 04h ; setup size of block
mov block, a
mov
a, 01h; setup the memory sector
mov mp1h, a
mov a, offset adres1; Accumulator loaded with first RAM address
mov mp1l, a ; setup memory pointer with first RAM address
loop:
clr IAR1 ; clear the data at address defined by MP1
inc mp1l ; increment memory pointer MP1L
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
Data Memory addresses.
Direct Addressing Program Example using extended instructions
data .section ´data´
temp db ?
code .section at 0 ´code´
org 00h
start:
lmov a, [m] ; move [m] data to acc
lsub a, [m+1] ; compare [m] and [m+1] data
snz
c; [m]>[m+1]?
jmp
continue; no
lmova, [m] ; yes, exchange [m] and [m+1] data
mov temp, a
lmova, [m+1]
lmov[m], a
mov a, temp
lmov[m+1], a
continue:
Note: here "m" is a data memory address located in any data memory sectors. For example,
m=1F0H, it indicates address 0F0H in Sector 1.
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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.
Status Register – STATUS
This 8-bit register contains the SC flag, CZ flag, 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, C, SC and CZ 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.
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• 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.
• CZ is the operational result of different flags for different instructions. Refer to register
definitions for more details.
• SC is the result of the "XOR" operation which is performed by the OV flag and the MSB of the
current instruction operation result.
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
SC
CZ
TO
PDF
OV
Z
AC
C
R/W
R
R
R
R
R/W
R/W
R/W
R/W
POR
x
x
0
0
x
x
x
x
"x" unknown
Bit 7SC: The result of the "XOR" operation which is performed by the OV flag and the
MSB of the instruction operation result.
Bit 6CZ: The operational result of different flags for different instructions.
For SUB/SUBM/LSUB/LSUBM instructions, the CZ flag is equal to the Z flag.
For SBC/ SBCM/ LSBC/ LSBCM instructions, the CZ flag is the "AND" operation
result which is performed by the previous operation CZ flag and current operation zero
flag.
For other instructions, the CZ flag will not be affected.
Bit 5TO: Watchdog Time-Out flag
0: After power up or executing the "CLR WDT" or "HALT" instruction
1: A watchdog time-out occurred.
Bit 4PDF: Power down flag
0: After power up or executing the "CLR WDT" instruction
1: By executing the "HALT" instruction
Bit 3OV: Overflow flag
0: No overflow
1: An operation results in a carry into the highest-order bit but not a carry out of the
highest-order bit or vice versa.
Bit 2Z: Zero flag
0: The result of an arithmetic or logical operation is not zero
1: The result of an arithmetic or logical operation is zero
Bit 1AC: Auxiliary flag
0: No auxiliary carry
1: An operation results in a carry out of the low nibbles in addition, or no borrow
from the high nibble into the low nibble in subtraction
Bit 0C: Carry flag
0: No carry-out
1: An operation results in a carry during an addition operation or if a borrow does
not take place during a subtraction operation
C is also affected by a rotate through carry instruction.
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EEPROM Data Memory
This device contains an area of internal EEPROM Data Memory. EEPROM, which stands for
Electrically Erasable Programmable Read Only Memory, is by its nature a non-volatile form
of re-programmable memory, with data retention even when its power supply is removed. By
incorporating this kind of data memory, a whole new host of application possibilities are made
available to the designer. The availability of EEPROM storage allows information such as product
identification numbers, calibration values, specific user data, system setup data or other product
information to be stored directly within the product microcontroller. The process of reading and
writing data to the EEPROM memory has been reduced to a very trivial affair.
EEPROM Data Memory Structure
The EEPROM Data Memory capacity is 64×8 bits for the device. Unlike the Program Memory and
RAM Data Memory, the EEPROM Data Memory is not directly mapped into memory space and
is therefore not directly addressable in the same way as the other types of memory. Read and Write
operations to the EEPROM are carried out in single byte operations using an address and a data
register in Sector 0 and a single control register in Sector 1.
EEPROM Registers
Three registers control the overall operation of the internal EEPROM Data Memory. These are the
address register, EEA, the data register, EED and a single control register, EEC. As both the EEA
and EED registers are located in Sector 0, they can be directly accessed in the same was as any
other Special Function Register. The EEC register however, being located in Sector1, can be read
from or written to indirectly using the MP1L/MP1H or MP2L/MP2H Memory Pointer and Indirect
Addressing Register, IAR1/IAR2. Because the EEC control register is located at address 40H in
Sector 1, the MP1L or MP2L Memory Pointer must first be set to the value 40H and theMP1H or
MP2H Memory Pointer high byte set to the value, 01H, before any operations on the EEC register
are executed.
EEPROM Register List
Name
Bit
7
6
5
4
3
2
1
0
EEA
—
—
D5
D4
D3
D2
D1
D0
EED
D7
D6
D5
D4
D3
D2
D1
D0
EEC
—
—
—
—
WREN
WR
RDEN
RD
EEA Register
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
—
—
x
x
x
x
x
x
"x" unknown
Bit 7~6
Unimplemented, read as "0"
Bit 5~0D5~D0: Data EEPROM address
Data EEPROM address bit 5 ~ bit 0
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EED 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 7~0D7~D0: Data EEPROM data
Data EEPROM data bit 7 ~ bit 0
EEC Register
Bit
7
6
5
4
3
2
1
0
Name
—
—
—
—
WREN
WR
RDEN
RD
R/W
—
—
—
—
R/W
R/W
R/W
R/W
POR
—
—
—
—
0
0
0
0
Bit 7~4
Unimplemented, read as "0"
Bit 3WREN: Data EEPROM Write Enable
0: Disable
1: Enable
This is the Data EEPROM Write Enable Bit which must be set high before Data
EEPROM write operations are carried out. Clearing this bit to zero will inhibit Data
EEPROM write operations.
Bit 2WR: EEPROM Write Control
0: Write cycle has finished
1: Activate a write cycle
This is the Data EEPROM 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. Setting this bit high will have no effect if
the WREN has not first been set high.
Bit 1RDEN: Data EEPROM Read Enable
0: Disable
1: Enable
This is the Data EEPROM Read Enable Bit which must be set high before Data
EEPROM read operations are carried out. Clearing this bit to zero will inhibit Data
EEPROM read operations.
Bit 0RD: EEPROM Read Control
0: Read cycle has finished
1: Activate a read cycle
This is the Data EEPROM 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 WREN, WR, RDEN and RD can not be set high at the same time in one
instruction. The WR and RD can not be set high at the same time.
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Reading Data from the EEPROM
To read data from the EEPROM, the read enable bit, RDEN, in the EEC register must first be set
high to enable the read function. The EEPROM address of the data to be read must then be placed
in the EEA register. If the RD bit in the EEC register is now set high, a read cycle will be initiated.
Setting the RD bit high will not initiate a read operation if the RDEN bit has not been set. When
the read cycle terminates, the RD bit will be automatically cleared to zero, after which the data can
be read from the EED register. The data will remain in the EED register until another read or write
operation is executed. The application program can poll the RD bit to determine when the data is
valid for reading.
Writing Data to the EEPROM
The EEPROM address of the data to be written must first be placed in the EEA register and the data
placed in the EED register. To write data to the EEPROM, the write enable bit, WREN, in the EEC
register must first be set high to enable the write function. After this, the WR bit in the EEC register
must be immediately set high to initiate a write cycle. These two instructions must be executed
consecutively. The global interrupt bit EMI should also first be cleared before implementing any
write operations, and then set again after the write cycle has started. Note that setting the WR bit
high will not initiate a write cycle if the WREN bit has not been set. As the EEPROM write cycle is
controlled using an internal timer whose operation is asynchronous to microcontroller system clock,
a certain time will elapse before the data will have been written into the EEPROM. Detecting when
the write cycle has finished can be implemented either by polling the WR bit in the EEC register or
by using the EEPROM interrupt. When the write cycle terminates, the WR bit will be automatically
cleared to zero by the microcontroller, informing the user that the data has been written to the
EEPROM. The application program can therefore poll the WR bit to determine when the write cycle
has ended.
Write Protection
Protection against inadvertent write operation is provided in several ways. After the device is
powered-on the Write Enable bit in the control register will be cleared preventing any write
operations. Also at power-on the Memory Pointer pairs, MP1L/MP1H and MP2L/MP2H, will be
reset to zero, which means that Data Memory Sector 0 will be selected. As the EEPROM control
register is located in Sector 1, this adds a further measure of protection against spurious write
operations. During normal program operation, ensuring that the Write Enable bit in the control
register is cleared will safeguard against incorrect write operations.
EEPROM Interrupt
The EEPROM write interrupt is generated when an EEPROM write cycle has ended. The EEPROM
interrupt must first be enabled by setting the DEE bit in the relevant interrupt register. However as
the EEPROM is contained within a Multi-function Interrupt, the associated multi-function interrupt
enable bit must also be set. When an EEPROM write cycle ends, the DEF request flag and its
associated multi-function interrupt request flag will both be set. If the global, EEPROM and Multifunction interrupts are enabled and the stack is not full, a jump to the associated Multi-function
Interrupt vector will take place. When the interrupt is serviced only the Multi-function interrupt flag
will be automatically reset, the EEPROM interrupt flag must be manually reset by the application
program. More details can be obtained in the Interrupt section.
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Programming Considerations
Care must be taken that data is not inadvertently written to the EEPROM. Protection can be
enhanced by ensuring that the Write Enable bit is normally cleared to zero when not writing.
Also the Memory Pointer high byte, MP1H or MP2H, could be normally cleared to zero as this
would inhibit access to Sector 1 where the EEPROM control register exist. Although certainly not
necessary, consideration might be given in the application program to the checking of the validity of
new write data by a simple read back process.
When writing data the WR bit must be set high immediately after the WREN bit has been set high,
to ensure the write cycle executes correctly. The global interrupt bit EMI should also be cleared
before a write cycle is executed and then re-enabled after the write cycle starts. Note that the device
should not enter the IDLE or SLEEP mode until the EEPROM read or write operation is totally
complete. Otherwise, the EEPROM read or write operation will fail.
Programming Examples
• Reading data from the EEPROM - polling method
MOV A, EEPROM_ADRES
MOV EEA, A
MOV A, 040H MOV MP1L, A MOV A, 01H MOV MP1H, A
SET IAR1.1 SET IAR1.0 BACK:
SZ IAR1.0 JMP BACK
CLR IAR1 CLR MP1H
MOV A, EED MOV READ_DATA, A
; user defined address
; setup memory pointer MP1L
; MP1 points to EEC register
; setup memory pointer MP1H
; set RDEN bit, enable read operations
; start Read Cycle - set RD bit
; check for read cycle end
; disable EEPROM read/write
; move read data to register
• Writing Data to the EEPROM - polling method
MOV A, EEPROM_ADRES
MOV EEA, A
MOV A, EEPROM_DATA
MOV EED, A
MOV A, 040H MOV MP1L, A MOV A, 01H MOV MP1H, A
CLR EMI
SET IAR1.3 SET IAR1.2 SET EMI
BACK:
SZ IAR1.2 JMP BACK
CLR IAR1 CLR MP1H
Rev. 1.10
; user defined address
; user defined data
; setup memory pointer MP1L
; MP1 points to EEC register
; setup memory pointer MP1H
; set WREN bit, enable write operations
; start Write Cycle - set WR bit – executed immediately
; after set WREN bit
; check for write cycle end
; disable EEPROM read/write
42
January 19, 2015
HT45F77
Body Fat Scale 8-Bit Flash MCU
Oscillators
Various oscillator options offer the user a wide range of functions according to their various
application requirements. The flexible features of the oscillator functions ensure that the best
optimisation can be achieved in terms of speed and power saving. Oscillator selections and operation
are selected through a combination of configuration options and registers.
Oscillator Overview
In addition to being the source of the main system clock the oscillators also provide clock sources
for the Watchdog Timer and Time Base Interrupts. External oscillators requiring some external
components as well as fully integrated internal oscillators, requiring no external components,
are provided to form a wide range of both fast and slow system oscillators. All oscillator options
are selected through the configuration options. The higher frequency oscillators provide higher
performance but carry with it the disadvantage of higher power requirements, while the opposite
is of course true for the lower frequency oscillators. With the capability of dynamically switching
between fast and slow system clock, 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
400kHz~20MHz
OSC1/OSC2
Internal High Speed RC
HIRC
4.8, 4.8×2 or 4.8×3MHz
—
External Low Speed Crystal
LXT
32.768kHz
XT1/XT2
Internal Low Speed RC
LIRC
32kHz
—
Oscillator Types
System Clock Configurations
There are four methods of generating the system clock, two high speed oscillators and two low speed
oscillators. The high speed oscillators are the external crystal oscillator and the internal 4.8MHz,
4.8×2MHz or 4.8×3MHz RC oscillator. The two low speed oscillators are the internal 32kHz RC
oscillator and the external 32.768kHz crystal 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 and low speed oscillators is chosen
via configuration options. The frequency of the slow speed or high speed system clock is also
determined using the HLCLK bit and CKS2~CKS0 bits in the SMOD register. Note that two
oscillator selections must be made namely one high speed and one low speed system oscillators. It is
not possible to choose a no-oscillator selection for either the high or low speed oscillator.
Rev. 1.10
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January 19, 2015
HT45F77
Body Fat Scale 8-Bit Flash MCU
High Speed
Oscillato�
HXT
fH
6-stage P�escale�
HIRC
fH/�
fH/4
High Speed Oscillato�
Config��ation Option
Low Speed
Oscillato�
LIRC
fH/8
fH/16
fH/3�
fH/64
fSYS
fSUB
LXT
HLCLK�
CKS�~CKS0 bits
Low Speed Oscillato�
Config��ation Option
fSUB
Fast Wake-�p f�om SLEEP Mode o�
IDLE Mode Cont�ol (fo� HXT onl�)
System Clock Configurations
External Crystal/Ceramic Oscillator – HXT
The External Crystal/Ceramic System Oscillator is one of the high frequency oscillator choices,
which is selected via configuration option. For most crystal oscillator configurations, the simple
connection of a crystal across OSC1 and OSC2 will create the necessary phase shift and feedback for
oscillation, without requiring external capacitors. However, for some crystal types and frequencies,
to ensure oscillation, it may be necessary to add two small value capacitors, C1 and C2. Using a
ceramic resonator will usually require two small value capacitors, C1 and C2, to be connected as
shown for oscillation to occur. The values of C1 and C2 should be selected in consultation with the
crystal or resonator manufacturer’s specification.
For oscillator stability and to minimise the effects of noise and crosstalk, it is important to ensure
thatthe crystal and any associated resistors andcapacitors along with interconnectinglines are all
located as close to the MCUas possible.
     Crystal/Resonator Oscillator – HXT
Rev. 1.10
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Body Fat Scale 8-Bit Flash MCU
Crystal Oscillator C1 and C2 Values
Crystal Frequency
C1
C2
20MHz
0pF
0pF
12MHz
0pF
0pF
8MHz
0pF
0pF
4MHz
0pF
0pF
1MHz
100pF
100pF
Note: C1 and C2 values are for guidance only.
Crystal Recommended Capacitor Values
Internal RC Oscillator – HIRC
The internal RC oscillator is a fully integrated system oscillator requiring no external components.
The internal RC oscillator has three fixed frequencies of either 4.8MHz, 4.8×2MHz or 4.8×3MHz.
Device trimming during the manufacturing process and the inclusion of internal frequency
compensation circuits are used to ensure that the influence of the power supply voltage, temperature
and process variations on the oscillation frequency are minimised. As a result, at a power supply of
5V and at a temperature of 25°C degrees, the fixed oscillation frequency of 4.8×2MHz will have
a tolerance within 2%. Note that if this internal system clock option is selected, as it requires no
external pins for its operation, I/O pins PB1 and PB2 are free for use as normal I/O pins.
Internal 32kHz Oscillator – LIRC
The Internal 32kHz System Oscillator is one of the low frequency oscillator choices, which is
selected via configuration option. It is a fully integrated RC oscillator with a typical frequency of
32kHz at 5V, requiring no external components for its implementation. Device trimming during
the manufacturing process and the inclusion of internal frequency compensation circuits are used
to ensure that the influence of the power supply voltage, temperature and process variations on the
oscillation frequency are minimised. As a result, at a power supply of 5V and at a temperature of
25°C degrees, the fixed oscillation frequency of 32kHz will have a tolerance within 10%.
External 32.768kHz Crystal Oscillator – LXT
The External 32.768kHz Crystal System Oscillator is one of the low frequency oscillator choices,
which is selected via configuration option. This clock source has a fixed frequency of 32.768kHz and
requires a 32.768kHz crystal to be connected between pins XT1 and XT2. The external resistor and
capacitor components connected to the 32.768kHz crystal are necessary to provide oscillation. For
applications where precise frequencies are essential, these components may be required to provide
frequency compensation due to different crystal manufacturing tolerances. During power-up there is
a time delay associated with the LXT oscillator waiting for it to start-up.
When the microcontroller enters the SLEEP or IDLE Mode, the system clock is switched off to stop
microcontroller activity and to conserve power. However, in many microcontroller applications it
may be necessary to keep the internal timers operational even when the microcontroller is in the
SLEEP or IDLE Mode. To do this, another clock, independent of the system clock, must be provided.
However, for some crystals, to ensure oscillation and accurate frequency generation, it is necessary
to add two small value external capacitors, C1 and C2. The exact values of C1 and C2 should
be selected in consultation with the crystal or resonator manufacturer specification. The external
parallel feedback resistor, RP, is required.
Rev. 1.10
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January 19, 2015
HT45F77
Body Fat Scale 8-Bit Flash MCU
Some configuration options determine if the XT1/XT2 pins are used for the LXT oscillator or as I/O pins.
• If the LXT oscillator is not used for any clock source, the XT1/XT2 pins can be used as normal I/O
pins.
• If the LXT oscillator is used for any clock source, the 32.768kHz crystal should be connected to
the XT1/XT2 pins.
For oscillator stability and to minimise the effects of noise and crosstalk, it is important to ensure
thatthe crystal and any associated resistors andcapacitors along with interconnectinglines are all
located as close to the MCUas possible.
‚   
­ €
  ‚  External LXT Oscillator
LXT Oscillator C1 and C2 Values
Crystal Frequency
C1
C2
32.768kHz
10pF
10pF
Note: 1. C1 and C2 values are for guidance only.
2. RP=5M~10MΩ is recommended.
32.768kHz Crystal Recommended Capacitor Values
LXT Oscillator Low Power Function
The LXT oscillator can function in one of two modes, the Quick Start Mode and the Low Power
Mode. The mode selection is executed using the LXTLP bit in the TBC register.
TBC Register
Bit
7
6
5
4
3
2
1
0
Name
TBON
TBCK
TB11
TB10
LXTLP
TB02
TB01
TB00
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
0
1
1
0
1
1
1
Bit 7TBON: TB0 and TB1 Control
Described elsewhere.
Bit 6TBCK: Select fTB Clock
Described elsewhere.
Bit 5~4TB11~TB10: Select Time Base 1 Time-out Period
Described elsewhere.
Bit 3LXTLP: LXT Low Power Control
0: Quick Start Mode
1: Low Power Mode
Bit 2~0TB02~TB00: Select Time Base 0 Time-out Period
Described elsewhere.
Rev. 1.10
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January 19, 2015
HT45F77
Body Fat Scale 8-Bit Flash MCU
After power on, the LXTLP bit will be automatically cleared to zero ensuring that the LXT oscillator
is in the Quick Start operating mode. In the Quick Start Mode the LXT oscillator will power up
and stabilise quickly. However, after the LXT oscillator has fully powered up it can be placed
into the Low-power mode by setting the LXTLP bit high. The oscillator will continue to run but
with reduced current consumption, as the higher current consumption is only required during the
LXT oscillator start-up. In power sensitive applications, such as battery applications, where power
consumption must be kept to a minimum, it is therefore recommended that the application program
sets the LXTLP bit high about 2 seconds after power-on.
It should be noted that, no matter what condition the LXTLP bit is set to, the LXT oscillator will
always be function normally, the only difference is that it will take more time to start up if in the
Low-power mode.
Supplementary Oscillators
The low speed oscillators, in addition to providing a system clock source are also used to provide
a clock source to other device functions. These are the Watchdog Timer, the Time Base Interrupts
function, the LCD driver, and the SIM.
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 this device with both high and low speed clock
sources and the means to switch between them dynamically, the user can optimise the operation of
their microcontroller to achieve the best performance/power ratio.
System Clocks
The 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 fSUB 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 an HXT or HIRC oscillator, selected via a configuration option.
The low speed system clock source can be sourced from internal clock fSUB. If fSUB is selected then it
can be sourced by either the LXT or LIRC oscillator, selected via a configuration option. The other
choice, which is a divided version of the high speed system oscillator has a range of fH/2~fH/64.
The fSUB clock is used to provide a substitute clock for the microcontroller just after a wake-up has
occurred to enable faster wake-up times. The fSUB is used as a clock source for the Watchdog timer,
the Time Base interrupt, the TMs, the LCD and the SIM functions.
Rev. 1.10
47
January 19, 2015
HT45F77
Body Fat Scale 8-Bit Flash MCU
High Speed
Oscillato�
HXT
fH
6-stage P�escale�
HIRC
fH/�
fH/4
High Speed Oscillato�
Config��ation Option
Low Speed
Oscillato�
LIRC
fH/8
fH/16
fH/3�
fH/64
fSYS
fSUB
LXT
HLCLK�
CKS�~CKS0 bits
Low Speed Oscillato�
Config��ation Option
fSUB
Fast Wake-�p f�om SLEEP Mode o�
IDLE Mode Cont�ol (fo� HXT onl�)
fSUB
fTB
Time Base
fSYS/4
TBCK
fSUB
fS
WDT
fSYS/4
Config��ation Option
fSUB
fSUB
fSYS
÷8
4KHz
Clock So��ce
Selection
LCD D�ive�
SIM
System Clock Configurations
Note: When the system clock source fSYS is switched to fSUB from fH, the high speed oscillation will stop to
conserve the power. Thus there is no fH~fH/64 for peripheral circuit to use.
Rev. 1.10
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January 19, 2015
HT45F77
Body Fat Scale 8-Bit Flash MCU
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.
Operating Mode
Description
CPU
fSYS
fSUB
fS
NORMAL Mode
on
fH~fH/64
on
on
SLOW Mode
on
fSUB
on
on
IDLE0 Mode
off
off
on
on/off
IDLE1 Mode
off
on
on
on
SLEEP0 Mode
off
off
off
off
SLEEP1 Mode
off
off
on
on
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 used will be from one of the low speed oscillators, either the LXT
or the LIRC. Running the microcontroller in this mode allows it to run with much lower operating
currents. In the SLOW Mode, the fH is off.
SLEEP0 Mode
The SLEEP Mode is entered when an HALT instruction is executed and when the IDLEN bit in the
SMOD register is low. In the SLEEP0 mode the CPU will be stopped, and the fSUB and fS clocks
will be stopped too, and the Watchdog Timer function is disabled. In this mode, the LVDEN is must
cleared to zero. If the LVDEN is set high, it won’t enter the SLEEP0 Mode.
SLEEP1 Mode
The SLEEP 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 and fS
clocks will continue to operate if the LVDEN is "1" or the Watchdog Timer function is enabled and
if its clock source is chosen via configuration option to come from the fSUB.
Rev. 1.10
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January 19, 2015
HT45F77
Body Fat Scale 8-Bit Flash MCU
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, LCD driver and SIM. In the IDLE0 Mode, the
system oscillator will be stopped. In the IDLE0 Mode the Watchdog Timer clock, fS, will either be
on or off depending upon the fS clock source. If the source is fSYS/4 then the fS clock will be off, and
if the source comes from fSUB then fS 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, LCD driver 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, fS, will
be on. If the source is fSYS/4 then the fS clock will be on, and if the source comes from fSUB then fS
will be on.
Control Register
The registers, SMOD and CTRL, are used for overall control of the internal clocks within the
device.
SMOD Register
Bit
7
6
5
4
3
2
1
0
Name
CKS2
CKS1
CKS0
FSTEN
LTO
HTO
IDLEN
HLCLK
R/W
R/W
R/W
R/W
R/W
R
R
R/W
R/W
POR
0
0
0
0
0
0
1
1
Bit 7~5CKS2~CKS0: The system clock selection when HLCLK is "0"
000: fSUB (fLXT or fLIRC)
001: fSUB (fLXT or fLIRC)
010: fH/64
011: fH/32
100: fH/16
101: fH/8
110: fH/4
111: fH/2
These three bits are used to select which clock is used as the system clock source. In
addition to the system clock source, which can be either the LXT or LIRC, a divided
version of the high speed system oscillator can also be chosen as the system clock
source.
Bit 4FSTEN: Fast Wake-up Control (only for HXT)
0: Disable
1: Enable
This is the Fast Wake-up Control bit which determines if the fSUB clock source is
initially used after the device wakes up. When the bit is high, the fSUB clock source can
be used as a temporary system clock to provide a faster wake up time as the fSUB clock
is available.
Rev. 1.10
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January 19, 2015
HT45F77
Body Fat Scale 8-Bit Flash MCU
Bit 3LTO: Low speed system oscillator ready flag
0: Not ready
1: Ready
This is the low speed system oscillator ready flag which indicates when the low speed
system oscillator is stable after power on reset or a wake-up has occurred. The flag
will be low when in the SLEEP0 Mode but after a wake-up has occurred, the flag will
change to a high level after 1024 clock cycles if the LXT oscillator is used and 1~2
clock cycles if the LIRC oscillator is used.
Bit 2HTO: High speed system oscillator ready flag
0: Not ready
1: Ready
This is the high speed system oscillator ready flag which indicates when the high speed
system oscillator is stable. This flag is cleared to zero 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 wakeup has occurred, the flag will change to a high level after 1024 clock cycles if the HXT
oscillator is used and after 15~16 clock cycles if the HIRC oscillator is used.
Bit 1IDLEN: IDLE Mode control
0: Disable
1: Enable
This is the IDLE Mode Control bit and determines what happens when the HALT
instruction is executed. If this bit is high, when a HALT instruction is executed 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.
Bit 0HLCLK: system clock selection
0: fH/2 ~ fH/64 or fSUB
1: fH
This bit is used to select if the fH clock or the fH/2~fH/64 or fSUB clock is used as
the system clock. When the bit is high the fH clock will be selected and if low the
fH/2~fH/64 or fSUB clock will be selected. When system clock switches from the fH
clock to the fSUB clock and the fH clock will be automatically switched off to conserve
power.
CTRL Register
Bit
7
6
5
4
3
2
1
0
Name
FSYSON
—
—
—
—
R/W
R/W
—
—
—
—
LVRF
LRF
WRF
R/W
R/W
R/W
POR
0
—
—
—
—
x
0
0
"x" unknown
Bit 7FSYSON: fSYS Control in IDLE Mode
0: Disable
1: Enable
Bit 6~3
Unimplemented, read as "0"
Bit 2LVRF: LVR function reset flag
Described elsewhere.
Bit 1LRF: LVR Control register software reset flag
Described elsewhere.
Bit 0WRF: WDT Control register software reset flag
Described elsewhere.
Rev. 1.10
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January 19, 2015
HT45F77
Body Fat Scale 8-Bit Flash MCU
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 fSUB, namely either the LXT or LIRC oscillator, to act as a temporary clock
to first drive the system until the original system oscillator has stabilised. As the clock source for
the Fast Wake-up function is fSUB, the Fast Wake-up function is only available in the SLEEP1 and
IDLE0 modes. When the device is woken up from the SLEEP0 mode, the Fast Wake-up function has
no effect because the fSUB clock is stopped. The Fast Wake-up enable/disable function is controlled
using the FSTEN bit in the SMOD register.
If the HXT oscillator is selected as the NORMAL Mode system clock, and if the Fast Wake-up
function is enabled, then it will take one to two tSUB clock cycles of the LIRC or LXT oscillator for
the system to wake-up. The system will then initially run under the fSUB clock source until 1024
HXT clock cycles have elapsed, at which point the HTO flag will switch high and the system will
switch over to operating from the HXT oscillator.
If the HIRC oscillator or LIRC oscillator is used as the system oscillator then it will take 15~16
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)
1024 HXT cycles
1024 HXT cycles
1~2 HXT cycles
1
1024 HXT cycles
1~2 fSUB cycles
(System runs with fSUB first for 1024
HXT cycles and then switches over
to run with the HXT clock)
1~2 HXT cycles
HIRC
×
15~16 HIRC cycles
15~16 HIRC cycles
1~2 HIRC cycles
LIRC
×
1~2 LIRC cycles
1~2 LIRC cycles
1~2 LIRC cycles
LXT
×
1024 LXT cycles
1024 LXT cycles
1~2 LXT cycles
0
HXT
Wake-up Time
(IDLE0 Mode)
Wake-up Time
(IDLE1 Mode)
"×": don’t care
Wake-Up Times
Note that if the Watchdog Timer is disabled, which means that the LXT and LIRC are all both off,
then there will be no Fast Wake-up function available when the device wake-up from the SLEEP0
Mode.
Rev. 1.10
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January 19, 2015
HT45F77
Body Fat Scale 8-Bit Flash MCU
Operating Mode Switching
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 fSUB. If the clock is from the fSUB, 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.
­ €   
­ €    Rev. 1.10
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January 19, 2015
HT45F77
Body Fat Scale 8-Bit Flash MCU
NORMAL Mode to SLOW Mode Switching
When running in the NORMAL Mode, which uses the high speed system oscillator, and therefore
consumes more power, the system clock can switch to run in the SLOW Mode by set the HLCLK bit
to "0" and set the CKS2~CKS0 bits to "000" or "001" in the SMOD register. This will then use the
low speed system oscillator which will consume less power. Users may decide to do this for certain
operations which do not require high performance and can subsequently reduce power consumption.
The SLOW Mode is sourced from the LXT or the LIRC oscillators and therefore requires these
oscillators to be stable before full mode switching occurs. This is monitored using the LTO bit in the
SMOD register.
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54
January 19, 2015
HT45F77
Body Fat Scale 8-Bit Flash MCU
SLOW Mode to NORMAL Mode Switching
In SLOW Mode the system uses either the LXT or LIRC low speed system oscillator. To switch
back to the NORMAL Mode, where the high speed system oscillator is used, the HLCLK bit should
be set high 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.
  
     ­          ­   € ‚      ­   € ‚      ­   Rev. 1.10
55
January 19, 2015
HT45F77
Body Fat Scale 8-Bit Flash MCU
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 the fSUB 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 no matter if the WDT clock source originates from the fSUB
clock or from the system clock.
• 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 clock source is selected to come from
the fSUB clock as the WDT is enabled.
• The I/O ports will maintain their present conditions.
• In the status register, the Power Down flag, PDF, will be set and the Watchdog time-out flag, TO,
will be cleared.
Entering the IDLE0 Mode
There is only one way for 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 clock source is selected to come from
the fSUB clock and the WDT is enabled. The WDT will stop if its clock source originates from the
system clock.
• The I/O ports will maintain their present conditions.
• In the status register, the Power Down flag, PDF, will be set and the Watchdog time-out flag, TO,
will be cleared.
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Entering the 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 the 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 regardless of the WDT
clock source which originates from the fSUB clock or from the system clock.
• 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 the device which has different package types, as there may be unbonbed pins.
These must either be setup as outputs or if setup as inputs must have pull-high resistors connected.
Care must also be taken with the loads, which are connected to I/O pins, which are setup as outputs.
These should be placed in a condition in which minimum current is drawn or connected only to
external circuits that do not draw current, such as other CMOS inputs. Also note that additional
standby current will also be required if the configuration options have enabled the LXT or LIRC
oscillator.
In the IDLE1 Mode the system oscillator is on, if the system oscillator is from the high speed system
oscillator, the additional standby current will also be perhaps in the order of several hundred microamps.
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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 falling edge on Port A
• A system interrupt
• A WDT overflow
If the device is woken up by a WDT overflow, a Watchdog Timer reset will be initiated. 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 Port A can be setup using the PAWU register to permit a negative transition on the pin
to wake-up the system. When a Port A pin wake-up occurs, the program will resume execution at
the instruction following the "HALT" instruction. If the system is woken up by an interrupt, then
two possible situations may occur. The first is where the related interrupt is disabled or the interrupt
is enabled but the stack is full, in which case the program will resume execution at the instruction
following the "HALT" instruction. In this situation, the interrupt which woke-up 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
The HXT and LXT oscillators both use the same SST counter. For example, if the system is woken
up from the SLEEP0 Mode and both the HXT and LXT oscillators need to start-up from an off state.
The LXT oscillator uses the SST counter after HXT oscillator has finished its SST period.
• If 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". At this
time, the LXT oscillator may not be stability if fSUB is from LXT oscillator. The same situation
occurs in the power-on state. The LXT oscillator is not ready yet when the first instruction is
executed.
• If 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 LXT or
LIRC oscillator after wake up.
• There are peripheral functions, such as WDT, TMs, LCD driver and SIM, for which the fSYS is
used. If the system clock source is switched from fH to fSUB, the clock source to the peripheral
functions mentioned above will change accordingly.
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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, fS, which is in turn supplied by
one of two sources selected by configuration option: fSUB or fSYS/4. The fSUB clock can be sourced
from either the LXT or LIRC oscillators, again chosen via a configuration option. 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 LXT
oscillator is supplied by an external 32.768kHz crystal. The other Watchdog Timer clock source
option is the fSYS/4 clock.
Watchdog Timer Control Register
A single register, WDTC, controls the required timeout period as well as the enable/disable
operation. This register together with several configuration options control the overall operation of
the Watchdog Timer.
WDTC Register
Bit
7
6
5
4
3
2
1
0
Name
WE4
WE3
WE2
WE1
WE0
WS2
WS1
WS0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
1
0
1
0
0
1
1
Bit 7~3WE4~WE0: WDT function software control
If the WDT configuration option is "always enable":
10101 or 01010: Enable
Others: Reset MCU
If the WDT configuration option is "controlled by the WDT control register":
10101: Disable
01010: Enable
Others: Reset MCU
When these bits are changed by the environmental noise or software setting to reset
the microcontroller, the reset operation will be activated after 2~3 fSUB clock cycles
and the WRF bit in the CTRL register will be set high.
Bit 2~0WS2~WS0: WDT time-out period selection
000: 28/fS
001: 210/fS
010: 212/fS
011: 214/fS
100: 215/fS
101: 216/fS
110: 217/fS
111: 218/fS
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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
"x" unknown
Bit 7FSYSON: fSYS Control in IDLE Mode
Described elsewhere.
Bit 6~3
Unimplemented, read as "0"
Bit 2LVRF: LVR function reset flag
Described elsewhere.
Bit 1LRF: LVR Control register software reset flag
Described elsewhere.
Bit 0WRF: WDT Control register software reset flag
0: Not occur
1: Occurred
This bit is set high by the WDT Control register software reset and cleared by the
application program. Note that this bit can only be cleared to zero 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. Some of the
Watchdog Timer options, such as always on select using configuration options. 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. If the WDT configuration
option is determined that the WDT function is always enabled, the WE4~WE0 bits still have
effects on the WDT function. When the WE4~WE0 bits value is equal to 01010B or 10101B, the
WDT function is enabled. However, if the WE4~WE0 bits are changed to any other values except
01010B and 10101B, which is caused by the environmental noise or software setting, it will reset
the microcontroller after 2~3 fSUB clock cycles. If the WDT configuration option is determined that
the WDT function is controlled by the WDT control register, the WE4~WE0 values can determine
which mode the WDT operates in. The WDT function 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 bits value is equal to
01010B. If the WE4~WE0 bits are set to any other values by the environmental noise or software
setting, except 01010B and 10101B, it will reset the device after 2~3 fSUB clock cycles. After power
on these bits will have the value of 01010B.
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WDT Configuration Option
Always Enable
Controlled by WDT Control Register
WE4 ~ WE0 Bits
WDT Function
01010B or 10101B
Enable
Any other values
Reset MCU
10101B
Disable
01010B
Enable
Any other values
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 contents of the Watchdog Timer.
The first is a WDT reset, which means a certain value except 01010B and 10101B written into the
WE4~WE0 bit filed, the second is using 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. That is to use
the single "CLR WDT" instruction to clear the WDT.
The maximum time out period is when the 218 division ratio is selected. As an example, with a
32kHz LIRC oscillator as its source clock, this will give a maximum watchdog period of around 8
second for the 218 division ratio, and a minimum timeout of 7.8ms for the 28 division ration.
WDTC Registe�
WE4~WE0 bits
Reset MCU
CLR
“HALT” Inst��ction
“CLR WDT” Inst��ction
fSYS/4
LXT
LIRC
M
U
X
fSUB
Config��ation
option
M
U
X
fS
Config��ation
option
8-stage Divide�
fS/�8
WS�~WS0
WDT P�escale�
WDT Time-o�t
8-to-1 MUX
Watchdog Timer
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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. 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 commences. 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.
Another type of reset is when the Watchdog Timer overflows and resets. 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, is implemented in situations where the power supply voltage falls
below a certain threshold.
Reset Functions
There are four ways in which a reset can occur internally.
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 I/O ports will be first set to inputs.
Note: tRSTD is power-on delay, typical time=50ms
Power-On Reset Timing Chart
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Low Voltage Reset – LVR
The microcontroller contains a low voltage reset circuit in order to monitor the supply voltage of the
device. 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,
the LVR will automatically reset the device internally and the LVRF bit in the CTRL register will
also be set high. 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 LVS7~LVS0 bits in
the LVRC register. If the LVS7~LVS0 bits are changed to some certain values by the environmental
noise or software setting, the LVR will reset the device after 2~3 fSUB clock cycles. When this
happens, the LRF bit in the CTRL register will be set high. 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.
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 7~0LVS7~LVS0: LVR voltage select
01010101: 2.1V
00110011: 2.55V
10011001: 3.15V
10101010: 3.8V
Other values: 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 fSUB 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 fSUB
clock cycles. However in this situation the register contents will be reset to the POR
value.
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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
"x" unknown
Bit 7FSYSON: fSYS Control in IDLE Mode
Described elsewhere.
Bit 6~3
Unimplemented, read as "0"
Bit 2LVRF: LVR function reset flag
0: Not occur
1: Occurred
This bit is set high when a specific Low Voltage Reset situation condition occurs. This
bit can only be cleared to zero by the application program.
Bit 1LRF: LVR Control register software reset flag
0: Not occur
1: Occurred
This bit is set high 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
zero by the application program.
Bit 0WRF: WDT Control register software reset flag
Described elsewhere.
Watchdog Time-out Reset during Normal Operation
The Watchdog time-out Reset during normal operation is the same as LVR reset except that the
Watchdog time-out flag TO will be set high.
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 zero and the TO flag will be set high. 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 or LXT. The tSST is 1~2 clock for LIRC.
WDT Time-out Reset during Sleep or IDLE Mode Timing Chart
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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
Reset Conditions
0
0
Power-on reset
u
u
LVR 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
Note: "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
Rev. 1.10
Condition after Reset
Program Counter
Reset to zero
Interrupts
All interrupts will be disabled
WDT
Clear after reset, WDT begins counting
Timer Modules
Timer Modules will be turned off
Input/Output Ports
I/O ports will be setup as inputs, and AN0~AN3 as A/D input pin.
Stack Pointer
Stack Pointer will point to the top of the stack
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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.
Power On Reset
LVR Reset
(Normal Operation)
WDT Time-out
(Normal Operation)
WDT Time-out
(HALT)
MP0
0000 0000
0000 0000
0000 0000
uuuu uuuu
MP1L
0000 0000
0000 0000
0000 0000
uuuu uuuu
MP1H
0000 0000
0000 0000
0000 0000
uuuu uuuu
MP2L
0000 0000
0000 0000
0000 0000
uuuu uuuu
MP2H
0000 0000
0000 0000
0000 0000
uuuu uuuu
IAR0
xxxx xxxx
uuuu uuuu
uuuu uuuu
uuuu uuuu
IAR1
xxxx xxxx
uuuu uuuu
uuuu uuuu
uuuu uuuu
IAR2
xxxx xxxx
uuuu uuuu
uuuu uuuu
uuuu uuuu
ACC
xxxx xxxx
uuuu uuuu
uuuu uuuu
uuuu uuuu
PCL
0000 0000
0000 0000
0000 0000
0000 0000
TBLP
xxxx xxxx
uuuu uuuu
uuuu uuuu
uuuu uuuu
TBLH
xxxx xxxx
uuuu uuuu
uuuu uuuu
uuuu uuuu
TBHP
---x xxxx
---u uuuu
---u uuuu
---u uuuu
STATUS
xx00 xxxx
xxuu uuuu
xx1u uuuu
x x 11 u u u u
SMOD
0 0 0 0 0 0 11
0 0 0 0 0 0 11
0 0 0 0 0 0 11
uuuu uuuu
INTEG
---- 0000
---- 0000
---- 0000
---- uuuu
LVDC
--00 -000
--00 -000
--00 -000
--uu –uuu
INTC0
-000 0000
-000 0000
-000 0000
-uuu uuuu
INTC1
0000 0000
0000 0000
0000 0000
uuuu uuuu
INTC2
--00 --00
--00 --00
--00 --00
--uu –uu
MFI0
--00 --00
--00 --00
--00 --00
--uu –uu
MFI1
0000 0000
0000 0000
0000 0000
uuuu uuuu
MFI2
0-00 0-00
0-00 0-00
0-00 0-00
u-uu u-uu
MFI3
--00 --00
--00 --00
--00 --00
--uu –uu
Register
PAWU
0000 0000
0000 0000
0000 0000
uuuu uuuu
PAPU
0000 0000
0000 0000
0000 0000
uuuu uuuu
PA
1111 1111
1111 1111
1111 1111
uuuu uuuu
PAC
1111 1111
1111 1111
1111 1111
uuuu uuuu
PBPU
---0 0000
---0 0000
---0 0000
---u uuuu
PB
- - - 1 1111
- - - 1 1111
- - - 1 1111
---u uuuu
PBC
- - - 1 1111
- - - 1 1111
- - - 1 1111
---u uuuu
PCPU
0000 000-
0000 000-
0000 000-
uuuu uuu-
PC
1111 111 -
1111 111 -
1111 111 -
uuuu uuu-
PCC
1111 111 -
1111 111 -
1111 111 -
uuuu uuu-
PDPU
0000 0000
0000 0000
0000 0000
uuuu uuuu
PD
1111 1111
1111 1111
1111 1111
uuuu uuuu
PDC
1111 1111
1111 1111
1111 1111
uuuu uuuu
PEPU
0000 0000
0000 0000
0000 0000
uuuu uuuu
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Power On Reset
LVR Reset
(Normal Operation)
WDT Time-out
(Normal Operation)
WDT Time-out
(HALT)
PE
1111 1111
1111 1111
1111 1111
uuuu uuuu
PEC
1111 1111
1111 1111
1111 1111
uuuu uuuu
WDTC
0 1 0 1 0 0 11
0 1 0 1 0 0 11
0 1 0 1 0 0 11
uuuu uuuu
TBC
0 0 11 0 111
0 0 11 0 111
0 0 11 0 111
uuuu uuuu
TM0C0
0000 0000
0000 0000
0000 0000
uuuu uuuu
TM0C1
0000 0000
0000 0000
0000 0000
uuuu uuuu
TM0DL
0000 0000
0000 0000
0000 0000
uuuu uuuu
TM0DH
---- --00
---- --00
---- --00
---- --uu
TM0AL
0000 0000
0000 0000
0000 0000
uuuu uuuu
TM0AH
---- --00
---- --00
---- --00
---- --uu
PTM1C0
0000 0---
0000 0---
0000 0---
uuuu u---
PTM1C1
0000 0000
0000 0000
0000 0000
uuuu uuuu
PTM1DL
0000 0000
0000 0000
0000 0000
uuuu uuuu
PTM1DH
---- --00
---- --00
---- --00
---- --uu
PTM1AL
0000 0000
0000 0000
0000 0000
uuuu uuuu
PTM1AH
---- --00
---- --00
---- --00
---- --uu
PTM2C0
0000 0---
0000 0---
0000 0---
uuuu u---
PTM2C1
0000 0000
0000 0000
0000 0000
uuuu uuuu
PTM2DL
0000 0000
0000 0000
0000 0000
uuuu uuuu
PTM2DH
---- --00
---- --00
---- --00
---- --uu
PTM2AL
0000 0000
0000 0000
0000 0000
uuuu uuuu
PTM2AH
---- --00
---- --00
---- --00
---- --uu
PTM1RPL
0000 0000
0000 0000
0000 0000
uuuu uuuu
PTM1RPH
---- --00
---- --00
---- --00
---- --uu
PTM2RPL
0000 0000
0000 0000
0000 0000
uuuu uuuu
Register
PTM2RPH
---- --00
---- --00
---- --00
---- --uu
LCDC
0-00 ---0
0-00 ---0
0-00 ---0
u-uu ---u
LCD1
0000 0000
0000 0000
0000 0000
uuuu uuuu
LCD2
0000 0000
0000 0000
0000 0000
uuuu uuuu
LCD3
0000 0000
0000 0000
0000 0000
uuuu uuuu
PWRC
00-- -000
00-- -000
00-- -000
uu-- -uuu
PGAC0
-000 0000
-000 0000
-000 0000
-uuu uuuu
PGAC1
10-- 000-
10-- 000-
10-- 000-
uu-- uuu-
PGACS
--00 0000
--00 0000
--00 0000
--uu uuuu
USR
0 0 0 0 1 0 11
0 0 0 0 1 0 11
0 0 0 0 1 0 11
uuuu uuuu
UCR1
0000 00x0
0000 00x0
0000 00x0
uuuu uuuu
UCR2
0000 0000
0000 0000
0000 0000
uuuu uuuu
BRG
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
TXRRXR
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
IRCTRL0
0000 0000
0000 0000
0000 0000
uuuu uuuu
IRCTRL1
---- ---0
---- ---0
---- ---0
---- ---u
ADCR0
0010 00-0
0010 00-0
0010 00-0
uuuu uu-u
Rev. 1.10
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Power On Reset
LVR Reset
(Normal Operation)
WDT Time-out
(Normal Operation)
WDT Time-out
(HALT)
ADCR1
0000 000-
0000 000-
0000 000-
uuuu uuu-
ADRL
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
ADRM
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
ADRH
---- xxxx
---- xxxx
---- xxxx
---- uuuu
ADCS
---0 0000
---0 0000
---0 0000
---u uuuu
SPIC0
111 - - - 0 -
111 - - - 0 -
111 - - - 0 -
uuu- --u-
SPIC1
--00 0000
--00 0000
--00 0000
--uu uuuu
SPID
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
LVRC
0101 0101
0101 0101
0101 0101
uuuu uuuu
CTRL
0--- -x00
0--- -x00
0--- -x00
u--- -uuu
SIMC0
111 - 0 0 0 0
111 - 0 0 0 0
111 - 0 0 0 0
uuu- uuuu
SIMC1
1000 0001
1000 0001
1000 0001
uuuu uuuu
SIMA/SIMC2
0000 0000
0000 0000
0000 0000
uuuu uuuu
SIMD
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
SIMTOC
0000 0000
0000 0000
0000 0000
uuuu uuuu
EEA
--xx xxxx
--xx xxxx
--xx xxxx
--uu uuuu
EED
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
EEC
---- 0000
---- 0000
---- 0000
---- uuuu
FC0
0 111 0 0 0 0
0 111 0 0 0 0
0 111 0 0 0 0
uuuu uuuu
FC1
0000 0000
0000 0000
0000 0000
uuuu uuuu
FC2
---- ---0
---- ---0
---- ---0
---- ---u
FARL
0000 0000
0000 0000
0000 0000
uuuu uuuu
FARH
0000 0000
0000 0000
0000 0000
uuuu uuuu
Register
FD0L
0000 0000
0000 0000
0000 0000
uuuu uuuu
FD0H
0000 0000
0000 0000
0000 0000
uuuu uuuu
FD1L
0000 0000
0000 0000
0000 0000
uuuu uuuu
FD1H
0000 0000
0000 0000
0000 0000
uuuu uuuu
FD2L
0000 0000
0000 0000
0000 0000
uuuu uuuu
FD2H
0000 0000
0000 0000
0000 0000
uuuu uuuu
FD3L
0000 0000
0000 0000
0000 0000
uuuu uuuu
FD3H
0000 0000
0000 0000
0000 0000
uuuu uuuu
SGC
0--0 ----
0--0 ----
0--0 ----
u--u ----
SGN
--00 0000
--00 0000
--00 0000
--uu uuuu
SGDNR
---0 0000
---0 0000
---0 0000
---u uuuu
OPAC
0--- 0000
0--- 0000
0--- 0000
u--- uuuu
SWC
0000 0000
0000 0000
0000 0000
uuuu uuuu
DACO
--00 0000
--00 0000
--00 0000
--uu uuuu
FTRC
0--0 --00
0--0 --00
0--0 --00
u--u --uu
Note: "u" stands for unchanged
"x" stands for unknown
"-" stands for unimplemented
Rev. 1.10
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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 device provides 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
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
PBPU
—
—
—
D4
D3
D2
D1
D0
PB
—
—
—
D4
D3
D2
D1
D0
PBC
—
—
—
D4
D3
D2
D1
D0
PCPU
D7
D6
D5
D4
D3
D2
D1
—
PC
D7
D6
D5
D4
D3
D2
D1
—
PCC
D7
D6
D5
D4
D3
D2
D1
—
PDPU
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
PEPU
D7
D6
D5
D4
D3
D2
D1
D0
PE
D7
D6
D5
D4
D3
D2
D1
D0
PEC
D7
D6
D5
D4
D3
D2
D1
D0
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 PAPU~PEPU, and are implemented using weak
PMOS transistors.
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
Rev. 1.10
Port A bit 7 ~ bit 0 Pull-high Control
0: Disable
1: Enable
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PBPU Register
Bit
7
6
5
4
3
2
1
0
Name
—
—
—
D4
D3
D2
D1
D0
R/W
—
—
—
R/W
R/W
R/W
R/W
R/W
POR
—
—
—
0
0
0
0
0
3
2
1
0
Bit 7~5
Unimplemented, read as "0"
Bit 4~0
Port B bit 4 ~ bit 0 Pull-high Control
0: Disable
1: Enable
PCPU Register
Bit
7
6
5
4
Name
D7
D6
D5
D4
D3
D2
D1
—
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
—
POR
0
0
0
0
0
0
0
—
Bit 7~1
Port C bit 7 ~ bit 1 Pull-high Control
0: Disable
1: Enable
Bit 0
Unimplemented, read as "0"
PDPU 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
Port D bit 7 ~ bit 0 Pull-high Control
0: Disable
1: Enable
PEPU 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
Rev. 1.10
Port E bit 7 ~ bit 0 Pull-high Control
0: Disable
1: Enable
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Port A 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 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 can be selected individually to have this wake-up feature
using the PAWU register.
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
Port A bit 7~bit 0 Wake-up Control
0: Disable
1: Enable
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
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
Bit 7~0
Rev. 1.10
7
Port A bit 7 ~ bit 0 Input/Output Control
0: Output
1: Input
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PBC Register
Bit
7
6
5
4
3
2
1
0
Name
—
—
—
D4
D3
D2
D1
D0
R/W
—
—
—
R/W
R/W
R/W
R/W
R/W
POR
—
—
—
1
1
1
1
1
3
2
1
0
Bit 7~5
Unimplemented, read as "0"
Bit 4~0
Port B bit 4 ~ bit 0 Input/Output Control
0: Output
1: Input
PCC Register
Bit
7
6
5
4
Name
D7
D6
D5
D4
D3
D2
D1
—
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
—
POR
1
1
1
1
1
1
1
—
Bit 7~1
Port C bit 7 ~ bit 1 Input/Output Control
0: Output
1: Input
Bit 0
Unimplemented, read as "0"
PDC 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
Bit 7~0
Port D bit 7 ~ bit 0 Input/Output Control
0: Output
1: Input
PEC 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
Bit 7~0
Rev. 1.10
Port E bit 7 ~ bit 0 Input/Output Control
0: Output
1: Input
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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.
   
   Generic Input/Output Structure
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.
Port A has the additional capability of providing wake-up functions. When the device is in the
SLEEP or IDLE Mode, various methods are available to wake the device up. One of these is a high
to low transition of any of the Port A pins. Single or multiple pins on Port A can be setup to have this
function.
Rev. 1.10
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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 Periodic TM sections.
Introduction
The device contains three TMs having a reference name of TM0, TM1 and TM2. Each individual
TM can be categorised as a certain type, namely Compact Type TM or Periodic Type TM. Although
similar in nature, the different TM types vary in their feature complexity. The common features to all
of the Compact and Periodic 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
PTM
Timer/Counter
√
√
I/P Capture
—
√
Compare Match Output
√
√
PWM Channels
1
1
Single Pulse Output
—
1
Edge
Edge
Duty or Period
Duty or Period
PWM Alignment
PWM Adjustment Period & Duty
TM Function Summary
TM0
TM1
TM2
10-bit CTM
10-bit PTM
10-bit PTM
TM Name/Type Reference
TM Operation
The two 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.
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 fSUB clock source or the external TCKn pin. 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.
Rev. 1.10
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TM Interrupts
The Compact Type and Periodic 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/PTMnC0 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 the CTRL0 register. 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 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.
TM0
TM1
TM2
Register
TP0_0, TP0_1
TP1_0, TP1_1
TP2_0, TP2_1
CTRL0
TM Output Pins
TM Input/Output Pin Control Registers
Selecting to have a TM input/output or whether to retain its other shared functions is implemented
using one register with a single bit in each register corresponding to a TM input/output pin. When
the TMn is enabled, if the corresponding pin is setup as a TM input/output, and the complimentary
output will be as a normal I/O pin.
CTRL0 Register
Bit
7
6
5
4
3
2
1
0
Name
—
—
—
—
—
TP2CPS
TP1CPS
TP0CPS
R/W
—
—
—
—
—
R/W
R/W
R/W
POR
—
—
—
—
—
0
0
0
Bit 7~3
Unimplemented, read as "0"
Bit 2TP2CPS: TP2_0, TP2_1 pin selection
0: TP2_0
1: TP2_1
When TM2 is enabled, the output function of TP2_0 is timer, then the TP2_1 is I/O,
and vice versa.
Rev. 1.10
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Bit 1TP1CPS: TP1_0, TP1_1 pin selection
0: TP1_0
1: TP1_1
When TM1 is enabled, the output function of TP1_0 is timer, then the TP1_1 is I/O,
and vice versa.
Bit 0TP0CPS: TP0_0, TP0_1 pin selection
0: TP0_0
1: TP0_1
When TM0 is enabled, the output function of TP0_0 is timer, then the TP0_1 is I/O,
and vice versa.
Programming Considerations
The TM Counter Registers and the Capture/Compare CCRA and CCRP registers, being 10-bit, all
have a low and high byte structure. The high bytes can be directly accessed, but as the low bytes
can only be accessed via an internal 8-bit buffer, reading or writing to these register pairs must be
carried out in a specific way. The important point to note is that data transfer to and from the 8-bit
buffer and its related low byte only takes place when a write or read operation to its corresponding
high byte is executed. As the CCRA and CCRP registers are implemented in the way shown in the
following diagram and accessing the register is carried out in a specific way described above, it
is recommended to use the "MOV" instruction to access the CCRA and CCRP low byte registers,
named TMxAL/PTMxAL and PTMxRPL, using the following access procedures. Accessing
the CCRA or CCRP low byte register without following these access procedures will result in
unpredictable values.
TM Counter Register (Read only)
TMxDL/
PTMxDL
TMxDH/
PTMxDH
8-bit Buffer
TMxAL/
PTMxAL
TMxAH/
PTMxAH
TM CCRA Register (Read/Write)
PTMxRPL PTMxRPH
TM CCRP Register (Read/Write)
Data
Bus
The following steps show the read and write procedures:
• Writing Data to CCRA or CCRP
♦♦
Step 1. Write data to Low Byte TMxAL/PTMxAL or PTMxRPL
––Note that here data is only written to the 8-bit buffer.
♦♦
Step 2. Write data to High Byte TMxAH/PTMxAH or PTMxRPH
––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 or CCRP
Rev. 1.10
♦♦
Step 1. Read data from the High Byte TMxDH/PTMxDH, TMxAH/PTMxAH or PTMxRPH
––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/PTMxDL, TMxAL/PTMxAL or PTMxRPL
––This step reads data from the 8-bit buffer.
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Compact Type TM – CTM
Although the simplest form of the two TM types, the Compact TM type still contains three operating
modes, which are Compare Match Output, Timer/Event Counter and PWM Output modes. The
Compact TM can 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.
Name
TM No.
TM Input Pin
TM Output Pin
10-bit CTM
0
TCK0
TP0_0, TP0_1
Compact TM Operation
At its core is a 10-bit count-up counter which is driven by a user selectable internal or external clock
source. There are also two internal comparators with the names, Comparator A and Comparator
P. These comparators will compare the value in the counter with CCRP and CCRA registers. The
CCRP is three bits wide whose value is compared with the highest three bits in the counter while the
CCRA is the ten bits and therefore compares with all counter bits.
The only way of changing the value of the 10-bit counter using the application program, is to
clear the counter by changing the TnON bit from low to high. The counter will also be cleared
automatically by a counter overflow or a compare match with one of its associated comparators.
When these conditions occur, a TM interrupt signal will also usually be generated. The Compact
Type TM can operate in a number of different operational modes, can be driven by different clock
sources including an input pin and can also control an output pin. All operating setup conditions are
selected using relevant internal registers.
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  ­ ­     Compact Type TM Block Digram (n=0)
Rev. 1.10
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Body Fat Scale 8-Bit Flash MCU
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=0)
TMnC0 Register (n=0)
Bit
7
6
5
4
3
2
1
0
Name
TnPAU
TnCK2
TnCK1
TnCK0
TnON
TnRP2
TnRP1
TnRP0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
0
0
0
0
0
0
0
Bit 7TnPAU: TMn Counter Pause Control
0: Run
1: Pause
The counter can be paused by setting this bit high. Clearing the bit to zero restores
normal counter operation. When in a Pause condition the TM will remain powered up
and continue to consume power. The counter will retain its residual value when this bit
changes from low to high and resume counting from this value when the bit changes
to a low value again.
Bit 6~4TnCK2~TnCK0: Select TMn Counter clock
000: fSYS/4
001: fSYS
010: fH/16
011: fH/64
100: fSUB
101: Reserved
110: TCKn rising edge clock
111: TCKn 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 fSUB are other internal clocks, the details of which can be
found in the oscillator section.
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Bit 3TnON: TMn 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. 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 TnOC bit, when the
TnON bit changes from low to high.
Bit 2~0TnRP2~TnRP0: TMn CCRP 3-bit register, compared with the TMn Counter bit 9~bit
7 Comparator P Match Period
000: 1024 TMn clocks
001: 128 TMn clocks
010: 256 TMn clocks
011: 384 TMn clocks
100: 512 TMn clocks
101: 640 TMn clocks
110: 768 TMn clocks
111: 896 TMn clocks
These three bits are used to setup the value on the internal CCRP 3-bit register, which
are then compared with the internal counter’s highest three bits. The result of this
comparison can be selected to clear the internal counter if the TnCCLR bit is set to
zero. Setting the TnCCLR bit to zero ensures that a compare match with the CCRP
values will reset the internal counter. As the CCRP bits are only compared with the
highest three counter bits, the compare values exist in 128 clock cycle multiples.
Clearing all three bits to zero is in effect allowing the counter to overflow at its
maximum value.
TMnC1 Register (n=0)
Bit
7
6
5
4
3
2
1
0
Name
TnM1
TnM0
TnIO1
TnIO0
TnOC
TnPOL
TnDPX
TnCCLR
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
0
0
0
0
0
0
0
Bit 7~6TnM1~TnM0: Select TMn Operating Mode
00: Compare Match Output Mode
01: Undefined
10: PWM Mode
11: Timer/Counter Mode
These bits setup the required operating mode for the TM. To ensure reliable operation
the TM should be switched off before any changes are made to the TnM1 and TnM0
bits. In the Timer/Counter Mode, the TM output pin control must be disabled.
Bit 5~4TnIO1~TnIO0: Select TPn_0, TPn_1 output function
Compare Match Output Mode
00: No change
01: Output low
10: Output high
11: Toggle output
PWM Mode
00: PWM Output inactive state
01: PWM Output active state
10: PWM output
11: Undefined
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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 TnIO1 and TnIO0 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 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 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 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.
Bit 3TnOC: TPn_0, TPn_1 Output control bit
Compare Match Output Mode
0: Initial low
1: Initial high
PWM Mode
0: Active low
1: Active high
This is the output control bit for the TM output pin. Its operation depends upon whether
TM is being used in the Compare Match Output Mode or in the PWM 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 2TnPOL: TPn_0, TPn_1 Output polarity Control
0: Non-invert
1: Invert
This bit controls the polarity of the TPn_0 or TPn_1 output pin. When the bit is set
high the 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 1TnDPX: TMn PWM period/duty Control
0: CCRP - period; CCRA - duty
1: CCRP - duty; CCRA - period
This bit, determines which of the CCRA and CCRP registers are used for period and
duty control of the PWM waveform.
Bit 0TnCCLR: Select TMn Counter clear condition
0: TMn Comparatror P match
1: TMn Comparatror A match
This bit is used to select the method which clears the counter. Remember that the
Compact TM 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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TMnDL Register (n=0)
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 7~0D7~D0: TMn Counter Low Byte Register bit 7 ~ bit 0
TMn 10-bit Counter bit 7 ~ bit 0
TMnDH Register (n=0)
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 1~0D9~D8: TMn Counter High Byte Register bit 1 ~ bit 0
TMn 10-bit Counter bit 9 ~ bit 8
TMnAL Register (n=0)
Bit
7
6
5
4
3
2
1
0
Name
D7
D6
D5
D4
D3
D2
D1
D0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
0
0
0
0
0
0
0
2
1
0
Bit 7~0D7~D0: TMn CCRA Low Byte Register bit 7 ~ bit 0
TMn 10-bit CCRA bit 7 ~ bit 0
TMnAH Register (n=0)
Bit
7
6
5
4
3
Name
—
—
—
—
—
—
D9
D8
R/W
—
—
—
—
—
—
R/W
R/W
POR
—
—
—
—
—
—
0
0
Bit 7~2
Unimplemented, read as "0"
Bit 1~0D9~D8: TMn CCRA High Byte Register bit 1 ~ bit 0
TMn 10-bit CCRA bit 9 ~ bit 8
Rev. 1.10
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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 an 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.
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Co�nte� Val�e
Co�nte� ove�flow
CCRP=0
0x3FF
TnCCLR = 0; TnM [1:0] = 00
CCRP > 0
Co�nte� clea�ed b� CCRP val�e
CCRP > 0
Co�nte�
Resta�t
Res�me
CCRP
Pa�se
CCRA
Stop
Time
TnON
TnPAU
TnPOL
CCRP Int.
Flag TnPF
CCRA Int.
Flag TnAF
TM O/P Pin
O�tp�t pin set to
initial Level Low
if TnOC=0
O�tp�t not affected b� TnAF
flag. Remains High �ntil �eset
b� TnON bit
O�tp�t Toggle with
TnAF flag
He�e TnIO [1:0] = 11
Toggle O�tp�t select
Note TnIO [1:0] = 10
Active High O�tp�t select
O�tp�t Inve�ts
when TnPOL is high
O�tp�t Pin
Reset to Initial val�e
O�tp�t cont�olled b�
othe� pin-sha�ed f�nction
Compare Match Output Mode – TnCCLR = 0 (n=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. 1.10
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Body Fat Scale 8-Bit Flash MCU
Co�nte� Val�e
TnCCLR = 1; TnM [1:0] = 00
CCRA = 0
Co�nte� ove�flow
CCRA > 0 Co�nte� clea�ed b� CCRA val�e
0x3FF
CCRA=0
Res�me
CCRA
Pa�se
Stop
Co�nte� Resta�t
CCRP
Time
TnON
TnPAU
TnPOL
No TnAF flag
gene�ated on
CCRA ove�flow
CCRA Int.
Flag TnAF
CCRP Int.
Flag TnPF
TnPF not
gene�ated
O�tp�t does
not change
TM O/P Pin
O�tp�t pin set to
initial Level Low
if TnOC=0
O�tp�t not affected b�
TnAF flag. Remains High
�ntil �eset b� TnON bit
O�tp�t Toggle with
TnAF flag
He�e TnIO [1:0] = 11
Toggle O�tp�t select
Note TnIO [1:0] = 10
Active High O�tp�t select
O�tp�t Inve�ts
when TnPOL is high
O�tp�t Pin
Reset to Initial val�e
O�tp�t cont�olled b�
othe� pin-sha�ed f�nction
Compare Match Output Mode – TnCCLR = 1 (n=0)
Note: 1. With TnCCLR=1, a Comparator A match will clear the counter
2. The TM output pin is controlled only by the TnAF flag
3. The output pin is reset to its initial state by a TnON bit rising edge
4. The TnPF flag is not generated when TnCCLR=1
Rev. 1.10
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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.
PWM Output Mode
To select this mode, bits TnM1 and TnM0 in the TMnC1 register should be set to 10 respectively.
The PWM function within the TM is useful for applications which require functions such as motor
control, heating control, illumination control etc. By providing a signal of fixed frequency but
of varying duty cycle on the TM output pin, a square wave AC waveform can be generated with
varying equivalent DC RMS values.
As both the period and duty cycle of the PWM waveform can be controlled, the choice of generated
waveform is extremely flexible. In the PWM mode, the TnCCLR bit has no effect on the PWM
operation. Both of the CCRA and CCRP registers are used to generate the PWM waveform, one
register is used to clear the internal counter and thus control the PWM waveform frequency, while
the other one is used to control the duty cycle. Which register is used to control either frequency
or duty cycle is determined using the TnDPX bit in the TMnC1 register. The PWM waveform
frequency and duty cycle can therefore be controlled by the values in the CCRA and CCRP registers.
An interrupt flag, one for each of the CCRA and CCRP, will be generated when a compare match
occurs from either Comparator A or Comparator P. The TnOC bit in the TMnC1 register is used to
select the required polarity of the PWM waveform while the two TnIO1 and TnIO0 bits are used to
enable the PWM output or to force the TM output pin to a fixed high or low level. The TnPOL bit is
used to reverse the polarity of the PWM output waveform.
• CTM, PWM Mode, Edge-aligned Mode, TnDPX=0
CCRP
001b
010b
011b
100b
101b
110b
111b
000b
Period
128
256
384
512
640
768
896
1024
Duty
CCRA
If fSYS = 16MHz, TM clock source is fSYS/4, CCRP = 100b and CCRA = 128,
The CTM PWM output frequency = (fSYS/4)/512 = fSYS/2048 = 7.8125 kHz, duty = 128/512 = 25%.
If the Duty value defined by the CCRA register is equal to or greater than the Period value, then the
PWM output duty is 100%.
• CTM, PWM Mode, Edge-aligned Mode, TnDPX=1
CCRP
001b
010b
011b
100b
128
256
384
512
Period
Duty
101b
110b
111b
000b
768
896
1024
CCRA
640
The PWM output period is determined by the CCRA register value together with the TM clock
while the PWM duty cycle is defined by the CCRP register value.
Rev. 1.10
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Co�nte� Val�e
TnDPX = 0; TnM [1:0] = 10
Co�nte� clea�ed
b� CCRP
Co�nte� Reset when
TnON �et��ns high
CCRP
Pa�se Res�me
CCRA
Co�nte� 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 D�t� C�cle
set b� CCRA
PWM Pe�iod
set b� CCRP
PWM �es�mes
ope�ation
O�tp�t cont�olled b�
O�tp�t Inve�ts
othe� pin-sha�ed f�nction
when TnPOL = 1
PWM Mode – TnDPX = 0 (n=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. 1.10
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Co�nte� Val�e
TnDPX = 1; TnM [1:0] = 10
Co�nte� clea�ed
b� CCRA
Co�nte� Reset when
TnON �et��ns high
CCRA
Pa�se Res�me
CCRP
Co�nte� 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 D�t� C�cle
set b� CCRP
PWM Pe�iod
set b� CCRA
PWM �es�mes
ope�ation
O�tp�t cont�olled b�
O�tp�t Inve�ts
othe� pin-sha�ed f�nction
when TnPOL = 1
PWM Mode – TnDPX = 1 (n=0)
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. 1.10
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Periodic Type TM – PTM
The Periodic Type TM contains five operating modes, which are Compare Match Output, Timer/
Event Counter, Capture Input, Single Pulse Output and PWM Output modes. The Periodic TM can
be controlled with an external input pin and can drive two external output pin.
Name
TM No.
TM Input Pin
TM Output Pin
10-bit PTM
1, 2
TCK1, TCK2
TP1_0, TP1_1
TP2_0, TP2_1
Periodic 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 two internal comparators with the names, Comparator A and Comparator P. These
comparators will compare the value in the counter with the CCRA and CCRP registers.
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 Periodic
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 the output pin. All operating setup conditions are
selected using relevant internal registers.
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Periodic Type TM Block Diagram (n=1 or 2)
Rev. 1.10
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Periodic Type TM Register Description
Overall operation of the Periodic TM is controlled using a series of registers. A read only register
pair exists to store the internal counter 10-bit value, while two read/write register pairs exist to store
the internal 10-bit CCRA and CCRP value. The remaining two registers are control registers which
setup the different operating and control modes.
Bit
Register
Name
7
6
5
4
3
2
1
0
PTMnC0
TnPAU
TnCK2
TnCK1
TnCK0
TnON
—
—
—
PTMnC1
TnM1
TnM0
TnIO1
TnIO0
TnOC
TnPOL
TnCAPTS
TnCCLR
PTMnDL
D7
D6
D5
D4
D3
D2
D1
D0
PTMnDH
—
—
—
—
—
—
D9
D8
PTMnAL
D7
D6
D5
D4
D3
D2
D1
D0
PTMnAH
—
—
—
—
—
—
D9
D8
PTMnRPL
D7
D6
D5
D4
D3
D2
D1
D0
PTMnRPH
—
—
—
—
—
—
D9
D8
10-bit Periodic TM Register List (n=1 or 2)
PTMnC0 Register (n=1 or 2)
Bit
7
6
5
4
3
2
1
0
Name
TnPAU
TnCK2
TnCK1
TnCK0
TnON
—
—
—
R/W
R/W
R/W
R/W
R/W
R/W
—
—
—
POR
0
0
0
0
0
—
—
—
Bit 7TnPAU: TMn Counter Pause Control
0: Run
1: Pause
The counter can be paused by setting this bit high. Clearing the bit to zero restores
normal counter operation. When in a Pause condition the TM will remain powered up
and continue to consume power. The counter will retain its residual value when this bit
changes from low to high and resume counting from this value when the bit changes
to a low value again.
Bit 6~4TnCK2~TnCK0: Select TMn Counter clock
000: fSYS/4
001: fSYS
010: fH/16
011: fH/64
100: fSUB
101: Reserved
110: TCKn rising edge clock
111: TCKn 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 fSUB are other internal clocks, the details of which can be
found in the oscillator section.
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Bit 3TnON: TMn 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 TM Output control bit, when the bit changes
from low to high.
Bit 2~0
Unimplemented, read as "0"
PTMnC1 Register (n=1 or 2)
Bit
7
6
5
4
3
2
1
0
Name
TnM1
TnM0
TnIO1
TnIO0
TnOC
TnPOL
TnCAPTS
TnCCLR
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
0
0
0
0
0
0
0
Bit 7~6TnM1~TnM0: Select TMn Operation 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 TnM1 and TnM0
bits. In the Timer/Counter Mode, the TM output pin control must be disabled.
Bit 5~4TnIO1~TnIO0: Select TPn_0, TPn_1 output function
Compare Match Output Mode
00: No change
01: Output low
10: Output high
11: Toggle output
PWM Mode/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 TPn_0, TPn_1, TCKn
01: Input capture at falling edge of TPn_0, TPn_1, TCKn
10: Input capture at falling/rising edge of TPn_0, TPn_1, TCKn
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 TnIO1 and TnIO0 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 these 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 TnOC bit. Note that the output level requested by the TnIO1
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and TnIO0 bits must be different from the initial value setup using the TnOC 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 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 change the values
of the TnIO1 and TnIO0 bits only after the TM has been switched off. Unpredictable
PWM outputs will occur if the TnIO1 and TnIO0 bits are changed when the TM is
running.
Bit 3TnOC: TPn_0, TPn_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 2TnPOL: TPn_0, TPn_1 Output polarity Control
0: Non-invert
1: Invert
This bit controls the polarity of the TPn_0, TPn_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 1TnCAPTS: TMn capture trigger source select
0: From TPn_0, TPn_1 pin
1: From TCKn pin
Bit 0TnCCLR: Select TMn Counter clear condition
0: TMn Comparatror P match
1: TMn Comparatror A match
This bit is used to select the method which clears the counter. Remember that the
Periodic TM 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, Single Pulse or Input Capture Mode.
PTMnDL Register (n=1 or 2)
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 7~0PTMnDL: TMn Counter Low Byte Register bit 7 ~ bit 0
TMn 10-bit Counter bit 7 ~ bit 0
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PTMnDH Register (n=1 or 2)
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 1~0PTMnDH: TMn Counter High Byte Register bit 1 ~ bit 0
TMn 10-bit Counter bit 9 ~ bit 8
PTMnAL Register (n=1 or 2)
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 7~0PTMnAL: TMn CCRA Low Byte Register bit 7 ~ bit 0
TMn 10-bit CCRA bit 7 ~ bit 0
PTMnAH Register (n=1 or 2)
Bit
7
6
5
4
3
2
1
0
Name
—
—
—
—
—
—
D9
D8
R/W
—
—
—
—
—
—
R/W
R/W
POR
—
—
—
—
—
—
0
0
Bit 7~2
Unimplemented, read as "0"
Bit 1~0PTMnAH: TMn CCRA High Byte Register bit 1 ~ bit 0
TMn 10-bit CCRA bit 9 ~ bit 8
PTMnRPL Register (n=1 or 2)
Bit
7
6
5
4
3
2
1
0
Name
D7
D6
D5
D4
D3
D2
D1
D0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
0
0
0
0
0
0
0
2
1
0
Bit 7~0PTMnRPL: TMn CCRP Low Byte Register bit 7 ~ bit 0
TMn 10-bit CCRP bit 7 ~ bit 0
PTMnRPH Register (n=1 or 2)
Bit
7
6
5
4
3
Name
—
—
—
—
—
—
D9
D8
R/W
—
—
—
—
—
—
R/W
R/W
POR
—
—
—
—
—
—
0
0
Bit 7~2
Unimplemented, read as "0"
Bit 1~0PTMnRPH: TMn CCRP High Byte Register bit 1 ~ bit 0
TMn 10-bit CCRP bit 9 ~ bit 8
Rev. 1.10
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Periodic Type TM Operating Modes
The Periodic 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 PTMnC1 register.
Compare Match Output Mode
To select this mode, bits TnM1 and TnM0 in the PTMnC1 register, should be all cleared 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 the TnAF and TnPF interrupt request
flags for Comparator A and Comparator P respectively, will both be generated.
If the TnCCLR bit in the PTMnC1 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 cleared to zero.
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 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 PTMnC1 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, TnIO0 bits are zero then no
pin change will take place.
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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 (n=1 or 2)
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 initial state by a TnON bit rising edge
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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 (n=1 or 2)
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 initial state by a TnON rising edge
4. The TnPF flag is not generated when TnCCLR = 1
Rev. 1.10
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Timer/Counter Mode
To select this mode, bits TnM1 and TnM0 in the PTMnC1 register should all 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 PTMnC1 register should be set to 10 respectively
and also the TnIO1 and TnIO0 bits should be set to 10 respectively. The PWM function within
the TM is useful for applications which require functions such as motor control, heating control,
illumination control etc. By providing a signal of fixed frequency but of varying duty cycle on the
TM output pin, a square wave AC waveform can be generated with varying equivalent DC RMS
values.
As both the period and duty cycle of the PWM waveform can be controlled, the choice of generated
waveform is extremely flexible. In the PWM mode, the TnCCLR bit has no effect as the PWM
period. Both of the CCRP and CCRA 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. 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 PTMnC1 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.
• 10-bit PTM, PWM Mode
CCRP
0
Period
1024
Duty
1~1023
1~1023
CCRA
If fSYS = 16MHz, TM clock source select fSYS/4, CCRP = 100b and CCRA = 128,
The PTM 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%.
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Counter Value
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 (n=1 or 2)
Note: 1. Here Counter cleared by CCRP
2. A counter clear sets the PWM Period
3. The internal PWM function continues running even when TnIO[1:0] = 00 or 01
4. The TnCCLR bit has no influence on PWM operation
Rev. 1.10
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Single Pulse Output Mode
To select this mode, the required bit pairs, TnM1 and TnM0 should be set to 10 respectively and also
the corresponding TnIO1 and TnIO0 bits should be set to 11 respectively. The Single Pulse Output
Mode, as the name suggests, will generate a single shot pulse on the TM output pin.
The trigger for the pulse output leading edge is a low to high transition of the TnON bit, which can
be implemented using the application program. However in the Single Pulse Mode, the TnON bit
can also be made to automatically change from low to high using the external TCKn pin, which will
in turn initiate the Single Pulse output. When the TnON bit transitions to a high level, the counter
will start running and the pulse leading edge will be generated. The TnON bit should remain high
when the pulse is in its active state. The generated pulse trailing edge will be generated when the
TnON bit is cleared to zero, which can be implemented using the application program or when a
compare match occurs from Comparator A.
However a compare match from Comparator A will also automatically clear the TnON bit and thus
generate the Single Pulse output trailing edge. In this way the CCRA value can be used to control the
pulse width. A compare match from Comparator A will also generate TM interrupts. 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 bit is also not used.
            Single Pulse Generation (n=1 or 2)
Rev. 1.10
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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
Clear
Software
Trigger
Software
Trigger
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 (n=1 or 2)
Note: 1. Counter stopped by CCRA
2. CCRP is not used
3. The pulse is triggered by the TCKn pin or by setting the TnON bit high
4. A TCKn pin active edge will automatically set the TnON bit high
5. In the Single Pulse Mode, TnIO [1:0] must be set to "11" and cannot be changed.
Rev. 1.10
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Capture Input Mode
To select this mode bits TnM1 and TnM0 in the PTMnC1 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, TPn_1 or TCKn pin, selected by the TnCAPTS bit in the PTMnC1 register.
The input pin 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 PTMnC1 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, TPn_1 or TCKn pin the present value in
the counter will be latched into the CCRA register and a TM interrupt generated. Irrespective of
what events occur on the TPn_0, TPn_1 or TCKn 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, TPn_1
or TCKn 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,
TPn_1 or TCKn pin, however it must be noted that the counter will continue to run.
As the TPn_0, TPn_1 or TCKn pin is pin shared with other functions, care must be taken if the TMn
is in the Capture Input 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, TnOC and TnPOL bits
are not used in this Mode.
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Counter Value
TnM [1:0] = 01
Counter cleared
by CCRP
Counter Counter
Reset
Stop
CCRP
YY
Pause
Resume
XX
Time
TnON
TnPAU
TM capture pin
TPn_x or TCKn
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 (n=1 or 2)
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 counter value to CCRA
3. The TnCCLR bit is not used
4. No output function – TnOC and TnPOL bits are not used
5. CCRP determines the counter value and the counter has a maximum count value when
CCRP is equal to zero
Rev. 1.10
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Internal Power Supply
This device contains the LDO and VCM for the regulated power supply. The accompanying
block diagram illustrates the basic functional operation. The internal LDO can provide the fixed
voltage for PGA, ADC or the external components; as well the VCM can be used as the reference
voltage for ADC module. There are four LDO voltage levels, 2.4V, 2.6V, 2.9V or 3.3V, decided by
LDOVS1~LDOVS0 bits in the PWRC register, as well the VCM has two output voltage levels,
1.05V or 1.25V, selected by the VCMS bit in the PGAC1 register. The LDO and VCM functions
can be controlled by the ENLDO and ENVCM bits respectively and can be powered off to reduce
the power consumption. In addition, the LDO bypass function can be enabled or disabled by the
LDOBPS bit in the register.
VDD
LDOBPS
B�pass
LDO
VOUT/AVDD
Fo� senso� powe�
�.4
�.6
�.6
3.3
Fo� PGA� ADC powe�
ENLDO
LDOVS[1:0]
ENVCM
PGA
VCM
VCM
1.0�
1.��
Analog common mode voltage
1.0�V o� 1.��V
VCMS
Registers
ADOFF
Output Voltage
ENLDO
ENVCM
VOUT/AVDD
VCM
1
0
×
Disable
Disable
1
1
×
Enable
Disable
0
0
0
Disable
Disable
0
1
0
Enable
Disable
0
0
1
Disable
Disable
0
1
1
Enable
Enable
"x" means don’t care
Power Control Table
Rev. 1.10
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PWRC Register
Bit
7
6
5
4
3
2
1
0
Name
ENLDO
ENVCM
—
—
—
LDOBPS
LDOVS1
LDOVS0
R/W
R/W
R/W
—
—
—
R/W
R/W
R/W
POR
0
0
—
—
—
0
0
0
Bit 7ENLDO: LDO function control bit
0: Disable
1: Enable
If the LDO is disabled, there will be no power consumption and LDO output pin is
floating.
Bit 6ENVCM: VCM function control bit
0: Disable
1: Enable
If the VCM is disabled, there will be no power consumption and VCM output pin is
floating.
Bit 5~3
Unimplemented, read as "0"
Bit 2LDOBPS: LDO Bypass function control bit
0: Disable
1: Enable
Bit 1~0LDOVS1~LDOVS0: LDO output voltage selection
00: 2.4V
01: 2.6V
10: 2.9V
11: 3.3V
PGAC1 Register
Bit
7
6
5
4
3
2
1
0
Name
VCMS
INIS
—
—
DCSET2
DCSET1
DCSET0
—
R/W
R/W
R/W
—
—
R/W
R/W
R/W
—
POR
1
0
—
—
0
0
0
—
Bit 7VCMS: Analog Common mode voltage selection
0: 1.05V
1: 1.25V
Bit 6INIS: The selected input ends, IN1 and IN2, connection control bit
Described elsewhere.
Bit 5~4
Unimplemented, read as "0"
Bit 3~1DCSET2~DCSET0: The DI+/DI- differential input offset voltage adjustment control
Described elsewhere.
Bit 0
Rev. 1.10
Unimplemented, read as "0"
103
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Analog to Digital Converter – ADC
The need to interface to real world analog signals is a common requirement for many electronic
systems. However, to properly process these signals by a microcontroller, they must first be
converted into digital signals by A/D converters. By integrating the A/D conversion electronic
circuitry into the microcontroller, the need for external components is reduced significantly with the
corresponding follow-on benefits of lower costs and reduced component space requirements.
A/D Data Rate Definition
The delta-sigma ADC data rate can be calculated by the equation list below:
Data Rate = (ADC clock) / (FLMS[2:0] × ADOR[2:0])
Where ADC clock comes from fMCLK, and FLMS[2:0] select ADC mode and define a constant
number which can only be 30 or 12, finally ADOR[2:0] define chopper average function and OverSampling Rating (OSR).
For example, if a data rate of 10Hz is desired. You can have a 4.8MHz ADC clock, then set
FLMS[2:0] = 000b (ADC output in normal mode and clock divided by 30); finally set ADOR[2:0] =
001b to define chopper = 2 and OSR = 8192.
Thus Data Rate = 4.8MHz / (30 × 2 × 8192) = 10Hz
In addition, the A/D converter can provide a data rate of 3.2kHz to use for auto power on.
A/D Overview
This device contains a high accuracy multi-channel 20-bit delta-sigma analog-to-digital (ΔΣA/D)
converter which can directly interface to external analog signals, such as that from sensors or other
control signals and convert these signals directly into a 20-bit digital value.
In addition, the PGA gain control, ADC gain control and ADC reference gain control determine
the amplification gain for ADC input signal. The designer can select the best gain combination for
the desired amplification applied to the input signal. The following block diagram illustrates the
ADC basic operational function. The ADC input channel can be arranged as two differential input
channels. The input signal can be amplified by PGA before entering the 20-bit delta-sigma ADC.
The ΔΣADC modulator will output one bit converted data to SINC filter which can transform the
converted one-bit data to 20 bits and store them into the specific data registers. Additionally, this
device also provides a temperature sensor to compensate the A/D converter deviation caused by the
temperature. With high accuracy and performance, this device is very suitable for the Weight Scale
related products.
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AN0
000
AN2
001
RFC
101
VCM
110
VTSO+
111
IN1
VCM
DI+
CHSP[2:0]
INIS
DI-
AN1
000
AN3
001
20-bit ADC
PGS=x1,x2,x4,x8,
x16,x32,x64,x128
AGS= x1, x2, x4, x8
101
VCM
110
VTSO-
111
SINC Filter
VGS= x1, x1/2, x1/4
REFP
REFN
Buffer
VRBUFP
IN2
VDD/5
ADRST
ADOR[2:0]
DCSET[2:0]
VRP
VRBUFN
VRN
0
1
0
1
VREFS
CHSN[2:0]
VCM
AVSS
VREFP
VREFN
A/D Converter Structure
A/D Converter Register Description
Overall operation of the A/D converter is controlled by using 9 registers. A group of read only
registers exist to store the ADC data 20-bit value. The remaining 6 registers are control registers
which set up the gain selections and control functions of the A/D converter.
Bit
Register
Name
7
6
5
4
3
2
1
0
PGAC0
—
VGS1
VGS0
AGS1
AGS0
PGS2
PGS1
PGS0
PGAC1
VCMS
INIS
—
—
DCSET2
DCSET1
DCSET0
—
PGACS
—
—
CHSN2
CHSN1
CHSN0
CHSP2
CHSP1
CHSP0
ADRL
D7
D6
D5
D4
D3
D2
D1
D0
ADRM
D15
D14
D13
D12
D11
D10
D9
D8
ADRH
—
—
—
—
D19
D18
D17
D16
ADCR0
ADRST
ADSLP
ADOFF
ADOR2
ADOR1
ADOR0
—
VREFS
ADCR1
FLMS2
FLMS1
FLMS0
ADCS
—
—
—
VRBUFN VRBUFP
ADCK4
ADCK3
ADCDL
EOC
—
ADCK2
ADCK1
ADCK0
A/D Converter Register List
Programmable Gain Amplifier – PGA
There are three registers related to the programmable gain control, PGAC0, PGAC1 and PGACS.
The PGAC0 resister is used to select the PGA gain, ADC gain and the ADC reference gain. As
well, the PGAC1 register is used to define the input connection, differential input offset voltage
adjustment control and the VCM voltage selection. In addition, The PGACS register is used to select
the input ends for the PGA. Therefore, the input channels have to be determined by the CHSP2~0
and CHSN2~0 bits to determine which analog channel input pins, RFC pin, temperature detector
inputs or internal power supply are actually connected to the internal differential A/D converter.
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PGAC0 Register
Bit
7
6
5
4
3
2
1
0
Name
—
VGS1
VGS0
AGS1
AGS0
PGS2
PGS1
PGS0
R/W
—
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
—
0
0
0
0
0
0
0
Bit 7
Unimplemented, read as "0"
Bit 6~5VGS1~VGS0: VREF gain selection
00: 1
01: 1/2
10: 1/4
11: Reserved
Bit 4~3AGS1~AGS0: ADC gain selection
00: 1
01: 2
10: 4
11: 8
Bit 2~0PGS2~PGS0: PGA gain selection
000: 1
001: 2
010: 4
011: 8
100: 16
101: 32
110: 64
111: 128
PGAC1 Register
Bit
7
6
5
4
3
2
1
0
Name
VCMS
INIS
—
—
DCSET2
DCSET1
DCSET0
—
R/W
R/W
R/W
—
—
R/W
R/W
R/W
—
POR
1
0
—
—
0
0
0
—
Bit 7VCMS: Analog Common mode voltage selection
0: 1.05V
1: 1.25V
Bit 6INIS: The selected input ends, IN1 and IN2, connection control bit
0: Not shorted
1: Shorted
Bit 5~4
Unimplemented, read as "0"
Bit 3~1DCSET2~DCSET0: The DI+/DI- differential input offset voltage adjustment control
000: +0V
001: +0.25VR
010: +0.5VR
011: +0.75VR
100: +0V
101: -0.25VR
110: -0.5VR
111: -0.75VR
Bit 0
Rev. 1.10
Unimplemented, read as "0"
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PGACS Register
Bit
7
6
5
4
3
2
1
0
Name
—
—
CHSN2
CHSN1
CHSN0
CHSP2
CHSP1
CHSP0
R/W
—
—
R/W
R/W
R/W
R/W
R/W
R/W
POR
—
—
0
0
0
0
0
0
Bit 7~6
Unimplemented, read as "0"
Bit 5~3CHSN2~CHSN0: PGA negative input ends selection
000: AN1
001: AN3
010: Reserved
011: Reserved
100: Reserved
101: VDD/5
110: VCM
111: Temperature sensor VTSOBit 2~0CHSP2~CHSP0: PGA positive input ends selection
000: AN0
001: AN2
010: Reserved
011: Reserved
100: Reserved
101: RFC — The RFC is a single-end input, if selected, then the PGA negative input must be chosen the VCM, AN1 or AN3.
110: VCM
111: Temperature sensor VTSO+
Note: If the PGA is assigned the single end input to DI+, then the DI- input must be
selected the VCM.
A/D Converter Data Registers – ADRL, ADRM, ADRH
This device contains an internal 20-bit ΔΣA/D converter, it requires three data registers to store the
converted value. These are a high byte register, known as ADRH, ADRM and a low byte register,
known as ADRL. After the conversion process takes place, these registers can be directly read by the
microcontroller to obtain the digitised conversion value. D0~D19 are the A/D conversion result data
bits.
ADRH Register
Bit
7
6
5
4
3
2
1
0
Name
—
—
—
—
D19
D18
D17
D16
R/W
—
—
—
—
R
R
R
R
POR
—
—
—
—
×
×
×
×
"x" unknown
Rev. 1.10
Bit 7~4
Unimplemented, read as "0"
Bit 3~0
A/D conversion data Register bit 19~bit 16
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ADRM 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
×
×
×
×
×
×
×
×
Bit 7~0
"x" unknown
A/D conversion data Register bit 15~bit 8
ADRL 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
×
×
×
×
×
×
×
×
Bit 7~0
"x" unknown
A/D conversion data Register bit 7~bit 0
A/D Converter Control Registers – ADCR0, ADCR1, ADCS
To control the function and operation of the A/D converter, three control registers known as ADCR0,
ADCR1 and ADCS are provided. These 8-bit registers define functions such as the selection of
which reference source is used to the internal ADC, the ADC clock source, the ADC output data rate
as well as controlling the power-up function and monitoring the ADC end of conversion status.
ADCR0 Register
Bit
7
6
5
4
3
2
1
0
Name
ADRST
ADSLP
ADOFF
ADOR2
ADOR1
ADOR0
—
VREFS
R/W
R/W
R/W
R/W
R/W
R/W
R/W
—
R/W
POR
0
0
1
0
0
0
—
0
ADRST: ADC software reset control bit.
0: Disable
1: Enable
This bit is used to reset the ADC internal digital SINC filter. The bit is normally low
but if set high and then cleared low again, the A/D converter will initiate a conversion
process data.
Bit 6ADSLP: ADC sleep mode control bit
0: Normal mode
1: Sleep mode
This bit is used for ADC sleep mode control bit. To set this bit high will force the ADC
enter sleep mode which can reduce the power consumption and prevent the ADC startup time.
Bit 5ADOFF: ADC module power on/off control bit
0: ADC module power on
1: ADC module power off
This bit controls the power of the ADC module. This bit should be cleared to zero
to enable the A/D converter. If the bit is set high then the ADC will be switched
off reducing the device power consumption. As the ADC will consume a limited
amount of power, even when not executing a conversion, this may be an important
consideration in power sensitive battery powered applications.
Note: 1. It is recommended to set ADOFF=1 before entering IDLE/SLEEP Mode for
saving power.
2. ADOFF=1 will power down the ADC module, no matter the settings of
ADSLP and ADRST bits.
3. The relationship about these bits, ADOFF, ADSLP, ADRST will be further
described elsewhere.
Bit 7
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Bit 4 ~ 2ADOR2~ADOR0: Output data rate selection
Normal Mode: Output Data Rate
000: CHOP = 2, OSR=16384
001: CHOP = 2, OSR=8192
010: CHOP = 2, OSR=4096
011: CHOP = 2, OSR=2048
100: CHOP = 2, OSR=1024
101: CHOP = 2, OSR=512
110: CHOP = 2, OSR=256
111: CHOP = 2, OSR=128
Low Latency Mode: Output Data Rate
000: CHOP = 1, OSR=16384
001: CHOP = 1, OSR=8192
010: CHOP = 1, OSR=4096
011: CHOP = 1, OSR=2048
100: CHOP = 1, OSR=1024
101: CHOP = 1, OSR=512
110: CHOP = 1, OSR=256
111: CHOP = 1, OSR=128
Bit 1
Unimplemented, read as "0"
Bit 0VREFS: ADC reference source selection
0: Internal reference (VCM, AVSS)
1: External reference (VREFP,VREFN)
ADCR1 Register
Bit
7
6
5
4
3
Name
FLMS2
FLMS1
FLMS0
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
0
0
0
0
VRBUFN VRBUFP
2
1
0
ADCDL
EOC
—
R/W
R/W
—
0
0
—
Bit 7 ~ 5FLMS2~FLMS0: ADC output data mode and clock division ratio selection
000: Normal Mode, ADC clock /30
010: Normal Mode, ADC clock /12
100: Low Latency Mode, ADC clock /30
110: Low Latency Mode, ADC clock /12
Others: Reserved
Bit 4VRBUFN: VRN Buffer Enable
0: Disable
1: Enable
Bit 3VRBUFP: VRP Buffer Enable
0: Disable
1: Enable
Bit 2ADCDL: ADC converted data latch function
0: Disable data latch
1: Enable data latch
If the ADC converted data latch function is enabled, the latest converted data value
will be latched and not be updated by any subsequent converted results until this
function is disabled. Although the converted data is latched into the data registers, the
ADC circuits remain operational, but will not generate interrupt and EOC will not
change. It is recommended that this bit should be set high before reading the converted
data in the ADRL, ADRM and ADRH registers. After the converted data has been
read out, the bit can then be cleared to low to disable the ADC data latch function and
allow further conversion values to be stored. In this way, the possibility of obtaining
undesired data during ADC conversions can be prevented.
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Bit 1EOC: End of A/D conversion flag
0: A/D conversion in progress
1: A/D conversion ended
This bit must be cleared by software.
Bit 0
Unimplemented, read as "0"
ADCS Register
Bit
7
6
5
4
3
2
1
0
Name
—
—
—
ADCK4
ADCK3
ADCK2
ADCK1
ADCK0
R/W
—
—
—
R/W
R/W
R/W
R/W
R/W
POR
—
—
—
0
0
0
0
0
Bit 7~5
Unimplemented, read as "0"
Bit 4~0ADCK4~ADCK0: Select ADC clock source (fMCLK)
00000~11110: fSYS/2 / (ADCK[4:0]+1)
11111: fSYS
Due to the ADC clock source, fMCLK, is typically designed as 4.8MHz and the MCU
might be selected to work at different system clock, therefore, the designer should
use the ADCK4~ADCK0 bits to get the fixed 4.8MHz ADC working clock source.
For example, if the system clock is 9.6MHz, the ADCK[4:0] must be 0 to get the
fMCLK=4.8MHz.
A/D Operation
The ADC provides three operational modes, which are Power down mode, Sleep mode and Reset
mode, controlled respectively by the ADOFF, ADSLP and ADRST bits in the ADCR0 register. The
following table illustrates the operating mode selection.
ADOFF
ADSLP
ADRST
1
×
×
Operating mode
Description
0
1
×
Sleep mode
PGA on, ADC off
0
0
1
Reset mode
PGA on, ADC on, SINC Reset
Power down mode PGA off, ADC off
"x" unknown
A/D operation mode selection
To enable the ADC, the first step is to disable the ADC power down and sleep mode, to make sure
the ADC is powered up. The ADRST bit in the ADCR0 register is used to start and reset the A/D converter
after power on. When the microcontroller sets this bit from low to high and then low again, an
analog to digital converted data in SINC filter will be initiated. After this setup is complete, the ADC
is ready for operation. These three bits are used to control the overall start operation of the internal
analog to digital converter.
The EOC bit in the ADCR1 register is used to indicate when the analog to digital conversion process
is complete. This bit will be automatically set high by the microcontroller after a conversion cycle
has ended. In addition, the corresponding A/D interrupt request flag will be set in the interrupt
control register, and if the interrupts are enabled, an appropriate internal interrupt signal will be
generated. This A/D internal interrupt signal will direct the program flow to the associated A/D
internal interrupt address for processing. If the A/D internal interrupt is disabled, the microcontroller
can be used to poll the EOC bit in the ADCR1 register to check whether it has been set "1" as an
alternative method of detecting the end of an A/D conversion cycle. The ADC converted data will
be updated continuously by the new converted data. If the ADC converted data latch function is
enabled, the latest converted data will be latched and the following new converted data will be
discarded until this data latch function is disabled.
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The clock source for the A/D converter should be typically fixed at a value of 4.8MHz, which
originates from the system clock fSYS, and can be chosen to be either fSYS or a subdivided version
of fSYS. The division ratio value is determined by the ADCK4~ADCK0 bits in the ADCS register to
obtain a 4.8MHz clock source for the ADC.
The differential reference voltage supply to the A/D Converter can be supplied from either the
internal power supply pins, VCM and AVSS, or from an external reference source supplied on pins,
VREFP and VREFN. The desired selection is made using the VREFS bit in the ADCR0 register.
Summary of A/D Conversion Steps
The following summarises the individual steps that should be executed in order to implement an A/D
conversion process.
• Step 1
Enable power LDO, VCM for PGA and ADC.
• Step 2
Select PGA, ADC and VREF gain by PGAC0 register.
• Step 3
Select PGA setting for input pins connection and VCM option by PGAC1 register.
• Step 4
Select the required A/D conversion clock 4.8MHz by correctly programming bits
ADCK4~ADCK0 in the ADCS register.
• Step 5
Select output data rate.
• Step 6
Select which channel is to be connected to the internal PGA by correctly programming the
CHSP2~CHSP0 and CHSN2~CHSN0 bits which are also contained in the PGACS register.
• Step 7
Release power down mode and sleep mode by ADOFF and ADSLP bits in ADCR0 register.
• Step 8
Reset the A/D by setting the ADRST to high in the ADCR0 register and clearing this bit to zero
to release reset status.
• Step 9
If the interrupts are to be used, the interrupt control registers must be correctly configured to
ensure the A/D converter interrupt function is active. The master interrupt control bit, EMI, and
the A/D converter interrupt bit, ADE, must both be set high to do this.
• Step 10
To check when the analog to digital conversion process is complete, the EOC bit in the ADCR1
register can be polled. The conversion process is complete when this bit goes low. When this
occurs the A/D data registers ADRL, ADRM and ADRH can be read to obtain the conversion
value. As an alternative method, if the interrupts are enabled and the stack is not full, the program
can wait for an A/D interrupt to occur.
Note: When checking for the end of the conversion process, if the method of polling the EOC bit in
the ADCR1 register is used, the interrupt enable step above can be omitted.
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Programming Considerations
During microcontroller operations where the A/D converter is not being used, the A/D internal
circuitry can be switched off to reduce power consumption, by setting bit ADOFF high in the
ADCR0 register. When this happens, the internal A/D converter circuits will not consume power
irrespective of what analog voltage is applied to their input lines.
A/D Transfer Function
This device contains a 20-bit ΔΣA/D converter, its full-scale converted digitised value is from
524287 to -524288 in decimal value. The converted data format is formed by a two’s complement
binary value. The MSB of the converted data is the signed bit. Since the full-scale analog input
value is equal to the VCM or ΔVREF voltage, selected by the VREFS bit in ADCR0 register, this gives
a single bit analog input value of VCM or ΔVREF divided by 524288.
1 LSB= (VCM or ΔVREF) /524288
The A/D Converter input voltage value can be calculated using the following equation:
ΔSI_I = (PGAGN × ADGN × ΔDI±) + (DCSET × ΔVR_I)
ΔVR_I = VREGN × ΔVR±
ADC_Conversion_Data = (ΔSI_I ÷ ΔVR_I) × K
Where K is equal to 2
Note: The PGAGN, ADGN, VREGN values are decided by PGS, AGS, VGS control bits.
19
ΔSI_I: Differential Input Signal after process
PGAGN: Programmable Gain Amplifier gain
ADGN: ADC gain
ΔDI ±: Differential Input signal
DCSET: Offset voltage
ΔVR ±: Differential Reference voltage
ΔVR_I: Differential Reference input voltage after process
VREGN: Reference voltage gain
Due to the digital system design of the ΔΣADC, the maximum number of the ADC converted value
is 524287 and the minimum value is -524288, therefore, we can have the middle number 0. The
ADC_Conversion_Data equation illustrates this range of converted data variation.
A/D conversion data
(2’s compliment, Hexadecimal)
Decimal Value
0x7FFFF
524287
0x80000
-524288
The above ADC conversion data table illustrates the range of ADC conversion data.
The following diagram shows the relationship between the DC input value and the ADC converted
data which is presented by the Two’s Complement.
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20 Digital output
Two's complement
0111 1111 1111 1111 1111
DC input value
0
PGAGN× ADGN
AIP − AIN
DCSET
×
+
VREGN
VREFP − VREFN VREGN
1000 0000 0000 0000 0000
A/D Converted Data
The ADC converted data is related to the input voltage and the PGA selections. The format of the
ADC output is a two’s complement binary code. The length of this output code is 20 bits and the
MSB is a signed bit. When the MSB is "0", which represents the input is "positive", on the other
hand, as the MSB is "1", it represents the input is "negative". The maximum value is 524287 and
the minimum value is -524288. If the input signal is over the maximum value, the converted data is
limited by the 524287, and if the input signal is less than the minimum value, the converted data is
limited by -524288.
A/D Converted Data to Voltage
The designer can recover the converted data by the following equations:
If MSB=0 (Positive Converted data):
Input Voltage = (Converted data-0) × (LSB/ PGA)
If the MSB=1(Negative Converted data):
Input voltage= (Two’s complement of converted data-0) × (LSB/PGA)
Note: Two’s complement=One’s complement +1
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A/D Programming Example
Example: Using an EOC polling method to detect the end of conversion
#includeht45f77.inc
data.section ‘data’
adc_result_data_l db ?
adc_result_data_m db ?
adc_result_data_h db ?
code.section ‘code’
start:
clr
ADE; disable ADC interrupt
mova, 0C3H ; Power control for PGA, ADC
movPWRC, a ; PWRC=11000011, LDO enable, VCM enable, LDO Bypass disable,
; LDO output voltage: 3.3V
mova, 000H
movPGAC0, a ; PGA gain=1, ADC gain=1, VREF gain=1
mova, 080H
movPGAC1, a ; VCM=1.25V, INIS, DCSET2~0 in default value
setVRBUFP ; enable buffer for VREF+
setVRBUFN ; enable buffer for VREF
setVREFS ; for using external reference
clrADOR2 ; for 10Hz output data rate, ADOR[2:0]=001, FLMS[2:0]=000
clrADOR1
setADOR0
clrFLMS2
clrFLMS1
clrFLMS0
clrADOFF ; ADC exit power down mode.
setADRST ; ADC in reset mode
clrADRST ; ADC in convertsion (continuos mode)
clrEOC ; Clear "EOC" flag
loop:
snzEOC ; Polling "EOC" flag
jmploop ; Wait for read data
clradc_result_data_h
clradc_result_data_m
clradc_result_data_l
mova, ADRL
movadc_result_data_l, a; Get Low byte ADC value
mova, ADRM
movadc_result_data_m, a; Get Middle byte ADC value
mova, ADRH
movadc_result_data_h, a; Get High byte ADC value
get_adc_value_ok:
clrEOC ; Clearing read flag
jmp
loop; for next data read
end
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Temperature Sensor
This device provides an internal temperature sensor to compensate the device performance.
By selecting the PGA input channels to VTSO+ and VTSO-, the ADC can get the temperature
information and the designer can do some compensation to the A/D converted data. The following
block diagram illustrates the functional operation for the temperature sensor.
AVDD
I
VTSO+
VTSO-
PGA
ADC
AVSS
Serial Interface Module – SIM
This device contains 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 memory,
etc. 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 pins are selected using pull-high control
registers when the SIM function is enabled and the corresponding pins are used as SIM input pins.
SPI Interface
The SPI interface is often used to communicate with external peripheral devices such as sensors,
Flash 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 is 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 normal I/O pins and with the I2C function pins, the SPI interface must first be enabled
by setting the correct bits in the SIMC0 and SIMC2 registers. The SPI can be disabled or enabled
using the SIMEN bit in the SIMC0 register. Communication between devices connected to the SPI
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 SCS
pin only one slave device can be utilized. The SCS pin is controlled by software, set CSEN bit to "1"
to enable SCS pin function, set CSEN bit to "0" the SCS pin will be floating state.
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SPI Master/Slave Connection

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The SPI 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
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 three internal registers which control the overall operation of the SPI interface. These are
the SIMD data register and two registers SIMC0 and SIMC2. Note that the SIMC1 register is only
used by the I2C interface.
Bit
Register
Name
7
6
5
SIMC0
SIM2
SIM1
SIM0
—
SIMD
D7
D6
D5
D4
D3
D2
SIMC2
D7
D6
CKPOLB
CKEG
MLS
CSEN
4
3
2
SIMDBC1 SIMDBC0
1
0
SIMEN
SIMICF
D1
D0
WCOL
TRF
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.
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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 two control registers for the SPI interface, SIMC0 and SIMC2. 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
Bit
7
6
5
4
3
2
Name
SIM2
SIM1
SIM0
—
R/W
R/W
R/W
R/W
—
R/W
R/W
POR
1
1
1
—
0
0
SIMDBC1 SIMDBC0
1
0
SIMEN
SIMICF
R/W
R/W
0
0
Bit 7~5SIM2~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 fSUB
100: SPI master mode; SPI clock is TM0 CCRP match frequency/2
101: SPI slave mode
110: I2C slave mode
111: Unused mode
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 fSUB or TM0. If the SPI Slave Mode is
selected then the clock will be supplied by an external Master device.
Bit 4
Unimplemented, read as "0"
Bit 3~2SIMDBC1~SIMDBC0: I2C Debounce Time Selection
00: No debounce
01: 2 system clock debounce
1x: 4 system clock debounce
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Bit 1SIMEN: SIM Control
0: Disable
1: Enable
The bit is the overall on/off control for the SIM interface. When the SIMEN bit is
cleared to zero to disable the SIM interface, the SDI, SDO, SCK and SCS, or SDA
and SCL lines will be in a floating condition and the SIM operating current will be
reduced to a minimum value. When the bit is high the SIM interface is enabled. The
SIM configuration option must have first enabled the SIM interface for this bit to be
effective. 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 0SIMICF: SIM Incompleted Flag
0: SIM incompleted is not occurred
1: SIM incompleted is occurred
The SIMICF bit is determined by SCS pin. When SCS pin is set high, it will clear the
SPI counter. Meanwhile, the interrupt is occurred and the incompleted flag, SIMICF, is
set high.
SIMC2 Register
Bit
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 7~6D7~D6: Undefined bit
This bit can be read or written by user software program.
Bit 5CKPOLB: Determines the base condition of the clock line
0: The SCK line will be high when the clock is inactive
1: The SCK line will be low when the clock is inactive
The CKPOLB bit determines the base condition of the clock line, if the bit is high,
then the SCK line will be low when the clock is inactive. When the CKPOLB bit is
low, then the SCK line will be high when the clock is inactive.
Bit 4CKEG: Determines SPI SCK active clock edge type
CKPOLB=0
0: SCK is high base level and data capture at SCK rising edge
1: SCK is high base level and data capture at SCK falling edge
CKPOLB=1
0: SCK is low base level and data capture at SCK falling edge
1: SCK is low base level and data capture at SCK rising edge
The CKEG and CKPOLB bits are used to setup the way that the clock signal outputs
and inputs data on the SPI bus. These two bits must be configured before data transfer
is executed otherwise an erroneous clock edge may be generated. The CKPOLB bit
determines the base condition of the clock line, if the bit is high, then the SCK line
will be low when the clock is inactive. When the CKPOLB bit is low, then the SCK
line will be high when the clock is inactive. The CKEG bit determines active clock
edge type which depends upon the condition of CKPOLB bit.
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Bit 3MLS: SPI Data shift order
0: LSB
1: MSB
This is the data shift select bit and is used to select how the data is transferred, either
MSB or LSB first. Setting the bit high will select MSB first and low for LSB first.
Bit 2CSEN: SPI SCS pin Control
0: Disable
1: Enable
The CSEN bit is used as an enable/disable for the SCS pin. If this bit is low, then the
SCS pin will be disabled and placed into a floating condition. If the bit is high the SCS
pin will be enabled and used as a select pin.
Note that using the CSEN bit can be disabled or enabled via configuration option.
Bit 1WCOL: SPI Write Collision flag
0: No collision
1: Collision
The WCOL flag is used to detect if a data collision has occurred. If this bit is high it
means that data has been attempted to be written to the SIMD register during a data
transfer operation. This writing operation will be ignored if data is being transferred.
The bit can be cleared by the application program. Note that using the WCOL bit can
be disabled or enabled via configuration option.
Bit 0TRF: SPI Transmit/Receive Complete flag
0: Data is being transferred
1: SPI data transmission is completed
The TRF bit is the Transmit/Receive Complete flag and is set high automatically when
an SPI data transmission is completed, but must cleared to zero by the application
program. It can be used to generate an interrupt.
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.
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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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I2C Interface
The I2C interface is used to communicate with external peripheral devices such as sensors etc.
Originally developed by Philips, it is a two line low speed serial interface for synchronous serial
data transfer. The advantage of only two lines for communication, relatively simple communication
protocol and the ability to accommodate multiple devices on the same bus has made it an extremely
popular interface type for many applications.
I2C Master/Slave Bus Connection
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I2C Interface Operation
The I2C serial interface is a two line interface, a serial data line, SDA, and serial clock line, SCL. As
many devices may be connected together on the same bus, their outputs are both open drain types.
For this reason it is necessary that external pull-high resistors are connected to these outputs. Note
that no chip select line exists, as each device on the I2C bus is identified by a unique address which
will be transmitted and received on the I2C bus.
When two devices communicate with each other on the bidirectional I2C bus, one is known as the
master device and one as the slave device. Both master and slave can transmit and receive data,
however, it is the master device that has overall control of the bus. For this device, which only
operates in slave mode, there are two methods of transferring data on the I2C bus, the slave transmit
mode and the slave receive mode. The pull-up control function pin-shared with SCL/SDA pin is still
applicable even if I2C device is activated and the related internal pull-up register could be controlled
by its corresponding pull-up control register.
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„ I C Block Diagram
2
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I2C Registers
There are three control registers associated with the I2C bus, SIMC0, SIMC1 and SIMTOC, 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 SIMTOC
register is used for I2C time-out control.
Bit
Register
Name
7
SIMC0
SIMC1
6
5
4
SIM2
SIM1
SIM0
—
HCF
HAAS
HBB
HTX
3
2
SIMDBC1 SIMDBC0
TXAK
SRW
1
0
SIMEN
SIMICF
RNIC
RXAK
SIMD
D7
D6
D5
D4
D3
D2
D1
D0
SIMA
IICA6
IICA5
IICA4
IICA3
IICA2
IICA1
IICA0
D0
SIMTOC SIMTOEN SIMTOF SIMTOS5 SIMTOS4 SIMTOS3 SIMTOS2 SIMTOS1 SIMTOS0
I2C Registers List
SIMC0 Register
Bit
7
6
5
4
Name
SIM2
SIM1
SIM0
—
3
R/W
R/W
R/W
R/W
—
R/W
POR
1
1
1
—
0
2
1
0
SIMEN
SIMICF
R/W
R/W
R/W
0
0
0
SIMDBC1 SIMDBC0
Bit 7~5SIM2~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 fSUB
100: SPI master mode; SPI clock is TM0 CCRP match frequency/2
101: SPI slave mode
110: I2C slave mode
111: Unused mode
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 fSUB or TM0. If the SPI Slave Mode is
selected then the clock will be supplied by an external Master device.
Bit 4
Unimplemented, read as "0"
Bit 3~2SIMDBC1~SIMDBC0: I2C Debounce Time Selection
00: No debounce
01: 2 system clock debounce
1x: 4 system clock debounce
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Bit 1SIMEN: SIM Control
0: Disable
1: Enable
The bit is the overall on/off control for the SIM interface. When the SIMEN bit is
cleared to zero to disable the SIM interface, the SDI, SDO, SCK and SCS, or SDA
and SCL lines will be in a floating condition and the SIM operating current will be
reduced to a minimum value. When the bit is high the SIM interface is enabled. The
SIM configuration option must have first enabled the SIM interface for this bit to be
effective. 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 0SIMICF: SIM Incompleted Flag
SIMICF is of no used in I2C mode of SIM, please ignore this flag when operate in I2C
mode.
SIMC1 Register
Bit
7
6
5
4
3
2
1
0
Name
HCF
HAAS
HBB
HTX
TXAK
SRW
RNIC
RXAK
R/W
R
R
R
R/W
R/W
R
R/W
R
POR
1
0
0
0
0
0
0
1
Bit 7HCF: I C Bus data transfer completion flag
0: Data is being transferred
1: Completion of an 8-bit data transfer
The HCF flag is the data transfer flag. This flag will be zero when data is being
transferred. Upon completion of an 8-bit data transfer the flag will go high and an
interrupt will be generated.
2
Bit 6HAAS: I2C Bus address match flag
0: Not address match
1: Address match
The 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 5HBB: I2C Bus busy flag
0: I2C Bus is not busy
1: I2C Bus is busy
The HBB flag is the I2C busy flag. This flag will be "1" when the I2C bus is busy which
will occur when a START signal is detected. The flag will be cleared to zero when the
bus is free which will occur when a STOP signal is detected.
Bit 4HTX: Select I2C slave device is transmitter or receivera
0: Slave device is the receiver
1: Slave device is the transmitter
Bit 3TXAK: I2C Bus transmit acknowledge flag
0: Slave send acknowledge flag
1: Slave do not send acknowledge flag
The TXAK bit is the transmit acknowledge flag. After the slave device receipt of 8-bits
of data, this bit will be transmitted to the bus on the 9th clock from the slave device.
The slave device must always set TXAK bit to "0" before further data is received.
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Bit 2SRW: I2C Slave Read/Write flag
0: Slave device should be in receive mode
1: Slave device should be in transmit mode
The SRW flag is the I 2C Slave Read/Write flag. This flag determines whether
the master device wishes to transmit or receive data from the I2C bus. When the
transmitted address and slave address is match, that is when the HAAS flag is set high,
the slave device will check the SRW flag to determine whether it should be in transmit
mode or receive mode. If the SRW flag is high, the master is requesting to read data
from the bus, so the slave device should be in transmit mode. When the SRW flag
is zero, the master will write data to the bus, therefore the slave device should be in
receive mode to read this data.
Bit 1RNIC: I2C Running Not using Internal Clock.
0: I2C running using internal clock.
1: I2C running NOT using internal clock.
The I2C module can run without using internal clock, and generate an interrupt if the
SIM interrupt is enabled, which can be used in sleep mode, idle (slow) mode and
normal (slow) mode.
Note: if RNIC=1 and MCU is in halt, slave-receiver can work well but
slave-transmitter doesn’t work since it needs system clock.
Bit 0RXAK: I2C Bus Receive acknowledge flag
0: Slave receive acknowledge flag
1: Slave do not receive acknowledge flag
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 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
device can read it from the SIMD register. Any transmission or reception of data from the I2C 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
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 7~1IICA6~IICA0: I2C slave address
IICA6~ IICA0 is the I2C slave address bit 6 ~ bit 0.
The SIMA register is also used by the SPI interface but has the name SIMC2. The
SIMA register is the location where the 7-bit slave address of the slave device is
stored. Bits 7~ 1 of the SIMA register define the device slave address. Bit 0 is not
defined.
When a master device, which is connected to the I2C bus, sends out an address, which
matches the slave address in the SIMA register, the slave device will be selected. Note
that the SIMA register is the same register address as SIMC2 which is used by the SPI
interface.
Bit 0
Rev. 1.10
Undefined bit
This bit can be read or written by user software program.
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SIMTOC Register
Bit
7
Name
SIMTOEN
6
5
4
3
2
1
0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
0
0
0
0
0
0
0
SIMTOF SIMTOS5 SIMTOS4 SIMTOS3 SIMTOS2 SIMTOS1 SIMTOS0
Bit 7SIMTOEN: I2C interface Time-out control
0: Disable
1: Enable
Bit 6SIMTOF: I2C interface Time-out flag
0: No occurred
1: Occurred
The SIMTOF flag is set by the time-out circuitry when the time-out event occurs and
cleared by software program.
Bit 5~0SIMTOS5~SIMTOS0: I2C interface Time-out period selection
The I2C Time-Out clock source is fSUB/32.
The I2C Time-Out time is ([SIMTOS5:SIMTOS0] + 1) × (32/fSUB)
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 bits to "110" and the SIMEN bits to "1" in the SIMC0 register 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 SIE and SIM Muti-Function interrupt enable bit of the interrupt control register to enable
the SIM interrupt and Multi-function interrupt.
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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 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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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 high. 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 cleared to zero.
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.
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€

€

­
         ­ I C Communication Timing Diagram
2
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
In order to reduce the I2C lockup problem due to reception of erroneous clock sources, a time-out
function is provided. If the clock source connected to the I2C bus is not received for a while, then the
I2C circuitry and the SIMC1 register will be reset, the SIMTOF bit in the SIMTOC register will be
set high after a certain time-out period. The Time Out function eable/disable and the time-out period
are managed by the SIMTOC register.
I2C Time Out Operation
The time-out counter starts to count on an I2C bus "START" & "address match" condition, and is
cleared by an SCL falling edge. Before the next SCL falling edge arrives, if the time elapsed is
greater than the time-out period specified by the SIMTOC register, then a time-out condition will
occur. The time-out function will stop when an I2C "STOP" condition occurs. There are 64 time-out
period selections which can be selected using the SIMTOS0~SIMTOS5 bits in the SIMTOC register.
S C L
S ta rt
S R W
S la v e A d d r e s s
0
1
S D A
1
1
0
1
0
1
A C K
0
I2 C t i m e - o u t
c o u n te r s ta rt
S to p
S C L
1
0
0
1
0
1
0
0
S D A
I2 C t im e - o u t c o u n t e r r e s e t
o n S C L n e g a tiv e tr a n s itio n
I2C Time-out Diagram
When an I2C time-out counter overflow occurs, the counter will stop and the SIMTOEN bit will
be cleared to zero and the SIMTOF bit will be set high to indicate that a time-out condition has
occurred. The time-out condition will also generate an interrupt which uses the I2C interrrupt vector.
When an I2C time-out occurs, the I2C internal circuitry will be reset and the registers will be reset
into the following condition:
Register
After I2C Tiome-out
SIMD, SIMA, SIMC0
No change
SIMC1
Reset to POR condition
I C Registers after Time-out
2
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UART Module Serial Interface with IR Carrier
UART Module Features
• Full-duplex, Universal Asynchronous Receiver and Transmitter (UART) communication
• 8 or 9 bits character length
• Even, odd or no parity options
• One or two stop bits
• Baud rate generator with 8-bit prescaler
• Parity, framing, noise and overrun error detection
• Support for interrupt on address detect (last character bit=1)
• Transmitter and receiver enabled independently
• 2-byte Deep FIFO Receive Data Buffer
• Transmit and Receive Multiple Interrupt Generation Sources:
♦♦
Transmitter Empty
♦♦
Transmitter Idle
♦♦
Receiver Full
♦♦
Receiver Overrun
♦♦
Address Mode Detect
UART Module Overview
The embedded UART Module is full-duplex asynchronous serial communications UART interface
that enables communication with external devices that contain a serial interface. The UART function
has many features and can transmit and receive data serially by transferring a frame of data with
eight or nine data bits per transmission as well as being able to detect errors when the data is
overwritten or incorrectly framed. The UART function possesses its own internal interrupt which
can be used to indicate when a reception occurs or when a transmission terminates.
UART External Pin Interfacing
To communicate with an external serial interface, the internal UART has two external pins known
as TX and RX. The TX pin is the UART transmitter pin, which can be used as a general purpose I/
O or other pin-shared functional pin if the pin is not configured as a UART transmitter, which occurs
when the TXEN bit in the UCR2 control register is equal to zero. Similarly, the RX pin is the UART
receiver pin, which can also be used as a general purpose I/O or other pin-shared functional pin, if
the pin is not configured as a receiver, which occurs if the RXEN bit in the UCR2 register is equal to
zero. Along with the UARTEN bit, the TXEN and RXEN bits, if set, will automatically setup these
I/O or other pin-shared functional pins to their respective TX output and RX input conditions and
disable any pull-high resistor option which may exist on the RX pin.
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UART Data Transfer Scheme
The block diagram shows the overall data transfer structure arrangement for the UART. The actual
data to be transmitted from the MCU is first transferred to the TXR register by the application
program. The data will then be transferred to the Transmit Shift Register from where it will be
shifted out, LSB first, onto the TX pin at a rate controlled by the Baud Rate Generator. Only the
TXR register is mapped onto the MCU Data Memory, the Transmit Shift Register is not mapped and
is therefore inaccessible to the application program.
Data to be received by the UART is accepted on the external RX pin, from where it is shifted in,
LSB first, to the Receiver Shift Register at a rate controlled by the Baud Rate Generator. When
the shift register is full, the data will then be transferred from the shift register to the internal RXR
register, where it is buffered and can be manipulated by the application program. Only the RXR
register is mapped onto the MCU Data Memory, the Receiver Shift Register is not mapped and is
therefore inaccessible to the application program.
It should be noted that the actual register for data transmission and reception, although referred to
in the text, and in application programs, as separate TXR and RXR registers, only exists as a single
shared register in the Data Memory. This shared register known as the TXRRXR register is used for
both data transmission and data reception.
T�ansmitte� Shift Registe� (TSR)
MSB
…………………………
Receive� Shift Registe� (RSR)
LSB
TX Pin
TX Registe� (TXR)
RX Pin
MSB
LSB
RX Registe� (RXR)
Ba�d Rate
Gene�ato�
fSYS
…………………………
B�ffe�
Data to be t�ansmitted
Data �eceived
MCU Data B�s
UART Data Transfer Scheme
UART Status and Control Registers
There are five control registers associated with the UART function. The USR, UCR1 and UCR2
registers control the overall function of the UART, while the BRG register controls the Baud
rate. The actual data to be transmitted and received on the serial interface is managed through the
TXRRXR data register.
Register
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
USR
PERR
NF
FERR
OERR
RIDLE
RXIF
TIDLE
TXIF
UCR1
UARTEN
BNO
PREN
PRT
STOPS
TXBRK
RX8
TX8
UCR2
TXEN
RXEN
BRGH
ADDEN
WAKE
RIE
TIIE
TEIE
TXRXD6
TXRXD5
TXRXD4
TXRXD3
TXRXD2
TXRXD1
TXRXD0
BRGD6
BRGD5
BRGD4
BRGD3
BRGD2
BRGD1
BRGD0
TXRRXR TXRXD7
BRG
BRGD7
UART Register Summary
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USR Register
The USR register is the status register for the UART, which can be read by the program to determine
the present status of the UART. All flags within the USR register are read only. Further explanation
on each of the flags is given below:
Bit
7
6
5
4
3
2
1
0
Name
PERR
NF
FERR
OERR
RIDLE
RXIF
TIDLE
TXIF
R/W
R
R
R
R
R
R
R
R
POR
0
0
0
0
1
0
1
1
Bit 7PERR: Parity error flag
0: No parity error is detected
1: Parity error is detected
The PERR flag is the parity error flag. When this read only flag is "0", it indicates a
parity error has not been detected. When the flag is "1", it indicates that the parity of
the received word is incorrect. This error flag is applicable only if Parity mode (odd or
even) is selected. The flag can also be cleared by a software sequence which involves
a read to the status register USR followed by an access to the RXR data register.
Bit 6NF: Noise flag
0: No noise is detected
1: Noise is detected
The NF flag is the noise flag. When this read only flag is "0", it indicates no noise
condition. When the flag is "1", it indicates that the UART has detected noise on the
receiver input. The NF flag is set during the same cycle as the RXIF flag but will not
be set in the case of as overrun. The NF flag can be cleared by a software sequence
which will involve a read to the status register USR followed by an access to the RXR
data register.
Bit 5FERR: Framing error flag
0: No framing error is detected
1: Framing error is detected
The FERR flag is the framing error flag. When this read only flag is "0", it indicates
that there is no framing error. When the flag is "1", it indicates that a framing error
has been detected for the current character. The flag can also be cleared by a software
sequence which will involve a read to the status register USR followed by an access to
the RXR data register.
Bit 4OERR: Overrun error flag
0: No overrun error is detected
1: Overrun error is detected
The OERR flag is the overrun error flag which indicates when the receiver buffer has
overflowed. When this read only flag is "0", it indicates that there is no overrun error.
When the flag is "1", it indicates that an overrun error occurs which will inhibit further
transfers to the RXR receive data register. The flag is cleared by a software sequence,
which is a read to the status register USR followed by an access to the RXR data
register.
Bit 3RIDLE: Receiver status
0: Data reception is in progress (data being received)
1: No data reception is in progress (receiver is idle)
The RIDLE flag is the receiver status flag. When this read only flag is "0", it indicates
that the receiver is between the initial detection of the start bit and the completion of
the stop bit. When the flag is "1", it indicates that the receiver is idle. Between the
completion of the stop bit and the detection of the next start bit, the RIDLE bit is "1"
indicating that the UART receiver is idle and the RX pin stays in logic high condition.
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Bit 2RXIF: Receive RXR data register status
0: RXR data register is empty
1: RXR data register has available data
The RXIF flag is the receive data register status flag. When this read only flag is "0",
it indicates that the RXR read data register is empty. When the flag is "1", it indicates
that the RXR read data register contains new data. When the contents of the shift
register are transferred to the RXR register, an interrupt is generated if RIE=1 in the
UCR2 register. If one or more errors are detected in the received word, the appropriate
receive-related flags NF, FERR, and/or PERR are set within the same clock cycle. The
RXIF flag is cleared when the USR register is read with RXIF set, followed by a read
from the RXR register, and if the RXR register has no data available.
Bit 1TIDLE: Transmission idle
0: Data transmission is in progress (data being transmitted)
1: No data transmission is in progress (transmitter is idle)
The TIDLE flag is known as the transmission complete flag. When this read only
flag is "0", it indicates that a transmission is in progress. This flag will be set high
when the TXIF flag is "1" and when there is no transmit data or break character being
transmitted. When TIDLE is equal to "1", the TX pin becomes idle with the pin state
in logic high condition. The TIDLE flag is cleared by reading the USR register with
TIDLE set and then writing to the TXR register. The flag is not generated when a data
character or a break is queued and ready to be sent.
Bit 0TXIF: Transmit TXR data register status
0: Character is not transferred to the transmit shift register
1: Character has transferred to the transmit shift register (TXR data register is
empty)
The TXIF flag is the transmit data register empty flag. When this read only flag is "0",
it indicates that the character is not transferred to the transmitter shift register. When
the flag is "1", it indicates that the transmitter shift register has received a character
from the TXR data register. The TXIF flag is cleared by reading the UART status
register (USR) with TXIF set and then writing to the TXR data register. Note that
when the TXEN bit is set, the TXIF flag bit will also be set since the transmit data
register is not yet full.
UCR1 Register
The UCR1 register together with the UCR2 register are the two UART control registers that are used
to set the various options for the UART function, such as overall on/off control, parity control, data
transfer bit length etc. Further explanation on each of the bits is given below:
Bit
7
6
5
4
3
2
1
0
Name
UARTEN
BNO
PREN
PRT
STOPS
TXBRK
RX8
TX8
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R
W
POR
0
0
0
0
0
0
x
0
"x" unknown
Bit 7UARTEN: UART function enable control
0: Disable UART. TX and RX pins are used as I/O or other pin-shared functional
pins
1: Enable UART. TX and RX pins function as UART pins
The UARTEN bit is the UART enable bit. When this bit is equal to "0", the UART will
be disabled and the RX pin as well as the TX pin will be as General Purpose I/O or other
pin-shared functional pins. When the bit is equal to "1", the UART will be enabled and
the TX and RX pins will function as defined by the TXEN and RXEN enable control
bits.
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When the UART is disabled, it will empty the buffer so any character remaining in
the buffer will be discarded. In addition, the value of the baud rate counter will be
reset. If the UART is disabled, all error and status flags will be reset. Also the TXEN,
RXEN, TXBRK, RXIF, OERR, FERR, PERR and NF bits will be cleared, while the
TIDLE, TXIF and RIDLE bits will be set. Other control bits in UCR1, UCR2 and
BRG registers will remain unaffected. If the UART is active and the UARTEN bit is
cleared, all pending transmissions and receptions will be terminated and the module
will be reset as defined above. When the UART is re-enabled, it will restart in the
same configuration.
Bit 6BNO: Number of data transfer bits selection
0: 8-bit data transfer
1: 9-bit data transfer
This bit is used to select the data length format, which can have a choice of either
8-bit or 9-bit format. When this bit is equal to "1", a 9-bit data length format will be
selected. If the bit is equal to "0", then an 8-bit data length format will be selected. If
9-bit data length format is selected, then bits RX8 and TX8 will be used to store the
9th bit of the received and transmitted data respectively.
Bit 5PREN: Parity function enable control
0: Parity function is disabled
1: Parity function is enabled
This is the parity enable bit. When this bit is equal to "1", the parity function will be
enabled. If the bit is equal to "0", then the parity function will be disabled. Replace the
most significant bit position with a parity bit.
Bit 4PRT: Parity type selection bit
0: Even parity for parity generator
1: Odd parity for parity generator
This bit is the parity type selection bit. When this bit is equal to "1", odd parity type
will be selected. If the bit is equal to "0", then even parity type will be selected.
Bit 3STOPS: Number of Stop bits selection
0: One stop bit format is used
1: Two stop bits format is used
This bit determines if one or two stop bits are to be used. When this bit is equal to "1",
two stop bits are used. If this bit is equal to "0", then only one stop bit is used.
Bit 2TXBRK: Transmit break character
0: No break character is transmitted
1: Break characters transmit
The TXBRK bit is the Transmit Break Character bit. When this bit is "0", there are
no break characters and the TX pin operates normally. When the bit is "1", there are
transmit break characters and the transmitter will send logic zeros. When this bit is
equal to "1", after the buffered data has been transmitted, the transmitter output is held
low for a minimum of a 13-bit length and until the TXBRK bit is reset.
Bit 1RX8: Receive data bit 8 for 9-bit data transfer format (read only)
This bit is only used if 9-bit data transfers are used, in which case this bit location will
store the 9th bit of the received data known as RX8. The BNO bit is used to determine
whether data transfers are in 8-bit or 9-bit format.
Bit 0TX8: Transmit data bit 8 for 9-bit data transfer format (write only)
This bit is only used if 9-bit data transfers are used, in which case this bit location
will store the 9th bit of the transmitted data known as TX8. The BNO bit is used to
determine whether data transfers are in 8-bit or 9-bit format.
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UCR2 Register
The UCR2 register is the second of the two UART control registers and serves several purposes. One
of its main functions is to control the basic enable/disable operation of the UART Transmitter and
Receiver as well as enabling the various UART interrupt sources. The register also serves to control
the baud rate speed, receiver wake-up enable and the address detect enable. Further explanation on
each of the bits is given below:
Bit
7
6
5
4
3
2
1
0
Name
TXEN
RXEN
BRGH
ADDEN
WAKE
RIE
TIIE
TEIE
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 7TXEN: UART Transmitter enabled control
0: UART transmitter is disabled
1: UART transmitter is enabled
The bit named TXEN is the Transmitter Enable Bit. When this bit is equal to "0", the
transmitter will be disabled with any pending data transmissions being aborted. In
addition the buffers will be reset. In this situation the TX pin will be used as an I/O or
other pin-shared functional pin.
If the TXEN bit is equal to "1" and the UARTEN bit is also equal to "1", the
transmitter will be enabled and the TX pin will be controlled by the UART. Clearing
the TXEN bit during a transmission will cause the data transmission to be aborted and
will reset the transmitter. If this situation occurs, the TX pin will be used as an I/O or
other pin-shared functional pin.
Bit 6RXEN: UART Receiver enabled control
0: UART receiver is disabled
1: UART receiver is enabled
The bit named RXEN is the Receiver Enable Bit. When this bit is equal to "0", the
receiver will be disabled with any pending data receptions being aborted. In addition
the receive buffers will be reset. In this situation the RX pin will be used as an I/O or
other pin-shared functional pin. If the RXEN bit is equal to "1" and the UARTEN bit
is also equal to "1", the receiver will be enabled and the RX pin will be controlled by
the UART. Clearing the RXEN bit during a reception will cause the data reception to
be aborted and will reset the receiver. If this situation occurs, the RX pin will be used
as an I/O or other pin-shared functional pin.
Bit 5BRGH: Baud Rate speed selection
0: Low speed baud rate
1: High speed baud rate
The bit named BRGH selects the high or low speed mode of the Baud Rate Generator.
This bit, together with the value placed in the baud rate register BRG, controls the
Baud Rate of the UART. If this bit is equal to "1", the high speed mode is selected. If
the bit is equal to "0", the low speed mode is selected.
Bit 4
Rev. 1.10
ADDEN: Address detect function enable control
0: Address detect function is disabled
1: Address detect function is enabled
The bit named ADDEN is the address detect function enable control bit. When this
bit is equal to "1", the address detect function is enabled. When it occurs, if the 8th
bit, which corresponds to RX7 if BNO=0 or the 9th bit, which corresponds to RX8 if
BNO=1, has a value of "1", then the received word will be identified as an address,
rather than data. If the corresponding interrupt is enabled, an interrupt request will be
generated each time the received word has the address bit set, which is the 8th or 9th
bit depending on the value of BNO. If the address bit known as the 8th or 9th bit of the
received word is "0" with the address detect function being enabled, an interrupt will
not be generated and the received data will be discarded.
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Bit 3WAKE: RX pin falling edge wake-up function enable control
0: RX pin wake-up function is disabled
1: RX pin wake-up function is enabled
This bit enables or disables the receiver wake-up function. If this bit is equal to "1"
and the MCU is in IDLE0 or SLEEP mode, a falling edge on the RX input pin will
wake-up the device. Please reference the UART RX pin wake-up functions in different
operating mode for the detail. If this bit is equal to "0" and the MCU is in IDLE or
SLEEP mode, any edge transitions on the RX pin will not wake-up the device.
Bit 2RIE: Receiver interrupt enable control
0: Receiver related interrupt is disabled
1: Receiver related interrupt is enabled
This bit enables or disables the receiver interrupt. If this bit is equal to "1" and when
the receiver overrun flag OERR or receive data available flag RXIF is set, the UART
interrupt request flag will be set. If this bit is equal to "0", the UART interrupt request
flag will not be influenced by the condition of the OERR or RXIF flags.
Bit 1TIIE: Transmitter Idle interrupt enable control
0: Transmitter idle interrupt is disabled
1: Transmitter idle interrupt is enabled
This bit enables or disables the transmitter idle interrupt. If this bit is equal to "1" and
when the transmitter idle flag TIDLE is set, due to a transmitter idle condition, the
UART interrupt request flag will be set. If this bit is equal to "0", the UART interrupt
request flag will not be influenced by the condition of the TIDLE flag.
Bit 0TEIE: Transmitter Empty interrupt enable control
0: Transmitter empty interrupt is disabled
1: Transmitter empty interrupt is enabled
This bit enables or disables the transmitter empty interrupt. If this bit is equal to "1"
and when the transmitter empty flag TXIF is set, due to a transmitter empty condition,
the UART interrupt request flag will be set. If this bit is equal to "0", the UART
interrupt request flag will not be influenced by the condition of the TXIF flag.
TXRRXR Register
Bit
7
6
5
4
3
2
1
0
Name
TXRXD7
TXRXD6
TXRXD5
TXRXD4
TXRXD3
TXRXD2
TXRXD1
TXRXD0
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 7~0TXRXD7~TXRXD0: UART Transmit/Receive Data bit 7 ~ bit 0
BRG Register
Bit
7
6
5
4
3
2
1
0
Name
BRGD7
BRGD6
BRGD5
BRGD4
BRGD3
BRGD2
BRGD1
BRGD0
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 7~0BRGD7~BRGD0: Baud Rate values
By programming the BRGH bit in UCR2 Register which allows selection of the
related formula described above and programming the required value in the BRG
register, the required baud ratecan be setup.
Note: Baud rate= fSYS/[64×(N+1)] if BRGH=0.
Baud rate= fSYS/[16×(N+1)] if BRGH=1.
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Baud Rate Generator
To setup the speed of the serial data communication, the UART function contains its own dedicated
baud rate generator. The baud rate is controlled by its own internal free running 8-bit timer, the
period of which is determined by two factors. The first of these is the value placed in the baud rate
register BRG and the second is the value of the BRGH bit with the control register UCR2. The
BRGH bit decides if the baud rate generator is to be used in a high speed mode or low speed mode,
which in turn determines the formula that is used to calculate the baud rate. The value N in the BRG
register which is used in the following baud rate calculation formula determines the division factor.
Note that N is the decimal value placed in the BRG register and has a range of between 0 and 255.
UCR2 BRGH Bit
0
1
Baud Rate (BR)
fSYS / [64 (N+1)]
fSYS / [16 (N+1)]
By programming the BRGH bit which allows selection of the related formula and programming the
required value in the BRG register, the required baud rate can be setup. Note that because the actual
baud rate is determined using a discrete value, N, placed in the BRG register, there will be an error
associated between the actual and requested value. The following example shows how the BRG
register value N and the error value can be calculated.
Calculating the Register and Error Values
For a clock frequency of 4MHz, and with BRGH cleared to zero determine the BRG register value N,
the actual baud rate and the error value for a desired baud rate of 4800.
From the above table the desired baud rate BR = fSYS / [64 (N+1)]
Re-arranging this equation gives N = [fSYS / (BR×64)] - 1
Giving a value for N = [4000000 / (4800×64)] - 1 = 12.0208
To obtain the closest value, a decimal value of 12 should be placed into the BRG register. This gives
an actual or calculated baud rate value of BR = 4000000 / [64×(12 + 1)] = 4808
Therefore the error is equal to (4808 - 4800) / 4800 = 0.16%
The following tables show actual values of baud rate and error values for the two values of BRGH.
Baud
Rate
K/BPS
Baud Rates for BRGH=0
fSYS=4MHz
fSYS=3.579545MHz
BRG
Kbaud
0.3
207
0.300
0.16
185
0.300
0.00
—
—
—
1.2
51
1.202
0.16
46
1.190
-0.83
92
1.203
0.23
BRG
Kbaud
Error
(%)
fSYS=7.159MHz
Error
(%)
BRG
Kbaud
Error
(%)
2.4
25
2.404
0.16
22
2.432
1.32
46
2.380
-0.83
4.8
12
4.808
0.16
11
4.661
-2.90
22
4.863
1.32
9.6
6
8.929
-6.99
5
9.321
-2.90
11
9.332
-2.90
19.2
2
20.833
8.51
2
18.643
-2.90
5
18.643
-2.90
38.4
—
—
—
—
—
—
2
32.286
-2.90
57.6
0
62.500
8.51
0
55.930
-2.90
1
55.930
-2.90
115.2
—
—
—
—
—
—
0
111.859
-2.90
Baud Rates and Error Values for BRGH = 0
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Baud
Rate
K/BPS
Baud Rates for BRGH=0
fSYS=4MHz
fSYS=3.579545MHz
fSYS=7.159MHz
BRG
Kbaud
Error
(%)
BRG
Kbaud
Error
(%)
BRG
Kbaud
Error
(%)
0.3
—
—
—
—
—
—
—
—
—
1.2
207
1.202
0.16
185
1.203
0.23
—
—
—
2.4
103
2.404
0.16
92
2.406
0.23
185
2.406
0.23
4.8
51
4.808
0.16
46
4.76
-0.83
92
4.811
0.23
9.6
25
9.615
0.16
22
9.727
1.32
46
9.520
-0.83
19.2
12
19.231
0.16
11
18.643
-2.90
22
19.454
1.32
38.4
6
35.714
-6.99
5
37.286
-2.90
11
37.286
-2.90
57.6
3
62.5
8.51
3
55.930
-2.90
7
55.930
-2.90
115.2
1
125
8.51
1
111.86
-2.90
3
111.86
-2.90
250
0
250
0
—
—
—
—
—
—
Baud Rates and Error Values for BRGH = 1
UART Setup and Control
For data transfer, the UART function utilizes a non-return-to-zero, more commonly known as NRZ,
format. This is composed of one start bit, eight or nine data bits, and one or two stop bits. Parity
is supported by the UART hardware, and can be setup to be even, odd or no parity. For the most
common data format, 8 data bits along with no parity and one stop bit, denoted as 8, N, 1, is used
as the default setting, which is the setting at power-on. The number of data bits and stop bits, along
with the parity, are setup by programming the corresponding BNO, PRT, PREN, and STOPS bits
in the UCR1 register. The baud rate used to transmit and receive data is setup using the internal
8-bit baud rate generator, while the data is transmitted and received LSB first. Although the UART
transmitter and receiver are functionally independent, they both use the same data format and baud
rate. In all cases stop bits will be used for data transmission.
Enabling/Disabling the UART
The basic on/off function of the internal UART function is controlled using the UARTEN bit in the
UCR1 register. If the UARTEN, TXEN and RXEN bits are set, then these two UART pins will act
as normal TX output pin and RX input pin respectively. If no data is being transmitted on the TX
pin, then it will default to a logic high value.
Clearing the UARTEN bit will disable the TX and RX pins and allow these two pins to be used as
normal I/O or other pin-shared functional pins. When the UART function is disabled the buffer will
be reset to an empty condition, at the same time discarding any remaining residual data. Disabling
the UART will also reset the error and status flags with bits TXEN, RXEN, TXBRK, RXIF, OERR,
FERR, PERR and NF being cleared while bits TIDLE, TXIF and RIDLE will be set. The remaining
control bits in the UCR1, UCR2 and BRG registers will remain unaffected. If the UARTEN bit in
the UCR1 register is cleared while the UART is active, then all pending transmissions and receptions
will be immediately suspended and the UART will be reset to a condition as defined above. If the
UART is then subsequently re-enabled, it will restart again in the same configuration.
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Data, Parity and Stop Bit Selection
The format of the data to be transferred, is composed of various factors such as data bit length,
parity on/off, parity type, address bits and the number of stop bits. These factors are determined by
the setup of various bits within the UCR1 register. The BNO bit controls the number of data bits
which can be set to either 8 or 9, the PRT bit controls the choice of odd or even parity, the PREN
bit controls the parity on/off function and the STOPS bit decides whether one or two stop bits are to
be used. The following table shows various formats for data transmission. The address bit identifies
the frame as an address character. The number of stop bits, which can be either one or two, is
independent of the data length.
Start Bit
Data Bits
Address Bits
Parity Bits
Stop Bit
Example of 8-bit Data Formats
1
8
0
0
1
1
7
0
1
1
1
7
1
0
1
Example of 9-bit Data Formats
1
9
0
0
1
1
8
0
1
1
1
8
1
0
1
Transmitter Receiver Data Format
The following diagram shows the transmit and receive waveforms for both 8-bit and 9-bit data formats.
UART Transmitter
Data word lengths of either 8 or 9 bits, can be selected by programming the BNO bit in the UCR1
register. When BNO bit is set, the word length will be set to 9 bits. In this case the 9th bit, which
is the MSB, needs to be stored in the TX8 bit in the UCR1 register. At the transmitter core lies the
Transmitter Shift Register, more commonly known as the TSR, whose data is obtained from the
transmit data register, which is known as the TXR register. The data to be transmitted is loaded
into this TXR register by the application program. The TSR register is not written to with new data
until the stop bit from the previous transmission has been sent out. As soon as this stop bit has been
transmitted, the TSR can then be loaded with new data from the TXR register, if it is available. It
should be noted that the TSR register, unlike many other registers, is not directly mapped into the
Data Memory area and as such is not available to the application program for direct read/write
operations. An actual transmission of data will normally be enabled when the TXEN bit is set, but
the data will not be transmitted until the TXR register has been loaded with data and the baud rate
generator has defined a shift clock source. However, the transmission can also be initiated by first
loading data into the TXR register, after which the TXEN bit can be set. When a transmission of
data begins, the TSR is normally empty, in which case a transfer to the TXR register will result in
an immediate transfer to the TSR. If during a transmission the TXEN bit is cleared, the transmission
will immediately cease and the transmitter will be reset. The TX output pin will then return to the I/O
or other pin-shared function.
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Transmitting Data
When the UART is transmitting data, the data is shifted on the TX pin from the shift register, with
the least significant bit first. In the transmit mode, the TXR register forms a buffer between the
internal bus and the transmitter shift register. It should be noted that if 9-bit data format has been
selected, then the MSB will be taken from the TX8 bit in the UCR1 register. The steps to initiate a
data transfer can be summarized as follows:
• Make the correct selection of the BNO, PRT, PREN and STOPS bits to define the required word
length, parity type and number of stop bits.
• Setup the BRG register to select the desired baud rate.
• Set the TXEN bit to ensure that the TX pin is used as a UART transmitter pin.
• Access the USR register and write the data that is to be transmitted into the TXR register. Note
that this step will clear the TXIF bit.
• This sequence of events can now be repeated to send additional data.
It should be noted that when TXIF=0, data will be inhibited from being written to the TXR register.
Clearing the TXIF flag is always achieved using the following software sequence:
1. A USR register access
2. A TXR register write execution
The read-only TXIF flag is set by the UART hardware and if set indicates that the TXR register is
empty and that other data can now be written into the TXR register without overwriting the previous
data. If the TEIE bit is set then the TXIF flag will generate an interrupt.
During a data transmission, a write instruction to the TXR register will place the data into the TXR
register, which will be copied to the shift register at the end of the present transmission. When there
is no data transmission in progress, a write instruction to the TXR register will place the data directly
into the shift register, resulting in the commencement of data transmission, and the TXIF bit being
immediately set. When a frame transmission is complete, which happens after stop bits are sent
or after the break frame, the TIDLE bit will be set. To clear the TIDLE bit the following software
sequence is used:
1. A USR register access
2. A TXR register write execution
Note that both the TXIF and TIDLE bits are cleared by the same software sequence.
Transmit Break
If the TXBRK bit is set then break characters will be sent on the next transmission. Break character
transmission consists of a start bit, followed by 13×N ‘0’ bits and stop bits, where N=1, 2, etc. If a
break character is to be transmitted then the TXBRK bit must be first set by the application program,
then cleared to generate the stop bits. Transmitting a break character will not generate a transmit
interrupt. Note that a break condition length is at least 13 bits long. If the TXBRK bit is continually
kept at a logic high level then the transmitter circuitry will transmit continuous break characters.
After the application program has cleared the TXBRK bit, the transmitter will finish transmitting the
last break character and subsequently send out one or two stop bits. The automatic logic highs at the
end of the last break character will ensure that the start bit of the next frame is recognized.
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UART Receiver
The UART is capable of receiving word lengths of either 8 or 9 bits. If the BNO bit is set, the word
length will be set to 9 bits with the MSB being stored in the RX8 bit of the UCR1 register. At the
receiver core lies the Receive Serial Shift Register, commonly known as the RSR. The data which
is received on the RX external input pin, is sent to the data recovery block. The data recovery block
operating speed is 16 times that of the baud rate, while the main receive serial shifter operates at the
baud rate. After the RX pin is sampled for the stop bit, the received data in RSR is transferred to the
receive data register, if the register is empty. The data which is received on the external RX input pin
is sampled three times by a majority detect circuit to determine the logic level that has been placed
onto the RX pin. It should be noted that the RSR register, unlike many other registers, is not directly
mapped into the Data Memory area and as such is not available to the application program for direct
read/write operations.
Receiving Data
When the UART receiver is receiving data, the data is serially shifted in on the external RX input
pin, LSB first. In the read mode, the RXR register forms a buffer between the internal bus and the
receiver shift register. The RXR register is a two byte deep FIFO data buffer, where two bytes can
be held in the FIFO while a third byte can continue to be received. Note that the application program
must ensure that the data is read from RXR before the third byte has been completely shifted
in, otherwise this third byte will be discarded and an overrun error OERR will be subsequently
indicated. The steps to initiate a data transfer can be summarized as follows:
• Make the correct selection of BNO, PRT, PREN and STOPS bits to define the word length, parity
type and number of stop bits.
• Setup the BRG register to select the desired baud rate.
• Set the RXEN bit to ensure that the RX pin is used as a UART receiver pin.
At this point the receiver will be enabled which will begin to look for a start bit.
When a character is received the following sequence of events will occur:
• The RXIF bit in the USR register will be set when RXR register has data available, at least one
more character can be read.
• When the contents of the shift register have been transferred to the RXR register, then if the RIE
bit is set, an interrupt will be generated.
• If during reception, a frame error, noise error, parity error, or an overrun error has been detected,
then the error flags can be set.
The RXIF bit can be cleared using the following software sequence:
1. A USR register access
2. An RXR register read execution
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Receive Break
Any break character received by the UART will be managed as a framing error. The receiver will
count and expect a certain number of bit times as specified by the values programmed into the BNO
and STOPS bits. If the break is much longer than 13 bit times, the reception will be considered as
complete after the number of bit times specified by BNO and STOPS. The RXIF bit is set, FERR
is set, zeros are loaded into the receive data register, interrupts are generated if appropriate and the
RIDLE bit is set. If a long break signal has been detected and the receiver has received a start bit,
the data bits and the invalid stop bit, which sets the FERR flag, the receiver must wait for a valid
stop bit before looking for the next start bit. The receiver will not make the assumption that the
break condition on the line is the next start bit. A break is regarded as a character that contains only
zeros with the FERR flag set. The break character will be loaded into the buffer and no further data
will be received until stop bits are received. It should be noted that the RIDLE read only flag will go
high when the stop bits have not yet been received. The reception of a break character on the UART
registers will result in the following:
• The framing error flag, FERR, will be set.
• The receive data register, RXR, will be cleared.
• The OERR, NF, PERR, RIDLE or RXIF flags will possibly be set.
Idle Status
When the receiver is reading data, which means it will be in between the detection of a start bit and
the reading of a stop bit, the receiver status flag in the USR register, otherwise known as the RIDLE
flag, will have a zero value. In between the reception of a stop bit and the detection of the next start
bit, the RIDLE flag will have a high value, which indicates the receiver is in an idle condition.
Receiver Interrupt
The read only receive interrupt flag RXIF in the USR register is set by an edge generated by the
receiver. An interrupt is generated if RIE=1, when a word is transferred from the Receive Shift
Register, RSR, to the Receive Data Register, RXR. An overrun error can also generate an interrupt if
RIE=1.
Managing Receiver Errors
Several types of reception errors can occur within the UART module, the following section describes
the various types and how they are managed by the UART.
Overrun Error – OERR Flag
The RXR register is composed of a two byte deep FIFO data buffer, where two bytes can be held
in the FIFO register, while a third byte can continue to be received. Before this third byte has been
entirely shifted in, the data should be read from the RXR register. If this is not done, the overrun
error flag OERR will be consequently indicated.
In the event of an overrun error occurring, the following will happen:
• The OERR flag in the USR register will be set.
• The RXR contents will not be lost.
• The shift register will be overwritten.
• An interrupt will be generated if the RIE bit is set.
The OERR flag can be cleared by an access to the USR register followed by a read to the RXR
register.
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Noise Error – NF Flag
Over-sampling is used for data recovery to identify valid incoming data and noise. If noise is
detected within a frame the following will occur:
• The read only noise flag, NF, in the USR register will be set on the rising edge of the RXIF bit.
• Data will be transferred from the Shift register to the RXR register.
• No interrupt will be generated. However this bit rises at the same time as the RXIF bit which
itself generates an interrupt.
Note that the NF flag is reset by a USR register read operation followed by an RXR register read operation.
Framing Error – FERR Flag
The read only framing error flag, FERR, in the USR register, is set if a zero is detected instead of
stop bits. If two stop bits are selected, both stop bits must be high, otherwise the FERR flag will be
set. The FERR flag is buffered along with the received data and is cleared on any reset.
Parity Error – PERR Flag
The read only parity error flag, PERR, in the USR register, is set if the parity of the received word is
incorrect. This error flag is only applicable if the parity is enabled, PREN = 1, and if the parity type,
odd or even is selected. The read only PERR flag is buffered along with the received data bytes. It is
cleared on any reset. It should be noted that the FERR and PERR flags are buffered along with the
corresponding word and should be read before reading the data word.
UART Module Interrupt Structure
Several individual UART conditions can generate a UART interrupt. When these conditions exist,
a low pulse will be generated to get the attention of the microcontroller. These conditions are a
transmitter data register empty, transmitter idle, receiver data available, receiver overrun, address
detect and an RX pin wake-up. When any of these conditions are created, if the global interrupt
enable bit, multi-function interrupt enable bit and its corresponding interrupt control bit are enabled
and the stack is not full, the program will jump to its corresponding interrupt vector where it can
be serviced before returning to the main program. Four of these conditions have the corresponding
USR register flags which will generate a UART interrupt if its associated interrupt enable control bit
in the UCR2 register is set. The two transmitter interrupt conditions have their own corresponding
enable control bits, while the two receiver interrupt conditions have a shared enable control bit.
These enable bits can be used to mask out individual UART interrupt sources.
The address detect condition, which is also a UART interrupt source, does not have an associated
flag, but will generate a UART interrupt when an address detect condition occurs if its function
is enabled by setting the ADDEN bit in the UCR2 register. An RX pin wake-up, which is also a
UART interrupt source, does not have an associated flag, but will generate a UART interrupt if the
microcontroller is woken up from IDLE0 or SLEEP mode by a falling edge on the RX pin, if the
WAKE and RIE bits in the UCR register are set. Note that in the event of an RX wake-up interrupt
occurring, there will be a certain period of delay, commonly known as the System Start-up Time, for
the oscillator to restart and stabilize before the system resumes normal operation.
Note that the USR register flags are read only and cannot be cleared or set by the application
program, neither will they be cleared when the program jumps to the corresponding interrupt
servicing routine, as is the case for some of the other interrupts. The flags will be cleared
automatically when certain actions are taken by the UART, the details of which are given in the
UART register section. The overall UART interrupt can be disabled or enabled by the related
interrupt enable control bits in the interrupt control registers of the microcontroller to decide whether
the interrupt requested by the UART module is masked out or allowed.
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USR Registe�
UCR� Registe�
T�ansmitte� Empt�
Flag TXIF
TEIE
T�ansmitte� Idle
Flag TIDLE
TIIE
0
1
RIE
0
1
Receive� Ove���n
Flag OERR
OR
Receive� Data
Available RXIF
RX Pin
Wake-�p
WAKE
ADDEN
0
1
UART Inte���pt
Req�est Flag
UIF
MFI1
Registe�
UIE
INTC0
Registe�
INTC1
Registe�
EMI
MF1E
0
1
0
1
0
1
RX7 if BNO=0
RX8 if BNO=1
UCR� Registe�
UART Interrupt Scheme
Address Detect Mode
Setting the Address Detect Mode bit, ADDEN, in the UCR2 register, enables this special mode. If
this bit is enabled then an additional qualifier will be placed on the generation of a Receiver Data
Available interrupt, which is requested by the RXIF flag. If the ADDEN bit is enabled, then when
data is available, an interrupt will only be generated, if the highest received bit has a high value.
Note that the MFnE, UIE and EMI interrupt enable bits must also be enabled for correct interrupt
generation. This highest address bit is the 9th bit if BNO=1 or the 8th bit if BNO=0. If this bit
is high, then the received word will be defined as an address rather than data. A Data Available
interrupt will be generated every time the last bit of the received word is set. If the ADDEN bit
is not enabled, then a Receiver Data Available interrupt will be generated each time the RXIF
flag is set, irrespective of the data last bit status. The address detect mode and parity enable are
mutually exclusive functions. Therefore if the address detect mode is enabled, then to ensure correct
operation, the parity function should be disabled by resetting the parity enable bit to zero.
ADDEN
Bit 9 if BNO=1,
Bit 8 if BNO=0
UART Interrupt
Generated
0
√
1
√
0
×
1
√
0
1
ADDEN Bit Function
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UART Module Power Down and Wake-up
When the MCU is in the Power Down Mode, the UART will cease to function. When the device
enters the Power Down Mode, all clock sources to the module are shutdown. If the MCU enters the
Power Down Mode while a transmission is still in progress, then the transmission will be paused
until the UART clock source derived from the microcontroller is activated. In a similar way, if the
MCU enters the Power Down Mode while receiving data, then the reception of data will likewise
be paused. When the MCU enters the IDLE or SLEEP Mode, note that the USR, UCR1, UCR2,
transmit and receive registers, as well as the BRG register will not be affected. It is recommended
to make sure first that the UART data transmission or reception has been finished before the
microcontroller enters the IDLE or SLEEP mode.
The UART function contains a receiver RX pin wake-up function, which is enabled or disabled
by the WAKE bit in the UCR2 register. If this bit, along with the UART enable bit, UARTEN, the
receiver enable bit, RXEN and the receiver interrupt bit, RIE, are all set before the MCU enters the IDLE0 or SLEEP Mode, then a falling edge on the RX pin will wake up the MCU from the IDLE0
or SLEEP Mode. Note that as it takes certain system clock cycles after a wake-up, before normal
microcontroller operation resumes, any data received during this time on the RX pin will be ignored.
For a UART wake-up interrupt to occur, in addition to the bits for the wake-up being set, the global
interrupt enable bit, EMI, and the UART interrupt enable bit, UIE, must also be set. If these two bits
are not set then only a wake up event will occur and no interrupt will be generated. Note also that
as it takes certain system clock cycles after a wake-up before normal microcontroller resumes, the
UART interrupt will not be generated until after this time has elapsed.
IR Modulation Interface
The UART interface has an integrated IR modulation interface. Infrared modulation frequency
control by register IRCTRL0, its value is any integer between 0 and 127.
Infrared modulation: When TXD = 0 only, the IR modulation will produce infrared mixing and
output data. To meet the needs of both PNP and NPN infrared driver tube, located in the register
IRCTRL0 bit7 IRTC, control the polarity of the output of the infrared modulation. IRTC = 0 for
positive polarity output, suitable for PNP transistor driver; IRTC = 1 for a negative output, suitable
for the NPN driver. See below:
Fca���
TXD
1
0
1
0
0
1
1
1
0
0
1
0
1
IR TXD
(IRTC=0)
IR TXD
(IRTC=1)
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IRCTRL0 Register
Bit
7
6
5
4
3
2
1
0
Name
IRTC
IRDC6
IRDC5
IRDC4
IRDC3
IRDC2
IRDC1
IRDC0
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 7IRTC: IR modulation output polarity select
0: Negative
1: Positive
Bit 6~0IRDC6~IRDC0: IR modulation frequency divider coefficient
Fcarry = (fSYS/(IRDC+1))/2
IRCTRL1 Register
Bit
7
6
5
4
3
2
1
0
Name
—
—
—
—
—
—
—
IRME0
R/W
—
—
—
—
—
—
—
R/W
POR
—
—
—
—
—
—
—
0
Bit 7~1
Unimplemented, read as "0"
Bit 0IRME0: UART0 TX IR modulation control
0: UART0 TX IR modulation disable
1: UART0 TX IR modulation enable
Interrupts
Interrupts are an important part of any microcontroller system. When an external event or an
internal function such as a Timer Module or an A/D converter requires microcontroller attention,
their corresponding interrupt will enforce a temporary suspension of the main program allowing the
microcontroller to direct attention to their respective needs. The device contains several external
interrupt and internal interrupts functions. The external interrupts are generated by the action of the
external INT0~INT1 pins, while the internal interrupts are generated by various internal functions
such as the TMs, Time Base, LVD, EEPROM and the A/D converter.
Interrupt Registers
Overall interrupt control, which basically means the setting of request flags when certain
microcontroller conditions occur and the setting of interrupt enable bits by the application program,
is controlled by a series of registers, located in the Special Purpose Data Memory. The first is the
INTC0~INTC2 registers which setup the primary interrupts, the second is the MFI0~MFI3 registers
which setup the Multi-function interrupts. Finally there is an INTEG register to setup the external
interrupt trigger edge type.
Each register contains a number of enable bits to enable or disable individual registers as well as
interrupt flags to indicate the presence of an interrupt request. The naming convention of these
follows a specific pattern. First is listed an abbreviated interrupt type, then the (optional) number of
that interrupt followed by either an "E" for enable/disable bit or "F" for request flag.
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Function
Enable Bit
Request Flag
Notes
EMI
—
—
INTn Pin
INTnE
INTnF
n=0~1
Multi-function
MFnE
MFnF
n=0~3
A/D Converter
ADE
ADF
—
Time Base
Global
TBnE
TBnF
n=0~1
LVD
LVE
LVF
—
EEPROM
DEE
DEF
—
SIM
SIE
SIF
—
I2CTOE
I2CTOF
—
UIE
UIF
—
I C time out
2
UART
TM
TnPE
TnPF
TnAE
TnAF
n=0~2
Interrupt Register Bit Naming Conventions
Bit
Register
Name
7
INTEG
—
—
INTC0
—
MF0F
INTC1
MF1F
TB1F
INTC2
—
—
6
5
4
3
2
1
0
—
—
INT1S1
INT1S0
INT0S1
INT0S0
INT1F
INT0F
MF0E
INT1E
INT0E
EMI
TB0F
ADF
MF1E
TB1E
TB0E
ADE
MF3F
MF2F
—
—
MF3E
MF2E
MFI0
—
—
T0AF
T0PF
—
—
T0AE
T0PE
MFI1
UIF
SIF
DEF
LVF
UIE
SIE
DEE
LVE
MFI2
I2CTOF
—
T1AF
T1PF
I2CTOE
—
T1AE
T1PE
MFI3
—
—
T2AF
T2PF
—
—
T2AE
T2PE
Interrupt Register Contents
INTEG Register
Bit
7
6
5
4
3
2
1
0
Name
—
—
—
—
INT1S1
INT1S0
INT0S1
INT0S0
R/W
—
—
—
—
R/W
R/W
R/W
R/W
POR
—
—
—
—
0
0
0
0
Bit 7~4
Unimplemented, read as "0"
Bit 3~2INT1S1~INT1S0: interrupt edge control for INT1 pin
00: Disable
01: Rising edge
10: Falling edge
11: Rising and falling edges
Bit 1~0INT0S1~INT0S0: interrupt edge control for INT0 pin
00: Disable
01: Rising edge
10: Falling edge
11: Rising and falling edges
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INTC0 Register
Bit
7
6
5
4
3
2
1
0
Name
—
MF0F
INT1F
INT0F
MF0E
INT1E
INT0E
EMI
R/W
—
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
—
0
0
0
0
0
0
0
Bit 7
Unimplemented, read as "0"
Bit 6MF0F: Multi-function interrupt 0 request flag
0: No request
1: Interrupt request
Bit 5INT1F: INT1 interrupt request flag
0: No request
1: Interrupt request
Bit 4INT0F: INT0 interrupt request flag
0: No request
1: Interrupt request
Bit 3MF0E: Multi-function interrupt 0 control
0: Disable
1: Enable
Bit 2INT1E: INT1 interrupt control
0: Disable
1: Enable
Bit 1INT0E: INT0 interrupt control
0: Disable
1: Enable
Bit 0EMI: Global interrupt control
0: Disable
1: Enable
INTC1 Register
Bit
7
6
5
4
3
2
1
0
Name
MF1F
TB1F
TB0F
ADF
MF1E
TB1E
TB0E
ADE
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
0
0
0
0
0
0
0
Bit 7MF1F: Multi-function interrupt 1 request flag
0: No request
1: Interrupt request
Bit 6TB1F: Time Base 1 interrupt request flag
0: No request
1: Interrupt request
Bit 5TB0F: Time Base 0 interrupt request flag
0: No request
1: Interrupt request
Bit 4ADF: A/D Converter interrupt request flag
0: No request
1: Interrupt request
Bit 3MF1E: Multi-function interrupt 1 control
0: Disable
1: Enable
Bit 2TB1E: Time Base 1 interrupt control
0: Disable
1: Enable
Bit 1TB0E: Time Base 0 interrupt control
0: Disable
1: Enable
Bit 0ADE: A/D Converter interrupt control
0: Disable
1: Enable
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INTC2 Register
Bit
7
6
5
4
3
2
1
0
Name
—
—
MF3F
MF2F
—
—
MF3E
MF2E
R/W
—
—
R/W
R/W
—
—
R/W
R/W
POR
—
—
0
0
—
—
0
0
Bit 7~6
Unimplemented, read as "0"
Bit 5MF3F: Multi-function interrupt 3 request flag
0: No request
1: Interrupt request
Bit 4MF2F: Multi-function interrupt 2 request flag
0: No request
1: Interrupt request
Bit 3~2
Unimplemented, read as "0"
Bit 1MF3E: Multi-function interrupt 3 control
0: Disable
1: Enable
Bit 0MF2E: Multi-function interrupt 2 control
0: Disable
1: Enable
MFI0 Register
Bit
7
6
5
4
3
2
1
0
Name
—
—
T0AF
T0PF
—
—
T0AE
T0PE
R/W
—
—
R/W
R/W
—
—
R/W
R/W
POR
—
—
0
0
—
—
0
0
Bit 7~6
Unimplemented, read as "0"
Bit 5T0AF: TM0 Comparator A match interrupt request flag
0: No request
1: Interrupt request
Bit 4T0PF: TM0 Comparator P match interrupt request flag
0: No request
1: Interrupt request
Bit 3~2
Unimplemented, read as "0"
Bit 1T0AE: TM0 Comparator A match interrupt control
0: Disable
1: Enable
Bit 0T0PE: TM0 Comparator P match interrupt control
0: Disable
1: Enable
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MFI1 Register
Bit
7
6
5
4
3
2
1
0
Name
UIF
SIF
DEF
LVF
UIE
SIE
DEE
LVE
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 7UIF: UART interrupt request flag
0: No request
1: Interrupt request
Bit 6SIF: SIM interrupt request flag
0: No request
1: Interrupt request
Bit 5DEF: Data EEPROM interrupt request flag
0: No request
1: Interrupt request
Bit 4LVF: LVD interrupt request flag
0: No request
1: Interrupt request
Bit 3UIE: UART interrupt control
0: Disable
1: Enable
Bit 2SIE: SIM interrupt control
0: Disable
1: Enable
Bit 1DEE: Data EEPROM interrupt control
0: Disable
1: Enable
Bit 0LVE: LVD interrupt control
0: Disable
1: Enable
MFI2 Register
Bit
7
6
5
4
3
2
1
0
Name
I2CTOF
—
T1AF
T1PF
I2CTOE
—
T1AE
T1PE
R/W
R/W
—
R/W
R/W
R/W
—
R/W
R/W
POR
0
—
0
0
0
—
0
0
Bit 7I2CTOF: I2C Time Out interrupt request flag
0: No request
1: Interrupt request
Bit 6
Unimplemented, read as "0"
Bit 5T1AF: TM1 Comparator A match interrupt request flag
0: No request
1: Interrupt request
Bit 4T1PF: TM1 Comparator P match interrupt request flag
0: No request
1: Interrupt request
Bit 3I2CTOE: I2C Time Out interrupt control
0: Disable
1: Enable
Bit 2
Unimplemented, read as "0"
Bit 1T1AE: TM1 Comparator A match interrupt control
0: Disable
1: Enable
Bit 0T1PE: TM1 Comparator P match interrupt control
0: Disable
1: Enable
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MFI3 Register
Bit
7
6
5
4
3
2
1
0
Name
—
—
T2AF
T2PF
—
—
T2AE
T2PE
R/W
—
—
R/W
R/W
—
—
R/W
R/W
POR
—
—
0
0
—
—
0
0
Bit 7~6
Unimplemented, read as "0"
Bit 5T2AF: TM2 Comparator A match interrupt request flag
0: No request
1: Interrupt request
Bit 4T2PF: TM2 Comparator P match interrupt request flag
0: No request
1: Interrupt request
Bit 3~2
Unimplemented, read as "0"
Bit 1T2AE: TM2 Comparator A match interrupt control
0: Disable
1: Enable
Bit 0T2PE: TM2 Comparator P match interrupt control
0: Disable
1: Enable
Interrupt Operation
When the conditions for an interrupt event occur, such as a TM Comparator P, Comparator A match
or A/D conversion completion etc, the relevant interrupt request flag will be set. Whether the request
flag actually generates a program jump to the relevant interrupt vector is determined by the condition
of the interrupt enable bit. If the enable bit is set high then the program will jump to its relevant
vector; if the enable bit is zero then although the interrupt request flag is set an actual interrupt will
not be generated and the program will not jump to the relevant interrupt vector. The global interrupt
enable bit, if cleared to zero, will disable all interrupts.
When an interrupt is generated, the Program Counter, which stores the address of the next instruction
to be executed, will be transferred onto the stack. The Program Counter will then be loaded with a
new address which will be the value of the corresponding interrupt vector. The microcontroller will
then fetch its next instruction from this interrupt vector. The instruction at this vector will usually
be a "JMP" which will jump to another section of program which is known as the interrupt service
routine. Here is located the code to control the appropriate interrupt. The interrupt service routine
must be terminated with a "RETI", which retrieves the original Program Counter address from
the stack and allows the microcontroller to continue with normal execution at the point where the
interrupt occurred.
The various interrupt enable bits, together with their associated request flags, are shown in the
accompanying diagrams with their order of priority. Some interrupt sources have their own
individual vector while others share the same multi-function interrupt vector. Once an interrupt
subroutine is serviced, all the other interrupts will be blocked, as the global interrupt enable bit,
EMI bit will be cleared automatically. This will prevent any further interrupt nesting from occurring.
However, if other interrupt requests occur during this interval, although the interrupt will not be
immediately serviced, the request flag will still be recorded.
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If an interrupt requires immediate servicing while the program is already in another interrupt service
routine, the EMI bit should be set after entering the routine, to allow interrupt nesting. If the stack
is full, the interrupt request will not be acknowledged, even if the related interrupt is enabled, until
the Stack Pointer is decremented. If immediate service is desired, the stack must be prevented from
becoming full. In case of simultaneous requests, the accompanying diagram shows the priority that
is applied. All of the interrupt request flags when set will wake-up the device if it is in SLEEP or
IDLE Mode, however to prevent a wake-up from occurring the corresponding flag should be set
before the device is in SLEEP or IDLE Mode.
Legend
xxF
Request Flag – no auto reset in ISR
EMI auto disabled in ISR
xxF Request Flag – auto reset in ISR
Interrupt Request
Flags
Name
xxE Enable Bit
Enable
Bits
Master
Enable
Vector
INT0 Pin
INT0F
INT0E
EMI
04H
Request
Flags
Enable
Bits
INT1 Pin
INT1F
INT1E
EMI
08H
TM0 P
T0PF
T0PE
M. Funct. 0
MF0F
MF0E
EMI
0CH
TM0 A
T0AF
T0AE
A/D
ADF
ADE
EMI
10H
Time Base 0 TB0F
TB0E
EMI
14H
Time Base 1 TB1F
TB1E
EMI
18H
M. Funct. 1
MF1F
MF1E
EMI
1CH
M. Funct. 2
MF2F
MF2E
EMI
20H
M. Funct. 3
MF3F
MF3E
EMI
24H
Interrupt
Name
LVD
LVF
LVE
EEPROM
DEF
DEE
UART
UIF
UIE
SIM
SIF
SIE
I2CTO
I2CTOF
I2CTOE
TM1 P
T1PF
T1PE
TM1 A
T1AF
T1AE
TM2 P
T2PF
T2PE
TM2 A
T2AF
T2AE
Interrupts contained within
Multi-Function Interrupts
Priority
High
Low
Interrupt Structure
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External Interrupt
The external interrupts are controlled by signal transitions on the pins INT0~INT1. An external
interrupt request will take place when the external interrupt request flags, INT0F~INT1F, are set,
which will occur when a transition, whose type is chosen by the edge select bits, appears on the
external interrupt pins. To allow the program to branch to its respective interrupt vector address, the
global interrupt enable bit, EMI, and respective external interrupt enable bit, INT0E~INT1E, must
first be set. Additionally the correct interrupt edge type must be selected using the INTEG register to
enable the external interrupt function and to choose the trigger edge type. As the external interrupt
pins are pin-shared with I/O pins, they can only be configured as external interrupt pins if their
external interrupt enable bit in the corresponding interrupt register has been set. The pin must also
be setup as an input by setting the corresponding bit in the port control register. When the interrupt
is enabled, the stack is not full and the correct transition type appears on the external interrupt pin,
a subroutine call to the external interrupt vector, will take place. When the interrupt is serviced, the
external interrupt request flags, INT0F~INT1F, will be automatically reset and the EMI bit will be
automatically cleared to disable other interrupts. Note that any pull-high resistor selections on the
external interrupt pins will remain valid even if the pin is used as an external interrupt input. The
INTEG register is used to select the type of active edge that will trigger the external interrupt. A
choice of either rising or falling or both edge types can be chosen to trigger an external interrupt.
Note that the INTEG register can also be used to disable the external interrupt function.
A/D Converter Interrupt
The A/D Converter Interrupt is controlled by the termination of an A/D conversion process. An A/D
Converter Interrupt request will take place when the A/D Converter Interrupt request flag, ADF, is
set, which occurs when the A/D conversion process finishes. To allow the program to branch to its
respective interrupt vector address, the global interrupt enable bit, EMI, and A/D Interrupt enable bit,
ADE, must first be set. When the interrupt is enabled, the stack is not full and the A/D conversion
process has ended, a subroutine call to the A/D Converter Interrupt vector, will take place. When the
interrupt is serviced, the A/D Converter Interrupt flag, ADF, will be automatically cleared. The EMI
bit will also be automatically cleared to disable other interrupts.
Multi-function Interrupt
Within this device there are up to four Multi-function interrupts. Unlike the other independent
interrupts, these interrupts have no independent source, but rather are formed from other existing
interrupt sources, namely the TM Interrupts, LVD interrupt, UART interrupt, SIM Interrupt, I2C time
out Interrupt and EEPROM Interrupt.
A Multi-function interrupt request will take place when any of the Multi-function interrupt request
flags, MFnF are set. The Multi-function interrupt flags will be set when any of their included
functions generate an interrupt request flag. To allow the program to branch to its respective interrupt
vector address, when the Multi-function interrupt is enabled and the stack is not full, and either one
of the interrupts contained within each of Multi-function interrupt occurs, a subroutine call to one of
the Multi-function interrupt vectors will take place. When the interrupt is serviced, the related MultiFunction request flag will be automatically reset and the EMI bit will be automatically cleared to
disable other interrupts.
However, it must be noted that, although the Multi-function Interrupt flags will be automatically
reset when the interrupt is serviced, the request flags from the original source of the Multi-function
interrupts, namely the TM Interrupts, LVD interrupt, UART interrupt, SIM Interrupt, I2C time out
Interrupt and EEPROM Interrupt will not be automatically reset and must be manually reset by the
application program.
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Serial Interface Module Interrupt
The Serial Interface Module Interrupt, also known as the SIM interrupt, is contained within the
Multi-function Interrupt. An SIM Interrupt request will take place when the SIM Interrupt request
flag, SIF, is set, which occurs when a byte of data has been received or transmitted by the SIM
interface. To allow the program to branch to its respective interrupt vector address, the global
interrupt enable bit, EMI, and the Serial Interface Interrupt enable bit, SIE, and Muti-function
interrupt enable bits, must first be set. When the interrupt is enabled, the stack is not full and a byte
of data has been transmitted or received by the SIM interface, a subroutine call to the respective
Multi-function Interrupt vector, will take place. When the Serial Interface Interrupt is serviced, the
EMI bit will be automatically cleared to disable other interrupts, however only the Multi-function
interrupt request flag will be also automatically cleared. As the SIF flag will not be automatically
cleared, it has to be cleared by the application program.
Time Base Interrupts
The function of the Time Base Interrupts is to provide regular time signal in the form of an internal
interrupt. They are controlled by the overflow signals from their respective timer functions. When
these happens their respective interrupt request flags, TB0F or TB1F will be set. To allow the
program to branch to their respective interrupt vector addresses, the global interrupt enable bit, EMI
and Time Base enable bits, TB0E or TB1E, must first be set. When the interrupt is enabled, the stack
is not full and the Time Base overflows, a subroutine call to their respective vector locations will
take place. When the interrupt is serviced, the respective interrupt request flag, TB0F or TB1F, will
be automatically reset and the EMI bit will be cleared to disable other interrupts.
The purpose of the Time Base Interrupt is to provide an interrupt signal at fixed time periods. Their
clock sources originate from the internal clock source fTB. This fTB input clock passes through a
divider, the division ratio of which is selected by programming the appropriate bits in the TBC
register to obtain longer interrupt periods whose value ranges. The clock source that generates fTB,
which in turn controls the Time Base interrupt period, can originate from several different sources,
as shown in the System Operating Mode section.
      Time Base Interrupt
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TBC Register
Bit
7
6
5
4
3
2
1
0
Name
TBON
TBCK
TB11
TB10
LXTLP
TB02
TB01
TB00
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
0
1
1
0
1
1
1
Bit 7TBON: TB0 and TB1 Control
0: Disable
1: Enable
Bit 6TBCK: Select fTB Clock
0: fSUB
1: fSYS/4
Bit 5~4TB11~TB10: Select Time Base 1 Time-out Period
00: 4096/fTB
01: 8192/fTB
10: 16384/fTB
11: 32768/fTB
Bit 3LXTLP: LXT Low Power Control
0: Quick Start Mode
1: Low Power Mode
Bit 2~0TB02~TB00: Select Time Base 0 Time-out Period
000: 256/fTB
001: 512/fTB
010: 1024/fTB
011: 2048/fTB
100: 4096/fTB
101: 8192/fTB
110: 16384/fTB
111: 32768/fTB
I2C Time Out Interrupt
The I2C Time Out Interrupt operates is contained within the Multi-function Interrupt. An I2C Time
Out Interrupt request will take place when the I2C Time Out Interrupt request flag, I2CTOF, is
set, which occurs when an I2C time-out counter overflows. To allow the program to branch to its
respective interrupt vector address, the global interrupt enable bit, EMI, I2C time out interrupt enable
bit, I2CTOE, and associated Multi-function interrupt enable bit, must first be set. When the interrupt
is enabled, the stack is not full and an I2C time-out counter overflow occurs, a subroutine call to
the respective Multi-function Interrupt, will take place. When the I2C time out interrupt is serviced,
the EMI bit will be automatically cleared to disable other interrupts, however only the Multifunction interrupt request flag will be also automatically cleared. As the I2CTOF flag will not be
automatically cleared, it has to be cleared by the application program.
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UART Interrupt
The UART interrupt is contained within the Multi-function Interrupt. Several individual UART
conditions can generate a UART interrupt. When these conditions exist, a low pulse will be
generated to get the attention of the microcontroller. These conditions are a transmitter data register
empty, transmitter idle, receiver data available, receiver overrun, address detect and an RX pin
wake-up. To allow the program to branch to the respective interrupt vector addresses, the global
interrupt enable bit, EMI, multi-function enable bit, MFnE and UART interrupt enable bit, UIE,
must first be set. When the interrupt is enabled, the stack is not full and any of these conditions are
created, a subroutine call to the respective Multi-function Interrupt vector, will take place. When the
interrupt is serviced, the EMI bit will be automatically cleared to disable other interrupts, the Multifunction interrupt request flag will be also automatically cleared. However, the USR register flags
will be cleared automatically when certain actions are taken by the UART, the details of which are
given in the UART section.
EEPROM Interrupt
The EEPROM interrupt is contained within the Multi-function Interrupt. An EEPROM Interrupt
request will take place when the EEPROM Interrupt request flag, DEF, is set, which occurs
when an EEPROM Write cycle ends. To allow the program to branch to its respective interrupt
vector address, the global interrupt enable bit, EMI, and EEPROM Interrupt enable bit, DEE, and
associated Multi-function interrupt enable bit, must first be set. When the interrupt is enabled, the
stack is not full and an EEPROM Write cycle ends, a subroutine call to the respective EEPROM
Interrupt vector will take place. When the EEPROM Interrupt is serviced, the EMI bit will be
automatically cleared to disable other interrupts, however only the Multi-function interrupt request
flag will be also automatically cleared. As the DEF flag will not be automatically cleared, it has to be
cleared by the application program.
LVD Interrupt
The Low Voltage Detector Interrupt is contained within the Multi-function Interrupt. An LVD
Interrupt request will take place when the LVD Interrupt request flag, LVF, is set, which occurs
when the Low Voltage Detector function detects a low power supply voltage. To allow the program
to branch to its respective interrupt vector address, the global interrupt enable bit, EMI, Low Voltage
Interrupt enable bit, LVE, and associated Multi-function interrupt enable bit, must first be set. When
the interrupt is enabled, the stack is not full and a low voltage condition occurs, a subroutine call to
the Multi-function Interrupt vector, will take place. When the Low Voltage Interrupt is serviced, the
EMI bit will be automatically cleared to disable other interrupts, however only the Multi-function
interrupt request flag will be also automatically cleared. As the LVF flag will not be automatically
cleared, it has to be cleared by the application program.
TM Interrupts
The Compact and Periodic Type TMs have two interrupts each. All of the TM interrupts are
contained within the Multi-function Interrupts. For each of the Compact and Periodic Type TMs
there are two interrupt request flags TnPF and TnAF and two enable bits TnPE and TnAE. A TM
interrupt request will take place when any of the TM request flags are set, a situation which occurs
when a TM comparator P or A match situation happens.
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To allow the program to branch to its respective interrupt vector address, the global interrupt enable
bit, EMI, respective TM Interrupt enable bit, and relevant Multi-function Interrupt enable bit, MFnE,
must first be set. When the interrupt is enabled, the stack is not full and a TM comparator match
situation occurs, a subroutine call to the relevant Multi-function Interrupt vector locations, will take
place. When the TM interrupt is serviced, the EMI bit will be automatically cleared to disable other
interrupts, however only the related MFnF flag will be automatically cleared. As the TM interrupt
request flags will not be automatically cleared, they have to be cleared by the application program.
Interrupt Wake-up Function
Each of the interrupt functions has the capability of waking up the microcontroller when in the
SLEEP or IDLE Mode. A wake-up is generated when an interrupt request flag changes from low to
high and is independent of whether the interrupt is enabled or not. Therefore, even though the device
is in the SLEEP or IDLE Mode and its system oscillator stopped, situations such as external edge
transitions on the external interrupt pins or a low power supply voltage may cause their respective
interrupt flag to be set high and consequently generate an interrupt. Care must therefore be taken if
spurious wake-up situations are to be avoided. If an interrupt wake-up function is to be disabled then
the corresponding interrupt request flag should be set high before the device enters the SLEEP or
IDLE Mode. The interrupt enable bits have no effect on the interrupt wake-up function.
Programming Considerations
By disabling the relevant interrupt enable bits, a requested interrupt can be prevented from being
serviced, however, once an interrupt request flag is set, it will remain in this condition in the
interrupt register until the corresponding interrupt is serviced or until the request flag is cleared by
the application program.
Where a certain interrupt is contained within a Multi-function interrupt, then when the interrupt
service routine is executed, as only the Multi-function interrupt request flags, MFnF, will be
automatically cleared, the individual request flag for the function needs to be cleared by the
application program.
It is recommended that programs do not use the "CALL" instruction within the interrupt service
subroutine. Interrupts often occur in an unpredictable manner or need to be serviced immediately.
If only one stack is left and the interrupt is not well controlled, the original control sequence will be
damaged once a CALL subroutine is executed in the interrupt subroutine.
Every interrupt has the capability of waking up the microcontroller when it is in SLEEP or IDLE
Mode, the wake up being generated when the interrupt request flag changes from low to high. If it is
required to prevent a certain interrupt from waking up the microcontroller then its respective request
flag should be first set high before enter SLEEP or IDLE Mode.
As only the Program Counter is pushed onto the stack, then when the interrupt is serviced, if the
contents of the accumulator, status register or other registers are altered by the interrupt service
program, their contents should be saved to the memory at the beginning of the interrupt service
routine. To return from an interrupt subroutine, either a RET or RETI instruction may be executed.
The RETI instruction in addition to executing a return to the main program also automatically sets
the EMI bit high to allow further interrupts. The RET instruction however only executes a return to
the main program leaving the EMI bit in its present zero state and therefore disabling the execution
of further interrupts.
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Low Voltage Detector – LVD
Each device has a Low Voltage Detector function, also known as LVD. This enabled the device to
monitor the power supply voltage, VDD, and provide a warning signal should it fall below a certain
level. This function may be especially useful in battery applications where the supply voltage will
gradually reduce as the battery ages, as it allows an early warning battery low signal to be generated.
The Low Voltage Detector also has the capability of generating an interrupt signal.
LVD Register
The Low Voltage Detector function is controlled using a single register with the name LVDC. Three
bits in this register, VLVD2~VLVD0, are used to select one of eight fixed voltages below which a
low voltage conditionwill be determined. A low voltage condition is indicatedwhen the LVDO bit is
set. If the LVDO bit is low, this indicates that the VDD voltage is above the preset low voltage value.
The LVDEN bit is used to control the overall on/off function of the low voltage detector. Setting the
bit high will enable the low voltage detector. Clearing the bit to zero will switch off the internal low
voltage detector circuits. As the low voltage detector will consume a certain amount of power, it may
be desirable to switch off the circuit when not in use, an important consideration in power sensitive
battery powered applications.
LVDC Register
Bit
7
6
5
4
3
2
1
0
Name
—
—
LVDO
LVDEN
—
VLVD2
VLVD1
VLVD0
R/W
—
—
R
R/W
—
R/W
R/W
R/W
POR
—
—
0
0
—
0
0
0
Bit 7~6
Unimplemented, read as "0"
Bit 5LVDO: LVD Output Flag
0: No Low Voltage Detect
1: Low Voltage Detect
Bit 4LVDEN: Low Voltage Detector Control
0: Disable
1: Enable
Bit 3
Unimplemented, read as "0"
Bit 2~0VLVD2~VLVD0: Select LVD Voltage
000: 2.0V
001: 2.2V
010: 2.4V
011: 2.7V
100: 3.0V
101: 3.3V
110: 3.6V
111: 4.0V
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Body Fat Scale 8-Bit Flash MCU
LVD Operation
The Low Voltage Detector function operates by comparing the power supply voltage, VDD, with a
pre-specified voltage level stored in the LVDC register. This has a range of between 2.0V and 4.0V.
When the power supply voltage, VDD, falls below this pre-determined value, the LVDO bit will be
set high indicating a low power supply voltage condition. The Low Voltage Detector function is
supplied by a reference voltage, which will be automatically enabled. When the device is powered
down the low voltage detector will remain active if the LVDEN bit is high. After enabling the Low
Voltage Detector, a time delay tLVDS should be allowed for the circuitry to stabilise before reading the
LVDO bit. Note also that as the VDD voltage may rise and fall rather slowly, at the voltage nears that
of VLVD, there may be multiple bit LVDO transitions.
LVD Operation
The Low Voltage Detector also has its own interrupt which is contained within one of the Multifunction interrupts, providing an alternative means of low voltage detection, in addition to polling
the LVDO bit. The interrupt will only be generated after a delay of tLVD after the LVDO bit has been
set high by a low voltage condition. When the device is powered down the Low Voltage Detector
will remain active if the LVDEN bit is high. In this case, the LVF interrupt request flag will be set,
causing an interrupt to be generated if VDD falls below the preset LVD voltage. This will cause the
device to wake-up from the SLEEP or IDLE Mode, however if the Low Voltage Detector wake up
function is not required then the LVF flag should be first set high before the device enters the SLEEP
or IDLE Mode.
When LVD function is enabled, it is recommenced to clear LVD flag first, and then enables interrupt
function to avoid mistake action.
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Body Fat Scale 8-Bit Flash MCU
LCD Driver
For large volume applications, which incorporate an LCD in their design, the use of a custom
display rather than a more expensive character based display reduces costs significantly. However,
the corresponding COM and SEG signals required, which vary in both amplitude and time, to drive
such a custom display require many special considerations for proper LCD operation to occur. The
device contains an LCD Driver function, with their internal LCD signal generating circuitry and
various options, will automatically generate these time and amplitude varying signals to provide a
means of direct driving and easy interfacing to a range of custom LCDs.
This device includes a wide range of options to enable LCD displays of various types to be driven.
The table shows the range of options available across the device range.
Driver No.
Duty
Bias
Bias Type
Wave Type
36×4
1/4
1/3
C2
A or B
LCD Selections
VMAX
VDD or V1
PLCD
VIN
C1
0.1μF
C2
V1
VA = V1 = 3/2
VIN
Charge
Pump
0.1μF
VB = PLCD = VIN
VC = V2 = 1/2
VIN
V2
0.1μF
Power Supply from pin PLCD
VMAX
VDD or V1
PLCD
V1
Charge
Pump
VA = V1 = VIN
VB = PLCD = 2/3
VC = V2 = 1/3
0.1μF
C1
0.1μF
C2
0.1μF
V1
VIN
VA = V1 = 3
VIN
VIN
VDD or V1
PLCD
0.1μF
C1
C2
VMAX
Charge
Pump
VIN
VB = PLCD = 2
VIN
VC = V2 = VIN
V2
0.1μF
0.1μF
V2
VIN
Power Supply from pin V2
Power Supply from pin V1
LCD Power Source from External Pin for C2 Type
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Body Fat Scale 8-Bit Flash MCU
VMAX
VDD or V1
PLCD
0.1μF
C1
C2
VDD
VIN
VA = V1 = VIN
V1
Charge
Pump
VB = PLCD = 2/3
VIN
VC = V2 = 1/3
VIN
0.1μF
0.1μF
V2
0.1μF
Power Supply from VA
VMAX
VDD or V1
PLCD
0.1μF
C1
C2
VA = V1 = 3/2
VIN
V1
Charge
Pump
VDD=3.3~5.5V
Regulator
3V
VIN
0.1μF
0.1μF
VB = PLCD = VIN
VC = V2 = 1/2
VIN
V2
0.1μF
Power Supply from VB
VMAX
VDD or V1
PLCD
0.1μF
C1
C2
VA = V1 = 3
VIN
V1
Charge
Pump
VB = PLCD = 2
DPN
VREF
VIN
0.1μF
0.1μF
VIN
VC = V2 = VIN
V2
0.1μF
Power Supply from VC
LCD Power Source from Internal Power for C2 type
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Body Fat Scale 8-Bit Flash MCU
LCD Display Memory
An area of Data Memory is especially reserved for use for the LCD display data. This data area
is known as the LCD Memory. Any data written here will be automatically read by the internal
display driver circuits, which will in turn automatically generate the necessary LCD driving signals.
Therefore any data written into this Memory will be immediately reflected into the actual display
connected to the microcontroller.
The device provides an area of embedded data memory for the LCD display. This area is located
at 80H to A3H in Sector 1 of the Data Memory. To access the Display Memory therefore requires
first that Sector 1 is selected by writing a value of 01H to MP1H or MP2H. After this, the memory
can then be accessed by using indirect addressing through the use of MP1L or MP2L. With Sector 1
selected, then using MP1L/MP2L to read or write to the memory area, from 80H to A3H, will result
in operations to the LCD memory. Directly addressing the Display Memory is not applicable and
will result in a data access to the Sector 0 General Purpose Data Memory.
The LCD display memory can be read and written to only by indirect addressing mode using MP1L/
MP1H and MP2L/MP2H. When data is written into the display data area, it is automatically read
by the LCD driver which then generates the corresponding LCD driving signals. To turn the display
on or off, a "1" or a "0" is written to the corresponding bit of the display memory, respectively. The
figure illustrates the mapping between the display memory and LCD pattern for the device.
b3
b2
b1
b0
A2H
SEG34
A3H
SEG35
COM0
SEG1
COM1
81H
COM2
SEG0
COM3
80H
LCD Memory Map
Clock Source
The LCD clock source is the internal clock signal, fSUB, divided by 8, using an internal divider
circuit. The fSUB internal clock is supplied by either the LIRC or LXT oscillator, the choice of which
is determined by a configuration option. For proper LCD operation, this arrangement is provided to
generate an ideal LCD clock source frequency of 4kHz.
fSUB Clock Source
LCD Clock Frequency
LIRC
4kHz
LXT
4kHz
LCD Clock Source
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Body Fat Scale 8-Bit Flash MCU
LCD Registers
Control Registers in the Data Memory, are used to control the various setup features of the LCD
Driver. There are four control registers for the LCD function, LCDC, LCD1, LCD2 and LCD3.
Various bits in the LCDC register control functions such as waveform type, power source selection
and overall LCD enable/disable. The ENLCD bit in the LCDC register, which provides the overall
LCD enable/disable function, will only be effective when the device is in the Normal, Slow or Idle
Mode. If the device is in the Sleep Mode then the display will always be disabled. Bits LCDP1 and
LCDP0 in the LCDC register are used to select the power source to supply the LCD panel with the
correct bias voltages. A choice to best match the LCD panel used in the application can be selected
also to minimise bias current. The TYPE bit in the same register is used to select whether Type A or
Type B LCD control signals are used.
Three registers, LCD1~LCD3, are used to determine if the output function of display pins
SEG0~SEG23 are used as segment drivers or I/O functions.
LCDC Register
Bit
7
6
5
4
3
2
1
0
Name
TYPE
—
LCDP1
LCDP0
—
—
—
ENLCD
R/W
R/W
—
R/W
R/W
—
—
—
R/W
POR
0
—
0
0
—
—
—
0
Bit 7TYPE: LCD Waveform Type Control
0: Type A
1: Type B
Bit 6
Unimplemented, read as "0"
Bit 5~4LCDP1~LCDP0: LCD power source select for C2 type
00: the power source is from PLCD/V1/V2
01: the power source is from VC = DPN VREF (~1.08V)
10: the power source is from VB = 3V
11: the power source is from VA = VDD
Bit 3~1
Unimplemented, read as "0"
Bit 0ENLCD: LCD Enable Control
0: Disable
1: Enable
LCD1 Register
Bit
7
6
5
4
3
2
1
0
Name
LCDS7
LCDS6
LCDS5
LCDS4
LCDS3
LCDS2
LCDS1
LCDS0
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 7LCDS7: SEG7 Output Control
0: Disable
1: Enable
Bit 6LCDS6: SEG6 Output Control
0: Disable
1: Enable
Bit 5LCDS5: SEG5 Output Control
0: Disable
1: Enable
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Body Fat Scale 8-Bit Flash MCU
Bit 4LCDS4: SEG4 Output Control
0: Disable
1: Enable
Bit 3LCDS3: SEG3 Output Control
0: Disable
1: Enable
Bit 2LCDS2: SEG2 Output Control
0: Disable
1: Enable
Bit 1LCDS1: SEG1 Output Control
0: Disable
1: Enable
Bit 0LCDS0: SEG0 Output Control
0: Disable
1: Enable
LCD2 Register
Bit
7
6
5
4
3
2
1
0
Name
LCDS15
LCDS14
LCDS13
LCDS12
LCDS11
LCDS10
LCDS9
LCDS8
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 7LCDS15: SEG15 Output Control
0: Disable
1: Enable
Bit 6LCDS14: SEG14 Output Control
0: Disable
1: Enable
Bit 5LCDS13: SEG13 Output Control
0: Disable
1: Enable
Bit 4LCDS12: SEG12 Output Control
0: Disable
1: Enable
Bit 3LCDS11: SEG11 Output Control
0: Disable
1: Enable
Bit 2LCDS10: SEG10 Output Control
0: Disable
1: Enable
Bit 1LCDS9: SEG9 Output Control
0: Disable
1: Enable
Bit 0LCDS8: SEG8 Output Control
0: Disable
1: Enable
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Body Fat Scale 8-Bit Flash MCU
LCD3 Register
Bit
7
6
5
4
3
2
1
0
Name
LCDS23
LCDS22
LCDS21
LCDS20
LCDS19
LCDS18
LCDS17
LCDS16
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 7LCDS23: SEG23 Output Control
0: Disable
1: Enable
Bit 6LCDS22: SEG22 Output Control
0: Disable
1: Enable
Bit 5LCDS21: SEG21 Output Control
0: Disable
1: Enable
Bit 4LCDS20: SEG20 Output Control
0: Disable
1: Enable
Bit 3LCDS19: SEG19 Output Control
0: Disable
1: Enable
Bit 2LCDS18: SEG18 Output Control
0: Disable
1: Enable
Bit 1LCDS17: SEG17 Output Control
0: Disable
1: Enable
Bit 0LCDS16: SEG16 Output Control
0: Disable
1: Enable
LCD Driver Output
The output structure of the device LCD driver can be 36×4. The bias type LCD driver is C2 type
only. The LCD driver bias voltage can be 1/3 bias only.
The nature of Liquid Crystal Displays require that only AC voltages can be applied to their pixels
as the application of DC voltages to LCD pixels may cause permanent damage. For this reason the
relative contrast of an LCD display is controlled by the actual RMS voltage applied to each pixel,
which is equal to the RMS value of the voltage on the COM pin minus the voltage applied to the
SEG pin. This differential RMS voltage must be greater than the LCD saturation voltage for the
pixel to be on and less than the threshold voltage for the pixel to be off.
The requirement to limit the DC voltage to zero and to control as many pixels as possible with
a minimum number of connections requires that both a time and amplitude signal is generated
and applied to the application LCD. These time and amplitude varying signals are automatically
generated by the LCD driver circuits in the microcontroller. What is known as the duty determines
the number of common lines used, which are also known as backplanes or COMs. The duty is 1/4
and equates to a COM number of 4, therefore defines the number of time divisions within each
LCD signal frame. Two types of signal generation are also provided, known as Type A and Type B,
the required type is selected via the TYPE bit in the LCDC register. Type B offers lower frequency
signals, however lower frequencies may introduce flickering and influence display clarity.
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Body Fat Scale 8-Bit Flash MCU
LCD Voltage Source and Biasing
The device can have either external pin or internal power source selected via by register bits
LCDP1~LCDP0, LCD voltage source is supplied on external pin PLCD, V1, V2 (LCDP[1:0]=00) or
internal power (LCDP[1:0]=01, 10 or 11) to generate the internal biasing voltages.
When power source is from pin PLCD, The C2 type biasing scheme uses an internal charge pump
circuit, which can generate voltages higher than what is supplied on PLCD. This feature is useful
in applications where the microcontroller supply voltage is less than the supply voltage required by
the LCD. An additional charge pump capacitor must also be connected between pins C1 and C2 to
generate the necessary voltage levels.
Four voltage levels VSS, VA, VB and VC are utilized.
The device has an integrated depletion circuit for LCD voltage source. This could be the DPN VREF
(~1.08V), a fixed 3V voltage generated by an additional regulator or internal power VDD to generate
biasing voltage when bits LCDP1~LCDP0 are configured 01, 10 or 11.
When power source is from pin V1 or VDD, which is maximum bias. The pin PLCD must connect
a 0.1µF to ground. The voltage VA will have a value equal to V1 or VDD, and charge pump will
generate VB and VC, VB will have a value equal to VA × 2/3 and VC will have a value equal to VA
× 1/3.
When power source is from pin PLCD or internal regulator output, the voltage VA is generated
internally and has a value of VB × 3/2. VB will have a value equal to PLCD or 3V, and VC will have
a value equal to VB × 1/2.
When power source is from pin V2 or DPN VREF, The voltage VA is generated internally and has
a value of VC × 3. VB will have a value equal to VC × 2 and VC will have a value equal to V2 or
DPN VREF.
The connection to the VMAX pin depends upon the bias and the voltage that is applied to PLCD, the
details are shown in the table. It is extremely important to ensure that these charge pump generated
internal voltages do not exceed the maximum VDD voltage of 5.5V.
Biasing Type
1/3 Bias
Rev. 1.10
VMAX Connection
VDD > PLCD × 1.5
Connect VMAX to VDD
Otherwise
Connect VMAX to V1
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Body Fat Scale 8-Bit Flash MCU
LCD Waveform Timing Diagrams
The device generates 1/4 duty and 1 /3 bias LCD signals, as shown below.
During
LCD
Off Reset or LCD Off
COM0, COM1, COM2, COM3
All segment outputs
1 Frame
Normal Operation Mode
VA
VB
VC
VSS
VA
VB
VC
VSS
VA
VB
VC
VSS
COM0
VA
VB
VC
VSS
VA
VB
VC
VSS
COM1
COM2
VA
VB
VC
VSS
COM3
VA
VB
VC
VSS
VA
VB
VC
VSS
VA
VB
VC
VSS
VA
VB
VC
VSS
VA
VB
VC
VSS
VA
VB
VC
VSS
All segments OFF
COM0 segments ON
COM1 segments ON
COM2 segments ON
COM3 segments ON
COM0, 1 segments ON
VA
VB
VC
VSS
VA
VB
VC
VSS
COM0, 2 segments ON
COM0, 3 segments ON
(other combinations are omitted)
All segments ON
VA
VB
VC
VSS
LCD Driver Output – Type A - 1/4 Duty, 1/3 Bias
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Body Fat Scale 8-Bit Flash MCU
LCD Off Mode
VA
VB
VC
VSS
VA
VB
VC
VSS
COM0,COM1,COM2,COM3
All sengment outputs
Normal Operation Mode
1 Frame
VA
VB
VC
VSS
VA
VB
VC
VSS
VA
VB
VC
VSS
VA
VB
VC
VSS
VA
VB
VC
VSS
VA
VB
VC
VSS
VA
VB
VC
VSS
VA
VB
VC
VSS
VA
VB
VC
VSS
VA
VB
VC
VSS
VA
VB
VC
VSS
VA
VB
VC
VSS
COM0
COM1
COM2
COM3
All segments are OFF
COM0 side segments are ON
COM1 side segments are ON
COM2 side segments are ON
COM3 side segments are ON
COM0,1 side segments are ON
COM0,2 side segments are ON
COM0,3 side segments are ON
(other combinations are omitted)
VA
VB
VC
VSS
All sengments are ON
LCD Driver Output – Type B - 1/4 Duty, 1/3 Bias
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Programming Considerations
Certain precautions must be taken when programming the LCD. One of these is to ensure that
the LCD Memory is properly initialised after the microcontroller is powered on. Like the General
Purpose Data Memory, the contents of the LCD Memory are in an unknown condition after poweron. As the contents of the LCD Memory will be mapped into the actual display, it is important to
initialise this memory area into a known condition soon after applying power to obtain a proper
display pattern.
Consideration must also be given to the capacitive load of the actual LCD used in the application.
As the load presented to the microcontroller by LCD pixels can be generally modeled as mainly
capacitive in nature, it is important that this is not excessive, a point that is particularly true in the
case of the COM lines which may be connected to many LCD pixels. The accompanying diagram
depicts the equivalent circuit of the LCD.
One additional consideration that must be taken into account is what happens when the
microcontroller enters the Idle or Slow Mode. The ENLCD control bit in the LCDC register permits
the display to be powered off to reduce power consumption. If this bit is zero, the driving signals
to the display will cease, producing a blank display pattern but reducing any power consumption
associated with the LCD.
After Power-on, note that as the ENLCD bit will be cleared to zero, the display function will be
disabled.
LCD Panel Equivalent Circuit
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Body Fat Scale 8-Bit Flash MCU
Body Fat Measurement Function
The body fat circuit consists of a sine wave generator, an amplifier and a filter. The circuit has been
designed for maximum flexibility and has a high degree of functional integration to implement a
body fat measurement function. The circuit is powered by the LDO.
Sine Wave Generator
The sine wave generator consists of a frequency divider, counter, RAM, 10-bit DAC and OP0.
The circuit can generate a sine wave output with a frequency range of 5kHz ~ 200kHz using a
32×9 bit RAM for the sine wave pattern simulation. The frequency divider will multiply by DN/
M to generate a clock for the counter. The following points must be noted to understand how the
sine wave is generated:
• System clock/M = sine wave frequency
• System clock × (DN/M) = the count rate of the counter
• M must be a multiple of N and 8
• M = N×DN
• DNR = DN/2
• DN: sine wave cycle data numerical value (DN ≤ 64)
• DNR: the data numerical value of the 1/2 sine wave cycle stored in RAM (DNR ≤ 32)
Refer to the following table and figure for more details.
System
Frequency
4.8MHz
9.6MHz
14.4MHz
The frequency of
sine wave(kHz)
200
100
50
5
200
100
50
5
M
24
48
96
960
48
96
192
N
1
1
2
20
1
2
DN
24
48
48
48
48
DNR
12
24
24
24
24
200 100
50
5
1920
72
144
288
2880
4
40
2
4
8
48
48
48
48
36
36
36
60
24
24
24
18
18
18
30
�11
0
P0 P�
P1
PDNR-3PDNR-1
PDNR-�
-�1�
Rev. 1.10
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Body Fat Scale 8-Bit Flash MCU
Only a half sine wave pattern P0~PDNR-1 is generated which is stored in RAM Sector 2 with an
address range of 80H~BFH. The sine wave pattern data bits [7:0] are stored with even addresses
while the sine wave pattern data bit [8] is stored with an odd address. Once the sine wave generator
is enabled, the CPU will not be able to write or read data to/from this RAM area. The sine generator
will read the RAM data and transmit it to the 10-bit DAC.
The device will read the half sine wave pattern from the RAM and generate the actual sine waveform
on the SIN pin. Refer to the following diagram:
DN_CNT>=DNR
“0”
0
“1”
1
D[�]
SINE[8:0]
0
�'s
Complement
80H
SINE1[7:0]
SINE1[8]
SINE0[8:0]
SINE1[8:0]
SINE�[8:0]
SINE3[8:0]
.
.
.
.
.
SINE30[8:0]
SINE31[8:0]
BBH
SINE30[7:0]
SINE30[8]
BDH
SINE31[7:0]
SINE31[8]
BFH
SINE Wave Pattern
RAM (Sector 2)
Rev. 1.10
DAC
SINE0[8]
.
.
.
BEH
D[�:0]
SINE0[7:0]
83H
BCH
+
1
81H
8�H
D[8:0]
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Body Fat Scale 8-Bit Flash MCU
SGC Register
Bit
7
6
5
4
3
2
1
0
Name
SGEN
—
—
BREN
—
—
—
—
R/W
R/W
—
—
R/W
—
—
—
—
POR
0
—
—
0
—
—
—
—
Bit 7SGEN: sine generator enable bit
0: Disable
1: Enable
When this bit is equal to "0", the OP0 and 10-bit DAC will be in a power down mode.
Bit 6~5
Unimplemented, read as "0"
Bit 4BREN: Bias resistor enable bit
0: Disable - power down mode
1: Enable - normal mode
When this bit is enabled, it will generate a 0.5 × AVDD voltage for the non-inverting
input of OPA1 and OPA2.
Bit 3~0
Unimplemented, read as "0"
SGN Register
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
—
—
0
0
0
0
0
0
2
1
0
Bit 7~6
Unimplemented, read as "0"
Bit 5~0D5~D0: Sine Generator Data
System frequency multiplicator, N, is equal to D[5:0] + 1.
SGDNR Register
Bit
7
6
5
Name
—
—
—
D4
D3
D2
D1
D0
R/W
—
—
—
R/W
R/W
R/W
R/W
R/W
POR
—
—
—
0
0
0
0
0
Bit 7~5
4
3
Unimplemented, read as "0"
Bit 4~0D4~D0: Data Number of Sample
1/2 sine wave cycle numerical value is stored in RAM Sector 2. DNR is equal to
D[4:0] + 1.
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Amplifier
The amplifier consists of OP1, OP2, a 6-bit DAC and analog switches. OP2 is a differential amplifier
with 1~5 multiple gain. The 6-bit DAC offers a reference voltage to the non-inverting input of OP2. The
user can turn on and off switch 0 to 7 to obtain a reference resistor voltage and a body resistor voltage.
The body and reference impedance can be obtained by using the SW0 ~ SW7 switches. Refer to
following table for this impedance switching.
Switch
SW0
Foot Impedance
O
SW1
Reference 1kΩ
O
Reference 200Ω
O
SW2
SW3
SW4
SW5
O
O
SW6
SW7
O
O
O
O
O: Switch is on
OPAC Register
Bit
7
6
5
4
3
2
1
0
Name
OPAEN
—
R/W
R/W
—
—
—
OP2G3
OP2G2
OP2G1
OP2G0
—
—
R/W
R/W
R/W
R/W
POR
0
—
—
—
0
0
0
0
Bit 7OPAEN: OP Amplifier control bit
0: Disable
1: Enable
When this bit is equal to"0", OP1, OP2 and 6-bit DAC will be in a power down mode.
Bit 6~4
Unimplemented, read as "0"
Bit 3~0OP2G3~OP2G0: OP2 gain control bit
0001: 1.14
0010: 1.31
0011: 1.5
0100: 1.73
0101: 2
0110: 2.33
0111: 2.75
1000: 3.285
1001: 4
1010: 5
Others: 1
SWC Register
Bit
7
6
5
4
3
2
1
0
Name
SW7
SW6
SW5
SW4
SW3
SW2
SW1
SW0
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 SW7: Switch 7 control bit
0: Off
1: On
Bit 6SW6: Switch 6 control bit
0: Off
1: On
Bit 5SW5: Switch 5 control bit
0: Off
1: On
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Bit 4 SW4: Switch 4 control bit
0: Off
1: On
Bit 3SW3: Switch 3 control bit
0: Off
1: On
Bit 2SW2: Switch 2 control bit
0: Off
1: On
Bit 1SW1: Switch 1 control bit
0: Off
1: On
Bit 0SW0: Switch 0 control bit
0: Off
1: On
DACO Register
Bit
7
6
Name
—
—
D5
D4
D3
D2
D1
D0
R/W
—
—
R/W
R/W
R/W
R/W
R/W
R/W
POR
—
—
0
0
0
0
0
0
Bit 7~6
5
4
3
2
1
0
Unimplemented, read as "0"
Bit 5~0D5~D0: 6-bit DAC output voltage
Output voltage = 0.5AVDD × ((D[5:0] + 1) / 64)
Filter
The filter consists of CP0, a PMOS transistor and some analog switches. The filter contains a peak
detection function for which an external capacitor will store the peak value for transmission to the
ADC. Switches SW8 and SW9 are for capacitor discharge purposes.
FTRC Register
Bit
7
6
5
4
3
2
1
0
Name
FTREN
—
—
HYSEN
—
—
SW9
SW8
R/W
R/W
—
—
R/W
—
—
R/W
R/W
POR
0
—
—
0
—
—
0
0
Bit 7FTREN: Filter control bit
0: Disable
1: Enable
When this bit is equal to "0", CP0 and PMOS enter power down mode.
Bit 6~5
Unimplemented, read as "0"
Bit 4HYSEN: Reserved
Bit 3~2
Unimplemented, read as "0"
Bit 1SW9: Switch 9 control bit
0: Off
1: On
Bit 0SW8: Switch 8 control bit
0: Off
1: On
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Configuration Option
Configuration options refer to certain options within the MCU that are programmed into the device
during the programming process. During the development process, these options are selected using
the HT-IDE software development tools. As these options are programmed into the device using
the hardware programming tools, once they are selected they cannot be changed later using the
application program. All options must be defined for proper system function, the details of which are
shown in the table.
No.
Options
Oscillator Options
1
High Speed System Oscillator Selection – fH:
1. HXT
2. HIRC
2
HIRC Frequency Selection:
1. 4.8MHz
2. 9.6MHz
3. 14.4MHz
3
Low Speed System Oscillator Selection – fSUB:
1. LXT
2. LIRC
Watchdog Timer Options
Rev. 1.10
4
WDT function:
1. Always enable
2. Controlled by WDT Control Register
5
WDT Clock Selection – fS:
1. fSUB
2. fSYS/4
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Application Circuit
VDD
VDD
VDD
VIN
PB4/XT2
AVDD
0.1µF
10μF
PB3/XT1
VSS
AVDD
PB1/OSC1
0.1µF
PB2/OSC2
AVSS
PB0
PA0/ICPDA/OCDSDA
VCM
1kΩ
1kΩ
1kΩ
1kΩ
0.1µF
0.1µF
PA2/ICPCK/OCDSCK
VREFP
PA1/TP2_1/INT1
VREFN
PA3/TP2_0/INT0
PA4/TCK2
AN0
VDD
150kΩ
(BAT Detect)
PA5/TP1_1/SCK/SCL
AN1
PA6/TP1_0/SCS
AN2
200kΩ
AN3
PA7/TCK1/SDO/SEG0
AVDD
PC1/TP0_1/SDI/SDA/SEG1
PC2/TP0_0/RX/SEG2
PC3/TCK0/TX/SEG3
51kΩ
100kΩ
0.1µF
PC4/SEG4
HT45F77
0.1µF
PC5/SEG5
PC6/SEG6
PC7/SEG7
33kΩ
PD0/SEG8
RFC
CP0N
TO
PE7/SEG23
SEG24
FVR
1kΩ
200Ω
33kΩ
LCD
4 x 36
SEG35
33kΩ
COM3
COM0
FIR
V2
V1
2.7kΩ
0.1µF
C2
RF2
0.1µF
C1
RF1
PLCD
FIL
VMAX
FVL
0.1µF 0.1µF 0.1µF
SIN
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Instruction Set
Introduction
Central to the successful operation of any microcontroller is its instruction set, which is a set of
program instruction codes that directs the microcontroller to perform certain operations. In the case
of Holtek microcontroller, a comprehensive and flexible set of over 60 instructions is provided to
enable programmers to implement their application with the minimum of programming overheads.
For easier understanding of the various instruction codes, they have been subdivided into several
functional groupings.
Instruction Timing
Most instructions are implemented within one instruction cycle. The exceptions to this are branch,
call, or table read instructions where two instruction cycles are required. One instruction cycle is
equal to 4 system clock cycles, therefore in the case of an 8MHz system oscillator, most instructions
would be implemented within 0.5μs and branch or call instructions would be implemented within
1μs. Although instructions which require one more cycle to implement are generally limited to
the JMP, CALL, RET, RETI and table read instructions, it is important to realize that any other
instructions which involve manipulation of the Program Counter Low register or PCL will also take
one more cycle to implement. As instructions which change the contents of the PCL will imply a
direct jump to that new address, one more cycle will be required. Examples of such instructions
would be "CLR PCL" or "MOV PCL, A". For the case of skip instructions, it must be noted that if
the result of the comparison involves a skip operation then this will also take one more cycle, if no
skip is involved then only one cycle is required.
Moving and Transferring Data
The transfer of data within the microcontroller program is one of the most frequently used
operations. Making use of three kinds of MOV instructions, data can be transferred from registers to
the Accumulator and vice-versa as well as being able to move specific immediate data directly into
the Accumulator. One of the most important data transfer applications is to receive data from the
input ports and transfer data to the output ports.
Arithmetic Operations
The ability to perform certain arithmetic operations and data manipulation is a necessary feature of
most microcontroller applications. Within the Holtek microcontroller instruction set are a range of
add and subtract instruction mnemonics to enable the necessary arithmetic to be carried out. Care
must be taken to ensure correct handling of carry and borrow data when results exceed 255 for
addition and less than 0 for subtraction. The increment and decrement instructions INC, INCA, DEC
and DECA provide a simple means of increasing or decreasing by a value of one of the values in the
destination specified.
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Logical and Rotate Operation
The standard logical operations such as AND, OR, XOR and CPL all have their own instruction
within the Holtek microcontroller instruction set. As with the case of most instructions involving
data manipulation, data must pass through the Accumulator which may involve additional
programming steps. In all logical data operations, the zero flag may be set if the result of the
operation is zero. Another form of logical data manipulation comes from the rotate instructions such
as RR, RL, RRC and RLC which provide a simple means of rotating one bit right or left. Different
rotate instructions exist depending on program requirements. Rotate instructions are useful for serial
port programming applications where data can be rotated from an internal register into the Carry
bit from where it can be examined and the necessary serial bit set high or low. Another application
which rotate data operations are used is to implement multiplication and division calculations.
Branches and Control Transfer
Program branching takes the form of either jumps to specified locations using the JMP instruction
or to a subroutine using the CALL instruction. They differ in the sense that in the case of a
subroutine call, the program must return to the instruction immediately when the subroutine has
been carried out. This is done by placing a return instruction "RET" in the subroutine which will
cause the program to jump back to the address right after the CALL instruction. In the case of a JMP
instruction, the program simply jumps to the desired location. There is no requirement to jump back
to the original jumping off point as in the case of the CALL instruction. One special and extremely
useful set of branch instructions are the conditional branches. Here a decision is first made regarding
the condition of a certain data memory or individual bits. Depending upon the conditions, the
program will continue with the next instruction or skip over it and jump to the following instruction.
These instructions are the key to decision making and branching within the program perhaps
determined by the condition of certain input switches or by the condition of internal data bits.
Bit Operations
The ability to provide single bit operations on Data Memory is an extremely flexible feature of all
Holtek microcontrollers. This feature is especially useful for output port bit programming where
individual bits or port pins can be directly set high or low using either the "SET [m].i" or "CLR [m].
i" instructions respectively. The feature removes the need for programmers to first read the 8-bit
output port, manipulate the input data to ensure that other bits are not changed and then output the
port with the correct new data. This read-modify-write process is taken care of automatically when
these bit operation instructions are used.
Table Read Operations
Data storage is normally implemented by using registers. However, when working with large
amounts of fixed data, the volume involved often makes it inconvenient to store the fixed data in
the Data Memory. To overcome this problem, Holtek microcontrollers allow an area of Program
Memory to be set as a table where data can be directly stored. A set of easy to use instructions
provides the means by which this fixed data can be referenced and retrieved from the Program
Memory.
Other Operations
In addition to the above functional instructions, a range of other instructions also exist such as
the "HALT" instruction for Power-down operations and instructions to control the operation of
the Watchdog Timer for reliable program operations under extreme electric or electromagnetic
environments. For their relevant operations, refer to the functional related sections.
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Instruction Set Summary
The instructions related to the data memory access in the following table can be used when the
desired data memory is located in Data Memory sector 0.
Table Conventions
x: Bits immediate data
m: Data Memory address
A: Accumulator
i: 0~7 number of bits
addr: Program memory address
Mnemonic
Description
Cycles
Flag Affected
Add Data Memory to ACC
Add ACC to Data Memory
Add immediate data to ACC
Add Data Memory to ACC with Carry
Add ACC to Data memory with Carry
Subtract immediate data from the ACC
Subtract Data Memory from ACC
Subtract Data Memory from ACC with result in Data Memory
Subtract immediate data from ACC with Carry
Subtract Data Memory from ACC with Carry
Subtract Data Memory from ACC with Carry, result in Data Memory
Decimal adjust ACC for Addition with result in Data Memory
1
1Note
1
1
1Note
1
1
1Note
1
1
1Note
1Note
Z, C, AC, OV, SC
Z, C, AC, OV, SC
Z, C, AC, OV, SC
Z, C, AC, OV, SC
Z, C, AC, OV, SC
Z, C, AC, OV, SC, CZ
Z, C, AC, OV, SC, CZ
Z, C, AC, OV, SC, CZ
Z, C, AC, OV, SC, CZ
Z, C, AC, OV, SC, CZ
Z, C, AC, OV, SC, CZ
C
1
1
1
1Note
1Note
1Note
1
1
1
1Note
1
Z
Z
Z
Z
Z
Z
Z
Z
Z
Z
Z
Increment Data Memory with result in ACC
Increment Data Memory
Decrement Data Memory with result in ACC
Decrement Data Memory
1
1Note
1
1Note
Z
Z
Z
Z
Rotate Data Memory right with result in ACC
Rotate Data Memory right
Rotate Data Memory right through Carry with result in ACC
Rotate Data Memory right through Carry
Rotate Data Memory left with result in ACC
Rotate Data Memory left
Rotate Data Memory left through Carry with result in ACC
Rotate Data Memory left through Carry
1
1Note
1
1Note
1
1Note
1
1Note
None
None
C
C
None
None
C
C
Arithmetic
ADD A,[m]
ADDM A,[m]
ADD A,x
ADC A,[m]
ADCM A,[m]
SUB A,x
SUB A,[m]
SUBM A,[m]
SBC A,x
SBC A,[m]
SBCM A,[m]
DAA [m]
Logic Operation
AND A,[m]
OR A,[m]
XOR A,[m]
ANDM A,[m]
ORM A,[m]
XORM A,[m]
AND A,x
OR A,x
XOR A,x
CPL [m]
CPLA [m]
Logical AND Data Memory to ACC
Logical OR Data Memory to ACC
Logical XOR Data Memory to ACC
Logical AND ACC to Data Memory
Logical OR ACC to Data Memory
Logical XOR ACC to Data Memory
Logical AND immediate Data to ACC
Logical OR immediate Data to ACC
Logical XOR immediate Data to ACC
Complement Data Memory
Complement Data Memory with result in ACC
Increment & Decrement
INCA [m]
INC [m]
DECA [m]
DEC [m]
Rotate
RRA [m]
RR [m]
RRCA [m]
RRC [m]
RLA [m]
RL [m]
RLCA [m]
RLC [m]
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Mnemonic
Description
Cycles Flag Affected
Data Move
MOV A,[m]
MOV [m],A
MOV A,x
Move Data Memory to ACC
Move ACC to Data Memory
Move immediate data to ACC
1
1Note
1
None
None
None
Clear bit of Data Memory
Set bit of Data Memory
1Note
1Note
None
None
2
1Note
1Note
1Note
1Note
1Note
1Note
1Note
1Note
1Note
2
2
2
2
None
None
None
None
None
None
None
None
None
None
None
None
None
None
2Note
2Note
2Note
None
None
None
2Note
None
1
1Note
1Note
1
1Note
1
1
None
None
None
TO, PDF
None
None
TO, PDF
Bit Operation
CLR [m].i
SET [m].i
Branch Operation
JMP addr
SZ [m]
SZA [m]
SZ [m].i
SNZ [m]
SNZ [m].i
SIZ [m]
SDZ [m]
SIZA [m]
SDZA [m]
CALL addr
RET
RET A,x
RETI
Jump unconditionally
Skip if Data Memory is zero
Skip if Data Memory is zero with data movement to ACC
Skip if bit i of Data Memory is zero
Skip if Data Memory is not zero
Skip if bit i of Data Memory is not zero
Skip if increment Data Memory is zero
Skip if decrement Data Memory is zero
Skip if increment Data Memory is zero with result in ACC
Skip if decrement Data Memory is zero with result in ACC
Subroutine call
Return from subroutine
Return from subroutine and load immediate data to ACC
Return from interrupt
Table Read Operation
TABRD [m] Read table to TBLH and Data Memory
TABRDL [m] Read table (last page) to TBLH and Data Memory
ITABRD [m] Increment table pointer TBLP first and Read table to TBLH and Data Memory
Increment table pointer TBLP first and Read table (last page) to TBLH and
ITABRDL [m]
Data Memory
Miscellaneous
NOP
CLR [m]
SET [m]
CLR WDT
SWAP [m]
SWAPA [m]
HALT
No operation
Clear Data Memory
Set Data Memory
Clear Watchdog Timer
Swap nibbles of Data Memory
Swap nibbles of Data Memory with result in ACC
Enter power down mode
Note: 1. For skip instructions, if the result of the comparison involves a skip then up to three cycles are required, if
no skip takes place only one cycle is required.
2. Any instruction which changes the contents of the PCL will also require 2 cycles for execution.
3. For the “CLR WDT” instruction the TO and PDF flags may be affected by the execution status. The TO
and PDF flags are cleared after the “CLR WDT” instructions is executed. Otherwise the TO and PDF
flags remain unchanged.
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Extended Instruction Set
The extended instructions are used to support the full range address access for the data memory.
When the accessed data memory is located in any data memory sector except sector 0, the extended
instruction can be used to access the data memory instead of using the indirect addressing access to
improve the CPU firmware performance.
Mnemonic
Description
Cycles
Flag Affected
Add Data Memory to ACC
Add ACC to Data Memory
Add Data Memory to ACC with Carry
Add ACC to Data memory with Carry
Subtract Data Memory from ACC
Subtract Data Memory from ACC with result in Data Memory
Subtract Data Memory from ACC with Carry
Subtract Data Memory from ACC with Carry, result in Data Memory
Decimal adjust ACC for Addition with result in Data Memory
2
2Note
2
2Note
2
2Note
2
2Note
2Note
Z, C, AC, OV, SC
Z, C, AC, OV, SC
Z, C, AC, OV, SC
Z, C, AC, OV, SC
Z, C, AC, OV, SC, CZ
Z, C, AC, OV, SC, CZ
Z, C, AC, OV, SC, CZ
Z, C, AC, OV, SC, CZ
C
2
2
2
2Note
2Note
2Note
2Note
2
Z
Z
Z
Z
Z
Z
Z
Z
Increment Data Memory with result in ACC
Increment Data Memory
Decrement Data Memory with result in ACC
Decrement Data Memory
2
2Note
2
2Note
Z
Z
Z
Z
Rotate Data Memory right with result in ACC
Rotate Data Memory right
Rotate Data Memory right through Carry with result in ACC
Rotate Data Memory right through Carry
Rotate Data Memory left with result in ACC
Rotate Data Memory left
Rotate Data Memory left through Carry with result in ACC
Rotate Data Memory left through Carry
2
2Note
2
2Note
2
2Note
2
2Note
None
None
C
C
None
None
C
C
Move Data Memory to ACC
Move ACC to Data Memory
2
2Note
None
None
Clear bit of Data Memory
Set bit of Data Memory
2Note
2Note
None
None
Arithmetic
LADD A,[m]
LADDM A,[m]
LADC A,[m]
LADCM A,[m]
LSUB A,[m]
LSUBM A,[m]
LSBC A,[m]
LSBCM A,[m]
LDAA [m]
Logic Operation
LAND A,[m]
LOR A,[m]
LXOR A,[m]
LANDM A,[m]
LORM A,[m]
LXORM A,[m]
LCPL [m]
LCPLA [m]
Logical AND Data Memory to ACC
Logical OR Data Memory to ACC
Logical XOR Data Memory to ACC
Logical AND ACC to Data Memory
Logical OR ACC to Data Memory
Logical XOR ACC to Data Memory
Complement Data Memory
Complement Data Memory with result in ACC
Increment & Decrement
LINCA [m]
LINC [m]
LDECA [m]
LDEC [m]
Rotate
LRRA [m]
LRR [m]
LRRCA [m]
LRRC [m]
LRLA [m]
LRL [m]
LRLCA [m]
LRLC [m]
Data Move
LMOV A,[m]
LMOV [m],A
Bit Operation
LCLR [m].i
LSET [m].i
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Mnemonic
Description
Cycles Flag Affected
Branch
LSZ [m]
LSZA [m]
LSNZ [m]
LSZ [m].i
LSNZ [m].i
LSIZ [m]
LSDZ [m]
LSIZA [m]
LSDZA [m]
Skip if Data Memory is zero
Skip if Data Memory is zero with data movement to ACC
Skip if Data Memory is not zero
Skip if bit i of Data Memory is zero
Skip if bit i of Data Memory is not zero
Skip if increment Data Memory is zero
Skip if decrement Data Memory is zero
Skip if increment Data Memory is zero with result in ACC
Skip if decrement Data Memory is zero with result in ACC
2Note
2Note
2Note
2Note
2Note
2Note
2Note
2Note
2Note
None
None
None
None
None
None
None
None
None
3Note
3Note
3Note
None
None
None
3Note
None
2Note
2Note
2Note
2
None
None
None
None
Table Read
LTABRD [m] Read table to TBLH and Data Memory
LTABRDL [m] Read table (last page) to TBLH and Data Memory
LITABRD [m] Increment table pointer TBLP first and Read table to TBLH and Data Memory
Increment table pointer TBLP first and Read table (last page) to TBLH and
LITABRDL [m]
Data Memory
Miscellaneous
LCLR [m]
LSET [m]
LSWAP [m]
LSWAPA [m]
Clear Data Memory
Set Data Memory
Swap nibbles of Data Memory
Swap nibbles of Data Memory with result in ACC
Note: 1. For these extended skip instructions, if the result of the comparison involves a skip then up to four cycles
are required, if no skip takes place two cycles is required.
2. Any extended instruction which changes the contents of the PCL register will also require three cycles for
execution.
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Instruction Definition
ADC A,[m]
Description
Operation
Affected flag(s)
Add Data Memory to ACC with Carry
The contents of the specified Data Memory, Accumulator and the carry flag are added.
The result is stored in the Accumulator.
ACC ← ACC + [m] + C
OV, Z, AC, C, SC
ADCM A,[m]
Description
Operation
Affected flag(s)
Add ACC to Data Memory with Carry
The contents of the specified Data Memory, Accumulator and the carry flag are added. The result is stored in the specified Data Memory.
[m] ← ACC + [m] + C
OV, Z, AC, C, SC
Add Data Memory to ACC
ADD A,[m]
Description
The contents of the specified Data Memory and the Accumulator are added.
The result is stored in the Accumulator.
Operation
Affected flag(s)
ACC ← ACC + [m]
OV, Z, AC, C, SC
ADD A,x
Description
Operation
Affected flag(s)
Add immediate data to ACC
The contents of the Accumulator and the specified immediate data are added. The result is stored in the Accumulator.
ACC ← ACC + x
OV, Z, AC, C, SC
ADDM A,[m]
Description
Operation
Affected flag(s)
Add ACC to Data Memory
The contents of the specified Data Memory and the Accumulator are added. The result is stored in the specified Data Memory.
[m] ← ACC + [m]
OV, Z, AC, C, SC
AND A,[m]
Description
Operation
Affected flag(s)
Logical AND Data Memory to ACC
Data in the Accumulator and the specified Data Memory perform a bitwise logical AND operation. The result is stored in the Accumulator.
ACC ← ACC ″AND″ [m]
Z
AND A,x
Description
Operation
Affected flag(s)
Logical AND immediate data to ACC
Data in the Accumulator and the specified immediate data perform a bit wise logical AND operation. The result is stored in the Accumulator.
ACC ← ACC ″AND″ x
Z
ANDM A,[m]
Description
Operation
Affected flag(s)
Logical AND ACC to Data Memory
Data in the specified Data Memory and the Accumulator perform a bitwise logical AND
operation. The result is stored in the Data Memory.
[m] ← ACC ″AND″ [m]
Z
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CALL addr
Description
Operation
Affected flag(s)
Subroutine call
Unconditionally calls a subroutine at the specified address. The Program Counter then
increments by 1 to obtain the address of the next instruction which is then pushed onto the
stack. The specified address is then loaded and the program continues execution from this
new address. As this instruction requires an additional operation, it is a two cycle instruction.
Stack ← Program Counter + 1
Program Counter ← addr
None
CLR [m]
Description
Operation
Affected flag(s)
Clear Data Memory
Each bit of the specified Data Memory is cleared to 0.
[m] ← 00H
None
CLR [m].i
Description
Operation
Affected flag(s)
Clear bit of Data Memory
Bit i of the specified Data Memory is cleared to 0.
[m].i ← 0
None
CLR WDT
Description
Operation
Affected flag(s)
Clear Watchdog Timer
The TO, PDF flags and the WDT are all cleared.
WDT cleared
TO ← 0
PDF ← 0
TO, PDF
CPL [m]
Description
Operation
Affected flag(s)
Complement Data Memory
Each bit of the specified Data Memory is logically complemented (1′s complement). Bits which
previously contained a 1 are changed to 0 and vice versa.
[m] ← [m]
Z
CPLA [m]
Description
Operation
Affected flag(s)
Complement Data Memory with result in ACC
Each bit of the specified Data Memory is logically complemented (1′s complement). Bits which
previously contained a 1 are changed to 0 and vice versa. The complemented result is stored in
the Accumulator and the contents of the Data Memory remain unchanged.
ACC ← [m]
Z
DAA [m]
Description
Operation
Affected flag(s)
Decimal-Adjust ACC for addition with result in Data Memory
Convert the contents of the Accumulator value to a BCD (Binary Coded Decimal) value
resulting from the previous addition of two BCD variables. If the low nibble is greater than 9
or if AC flag is set, then a value of 6 will be added to the low nibble. Otherwise the low nibble
remains unchanged. If the high nibble is greater than 9 or if the C flag is set, then a value of 6
will be added to the high nibble. Essentially, the decimal conversion is performed by adding
00H, 06H, 60H or 66H depending on the Accumulator and flag conditions. Only the C flag
may be affected by this instruction which indicates that if the original BCD sum is greater than
100, it allows multiple precision decimal addition.
[m] ← ACC + 00H or
[m] ← ACC + 06H or [m] ← ACC + 60H or
[m] ← ACC + 66H
C
Rev. 1.10
185
January 19, 2015
HT45F77
Body Fat Scale 8-Bit Flash MCU
DEC [m]
Description
Operation
Affected flag(s)
Decrement Data Memory
Data in the specified Data Memory is decremented by 1.
[m] ← [m] − 1
Z
DECA [m]
Description
Operation
Affected flag(s)
Decrement Data Memory with result in ACC
Data in the specified Data Memory is decremented by 1. The result is stored in the
Accumulator. The contents of the Data Memory remain unchanged.
ACC ← [m] − 1
Z
HALT
Description
Operation
Affected flag(s)
Enter power down mode
This instruction stops the program execution and turns off the system clock. The contents of the Data Memory and registers are retained. The WDT and prescaler are cleared. The power
down flag PDF is set and the WDT time-out flag TO is cleared.
TO ← 0
PDF ← 1
TO, PDF
INC [m]
Description
Operation
Affected flag(s)
Increment Data Memory
Data in the specified Data Memory is incremented by 1.
[m] ← [m] + 1
Z
INCA [m]
Description
Operation
Affected flag(s)
Increment Data Memory with result in ACC
Data in the specified Data Memory is incremented by 1. The result is stored in the Accumulator.
The contents of the Data Memory remain unchanged.
ACC ← [m] + 1
Z
JMP addr
Description
Operation
Affected flag(s)
Jump unconditionally
The contents of the Program Counter are replaced with the specified address. Program
execution then continues from this new address. As this requires the insertion of a dummy
instruction while the new address is loaded, it is a two cycle instruction.
Program Counter ← addr
None
MOV A,[m]
Description
Operation
Affected flag(s)
Move Data Memory to ACC
The contents of the specified Data Memory are copied to the Accumulator.
ACC ← [m]
None
MOV A,x
Description
Operation
Affected flag(s)
Move immediate data to ACC
The immediate data specified is loaded into the Accumulator.
ACC ← x
None
MOV [m],A
Description
Operation
Affected flag(s)
Move ACC to Data Memory
The contents of the Accumulator are copied to the specified Data Memory.
[m] ← ACC
None
Rev. 1.10
186
January 19, 2015
HT45F77
Body Fat Scale 8-Bit Flash MCU
NOP
Description
Operation
Affected flag(s)
No operation
No operation is performed. Execution continues with the next instruction.
No operation
None
OR A,[m]
Description
Operation
Affected flag(s)
Logical OR Data Memory to ACC
Data in the Accumulator and the specified Data Memory perform a bitwise
logical OR operation. The result is stored in the Accumulator.
ACC ← ACC ″OR″ [m]
Z
OR A,x
Description
Operation
Affected flag(s)
Logical OR immediate data to ACC
Data in the Accumulator and the specified immediate data perform a bitwise logical OR operation. The result is stored in the Accumulator.
ACC ← ACC ″OR″ x
Z
ORM A,[m]
Description
Operation
Affected flag(s)
Logical OR ACC to Data Memory
Data in the specified Data Memory and the Accumulator perform a bitwise logical OR operation. The result is stored in the Data Memory.
[m] ← ACC ″OR″ [m]
Z
RET
Description
Operation
Affected flag(s)
Return from subroutine
The Program Counter is restored from the stack. Program execution continues at the restored
address.
Program Counter ← Stack
None
RET A,x
Description
Operation
Affected flag(s)
Return from subroutine and load immediate data to ACC
The Program Counter is restored from the stack and the Accumulator loaded with the specified immediate data. Program execution continues at the restored address.
Program Counter ← Stack
ACC ← x
None
RETI
Description
Operation
Affected flag(s)
Return from interrupt
The Program Counter is restored from the stack and the interrupts are re-enabled by setting the
EMI bit. EMI is the master interrupt global enable bit. If an interrupt was pending when the RETI instruction is executed, the pending Interrupt routine will be processed before returning to the main program.
Program Counter ← Stack
EMI ← 1
None
RL [m]
Description
Operation
Affected flag(s)
Rotate Data Memory left
The contents of the specified Data Memory are rotated left by 1 bit with bit 7 rotated into bit 0.
[m].(i+1) ← [m].i; (i=0~6)
[m].0 ← [m].7
None
Rev. 1.10
187
January 19, 2015
HT45F77
Body Fat Scale 8-Bit Flash MCU
RLA [m]
Description
Operation
Affected flag(s)
Rotate Data Memory left with result in ACC
The contents of the specified Data Memory are rotated left by 1 bit with bit 7 rotated into bit 0.
The rotated result is stored in the Accumulator and the contents of the Data Memory remain
unchanged.
ACC.(i+1) ← [m].i; (i=0~6)
ACC.0 ← [m].7
None
RLC [m]
Description
Operation
Affected flag(s)
Rotate Data Memory left through Carry
The contents of the specified Data Memory and the carry flag are rotated left by 1 bit. Bit 7
replaces the Carry bit and the original carry flag is rotated into bit 0.
[m].(i+1) ← [m].i; (i=0~6)
[m].0 ← C
C ← [m].7
C
RLCA [m]
Description
Operation
Affected flag(s)
Rotate Data Memory left through Carry with result in ACC
Data in the specified Data Memory and the carry flag are rotated left by 1 bit. Bit 7 replaces the
Carry bit and the original carry flag is rotated into the bit 0. The rotated result is stored in the
Accumulator and the contents of the Data Memory remain unchanged.
ACC.(i+1) ← [m].i; (i=0~6)
ACC.0 ← C
C ← [m].7
C
RR [m]
Description
Operation
Affected flag(s)
Rotate Data Memory right
The contents of the specified Data Memory are rotated right by 1 bit with bit 0 rotated into bit 7.
[m].i ← [m].(i+1); (i=0~6)
[m].7 ← [m].0
None
RRA [m]
Description
Operation
Affected flag(s)
Rotate Data Memory right with result in ACC
Data in the specified Data Memory and the carry flag are rotated right by 1 bit with bit 0
rotated into bit 7. The rotated result is stored in the Accumulator and the contents of the
Data Memory remain unchanged.
ACC.i ← [m].(i+1); (i=0~6)
ACC.7 ← [m].0
None
RRC [m]
Description
Operation
Affected flag(s)
Rotate Data Memory right through Carry
The contents of the specified Data Memory and the carry flag are rotated right by 1 bit. Bit 0
replaces the Carry bit and the original carry flag is rotated into bit 7.
[m].i ← [m].(i+1); (i=0~6)
[m].7 ← C
C ← [m].0
C
Rev. 1.10
188
January 19, 2015
HT45F77
Body Fat Scale 8-Bit Flash MCU
RRCA [m]
Description
Operation
Affected flag(s)
Rotate Data Memory right through Carry with result in ACC
Data in the specified Data Memory and the carry flag are rotated right by 1 bit. Bit 0 replaces the Carry bit and the original carry flag is rotated into bit 7. The rotated result is stored in the Accumulator and the contents of the Data Memory remain unchanged.
ACC.i ← [m].(i+1); (i=0~6)
ACC.7 ← C
C ← [m].0
C
SBC A,[m]
Description
Operation
Affected flag(s)
Subtract Data Memory from ACC with Carry
The contents of the specified Data Memory and the complement of the carry flag are
subtracted from the Accumulator. The result is stored in the Accumulator. Note that if the result of subtraction is negative, the C flag will be cleared to 0, otherwise if the result is
positive or zero, the C flag will be set to 1.
ACC ← ACC − [m] − C
OV, Z, AC, C, SC, CZ
SBC A, x
Description
Operation
Affected flag(s)
Subtract immediate data from ACC with Carry
The immediate data and the complement of the carry flag are subtracted from the Accumulator. The result is stored in the Accumulator. Note that if the result of subtraction is negative, the C flag will be cleared to 0, otherwise if the result is positive or zero, the C flag will be set to 1.
ACC ← ACC - [m] - C
OV, Z, AC, C, SC, CZ
SBCM A,[m]
Description
Operation
Affected flag(s)
Subtract Data Memory from ACC with Carry and result in Data Memory
The contents of the specified Data Memory and the complement of the carry flag are subtracted from the Accumulator. The result is stored in the Data Memory. Note that if the result of subtraction is negative, the C flag will be cleared to 0, otherwise if the result is positive or zero, the C flag will be set to 1.
[m] ← ACC − [m] − C
OV, Z, AC, C, SC, CZ
SDZ [m]
Description
Operation
Affected flag(s)
Skip if decrement Data Memory is 0
The contents of the specified Data Memory are first decremented by 1. If the result is 0 the following instruction is skipped. As this requires the insertion of a dummy instruction while the next instruction is fetched, it is a two cycle instruction. If the result is not 0 the program proceeds with the following instruction.
[m] ← [m] − 1
Skip if [m]=0
None
SDZA [m]
Description
Operation
Affected flag(s)
Skip if decrement Data Memory is zero with result in ACC
The contents of the specified Data Memory are first decremented by 1. If the result is 0, the following instruction is skipped. The result is stored in the Accumulator but the specified Data Memory contents remain unchanged. As this requires the insertion of a dummy
instruction while the next instruction is fetched, it is a two cycle instruction. If the result is not 0,
the program proceeds with the following instruction.
ACC ← [m] − 1
Skip if ACC=0
None
Rev. 1.10
189
January 19, 2015
HT45F77
Body Fat Scale 8-Bit Flash MCU
SET [m]
Description
Operation
Affected flag(s)
Set Data Memory
Each bit of the specified Data Memory is set to 1.
[m] ← FFH
None
SET [m].i
Description
Operation
Affected flag(s)
Set bit of Data Memory
Bit i of the specified Data Memory is set to 1.
[m].i ← 1
None
SIZ [m]
Description
Operation
Affected flag(s)
Skip if increment Data Memory is 0
The contents of the specified Data Memory are first incremented by 1. If the result is 0, the
following instruction is skipped. As this requires the insertion of a dummy instruction while the next instruction is fetched, it is a two cycle instruction. If the result is not 0 the program
proceeds with the following instruction.
[m] ← [m] + 1
Skip if [m]=0
None
SIZA [m]
Description
Operation
Affected flag(s)
Skip if increment Data Memory is zero with result in ACC
The contents of the specified Data Memory are first incremented by 1. If the result is 0, the following instruction is skipped. The result is stored in the Accumulator but the specified
Data Memory contents remain unchanged. As this requires the insertion of a dummy
instruction while the next instruction is fetched, it is a two cycle instruction. If the result is not
0 the program proceeds with the following instruction.
ACC ← [m] + 1
Skip if ACC=0
None
SNZ [m].i
Description
Operation
Affected flag(s)
Skip if Data Memory is not 0
If the specified Data Memory is not 0, the following instruction is skipped. As this requires the
insertion of a dummy instruction while the next instruction is fetched, it is a two cycle instruction. If the result is 0 the program proceeds with the following instruction.
Skip if [m].i ≠ 0
None
SNZ [m]
Description
Operation
Affected flag(s)
Skip if Data Memory is not 0
If the specified Data Memory is not 0, the following instruction is skipped. As this requires the
insertion of a dummy instruction while the next instruction is fetched, it is a two cycle instruction. If the result is 0 the program proceeds with the following instruction.
Skip if [m]≠ 0
None
SUB A,[m]
Description
Operation
Affected flag(s)
Subtract Data Memory from ACC
The specified Data Memory is subtracted from the contents of the Accumulator. The result is stored in the Accumulator. Note that if the result of subtraction is negative, the C flag will be cleared to 0, otherwise if the result is positive or zero, the C flag will be set to 1.
ACC ← ACC − [m]
OV, Z, AC, C, SC, CZ
Rev. 1.10
190
January 19, 2015
HT45F77
Body Fat Scale 8-Bit Flash MCU
SUBM A,[m]
Description
Operation
Affected flag(s)
Subtract Data Memory from ACC with result in Data Memory
The specified Data Memory is subtracted from the contents of the Accumulator. The result is stored in the Data Memory. Note that if the result of subtraction is negative, the C flag will be cleared to 0, otherwise if the result is positive or zero, the C flag will be set to 1.
[m] ← ACC − [m]
OV, Z, AC, C, SC, CZ
SUB A,x
Description
Operation
Affected flag(s)
Subtract immediate data from ACC
The immediate data specified by the code is subtracted from the contents of the Accumulator. The result is stored in the Accumulator. Note that if the result of subtraction is negative, the C flag will be cleared to 0, otherwise if the result is positive or zero, the C flag will be set to 1.
ACC ← ACC − x
OV, Z, AC, C, SC, CZ
SWAP [m]
Description
Operation
Affected flag(s)
Swap nibbles of Data Memory
The low-order and high-order nibbles of the specified Data Memory are interchanged.
[m].3~[m].0 ↔ [m].7~[m].4
None
SWAPA [m]
Description
Operation
Affected flag(s)
Swap nibbles of Data Memory with result in ACC
The low-order and high-order nibbles of the specified Data Memory are interchanged. The result is stored in the Accumulator. The contents of the Data Memory remain unchanged.
ACC.3~ACC.0 ← [m].7~[m].4
ACC.7~ACC.4 ← [m].3~[m].0
None
SZ [m]
Description
Operation
Affected flag(s)
Skip if Data Memory is 0
If the contents of the specified Data Memory is 0, the following instruction is skipped. As this requires the insertion of a dummy instruction while the next instruction is fetched, it is a two cycle instruction. If the result is not 0 the program proceeds with the following instruction.
Skip if [m]=0
None
SZA [m]
Description
Operation
Affected flag(s)
Skip if Data Memory is 0 with data movement to ACC
The contents of the specified Data Memory are copied to the Accumulator. If the value is zero, the following instruction is skipped. As this requires the insertion of a dummy instruction while the next instruction is fetched, it is a two cycle instruction. If the result is not 0 the program proceeds with the following instruction.
ACC ← [m]
Skip if [m]=0
None
SZ [m].i
Description
Operation
Affected flag(s)
Skip if bit i of Data Memory is 0
If bit i of the specified Data Memory is 0, the following instruction is skipped. As this requires
the insertion of a dummy instruction while the next instruction is fetched, it is a two cycle
instruction. If the result is not 0, the program proceeds with the following instruction.
Skip if [m].i=0
None
Rev. 1.10
191
January 19, 2015
HT45F77
Body Fat Scale 8-Bit Flash MCU
TABRD [m]
Description
Operation
Affected flag(s)
Read table (current page) to TBLH and Data Memory
The low byte of the program code (current page) addressed by the table pointer (TBLP) is moved to the specified Data Memory and the high byte moved to TBLH.
[m] ← program code (low byte)
TBLH ← program code (high byte)
None
TABRDL [m]
Description
Operation
Affected flag(s)
Read table (last page) to TBLH and Data Memory
The low byte of the program code (last page) addressed by the table pointer (TBLP) is moved to the specified Data Memory and the high byte moved to TBLH.
[m] ← program code (low byte)
TBLH ← program code (high byte)
None
ITABRD [m]
Description
Operation
Affected flag(s)
Increment table pointer low byte first and read table to TBLH and Data Memory
Increment table pointer low byte, TBLP, first and then the program code addressed by the table pointer (TBHP and TBLP) is moved to the specified Data Memory and the high byte moved to TBLH.
[m] ← program code (low byte)
TBLH ← program code (high byte)
None
ITABRDL [m]
Description
Operation
Affected flag(s)
Increment table pointer low byte first and read table (last page) to TBLH and Data Memory
Increment table pointer low byte, TBLP, first and then the low byte of the program code (last page) addressed by the table pointer (TBLP) is moved to the specified Data Memory and the high byte moved to TBLH.
[m] ← program code (low byte)
TBLH ← program code (high byte)
None
XOR A,[m]
Description
Operation
Affected flag(s)
Logical XOR Data Memory to ACC
Data in the Accumulator and the specified Data Memory perform a bitwise logical XOR operation. The result is stored in the Accumulator.
ACC ← ACC ″XOR″ [m]
Z
XORM A,[m]
Description
Operation
Affected flag(s)
Logical XOR ACC to Data Memory
Data in the specified Data Memory and the Accumulator perform a bitwise logical XOR operation. The result is stored in the Data Memory.
[m] ← ACC ″XOR″ [m]
Z
XOR A,x
Description
Operation
Affected flag(s)
Logical XOR immediate data to ACC
Data in the Accumulator and the specified immediate data perform a bitwise logical XOR operation. The result is stored in the Accumulator.
ACC ← ACC ″XOR″ x
Z
Rev. 1.10
192
January 19, 2015
HT45F77
Body Fat Scale 8-Bit Flash MCU
Extended Instruction Definition
The extended instructions are used to directly access the data stored in any data memory sector.
LADC A,[m]
Description
Operation
Affected flag(s)
Add Data Memory to ACC with Carry
The contents of the specified Data Memory, Accumulator and the carry flag are added.
The result is stored in the Accumulator.
ACC ← ACC + [m] + C
OV, Z, AC, C, SC
LADCM A,[m]
Description
Operation
Affected flag(s)
Add ACC to Data Memory with Carry
The contents of the specified Data Memory, Accumulator and the carry flag are added. The result is stored in the specified Data Memory.
[m] ← ACC + [m] + C
OV, Z, AC, C, SC
LADD A,[m]
Description
The contents of the specified Data Memory and the Accumulator are added.
The result is stored in the Accumulator.
Operation
Affected flag(s)
ACC ← ACC + [m]
OV, Z, AC, C, SC
LADDM A,[m]
Description
Operation
Affected flag(s)
Add ACC to Data Memory
The contents of the specified Data Memory and the Accumulator are added. The result is stored in the specified Data Memory.
[m] ← ACC + [m]
OV, Z, AC, C, SC
LAND A,[m]
Description
Operation
Affected flag(s)
Logical AND Data Memory to ACC
Data in the Accumulator and the specified Data Memory perform a bitwise logical AND operation. The result is stored in the Accumulator.
ACC ← ACC ″AND″ [m]
Z
LANDM A,[m]
Description
Operation
Affected flag(s)
Logical AND ACC to Data Memory
Data in the specified Data Memory and the Accumulator perform a bitwise logical AND
operation. The result is stored in the Data Memory.
[m] ← ACC ″AND″ [m]
Z
LCLR [m]
Description
Operation
Affected flag(s)
Clear Data Memory
Each bit of the specified Data Memory is cleared to 0.
[m] ← 00H
None
LCLR [m].i
Description
Operation
Affected flag(s)
Clear bit of Data Memory
Bit i of the specified Data Memory is cleared to 0.
[m].i ← 0
None
Rev. 1.10
Add Data Memory to ACC
193
January 19, 2015
HT45F77
Body Fat Scale 8-Bit Flash MCU
LCPL [m]
Description
Operation
Affected flag(s)
Complement Data Memory
Each bit of the specified Data Memory is logically complemented (1′s complement). Bits which
previously contained a 1 are changed to 0 and vice versa.
[m] ← [m]
Z
LCPLA [m]
Description
Operation
Affected flag(s)
Complement Data Memory with result in ACC
Each bit of the specified Data Memory is logically complemented (1′s complement). Bits which
previously contained a 1 are changed to 0 and vice versa. The complemented result is stored in
the Accumulator and the contents of the Data Memory remain unchanged.
ACC ← [m]
Z
LDAA [m]
Description
Operation
Affected flag(s)
Decimal-Adjust ACC for addition with result in Data Memory
Convert the contents of the Accumulator value to a BCD (Binary Coded Decimal) value
resulting from the previous addition of two BCD variables. If the low nibble is greater than 9
or if AC flag is set, then a value of 6 will be added to the low nibble. Otherwise the low nibble
remains unchanged. If the high nibble is greater than 9 or if the C flag is set, then a value of 6
will be added to the high nibble. Essentially, the decimal conversion is performed by adding
00H, 06H, 60H or 66H depending on the Accumulator and flag conditions. Only the C flag
may be affected by this instruction which indicates that if the original BCD sum is greater than
100, it allows multiple precision decimal addition.
[m] ← ACC + 00H or
[m] ← ACC + 06H or [m] ← ACC + 60H or
[m] ← ACC + 66H
C
LDEC [m]
Description
Operation
Affected flag(s)
Decrement Data Memory
Data in the specified Data Memory is decremented by 1.
[m] ← [m] − 1
Z
LDECA [m]
Description
Operation
Affected flag(s)
Decrement Data Memory with result in ACC
Data in the specified Data Memory is decremented by 1. The result is stored in the
Accumulator. The contents of the Data Memory remain unchanged.
ACC ← [m] − 1
Z
LINC [m]
Description
Operation
Affected flag(s)
Increment Data Memory
Data in the specified Data Memory is incremented by 1.
[m] ← [m] + 1
Z
LINCA [m]
Description
Operation
Affected flag(s)
Increment Data Memory with result in ACC
Data in the specified Data Memory is incremented by 1. The result is stored in the Accumulator.
The contents of the Data Memory remain unchanged.
ACC ← [m] + 1
Z
Rev. 1.10
194
January 19, 2015
HT45F77
Body Fat Scale 8-Bit Flash MCU
LMOV A,[m]
Description
Operation
Affected flag(s)
Move Data Memory to ACC
The contents of the specified Data Memory are copied to the Accumulator.
ACC ← [m]
None
LMOV [m],A
Description
Operation
Affected flag(s)
Move ACC to Data Memory
The contents of the Accumulator are copied to the specified Data Memory.
[m] ← ACC
None
LOR A,[m]
Description
Operation
Affected flag(s)
Logical OR Data Memory to ACC
Data in the Accumulator and the specified Data Memory perform a bitwise
logical OR operation. The result is stored in the Accumulator.
ACC ← ACC ″OR″ [m]
Z
LORM A,[m]
Description
Operation
Affected flag(s)
Logical OR ACC to Data Memory
Data in the specified Data Memory and the Accumulator perform a bitwise logical OR operation. The result is stored in the Data Memory.
[m] ← ACC ″OR″ [m]
Z
LRL [m]
Description
Operation
Affected flag(s)
Rotate Data Memory left
The contents of the specified Data Memory are rotated left by 1 bit with bit 7 rotated into bit 0.
[m].(i+1) ← [m].i; (i=0~6)
[m].0 ← [m].7
None
LRLA [m]
Description
Operation
Affected flag(s)
Rotate Data Memory left with result in ACC
The contents of the specified Data Memory are rotated left by 1 bit with bit 7 rotated into bit 0.
The rotated result is stored in the Accumulator and the contents of the Data Memory remain
unchanged.
ACC.(i+1) ← [m].i; (i=0~6)
ACC.0 ← [m].7
None
LRLC [m]
Description
Operation
Affected flag(s)
Rotate Data Memory left through Carry
The contents of the specified Data Memory and the carry flag are rotated left by 1 bit. Bit 7
replaces the Carry bit and the original carry flag is rotated into bit 0.
[m].(i+1) ← [m].i; (i=0~6)
[m].0 ← C
C ← [m].7
C
LRLCA [m]
Description
Operation
Affected flag(s)
Rotate Data Memory left through Carry with result in ACC
Data in the specified Data Memory and the carry flag are rotated left by 1 bit. Bit 7 replaces the
Carry bit and the original carry flag is rotated into the bit 0. The rotated result is stored in the
Accumulator and the contents of the Data Memory remain unchanged.
ACC.(i+1) ← [m].i; (i=0~6)
ACC.0 ← C
C ← [m].7
C
Rev. 1.10
195
January 19, 2015
HT45F77
Body Fat Scale 8-Bit Flash MCU
LRR [m]
Description
Operation
Affected flag(s)
Rotate Data Memory right
The contents of the specified Data Memory are rotated right by 1 bit with bit 0 rotated into bit 7.
[m].i ← [m].(i+1); (i=0~6)
[m].7 ← [m].0
None
LRRA [m]
Description
Operation
Affected flag(s)
Rotate Data Memory right with result in ACC
Data in the specified Data Memory and the carry flag are rotated right by 1 bit with bit 0
rotated into bit 7. The rotated result is stored in the Accumulator and the contents of the
Data Memory remain unchanged.
ACC.i ← [m].(i+1); (i=0~6)
ACC.7 ← [m].0
None
LRRC [m]
Description
Operation
Affected flag(s)
Rotate Data Memory right through Carry
The contents of the specified Data Memory and the carry flag are rotated right by 1 bit. Bit 0
replaces the Carry bit and the original carry flag is rotated into bit 7.
[m].i ← [m].(i+1); (i=0~6)
[m].7 ← C
C ← [m].0
C
LRRCA [m]
Description
Operation
Affected flag(s)
Rotate Data Memory right through Carry with result in ACC
Data in the specified Data Memory and the carry flag are rotated right by 1 bit. Bit 0 replaces the Carry bit and the original carry flag is rotated into bit 7. The rotated result is stored in the Accumulator and the contents of the Data Memory remain unchanged.
ACC.i ← [m].(i+1); (i=0~6)
ACC.7 ← C
C ← [m].0
C
LSBC A,[m]
Description
Operation
Affected flag(s)
Subtract Data Memory from ACC with Carry
The contents of the specified Data Memory and the complement of the carry flag are
subtracted from the Accumulator. The result is stored in the Accumulator. Note that if the result of subtraction is negative, the C flag will be cleared to 0, otherwise if the result is
positive or zero, the C flag will be set to 1.
ACC ← ACC − [m] − C
OV, Z, AC, C, SC, CZ
LSBCM A,[m]
Description
Operation
Affected flag(s)
Subtract Data Memory from ACC with Carry and result in Data Memory
The contents of the specified Data Memory and the complement of the carry flag are subtracted from the Accumulator. The result is stored in the Data Memory. Note that if the result of subtraction is negative, the C flag will be cleared to 0, otherwise if the result is positive or zero, the C flag will be set to 1.
[m] ← ACC − [m] − C
OV, Z, AC, C, SC, CZ
Rev. 1.10
196
January 19, 2015
HT45F77
Body Fat Scale 8-Bit Flash MCU
LSDZ [m]
Description
Operation
Affected flag(s)
Skip if decrement Data Memory is 0
The contents of the specified Data Memory are first decremented by 1. If the result is 0 the following instruction is skipped. As this requires the insertion of a dummy instruction while the next instruction is fetched, it is a two cycle instruction. If the result is not 0 the program proceeds with the following instruction.
[m] ← [m] − 1
Skip if [m]=0
None
LSDZA [m]
Description
Operation
Affected flag(s)
Skip if decrement Data Memory is zero with result in ACC
The contents of the specified Data Memory are first decremented by 1. If the result is 0, the following instruction is skipped. The result is stored in the Accumulator but the specified Data Memory contents remain unchanged. As this requires the insertion of a dummy
instruction while the next instruction is fetched, it is a two cycle instruction. If the result is not 0,
the program proceeds with the following instruction.
ACC ← [m] − 1
Skip if ACC=0
None
LSET [m]
Description
Operation
Affected flag(s)
Set Data Memory
Each bit of the specified Data Memory is set to 1.
[m] ← FFH
None
LSET [m].i
Description
Operation
Affected flag(s)
Set bit of Data Memory
Bit i of the specified Data Memory is set to 1.
[m].i ← 1
None
LSIZ [m]
Description
Operation
Affected flag(s)
Skip if increment Data Memory is 0
The contents of the specified Data Memory are first incremented by 1. If the result is 0, the
following instruction is skipped. As this requires the insertion of a dummy instruction while the next instruction is fetched, it is a two cycle instruction. If the result is not 0 the program
proceeds with the following instruction.
[m] ← [m] + 1
Skip if [m]=0
None
LSIZA [m]
Description
Operation
Affected flag(s)
Skip if increment Data Memory is zero with result in ACC
The contents of the specified Data Memory are first incremented by 1. If the result is 0, the following instruction is skipped. The result is stored in the Accumulator but the specified
Data Memory contents remain unchanged. As this requires the insertion of a dummy
instruction while the next instruction is fetched, it is a two cycle instruction. If the result is not
0 the program proceeds with the following instruction.
ACC ← [m] + 1
Skip if ACC=0
None
LSNZ [m].i
Description
Operation
Affected flag(s)
Skip if Data Memory is not 0
If the specified Data Memory is not 0, the following instruction is skipped. As this requires the
insertion of a dummy instruction while the next instruction is fetched, it is a two cycle instruction. If the result is 0 the program proceeds with the following instruction.
Skip if [m].i ≠ 0
None
Rev. 1.10
197
January 19, 2015
HT45F77
Body Fat Scale 8-Bit Flash MCU
LSNZ [m]
Description
Operation
Affected flag(s)
Skip if Data Memory is not 0
If the content of the specified Data Memory is not 0, the following instruction is skipped. As this requires the insertion of a dummy instruction while the next instruction is fetched, it is a two cycle instruction. If the result is 0 the program proceeds with the following instruction.
Skip if [m] ≠ 0
None
LSUB A,[m]
Description
Operation
Affected flag(s)
Subtract Data Memory from ACC
The specified Data Memory is subtracted from the contents of the Accumulator. The result is stored in the Accumulator. Note that if the result of subtraction is negative, the C flag will be cleared to 0, otherwise if the result is positive or zero, the C flag will be set to 1.
ACC ← ACC − [m]
OV, Z, AC, C, SC, CZ
LSUBM A,[m]
Description
Operation
Affected flag(s)
Subtract Data Memory from ACC with result in Data Memory
The specified Data Memory is subtracted from the contents of the Accumulator. The result is stored in the Data Memory. Note that if the result of subtraction is negative, the C flag will be cleared to 0, otherwise if the result is positive or zero, the C flag will be set to 1.
[m] ← ACC − [m]
OV, Z, AC, C, SC, CZ
LSWAP [m]
Description
Operation
Affected flag(s)
Swap nibbles of Data Memory
The low-order and high-order nibbles of the specified Data Memory are interchanged.
[m].3~[m].0 ↔ [m].7~[m].4
None
LSWAPA [m]
Description
Operation
Affected flag(s)
Swap nibbles of Data Memory with result in ACC
The low-order and high-order nibbles of the specified Data Memory are interchanged. The result is stored in the Accumulator. The contents of the Data Memory remain unchanged.
ACC.3~ACC.0 ← [m].7~[m].4
ACC.7~ACC.4 ← [m].3~[m].0
None
LSZ [m]
Description
Operation
Affected flag(s)
Skip if Data Memory is 0
If the contents of the specified Data Memory is 0, the following instruction is skipped. As this requires the insertion of a dummy instruction while the next instruction is fetched, it is a two cycle instruction. If the result is not 0 the program proceeds with the following instruction.
Skip if [m]=0
None
LSZA [m]
Description
Operation
Affected flag(s)
Skip if Data Memory is 0 with data movement to ACC
The contents of the specified Data Memory are copied to the Accumulator. If the value is zero, the following instruction is skipped. As this requires the insertion of a dummy instruction while the next instruction is fetched, it is a two cycle instruction. If the result is not 0 the program proceeds with the following instruction.
ACC ← [m]
Skip if [m]=0
None
Rev. 1.10
198
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HT45F77
Body Fat Scale 8-Bit Flash MCU
LSZ [m].i
Description
Operation
Affected flag(s)
Skip if bit i of Data Memory is 0
If bit i of the specified Data Memory is 0, the following instruction is skipped. As this requires
the insertion of a dummy instruction while the next instruction is fetched, it is a two cycle
instruction. If the result is not 0, the program proceeds with the following instruction.
Skip if [m].i=0
None
LTABRD [m]
Description
Operation
Affected flag(s)
Read table (current page) to TBLH and Data Memory
The low byte of the program code (current page) addressed by the table pointer (TBLP) is moved to the specified Data Memory and the high byte moved to TBLH.
[m] ← program code (low byte)
TBLH ← program code (high byte)
None
LTABRDL [m]
Description
Operation
Affected flag(s)
Read table (last page) to TBLH and Data Memory
The low byte of the program code (last page) addressed by the table pointer (TBLP) is moved to the specified Data Memory and the high byte moved to TBLH.
[m] ← program code (low byte)
TBLH ← program code (high byte)
None
LITABRD [m]
Description
Operation
Increment table pointer low byte first and read table to TBLH and Data Memory
Increment table pointer low byte, TBLP, first and then the program code addressed by the table pointer (TBHP and TBLP) is moved to the specified Data Memory and the high byte moved to TBLH.
[m] ← program code (low byte)
TBLH ← program code (high byte)
Affected flag(s)
None
LITABRDL [m]
Description
Operation
Affected flag(s)
Increment table pointer low byte first and read table (last page) to TBLH and Data Memory
Increment table pointer low byte, TBLP, first and then the low byte of the program code (last page) addressed by the table pointer (TBLP) is moved to the specified Data Memory and the high byte moved to TBLH.
[m] ← program code (low byte)
TBLH ← program code (high byte)
None
LXOR A,[m]
Description
Operation
Affected flag(s)
Logical XOR Data Memory to ACC
Data in the Accumulator and the specified Data Memory perform a bitwise logical XOR operation. The result is stored in the Accumulator.
ACC ← ACC ″XOR″ [m]
Z
LXORM A,[m]
Description
Operation
Affected flag(s)
Logical XOR ACC to Data Memory
Data in the specified Data Memory and the Accumulator perform a bitwise logical XOR operation. The result is stored in the Data Memory.
[m] ← ACC ″XOR″ [m]
Z
Rev. 1.10
199
January 19, 2015
HT45F77
Body Fat Scale 8-Bit Flash MCU
Package Information
Note that the package information provided here is for consultation purposes only. As this
information may be updated at regular intervals users are reminded to consult the Holtek website for
the latest version of the package information.
Additional supplementary information with regard to packaging is listed below. Click on the relevant
section to be transferred to the relevant website page.
• Further Package Information (include Outline Dimensions, Product Tape and Reel Specifications)
• Packing Meterials Information
• Carton information
Rev. 1.10
200
January 19, 2015
HT45F77
Body Fat Scale 8-Bit Flash MCU
64-pin LQFP (7mm × 7mm) Outline Dimensions
Symbol
Nom.
Max.
A
—
0.354 BSC
—
B
—
0.276 BSC
—
C
—
0.354 BSC
—
D
—
0.276 BSC
—
E
—
0.016 BSC
—
F
0.005
0.007
0.009
G
0.053
0.055
0.057
H
—
—
0.063
I
0.002
—
0.006
J
0.018
0.024
0.030
K
0.004
—
0.008
α
0°
—
7°
Symbol
Rev. 1.10
Dimensions in inch
Min.
Dimensions in mm
Min.
Nom.
Max.
A
—
9.00 BSC
—
B
—
7.00 BSC
—
C
—
9.00 BSC
—
D
—
7.00 BSC
—
E
—
0.40 BSC
—
F
0.13
0.18
0.23
G
1.35
1.40
1.45
H
—
—
1.60
I
0.05
—
0.15
J
0.45
0.60
0.75
K
0.09
—
0.20
α
0°
—
7°
201
January 19, 2015
HT45F77
Body Fat Scale 8-Bit Flash MCU
80-pin LQFP (10mm × 10mm) Outline Dimensions
Symbol
Min.
Nom.
Max.
A
—
0.472 BSC
—
B
—
0.394 BSC
—
C
—
0.472 BSC
—
D
—
0.394 BSC
—
E
—
0.0157 BSC
—
F
0.007
0.009
0.011
G
0.053
0.055
0.057
H
—
—
0.063
I
0.002
—
0.006
J
0.018
0.024
0.030
K
0.004
—
0.008
α
0°
—
7°
Symbol
Rev. 1.10
Dimensions in inch
Dimensions in mm
Min.
Nom.
Max.
A
—
12 BSC
—
B
—
10 BSC
—
C
—
12 BSC
—
D
—
10 BSC
—
E
—
0.4 BSC
—
F
0.13
0.18
0.23
G
1.35
1.4
1.45
H
—
—
1.60
I
0.05
—
0.15
J
0.45
0.60
0.75
K
0.09
—
0.20
α
0°
—
7°
202
January 19, 2015
HT45F77
Body Fat Scale 8-Bit Flash MCU
Copyright© 2015 by HOLTEK SEMICONDUCTOR INC.
The information appearing in this Data Sheet is believed to be accurate at the time
of publication. However, Holtek assumes no responsibility arising from the use of
the specifications described. The applications mentioned herein are used solely
for the purpose of illustration and Holtek makes no warranty or representation that
such applications will be suitable without further modification, nor recommends
the use of its products for application that may present a risk to human life due to
malfunction or otherwise. Holtek's products are not authorized for use as critical
components in life support devices or systems. Holtek reserves the right to alter
its products without prior notification. For the most up-to-date information, please
visit our web site at http://www.holtek.com.tw.
Rev. 1.10
203
January 19, 2015