HT66F20-1/HT66F30-1 HT68F20-1/HT68F30-1

Enhanced Flash Type 8-Bit MCU with EEPROM
HT66F20-1/HT66F30-1
HT68F20-1/HT68F30-1
Revision: V1.30
Date: ������������
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
Table of Contents
Features............................................................................................................. 7
CPU Features.......................................................................................................................... 7
Peripheral Features.................................................................................................................. 7
General Description.......................................................................................... 8
Selection Table.................................................................................................. 8
Block Diagram................................................................................................... 9
Pin Assignment............................................................................................... 10
Pin Description............................................................................................... 12
Absolute Maximum Ratings........................................................................... 16
D.C. Characteristics........................................................................................ 16
HT66F20-1/HT66F30-1.......................................................................................................... 16
HT68F20-1/HT68F30-1.......................................................................................................... 18
A.C. Characteristics........................................................................................ 19
HT66F20-1/HT66F30-1.......................................................................................................... 19
HT68F20-1/HT68F30-1.......................................................................................................... 21
A/D Converter Characteristics....................................................................... 22
HT66F20-1/HT66F30-1.......................................................................................................... 22
Comparator Electrical Characteristics......................................................... 22
Power on Reset Electrical Characteristics................................................... 23
System Architecture....................................................................................... 23
Clocking and Pipelining.......................................................................................................... 23
Program Counter.................................................................................................................... 24
Stack...................................................................................................................................... 25
Arithmetic and Logic Unit – ALU............................................................................................ 25
Flash Program Memory.................................................................................. 26
Structure................................................................................................................................. 26
Special Vectors...................................................................................................................... 26
Look-up Table......................................................................................................................... 27
Table Program Example......................................................................................................... 27
In Circuit Programming.......................................................................................................... 28
Data Memory................................................................................................... 29
Structure................................................................................................................................. 29
Rev. 1.30
2
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
Special Function Register Description......................................................... 35
Indirect Addressing Registers – IAR0, IAR1.......................................................................... 35
Memory Pointers – MP0, MP1............................................................................................... 35
Bank Pointer – BP.................................................................................................................. 36
Accumulator – ACC................................................................................................................ 36
Program Counter Low Register – PCL................................................................................... 36
Look-up Table Registers – TBLP, TBHP, TBLH...................................................................... 37
Status Register – STATUS..................................................................................................... 37
EEPROM Data Memory................................................................................... 38
EEPROM Data Memory Structure......................................................................................... 38
EEPROM Registers............................................................................................................... 39
Reading Data from the EEPROM.......................................................................................... 41
Writing Data to the EEPROM................................................................................................. 41
Write Protection...................................................................................................................... 41
EEPROM Interrupt................................................................................................................. 41
Programming Consideration.................................................................................................. 42
Programming Examples......................................................................................................... 42
Oscillator......................................................................................................... 43
Oscillator Overview................................................................................................................ 43
System Clock Configurations................................................................................................. 43
External Crystal/Ceramic Oscillator – HXT............................................................................ 44
External RC Oscillator – ERC................................................................................................ 45
Internal RC Oscillator – HIRC................................................................................................ 45
External 32.768kHz Crystal Oscillator – LXT......................................................................... 46
LXT Oscillator Low Power Function....................................................................................... 47
Internal 32kHz Oscillator – LIRC............................................................................................ 47
Supplementary Clocks........................................................................................................... 47
Operating Modes and System Clocks.......................................................... 48
System Clocks....................................................................................................................... 48
System Operation Modes....................................................................................................... 50
Control Register..................................................................................................................... 51
Fast Wake-up......................................................................................................................... 52
Operating Mode Switching..................................................................................................... 54
Standby Current Considerations............................................................................................ 57
Wake-up................................................................................................................................. 57
Programming Considerations................................................................................................. 58
Watchdog Timer.............................................................................................. 58
Watchdog Timer Clock Source............................................................................................... 58
Watchdog Timer Control Register.......................................................................................... 59
Watchdog Timer Operation.................................................................................................... 60
Reset and Initialisation................................................................................... 61
Reset Functions..................................................................................................................... 61
Reset Initial Conditions.......................................................................................................... 64
Rev. 1.30
3
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
Input/Output Ports.......................................................................................... 71
I/O Port Register List.............................................................................................................. 71
Pull-high Resistors................................................................................................................. 72
Port A Wake-up...................................................................................................................... 73
I/O Port Control Registers...................................................................................................... 73
Pin-remapping Functions....................................................................................................... 74
Pin-remapping Registers........................................................................................................ 74
I/O Pin Structures................................................................................................................... 75
Programming Considerations................................................................................................. 76
Timer Modules – TM....................................................................................... 76
Introduction............................................................................................................................ 76
TM Operation......................................................................................................................... 77
TM Clock Source.................................................................................................................... 77
TM Interrupts.......................................................................................................................... 77
TM External Pins.................................................................................................................... 78
TM Input/Output Pin Control.................................................................................................. 78
Programming Considerations................................................................................................. 82
Compact Type TM – CTM............................................................................... 83
Compact TM Operation.......................................................................................................... 83
Compact Type TM Register Description................................................................................ 84
Compact Type TM Operating Modes..................................................................................... 87
Compare Match Output Mode................................................................................................ 87
Timer/Counter Mode.............................................................................................................. 90
PWM Output Mode................................................................................................................. 90
Standard Type TM – STM............................................................................... 93
Standard TM Operation.......................................................................................................... 93
Standard Type TM Register Description................................................................................ 94
Standard Type TM Operating Modes..................................................................................... 98
Compare Match Output Mode................................................................................................ 98
Timer/Counter Mode............................................................................................................ 101
PWM Output Mode............................................................................................................... 101
Single Pulse Mode............................................................................................................... 104
Capture Input Mode............................................................................................................. 106
Enhanced Type TM – ETM............................................................................ 107
Enhanced TM Operation...................................................................................................... 107
Enhanced Type TM Register Description............................................................................. 108
Enhanced Type TM Operating Modes..................................................................................114
Compare Match Output Mode...............................................................................................115
Timer/Counter Mode............................................................................................................ 120
PWM Output Mode............................................................................................................... 120
Single Pulse Output Mode................................................................................................... 126
Capture Input Mode............................................................................................................. 128
Rev. 1.30
4
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
Analog to Digital Converter......................................................................... 131
A/D Overview....................................................................................................................... 131
A/D Converter Register Description..................................................................................... 131
A/D Converter Data Registers – ADRL, ADRH.................................................................... 132
A/D Converter Control Registers – ADCR0, ADCR1, ACERL.............................................. 132
A/D Operation...................................................................................................................... 135
A/D Input Pins...................................................................................................................... 136
Summary of A/D Conversion Steps...................................................................................... 137
Programming Considerations............................................................................................... 138
A/D Transfer Function.......................................................................................................... 138
A/D Programming Example.................................................................................................. 139
Comparators................................................................................................. 141
Comparator Operation......................................................................................................... 141
Comparator Registers.......................................................................................................... 141
Comparator Interrupt............................................................................................................ 144
Programming Considerations............................................................................................... 144
Serial Interface Module – SIM...................................................................... 144
SPI Interface........................................................................................................................ 144
I2C Interface......................................................................................................................... 151
I2C Bus Start Signal.............................................................................................................. 157
Slave Address...................................................................................................................... 157
I2C Bus Read/Write Signal................................................................................................... 157
I2C Bus Slave Address Acknowledge Signal........................................................................ 157
I2C Bus Data and Acknowledge Signal................................................................................ 158
Peripheral Clock Output............................................................................... 160
Peripheral Clock Operation.................................................................................................. 160
Interrupts....................................................................................................... 161
Interrupt Registers................................................................................................................ 161
Interrupt Operation............................................................................................................... 169
External Interrupt.................................................................................................................. 172
Comparator Interrupt............................................................................................................ 172
Multi-function Interrupt......................................................................................................... 172
A/D Converter Interrupt........................................................................................................ 173
Time Base Interrupts............................................................................................................ 173
Serial Interface Module Interrupts........................................................................................ 175
External Peripheral Interrupt................................................................................................ 175
EEPROM Interrupt............................................................................................................... 175
LVD Interrupt........................................................................................................................ 176
TM Interrupts........................................................................................................................ 176
Interrupt Wake-up Function.................................................................................................. 176
Programming Considerations............................................................................................... 177
Rev. 1.30
5
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
Low Voltage Detector – LVD........................................................................ 178
LVD Register........................................................................................................................ 178
LVD Operation...................................................................................................................... 179
SCOM Function for LCD............................................................................... 180
LCD Operation..................................................................................................................... 180
LCD Bias Control................................................................................................................. 181
Configuration Options.................................................................................. 182
Application Circuits...................................................................................... 183
HT66F20-1/HT66F30-1........................................................................................................ 183
HT68F20-1/HT68F30-1........................................................................................................ 184
Instruction Set............................................................................................... 185
Introduction.......................................................................................................................... 185
Instruction Timing................................................................................................................. 185
Moving and Transferring Data.............................................................................................. 185
Arithmetic Operations........................................................................................................... 185
Logical and Rotate Operation.............................................................................................. 186
Branches and Control Transfer............................................................................................ 186
Bit Operations...................................................................................................................... 186
Table Read Operations........................................................................................................ 186
Other Operations.................................................................................................................. 186
Instruction Set Summary............................................................................. 187
Table Conventions................................................................................................................ 187
Instruction Definition.................................................................................... 189
Package Information.................................................................................... 198
16-pin DIP (300mil) Outline Dimensions.............................................................................. 199
16-pin NSOP (150mil) Outline Dimensions.......................................................................... 201
16-pin SSOP (150mil) Outline Dimensions.......................................................................... 202
20-pin DIP (300mil) Outline Dimensions.............................................................................. 203
20-pin SOP (300mil) Outline Dimensions............................................................................ 205
20-pin SSOP (150mil) Outline Dimensions.......................................................................... 206
24-pin SKDIP (300mil) Outline Dimensions......................................................................... 207
24-pin SOP (300mil) Outline Dimensions............................................................................ 209
24-pin SSOP(150mil) Outline Dimensions........................................................................... 210
Rev. 1.30
6
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
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
• Five oscillators:
♦♦ External Crystal - HXT
♦♦ External 32.768kHz Crystal - LXT
♦♦ External RC - ERC
♦♦ Internal RC - HIRC
♦♦ Internal 32kHz RC - LIRC
• Multi-mode operation: NORMAL, SLOW, IDLE and SLEEP
• Fully integrated internal 4MHz, 8MHz and 12MHz oscillator requires no external components
• All instructions executed in one or two instruction cycles
• Table read instructions
• 63 powerful instructions
• 4-level subroutine nesting
• Bit manipulation instruction
Peripheral Features
• Flash Program Memory: 1K×16 ~ 2K×16
• Data Memory: 64×8 ~ 96×8
• EEPROM Memory: 32×8 ~ 64×8
• Watchdog Timer function
• Up to 22 bidirectional I/O lines
• Software controlled 4-SCOM lines LCD driver with 1/2 bias
• Dual pin-shared external interrupts
• Multiple Timer Module for time measure, input capture, compare match output, PWM output or
single pulse output function
• Serial Interfaces Module with Dual SPI and I2C interfaces
• Dual Comparator functions
• Dual Time-Base functions for generation of fixed time interrupt signals
• 8-channel 12-bit resolution A/D converter – HT66F30-1/HT66F20-1
• Low voltage reset function
• Low voltage detect function
• Wide range of available package types
• Flash program memory can be re-programmed up to 100,000 times
• Flash program memory data retention > 10 years
• EEPROM data memory can be re-programmed up to 1,000,000 times
• EEPROM data memory data retention > 10 years
Rev. 1.30
7
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
General Description
The HT66Fx0-1 and HT68Fx0-1 series are Flash Memory type with 8-bit high performance
RISC architecture microcontrollers, designed for a wide range of applications. Offering users the
convenience of Flash Memory multi-programming features, these devices also include a wide range
of functions and features. Other memory includes an area of RAM Data Memory 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 12-bit A/D converter and dual comparator functions.
Multiple and extremely flexible Timer Modules provide timing, pulse generation and PWM
generation functions. Communication with the outside world is catered for by including fully
integrated SPI or I2C interface functions, two popular interfaces which provide designers with a
means of easy communication with external peripheral hardware. Protective features such as an
internal Watchdog Timer, Low Voltage Reset and Low Voltage Detector coupled with excellent
noise immunity and ESD protection ensure that reliable operation is maintained in hostile electrical
environments.
A full choice of HXT, LXT, ERC, 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 devices will find excellent use in applications such as electronic metering,
environmental monitoring, handheld instruments, household appliances, electronically controlled
tools, motor driving in addition to many others.
Selection Table
Most features are common to all devices. The main features distinguishing them are Program
Memory, Data Memory capacity, TM feature, A/D function, I/O count and package tyhpes. The
following table summarises the main features of each device.
Part No.
Program
Data
Data
Memory Memory EEPROM
I/O
Ext.
Interrupt
A/D
Timer
Module
SPI/ Time
Comp. Stack
I2C Base
Package
HT68F20-1
1K×16
64×8
32×8
18
2
---
10-bit CTM×1
10-bit STM×1
√
2
2
4
16DIP/NSOP/SSOP
20DIP/SOP/SSOP
HT68F30-1
2K×16
96×8
64×8
22
2
---
10-bit CTM×1
10-bit ETM×1
√
2
2
4
16DIP/NSOP/SSOP
20DIP/SOP/SSOP
24SKDIP/SOP/
SSOP
HT66F20-1
1K×16
64×8
32×8
18
2
12-bitx8
10-bit CTM×1
10-bit STM×1
√
2
2
4
16DIP/NSOP/SSOP
20DIP/SOP/SSOP
HT66F30-1
2K×16
96×8
64×8
22
2
12-bitx8
10-bit CTM×1
10-bit ETM×1
√
2
2
4
16DIP/NSOP/SSOP
20DIP/SOP/SSOP
24SKDIP/SOP/
SSOP
Rev. 1.30
8
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
Block Diagram
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Note: Only the HT66F30-1 and HT66F20-1 devices have A/D function.
Rev. 1.30
9
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
Pin Assignment
HT66F20-1 & HT66F30-1
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Note: 1. Bracketed pin names indicate non-default pinout remapping locations.
2. If the pin-shared pin functions have multiple outputs simultaneously, its pin names at the right side of the
“/” sign can be used for higher priority.
Rev. 1.30
10
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
HT68F20-1 & HT68F30-1
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Note: 1. Bracketed pin names indicate non-default pinout remapping locations.
2. If the pin-shared pin functions have multiple outputs simultaneously, its pin names at the right side of the
“/” sign can be used for higher priority.
Rev. 1.30
11
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
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.
HT66F20-1
Pin Name
Function
OP
I/T
O/T
Pin-Shared Mapping
PAWU
PAPU
ST
CMOS
—
—
PA0~PA7
Port A
PB0~PB5
Port B
PBPU
ST
CMOS
PC0~PC3
Port C
PCPU
ST
CMOS
AN0~AN7
ADC input
ACERL
AN
—
PA0~PA7
VREF
ADC reference input
ADCR1
AN
—
PB5
C0-, C1-
Comparator 0, 1 input
—
PA3, PC3
Comparator 0, 1 input
AN
—
PA2, PC2
C0X, C1X
Comparator 0, 1 output
CP0C
CP1C
AN
C0+, C1+
—
CMOS
PA0, PA5
TCK0, TCK1
TM0, TM1 input
—
ST
—
PA2, PA4
TP0_0
TM0 I/O
TMPC0
ST
CMOS
PA0
TP1_0, TP1_1
TM1 I/O
TMPC0
ST
CMOS
PA1, PC0
INT0, INT1
Ext. Interrupt 0, 1
—
ST
—
PA3, PA4
PC3
—
PINT
Peripheral Interrupt
—
ST
—
PCK
Peripheral Clock output
—
—
CMOS
PC2
SDI
SPI Data input
—
ST
—
PA6
SDO
SPI Data output
—
—
CMOS
PA5
SCS
SPI Slave Select
—
ST
CMOS
PB5
SCK
SPI Serial Clock
—
ST
CMOS
PA7
SCL
I2C Clock
—
ST
NMOS
PA7
SDA
I C Data
PA6
2
SCOM0~SCOM3 SCOM0~SCOM3
OSC1
HXT/ERC pin
—
ST
NMOS
SCOMC
—
SCOM
CO
HXT
—
PC0, PC1, PC2, PC3
PB1
OSC2
HXT pin
CO
—
HXT
PB2
XT1
LXT pin
CO
LXT
—
PB3
XT2
LXT pin
CO
—
LXT
PB4
RES
Reset input
CO
ST
—
PB0
VDD
Power supply*
—
PWR
—
—
AVDD
ADC power supply*
—
PWR
—
—
VSS
Ground**
—
PWR
—
—
AVSS
ADC ground**
—
PWR
—
—
Note: I/T: Input type; O/T: Output type
OP: Optional by configuration option (CO) or register option
PWR: Power; CO: Configuration option; ST: Schmitt Trigger input
CMOS: CMOS output; NMOS: NMOS output
SCOM: Software controlled LCD COM; AN: Analog input pin
HXT: High frequency crystal oscillator
LXT: Low frequency crystal oscillator
*: VDD is the device power supply while AVDD is the ADC power supply. The AVDD pin is bonded
together internally with VDD.
**: VSS is the device ground pin while AVSS is the ADC ground pin. The AVSS pin is bonded together
internally with VSS.
As the Pin Description Summary table applies to the package type with the most pins, not all of the above
listed pins may be present on package types with smaller numbers of pins.
Rev. 1.30
12
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
HT66F30-1
Pin Name
Function
OP
I/T
O/T
PAWU
PAPU
Pin-Shared Mapping
ST
CMOS
—
PA0~PA7
Port A
PB0~PB5
Port B
PBPU
ST
CMOS
—
PC0~PC7
Port C
PCPU
ST
CMOS
—
AN0~AN7
ADC input
ACERL
AN
—
PA0~PA7
VREF
ADC reference input
ADCR1
AN
—
PB5
C0-, C1-
Comparator 0, 1 input
AN
—
PA3, PC3
C0+, C1+
Comparator 0, 1 input
AN
—
PA2, PC2
C0X, C1X
Comparator 0, 1 output
—
CMOS
PA0, PA5
TCK0, TCK1
TM0, TM1 input
—
ST
—
PA2, PA4
TP0_0, TP0_1
TM0 I/O
TMPC0
ST
CMOS
PA0, PC5
TP1A
TM1 I/O
TMPC0
ST
CMOS
PA1
TP1B_0, TP1B_1
TM1 I/O
TMPC0
ST
CMOS
PC0, PC1
INT0, INT1
Ext. interrupt 0, 1
—
ST
—
PA3, PA4
PINT
Peripheral interrupt
PRM0
ST
—
PC3 or PC4
PCK
Peripheral clock output
PRM0
—
CMOS
PC2 or PC5
SDI
SPI data input
PRM0
ST
—
PA6 or PC0
SDO
SPI data output
PRM0
—
CMOS
PA5 or PC1
CP0C
CP1C
SCS
SPI slave select
PRM0
ST
CMOS
PB5 or PC6
SCK
SPI serial clock
PRM0
ST
CMOS
PA7 or PC7
SCL
I2C clock
PRM0
ST
NMOS
PA7 or PC7
SDA
I C data
SCOM0~SCOM3
SCOM0~SCOM3
2
PRM0
ST
NMOS
PA6 or PC0
SCOMC
—
SCOM
PC0, PC1, PC6, PC7
OSC1
HXT/ERC pin
CO
HXT
—
PB1
OSC2
HXT pin
CO
—
HXT
PB2
XT1
LXT pin
CO
LXT
—
PB3
XT2
LXT pin
CO
—
LXT
PB4
RES
Reset input
CO
ST
—
PB0
VDD
Power supply *
—
PWR
—
—
AVDD
ADC power supply *
—
PWR
—
—
VSS
Ground **
—
PWR
—
—
AVSS
ADC ground **
—
PWR
—
—
Note: I/T: Input type; O/T: Output type
OP: Optional by configuration option (CO) or register option
PWR: Power; CO: Configuration option; ST: Schmitt Trigger input
CMOS: CMOS output; NMOS: NMOS output
SCOM: Software controlled LCD COM; AN: Analog input pin
HXT: High frequency crystal oscillator; LXT: Low frequency crystal oscillator
*: VDD is the device power supply while AVDD is the ADC power supply. The AVDD pin is bonded
together internally with VDD.
**: VSS is the device ground pin while AVSS is the ADC ground pin. The AVSS pin is bonded together
internally with VSS.
As the Pin Description Summary table applies to the package type with the most pins, not all of the above
listed pins may be present on package types with smaller numbers of pins.
Rev. 1.30
13
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
HT68F20-1
Pin Name
Function
OP
I/T
O/T
Pin-Shared Mapping
PAWU
PAPU
ST
CMOS
—
—
PA0~PA7
Port A
PB0~PB5
Port B
PBPU
ST
CMOS
PC0~PC3
Port C
PCPU
ST
CMOS
C0-, C1-
Comparator 0, 1 input
AN
—
PA3, PC3
C0+, C1+
Comparator 0, 1 input
C0X, C1X
Comparator 0, 1 output
TCK0, TCK1
TM0, TM1 input
TP0_0
—
CP0C
CP1C
AN
—
PA2, PC2
­—
CMOS
PA0, PA5
—
ST
—
PA2, PA4
TM0 I/O
TMPC0
ST
CMOS
TP1_0, TP1_1
TM1 I/O
TMPC0
ST
CMOS
PA1, PC0
INT0, INT1
Ext. Interrupt 0, 1
—
ST
—
PA3, PA4
PINT
Peripheral Interrupt
—
ST
—
PC3
PCK
Peripheral Clock output
—
—
CMOS
PC2
SDI
SPI Data input
—
ST
—
PA6
SDO
SPI Data output
—
—
CMOS
PA5
PA0
SCS
SPI Slave Select
—
ST
CMOS
PB5
SCK
SPI Serial Clock
—
ST
CMOS
PA7
SCL
I C Clock
—
ST
NMOS
PA7
SDA
I2C Data
—
ST
NMOS
PA6
SCOM0~SCOM3
SCOM0~SCOM3
SCOMC
—
SCOM
PC0, PC1, PC2, PC3
OSC1
HXT/ERC pin
CO
HXT
—
OSC2
HXT pin
CO
—
HXT
PB2
XT1
LXT pin
CO
LXT
—
PB3
XT2
LXT pin
CO
—
LXT
PB4
RES
Reset input
CO
ST
—
PB0
VDD
Power supply
—
PWR
—
—
VSS
Ground
—
PWR
—
—
2
PB1
Note: I/T: Input type
O/T: Output type
OP: Optional by configuration option (CO) or register option
PWR: Power
CO: Configuration option
ST: Schmitt Trigger input
CMOS: CMOS output
NMOS: NMOS output
SCOM: Software controlled LCD COM
AN: Analog input pin
HXT: High frequency crystal oscillator
LXT: Low frequency crystal oscillator
As the Pin Description Summary table applies to the package type with the most pins, not all of the above
listed pins may be present on package types with smaller numbers of pins.
Rev. 1.30
14
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
HT68F30-1
Pin Name
Function
OP
I/T
O/T
Pin-Shared Mapping
PAWU
PAPU
ST
CMOS
—
PA0~PA7
Port A
PB0~PB5
Port B
PBPU
ST
CMOS
—
PC0~PC7
Port C
PCPU
ST
CMOS
—
C0-, C1-
Comparator 0, 1 input
AN
—
PA3, PC3
C0+, C1+
Comparator 0, 1 input
AN
—
PA2, PC2
C0X, C1X
Comparator 0, 1 output
TCK0, TCK1
TM0, TM1 input
TP0_0, TP0_1
CP0C
CP1C
—
CMOS
PA0, PA5
—
ST
—
PA2, PA4
TM0 I/O
TMPC0
ST
CMOS
PA0, PC5
TP1A
TM1 I/O
TMPC0
ST
CMOS
PA1
TP1B_0, TP1B_1
TM1 I/O
TMPC0
ST
CMOS
PC0, PC1
INT0, INT1
Ext. interrupt 0, 1
—
ST
—
PA3, PA4
PINT
Peripheral interrupt
PRM0
ST
—
PC3 or PC4
PCK
Peripheral clock output
PRM0
—
CMOS
PC2 or PC5
SDI
SPI data input
PRM0
ST
—
PA6 or PC0
SDO
SPI data output
PRM0
—
CMOS
PA5 or PC1
SCS
SPI slave select
PRM0
ST
CMOS
PB5 or PC6
SCK
SPI serial clock
PRM0
ST
CMOS
PA7 or PC7
SCL
I C clock
PRM0
ST
NMOS
PA7 or PC7
SDA
I2C data
PRM0
ST
NMOS
PA6 or PC0
SCOM0~SCOM3
SCOM0~SCOM3
SCOMC
—
SCOM
PC0, PC1, PC6, PC7
2
OSC1
HXT/ERC pin
CO
HXT
—
PB1
OSC2
HXT pin
CO
—
HXT
PB2
XT1
LXT pin
CO
LXT
—
PB3
XT2
LXT pin
CO
—
LXT
PB4
PB0
RES
Reset input
CO
ST
—
VDD
Power supply
—
PWR
—
—
VSS
Ground
—
PWR
—
—
Note: I/T: Input type
O/T: Output type
OP: Optional by configuration option (CO) or register option
PWR: Power
CO: Configuration option
ST: Schmitt Trigger input
CMOS: CMOS output
NMOS: NMOS output
SCOM: Software controlled LCD COM
AN: Analog input pin
HXT: High frequency crystal oscillator
LXT: Low frequency crystal oscillator
As the Pin Description Summary table applies to the package type with the most pins, not all of the above
listed pins may be present on package types with smaller numbers of pins.
Rev. 1.30
15
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
Absolute Maximum Ratings
Supply Voltage.................................................................................................VSS−0.3V to VSS+6.0V
Input Voltage...................................................................................................VSS−0.3V to VDD+0.3V
Storage Temperature.....................................................................................................-50˚C to 125˚C
Operating Temperature...................................................................................................-40˚C to 85˚C
IOH Total.....................................................................................................................................-80mA
IOL Total...................................................................................................................................... 80mA
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
HT66F20-1/HT66F30-1
Ta=25˚C
Symbol
VDD
Parameter
Operating Voltage
(HXT, ERC, HIRC)
Test Conditions
—
3V
5V
IDD1
Operating Current, Normal Mode,
fSYS=fH (HXT, ERC, HIRC)
3V
5V
3V
5V
IDD2
Operating Current, Normal Mode,
fSYS=fH (HXT)
IDD3
Operating Current, Slow Mode,
fSYS=fL (LXT, LIRC)
3V
IIDLE0
IDLE0 Mode Standby Current
(LXT or LIRC on)
3V
5V
IIDLE1
IDLE1 Mode Standby Current
(HXT, ERC, HIRC)
5V
ISLEEP0
SLEEP0 Mode Standby Current
(LXT and LIRC off)
5V
ISLEEP1
SLEEP1 Mode Standby Current
(LXT or LIRC on)
5V
Rev. 1.30
Conditions
VDD
5V
5V
3V
3V
3V
Min.
Typ.
Max.
Unit
fSYS=8MHz
2.2
—
5.5
V
fSYS=12MHz
2.7
—
5.5
V
fSYS=20MHz
4.5
—
5.5
V
No load, fSYS=fH=4MHz,
ADC off, WDT enable
—
0.7
1.1
mA
—
1.8
2.7
mA
No load, fSYS=fH=8MHz,
ADC off, WDT enable
—
1.6
2.4
mA
—
3.3
5.0
mA
No load, fSYS=fH=12MHz,
ADC off, WDT enable
—
2.2
3.3
mA
—
5.0
7.5
mA
—
6.0
9.0
mA
No load, fSYS=fL, ADC off,
WDT enable
—
10
20
μA
—
30
50
μA
No load, ADC off,
WDT enable
—
1.5
3.0
μA
—
3.0
6.0
μA
No load, ADC off,
WDT enable, fSYS=12MHz on
—
0.55
0.83
mA
—
1.30
2.00
mA
No load, ADC off,
WDT disable
—
—
1
μA
—
—
2
μA
No load, ADC off,
WDT enable
—
1.5
3.0
μA
—
2.5
5.0
μA
No load, fSYS=fH=20MHz,
ADC off, WDT enable
16
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
Symbol
Parameter
Test Conditions
VDD
Conditions
Min.
Typ.
Max.
Unit
VIL1
Input Low Voltage for I/O Ports or
Input Pins except RES pin
—
—
0
—
0.3VDD
V
VIH1
Input High Voltage for I/O Ports or
Input Pins except RES pin
—
—
0.7VDD
—
VDD
V
VIL2
Input Low Voltage (RES)
—
—
0
—
0.4VDD
V
VIH2
Input High Voltage (RES)
—
—
VLVR
VLVD
ILV
LVR Voltage Level
LVD Voltage Level
Additional Power Consumption if
LVR and LVD is Used
VOL
Output Low Voltage I/O Port
VOH
Output High Voltage I/O Port
RPH
Pull-high Resistance for I/O Ports
ISCOM
SCOM Operating Current
—
—
0.9VDD
—
VDD
V
LVR Enable, 2.10V option
-5%
2.10
+5%
V
LVR Enable, 2.55V option
-5%
2.55
+5%
V
LVR Enable, 3.15V option
-5%
3.15
+5%
V
LVR Enable, 4.20V option
-5%
4.20
+5%
V
LVDEN=1, VLVD=2.0V
-5%
2.00
+5%
V
LVDEN=1, VLVD=2.2V
-5%
2.20
+5%
V
LVDEN=1, VLVD=2.4V
-5%
2.40
+5%
V
LVDEN=1, VLVD=2.7V
-5%
2.70
+5%
V
LVDEN=1, VLVD=3.0V
-5%
3.00
+5%
V
LVDEN=1, VLVD=3.3V
-5%
3.30
+5%
V
LVDEN=1, VLVD=3.6V
-5%
3.60
+5%
V
LVDEN=1, VLVD=4.4V
-5%
4.40
+5%
V
LVR enable, LVDEN=0
—
60
90
μA
—
LVR disable, LVDEN=1
—
75
115
μA
LVR enable, LVDEN=1
—
90
135
μA
3V
IOL=9mA
—
—
0.3
V
5V
IOL=20mA
—
—
0.5
V
3V
IOH=-3.2mA
2.7
—
—
V
5V
IOH=-7.4mA
4.5
—
—
V
3V
20
60
100
kΩ
10
30
50
kΩ
SCOMC, ISEL[1:0]=00
17.5
25.0
32.5
μA
SCOMC, ISEL[1:0]=01
35
50
65
μA
SCOMC, ISEL[1:0]=10
70
100
130
μA
SCOMC, ISEL[1:0]=11
140
200
260
μA
—
5V
5V
VSCOM
VDD/2 Voltage for LCD COM
5V
0.475
0.500
0.525
VDD
V125
1.25V Reference with Buffer Voltage
—
—
-3%
1.25
+3%
V
I125
Additional Power Consumption if
1.25V Reference with Buffer is used
—
—
—
200
300
μA
Rev. 1.30
No load
17
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
HT68F20-1/HT68F30-1
Ta=25˚C
Symbol
VDD
Parameter
Operating Voltage
(HXT, ERC, HIRC)
Test Conditions
—
3V
5V
IDD1
Operating Current,
Normal Mode, fSYS=fH
(HXT, ERC, HIRC)
3V
5V
3V
5V
IDD2
Operating Current,
Normal Mode, fSYS=fH (HXT)
IDD3
Operating Current, Slow Mode,
fSYS=fL (LXT, LIRC)
IIDLE0
IDLE0 Mode Standby Current
(LXT or LIRC on)
5V
IIDLE1
IDLE1 Mode Standby Current
(HXT, ERC, HIRC)
5V
ISLEEP0
SLEEP0 Mode Standby Current
(LXT and LIRC off)
3V
ISLEEP1
SLEEP1 Mode Standby Current
(LXT or LIRC on)
3V
VIL1
Input Low Voltage for I/O Ports or
Input Pins except RES pin
—
VIH1
Input High Voltage for I/O Ports
or Input Pins except RES pin
VIL2
VIH2
VLVR
VLVD
Rev. 1.30
Min.
Typ.
Max.
Unit
fSYS=8MHz
2.2
—
5.5
V
fSYS=12MHz
2.7
—
5.5
V
fSYS=20MHz
4.5
—
5.5
V
No load, fSYS=fH=4MHz,
WDT enable
—
0.7
1.1
mA
—
1.8
2.7
mA
No load, fSYS=fH=8MHz,
WDT enable
—
1.6
2.4
mA
—
3.3
5.0
mA
Conditions
VDD
5V
3V
5V
3V
3V
5V
No load, fSYS=fH=12MHz,
WDT enable
No load, fSYS=fH=20MHz,
WDT enable
No load, fSYS=fL,
WDT enable
No load, WDT enable
No load, WDT enable,
fSYS=12MHz on
No load, WDT disable
—
2.2
3.3
mA
—
5.0
7.5
mA
—
6.0
9.0
mA
—
10
20
μA
—
30
50
μA
—
1.5
3.0
mA
—
3.0
6.0
mA
—
0.55
0.83
mA
—
1.30
2.00
mA
—
—
1
μA
—
—
2
μA
—
1.5
3.0
μA
—
2.5
5.0
μA
—
0
—
0.3VDD
V
—
—
0.7VDD
—
VDD
V
Input Low Voltage (RES)
—
—
0
—
0.4VDD
V
Input High Voltage (RES)
—
—
LVR Voltage Level
LVD Voltage Level
5V
—
—
No load, WDT enable
0.9VDD
—
VDD
V
LVR Enable, 2.10V option
-5%
2.10
+5%
V
LVR Enable, 2.55V option
-5%
2.55
+5%
V
LVR Enable, 3.15V option
-5%
3.15
+5%
V
LVR Enable, 4.20V option
-5%
4.20
+5%
V
LVDEN=1, VLVD=2.0V
-5%
2.00
+5%
V
LVDEN=1, VLVD=2.2V
-5%
2.20
+5%
V
LVDEN=1, VLVD=2.4V
-5%
2.40
+5%
V
LVDEN=1, VLVD=2.7V
-5%
2.70
+5%
V
LVDEN=1, VLVD=3.0V
-5%
3.00
+5%
V
LVDEN=1, VLVD=3.3V
-5%
3.30
+5%
V
LVDEN=1, VLVD=3.6V
-5%
3.60
+5%
V
LVDEN=1, VLVD=4.4V
-5%
4.40
+5%
V
18
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
Symbol
Test Conditions
Parameter
Additional Power Consumption if
LVR and LVD is used
ILV
Output Low Voltage I/O Port
VOH
Output High Voltage I/O Port
RPH
Pull-high Resistance for I/O Ports
VSCOM
SCOM Operating Current
VDD/2 Voltage for LCD COM
Typ.
LVR enable, LVDEN=0
—
LVR disable, LVDEN=1
—
LVR enable, LVDEN=1
3V
5V
3V
5V
—
VOL
ISCOM
Min.
Max.
Unit
60
90
μA
75
115
μA
—
90
135
μA
IOL=9mA
—
—
0.3
V
IOL=20mA
—
—
0.5
V
IOH=-3.2mA
2.7
—
—
V
IOH=-7.4mA
4.5
—
—
V
20
60
100
kΩ
10
30
50
kΩ
SCOMC, ISEL[1:0]=00
17.5
25.0
32.5
μA
SCOMC, ISEL[1:0]=01
35
50
65
μA
Conditions
VDD
3V
—
5V
5V
5V
SCOMC, ISEL[1:0]=10
70
100
130
μA
SCOMC, ISEL[1:0]=11
140
200
260
μA
0.475
0.500
0.525
VDD
No load
A.C. Characteristics
HT66F20-1/HT66F30-1
Ta=25˚C
Symbol
fCPU
fSYS
Parameter
Operating Clock
System Clock (HXT)
Test Conditions
—
—
Rev. 1.30
System Clock (HIRC)
Typ.
Max.
Unit
2.2V~5.5V
DC
—
8
MHz
2.7V~5.5V
DC
—
12
MHz
4.5V~5.5V
DC
—
20
MHz
2.2V~5.5V
0.4
—
8
MHz
2.7V~5.5V
0.4
—
12
MHz
4.5V~5.5V
0.4
—
20
MHz
3V/5V
Ta=25˚C
-2%
4
+2%
MHz
3V/5V
Ta=25˚C
-2%
8
+2%
MHz
5V
fHIRC
Min.
Conditions
VDD
Ta=25˚C
-2%
12
+2%
MHz
3V/5V
Ta=0~70˚C
-5%
4
+5%
MHz
3V/5V
Ta=0~70˚C
-4%
8
+4%
MHz
5V
Ta=0~70˚C
-5%
12
+3%
MHz
2.2V~3.6V Ta=0~70˚C
-7%
4
+7%
MHz
3.0V~5.5V Ta=0~70˚C
-5%
4
+9%
MHz
2.2V~3.6V Ta=0~70˚C
-6%
8
+4%
MHz
3.0V~5.5V Ta=0~70˚C
-4%
8
+9%
MHz
3.0V~5.5V Ta=0~70˚C
-6%
12
+7%
MHz
2.2V~3.6V Ta=-40˚C~85˚C
-12%
4
+8%
MHz
3.0V~5.5V Ta=-40˚C~85˚C
-10%
4
+9%
MHz
2.2V~3.6V Ta=-40˚C~85˚C
-15%
8
+4%
MHz
3.0V~5.5V Ta=-40˚C~85˚C
-8%
8
+9%
MHz
3.0V~5.5V Ta=-40˚C~85˚C
-12%
12
+7%
MHz
19
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
Symbol
fERC
fLXT
Parameter
System Clock (ERC)
System Clock (LXT)
Test Conditions
Min.
Typ.
Max.
Unit
Ta=25˚C, R=120kΩ*
-2%
8
+2%
MHz
Ta=0~70˚C, R=120kΩ*
-5%
8
+6%
MHz
Ta=-40˚C~85˚C, R=120kΩ*
-7%
8
+9%
MHz
3.0V~5.5V Ta=-40˚C~85˚C, R=120kΩ*
-9%
8
+10% MHz
2.2V~5.5V Ta=-40˚C~85˚C, R=120kΩ*
-15%
8
+10% MHz
VDD
Conditions
5V
5V
5V
—
5V
—
Ta=25˚C
—
32.768
—
kHz
-10%
32
+10%
kHz
fLIRC
System Clock (LIRC)
-50%
32
+60%
kHz
fTIMER
Timer Input Pin Frequency
—
—
—
—
1
fSYS
2.2V~5.5V Ta=-40˚C~85˚C
tRES
External Reset Low Pulse Width
—
—
1
—
—
μs
tINT
Interrupt Pulse Width
—
—
1
—
—
tSYS
tLVR
Low Voltage Width to Reset
—
—
120
240
480
μs
tLVD
Low Voltage Width to Interrupt
—
—
20
45
90
μs
tLVDS
LVDO stable time
—
—
15
—
—
μs
tBGS
VBG Turn on Stable Time
—
—
200
—
—
μs
tEERD
EEPROM Read Time
—
—
—
45
90
μs
tEEWR
EEPROM Write Time
—
—
ms
tSST
System Start-up Timer Period
(Wake-up from HALT)
—
—
2
4
fSYS=HXT or LXT
—
1024
—
fSYS=ERC or HIRC
—
15~16
—
fSYS=LIRC OSC
—
1~2
—
tSYS
Note: 1. tSYS=1/fSYS
2. * For fERC, as the resistor tolerance will influence the frequency a precision resistor is recommended.
3. To maintain the accuracy of the internal HIRC oscillator frequency, a 0.1μF decoupling capacitor should
be connected between VDD and VSS and located as close to the device as possible.
Rev. 1.30
20
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
HT68F20-1/HT68F30-1
Symbol
fCPU
fSYS
fHIRC
fERC
fLXT
Parameter
Operating Clock
System Clock (HXT)
System Clock (HIRC)
System Clock (ERC)
System Clock (LXT)
Ta=25˚C
Test Conditions
Min.
Typ.
Max.
Unit
2.2V~5.5V
DC
2.7V~5.5V
DC
—
8
MHz
—
12
4.5V~5.5V
MHz
DC
—
20
MHz
2.2V~5.5V
0.4
—
8
MHz
2.7V~5.5V
0.4
—
12
MHz
4.5V~5.5V
0.4
—
20
MHz
3V/5V
Ta=25˚C
-2%
4
+2%
MHz
3V/5V
Ta=25˚C
-2%
8
+2%
MHz
5V
Ta=25˚C
-2%
12
+2%
MHz
3V/5V
Ta=0~70˚C
-5%
4
+5%
MHz
3V/5V
Ta=0~70˚C
-4%
8
+4%
MHz
5V
Ta=0~70˚C
-5%
12
+3%
MHz
2.2V~3.6V Ta=0~70˚C
-7%
4
+7%
MHz
3.0V~5.5V Ta=0~70˚C
-5%
4
+9%
MHz
2.2V~3.6V Ta=0~70˚C
-6%
8
+4%
MHz
VDD
—
—
Conditions
3.0V~5.5V Ta=0~70˚C
-4%
8
+9%
MHz
3.0V~5.5V Ta=0~70˚C
-6%
12
+7%
MHz
2.2V~3.6V Ta=-40˚C~85˚C
-12%
4
+8%
MHz
3.0V~5.5V Ta=-40˚C~85˚C
-10%
4
+9%
MHz
2.2V~3.6V Ta=-40˚C~85˚C
-15%
8
+4%
MHz
3.0V~5.5V Ta=-40˚C~85˚C
-8%
8
+9%
MHz
3.0V~5.5V Ta=-40˚C~85˚C
-12%
12
+7%
MHz
5V
Ta=25˚C, R=120kΩ*
-2%
8
+2%
MHz
5V
Ta=0~70˚C, R=120kΩ*
-5%
8
+6%
MHz
5V
Ta=-40˚C~85˚C, R=120kΩ*
-7%
8
+9%
MHz
3.0V~5.5V Ta=-40˚C~85˚C, R=120kΩ*
-9%
8
+10%
MHz
2.2V~5.5V Ta=-40˚C~85˚C, R=120kΩ*
-15%
8
+10%
MHz
—
32.768
—
kHz
-10%
32
+10%
kHz
-50%
32
+60%
kHz
fSYS
—
5V
—
Ta=25˚C
fLIRC
System Clock (LIRC)
fTIMER
Timer Input Pin Frequency
—
—
—
—
1
tRES
External Reset Low Pulse Width
—
—
1
—
—
μs
tINT
Interrupt Pulse Width
—
—
1
—
—
tSYS
2.2V~5.5V Ta=-40˚C~85˚C
tLVR
Low Voltage Width to Reset
—
—
120
240
480
μs
tLVD
Low Voltage Width to Interrupt
—
—
20
45
90
μs
tLVDS
LVDO stable time
—
—
15
—
—
μs
tBGS
VBG Turn on Stable Time
—
—
200
—
—
μs
tEERD
EEPROM Read Time
—
—
—
45
90
μs
tEEWR
EEPROM Write Time
—
—
—
2
4
ms
System Start-up Timer Period
(Wake-up from HALT)
—
tSST
—
fSYS=HXT or LXT
—
1024
fSYS=ERC or HIRC
—
15~16
—
fSYS=LIRC OSC
—
1~2
—
tSYS
Note: 1. tSYS=1/fSYS
2. * For fERC, as the resistor tolerance will influence the frequency a precision resistor is recommended.
3. To maintain the accuracy of the internal HIRC oscillator frequency, a 0.1μF decoupling capacitor should
be connected between VDD and VSS and located as close to the device as possible.
Rev. 1.30
21
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
A/D Converter Characteristics
HT66F20-1/HT66F30-1
Ta=25˚C
Symbol
Parameter
Test Conditions
VDD
Condition
Min.
Typ.
Max.
Unit
AVDD
A/D Converter Operating Voltage
—
—
2.7
—
5.5
V
VADI
A/D Converter Input Voltage
—
—
0
—
VREF
V
VREF
A/D Converter Reference Voltage
—
2
—
AVDD
V
DNL
Differential non-linearity
5V
tADCK=1.0μs
—
±1
+2
LSB
INL
Integral non-linearity
5V
tADCK=1.0μs
—
±2
+4
LSB
IADC
Additional Power Consumption if A/D
Converter is used
3V
No load (tADCK=0.5μs )
—
0.90
1.35
mA
5V
No load (tADCK=0.5μs )
—
1.20
1.80
mA
tADCK
A/D Converter Clock Period
—
0.5
—
10
μs
tADC
A/D Conversion Time
(Include Sample and Hold Time)
—
—
16
—
tADCK
tADS
A/D Converter Sampling Time
—
—
—
4
—
tADCK
tON2ST
A/D Converter On-to-Start Time
—
—
2
—
—
μs
—
—
12 bit A/D Converter
Comparator Electrical Characteristics
Ta=25˚C
Symbol
VCMP
Parameter
Comparator operating voltage
ICMP
Comparator operating current
Test Conditions
VDD
Condition
Min. Typ.
Max.
Unit
—
—
2.2
—
5.5
V
3V
—
—
37
56
μA
5V
—
—
130
200
μA
—
-10
—
+10
mV
20
40
60
mV
VCMPOS
Comparator input offset voltage
—
VHYS
Hysteresis width
—
VCM
Comparator common mode voltage range —
—
VSS
—
VDD-1.4V
V
AOL
Comparator open loop gain
—
60
80
—
dB
tPD
Comparator response time
—
370
560
ns
—
3V
5V
With 100mV overdrive(Note)
Note: Measured with comparator one input pin at VCM=(VDD-1.4)/2 while the other pin input transition from VSS to
(VCM+100mV) or from VDD to (VCM-100mV).
Rev. 1.30
22
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
Power on Reset Electrical Characteristics
Ta=25˚C
Symbol
Test Conditions
Parameter
VDD
Condition
Min.
Typ.
Max.
Unit
VPOR
VDD Start Voltage to ensure Power-on Reset
—
—
—
—
100
mV
RRVDD
VDD Rise Rate to ensure Power-on Reset
—
—
0.035
—
—
V/ms
tPOR
Minimum Time for VDD to remain at VPOR to
ensure Power-on Reset
—
—
1
—
—
ms
System Architecture
A key factor in the high-performance features of the Holtek range of microcontrollers is attributed
to their internal system architecture. The range of devices take advantage of the usual features found
within RISC microcontrollers providing increased speed of operation and enhanced performance.
The pipelining scheme is implemented in such a way that instruction fetching and instruction
execution are overlapped, hence instructions are effectively executed in one cycle, with the
exception of branch or call instructions. An 8-bit wide ALU is used in practically all instruction set
operations, which carries out arithmetic operations, logic operations, rotation, increment, decrement,
branch decisions, etc. The internal data path is simplified by moving data through the Accumulator
and the ALU. Certain internal registers are implemented in the Data Memory and can be directly
or indirectly addressed. The simple addressing methods of these registers along with additional
architectural features ensure that a minimum of external components is required to provide a
functional I/O and A/D control system with maximum reliability and flexibility. This makes these
devices suitable for low-cost, high-volume production for controller applications.
Clocking and Pipelining
The main system clock, derived from either a HXT, LXT, HIRC, LIRC or ERC oscillator is
subdivided into four internally generated non-overlapping clocks, T1~T4. The Program Counter is
incremented at the beginning of the T1 clock during which time a new instruction is fetched. The
remaining T2~T4 clocks carry out the decoding and execution functions. In this way, one T1~T4
clock cycle forms one instruction cycle. Although the fetching and execution of instructions takes
place in consecutive instruction cycles, the pipelining structure of the microcontroller ensures that
instructions are effectively executed in one instruction cycle. The exception to this are instructions
where the contents of the Program Counter are changed, such as subroutine calls or jumps, in which
case the instruction will take one more instruction cycle to execute.
For instructions involving branches, such as jump or call instructions, two machine cycles are
required to complete instruction execution. An extra cycle is required as the program takes one
cycle to first obtain the actual jump or call address and then another cycle to actually execute the
branch. The requirement for this extra cycle should be taken into account by programmers in timing
sensitive applications.
Rev. 1.30
23
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM


   
   
System Clocking and Pipelining
  
    
 Instruction Fetching
Program Counter
During program execution, the Program Counter is used to keep track of the address of the
next instruction to be executed. It is automatically incremented by one each time an instruction
is executed except for instructions, such as “JMP” or “CALL” that demand a jump to a
non-consecutive Program Memory address. Only the lower 8 bits, known as the Program Counter
Low Register, are directly addressable by the application program.
When executing instructions requiring jumps to non-consecutive addresses such as a jump
instruction, a subroutine call, interrupt or reset, etc., the microcontroller manages program control
by loading the required address into the Program Counter. For conditional skip instructions, once
the condition has been met, the next instruction, which has already been fetched during the present
instruction execution, is discarded and a dummy cycle takes its place while the correct instruction is
obtained.
Device
Program Counter
Program Counter High Byte
PCL Register
HT66F20-1/HT68F20-1
PC9~PC8
PCL7~PCL0
HT66F30-1/HT68F30-1
PC10~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
Rev. 1.30
24
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
needed to pre-fetch.
Stack
This is a special part of the memory which is used to save the contents of the Program Counter only.
The stack has four levels and is neither part of the data nor part of the program space, and is neither
readable nor writeable. The activated level is indexed by the Stack Pointer, and is neither readable
nor writeable. At a subroutine call or interrupt acknowledge signal, the contents of the Program
Counter are pushed onto the stack. At the end of a subroutine or an interrupt routine, signaled by
a return instruction, RET or RETI, the Program Counter is restored to its previous value from the
stack. After a device reset, the Stack Pointer will point to the top of the stack.
If the stack is full and an enabled interrupt takes place, the interrupt request flag will be recorded but
the acknowledge signal will be inhibited. When the Stack Pointer is decremented, by RET or RETI,
the interrupt will be serviced. This feature prevents stack overflow allowing the programmer to use
the structure more easily. However, when the stack is full, a CALL subroutine instruction can still
be executed which will result in a stack overflow. Precautions should be taken to avoid such cases
which might cause unpredictable program branching.
If the stack is overflow, the first Program Counter save in the stack will be lost.
P ro g ra m
T o p o f S ta c k
S ta c k L e v e l 1
S ta c k L e v e l 2
S ta c k
P o in te r
B o tto m
C o u n te r
S ta c k L e v e l 3
o f S ta c k
S ta c k L e v e l 4
P ro g ra m
M e m o ry
Arithmetic and Logic Unit – ALU
The arithmetic-logic unit or ALU is a critical area of the microcontroller that carries out arithmetic
and logic operations of the instruction set. Connected to the main microcontroller data bus, the ALU
receives related instruction codes and performs the required arithmetic or logical operations after
which the result will be placed in the specified register. As these ALU calculation or operations may
result in carry, borrow or other status changes, the status register will be correspondingly updated to
reflect these changes. The ALU supports the following functions:
• Arithmetic operations: ADD, ADDM, ADC, ADCM, SUB, SUBM, SBC, SBCM, DAA
• Logic operations: AND, OR, XOR, ANDM, ORM, XORM, CPL, CPLA
• Rotation RRA, RR, RRCA, RRC, RLA, RL, RLCA, RLC
• Increment and Decrement INCA, INC, DECA, DEC
• Branch decision, JMP, SZ, SZA, SNZ, SIZ, SDZ, SIZA, SDZA, CALL, RET, RETI
Rev. 1.30
25
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
Flash Program Memory
The Program Memory is the location where the user code or program is stored. For these devices
series the Program Memory are Flash type, which means it can be programmed and re-programmed
a large number of times, allowing the user the convenience of code modification on the same
device. By using the appropriate programming tools, these Flash devices offer users the flexibility to
conveniently debug and develop their applications while also offering a means of field programming
and updating.
Structure
The Program Memory has a capacity of 1K×16 bits to 2K×16 bits. The Program Memory is
addressed by the Program Counter and also contains data, table information and interrupt entries.
Table data, which can be setup in any location within the Program Memory, is addressed by a
separate table pointer register.
Device
Capacity
HT66F20-1 / HT68F20-1
1K×16
HT66F30-1 / HT68F30-1
2K×16
Special Vectors
Within the Program Memory, certain locations are reserved for the reset and interrupts. The location
000H is reserved for use by these devices reset for program initialisation. After a device reset is
initiated, the program will jump to this location and begin execution.
Program Memory Structure
Rev. 1.30
26
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
Look-up Table
Any location within the Program Memory can be defined as a look-up table where programmers can
store fixed data. To use the look-up table, the table pointer must first be setup by placing the address
of the look up data to be retrieved in the table pointer register, TBLP and TBHP. These registers
define the total address of the look-up table.
After setting up the table pointer, the table data can be retrieved from the Program Memory using
the "TABRD [m]" or "TABRDL [m]" instructions, respectively. When the instruction is executed,
the lower order table byte from the Program Memory will be transferred to the user defined
Data Memory register [m] as specified in the instruction. The higher order table data byte from
the Program Memory will be transferred to the TBLH special register. Any unused bits in this
transferred higher order byte will be read as “0”.
The accompanying diagram illustrates the addressing data flow of the look-up table.
A d d re s s
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
D a ta
1 6 b its
R e g is te r T B L H
U s e r S e le c te d
R e g is te r
H ig h B y te
L o w B y te
Table Program Example
The following example shows how the table pointer and table data is defined and retrieved from the
microcontroller. This example uses raw table data located in the Program Memory which is stored
there using the ORG statement. The value at this ORG statement is "700H" which refers to the start
address of the last page within the 2K Program Memory of the HT6xF30-1. 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 "706H" or 6 locations after the start of the last page.
Note that the value for the table pointer is referenced to the first address of the present page if the
"TABRD [m]" instruction is being used. The high byte of the table data which in this case is equal
to zero will be transferred to the TBLH register automatically when the "TABRD [m]" instruction is
executed.
Because the TBLH register is a read-only register and cannot be restored, care should be taken
to ensure its protection if both the main routine and Interrupt Service Routine use table read
instructions. If using the table read instructions, the Interrupt Service Routines may change the
value of the TBLH and subsequently cause errors if used again by the main routine. As a rule it is
recommended that simultaneous use of the table read instructions should be avoided. However, in
situations where simultaneous use cannot be avoided, the interrupts should be disabled prior to the
execution of any main routine table-read instructions. Note that all table related instructions require
two instruction cycles to complete their operation.
Rev. 1.30
27
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
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 present page
mov a, 07h; initialise high table pointer
mov tbhp, a
:
:
tabrdl tempreg1 ; transfers value in table referenced by table pointer
; data at program memory address “706H” transferred to
; tempreg1 and TBLH
dec tblp ; reduce value of table pointer by one
tabrdl tempreg2 ; transfers value in table referenced by table pointer
; data at program memory address “705H” transferred to
; tempreg2 and TBLH in this example the data “1AH” is
; transferred to tempreg1 and data “0FH” to register tempreg2
:
:
org 700h; sets initial address of program memory
dc 00Ah, 00Bh, 00Ch, 00Dh, 00Eh, 00Fh, 01Ah, 01Bh
:
:
In Circuit Programming
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 5-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 sup plied with the latest program releases without removal and
re-insertion of the device.
MCU Programming Pins
PA0
Function
Serial Data Input/Output
PA2
Serial Clock
RES
Device Reset
VDD
Power Supply
VSS
Ground
The Program Memory and EEPROM data memory can both be programmed serially in-circuit using
this 5-wire interface. Data is downloaded and uploaded serially on a single pin with an additional
line for the clock. Two ad ditional lines are required for the power supply and one line for the reset.
The technical details regarding the incircuit programming of the device is beyond the scope of this
document and will be supplied in supple mentary literature.
Rev. 1.30
28
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
During the programming process the RES pin will be held low by the programmer disabling the
normal operation of the microcontroller and taking control of the PA0 and PA2 I/O 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
R E S
R E S
D A T A
P r o g r a m m in g
P in s
D A T A
C L K
C L K
W r ite r _ V S S
V S 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 1kΩ or the capacitance of * must be less than 1nF.
Programmer Pin
MCU Pins
RES
PB0
DATA
PA0
CLK
PA2
Programmer and MCU Pins
Data Memory
The Data Memory is a volatile area of 8-bit wide RAM internal memory and is the location where
temporary information is stored.
Structure
Divided into two sections, the first of these is an area of RAM, known as the Special Function Data
Memory. Here are located registers which are necessary for correct operation of the device. Many
of these registers can be read from and written to directly under program control, however, some
remain protected from user manipulation.
The second area of Data Memory is known as the General Purpose Data Memory, which is reserved
for general purpose use. All locations within this area are read and write accessible under program
control. The Special Purpose Data Memory registers are accessible in all banks, with the exception
of the EEC register at address 40H, which is only accessible in Bank 1. Switching between the
different Data Memory banks is achieved by setting the Bank Pointer to the correct value. The start
address of the Data Memory for all devices is the address 00H.
Rev. 1.30
29
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
HT66F20-1/HT68F20-1
00H
Special Purpose
Data Memory
EEC at 40H in bank 1
5FH
60H
General Purpose
Data Memory
9FH
HT66F30-1/HT68F30-1
00H
Special Purpose
Data Memory
EEC at 40H in bank 1
5FH
60H
General Purpose
Data Memory
BFH
Data Memory Structure
Rev. 1.30
30
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
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HT66F20-1 Special Purpose Data Memory
Rev. 1.30
31
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
   
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HT66F30-1 Special Purpose Data Memory
Rev. 1.30
32
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
   
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HT68F20-1 Special Purpose Data Memory
Rev. 1.30
33
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
   
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HT68F30-1 Special Purpose Data Memory
Rev. 1.30
34
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
Special Function Register Description
Most of the Special Function Register details will be described in the relevant functional section,
however several registers require a separate description in this section.
Indirect Addressing Registers – IAR0, IAR1
The Indirect Addressing Registers, IAR0 and IAR1, although having their locations in normal RAM
register space, do not actually physically exist as normal registers. The method of indirect addressing
for RAM data manipulation uses these Indirect Addressing Registers and Memory Pointers, in
contrast to direct memory addressing, where the actual memory address is specified. Actions on the
IAR0 and IAR1 registers will result in no actual read or write operation to these registers but rather
to the memory location specified by their corresponding Memory Pointers, MP0 or MP1. Acting as a
pair, IAR0 and MP0 can together access data from Bank 0 while the IAR1 and MP1 register pair can
access data from any bank. As the Indirect Addressing Registers are not physically implemented,
reading the Indirect Addressing Registers indirectly will return a result of “00H” and writing to the
registers indirectly will result in no operation.
Memory Pointers – MP0, MP1
Two Memory Pointers, known as MP0 and MP1 are provided. These Memory Pointers are
physically implemented in the Data Memory and can be manipulated in the same way as normal
registers providing a convenient way with which to address and track data. When any operation to
the relevant Indirect Addressing Registers is carried out, the actual address that the microcontroller
is directed to, is the address specified by the related Memory Pointer. MP0, together with Indirect
Addressing Register, IAR0, are used to access data from Bank 0, while MP1 and IAR1 are used to
access data from all banks according to BP register. Direct Addressing can only be used with Bank 0,
all other Banks must be addressed indirectly using MP1 and IAR1.
The following example shows how to clear a section of four Data Memory locations already defined
as locations adres1 to adres4.
Indirect Addressing Program Example
data .section data
adres1 db ?
adres2 db ?
adres3 db ?
adres4 db ?
block db ?
code .section at 0 code
org00h
start:
mov a,04h;
mov block,a
mov a,offset adres1 ;
mov mp0,a ;
loop:
clr IAR0 ;
inc mp0;
sdz block ;
jmp loop
continue:
setup size of block
Accumulator loaded with first RAM address
setup memory pointer with first RAM address
clear the data at address defined by MP0
increment memory pointer
check if last memory location has been cleared
The important point to note here is that in the example shown above, no reference is made to specific
RAM addresses.
Rev. 1.30
35
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
Bank Pointer – BP
The Data Memory is divided into two banks. Selecting the Data Memory area is achieved using the
Bank Pointer. Bit 0 of the Bank Pointer is used to select Data Memory Banks 0 or 1.
The Data Memory is initialised to Bank 0 after a reset, except for a WDT time-out reset in the
Power Down Mode, in which case, the Data Memory bank remains unaffected. Directly addressing
the Data Memory will always result in Bank 0 being accessed irrespective of the value of the
Bank Pointer. Accessing data from banks other than Bank 0 must be implemented using Indirect
addressing.
As both the Program Memory and Data Memory share the same Bank Pointer Register, care must be
taken during programming.
• HT66F30-1/HT68F30-1
Bit
7
6
5
4
3
2
1
0
Name
—
—
—
—
—
—
—
DMBP0
R/W
—
—
—
—
—
—
—
R/W
POR
—
—
—
—
—
—
—
0
Bit 7~1
Unimplemented, read as “0”
Bit 0DMBP0: Select Data Memory Banks
0: Bank 0
1: Bank 1
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.
Rev. 1.30
36
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
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 zero flag (Z), carry flag (C), auxiliary carry flag (AC), overflow flag
(OV), power down flag (PDF), and watchdog time-out flag (TO). These arithmetic/logical operation
and system management flags are used to record the status and operation of the microcontroller.
With the exception of the TO and PDF flags, bits in the status register can be altered by instructions
like most other registers. Any data written into the status register will not change the TO or PDF flag.
In addition, operations related to the status register may give different results due to the different
instruction operations. The TO flag can be affected only by a system power-up, a WDT time-out or
by executing the "CLR WDT" or "HALT" instruction. The PDF flag is affected only by executing
the "HALT" or "CLR WDT" instruction or during a system power-up.
The Z, OV, AC and C flags generally reflect the status of the latest operations.
• C is set if an operation results in a carry during an addition operation or if a borrow does not take
place during a subtraction operation; otherwise C is cleared. C is also affected by a rotate through
carry instruction.
• AC is set if an operation results in a carry out of the low nibbles in addition, or no borrow from
the high nibble into the low nibble in subtraction; otherwise AC is cleared.
• Z is set if the result of an arithmetic or logical operation is zero; otherwise Z is cleared.
• OV is set if an operation results in a carry into the highest-order bit but not a carry out of the
highest-order bit, or vice versa; otherwise OV is cleared.
• PDF is cleared by a system power-up or executing the “CLR WDT” instruction. PDF is set by
executing the “HALT” instruction.
• TO is cleared by a system power-up or executing the “CLR WDT” or “HALT” instruction. TO is
set by a WDT time-out.
In addition, on entering an interrupt sequence or executing a subroutine call, the status register will
not be pushed onto the stack automatically. If the contents of the status registers are important and if
the subroutine can corrupt the status register, precautions must be taken to correctly save it.
Rev. 1.30
37
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
STATUS Register
Bit
7
6
5
4
3
2
1
0
Name
—
—
TO
PDF
OV
Z
AC
C
R/W
—
—
R
R
R/W
R/W
R/W
R/W
POR
—
—
0
0
x
x
x
x
" x" unknown
Bit 7, 6
Unimplemented, read as “0”
Bit 5TO: Watchdog Time-Out flag
0: After power up or executing the “CLR WDT” or “HALT” instruction
1: A watchdog time-out occurred.
Bit 4PDF: Power down flag
0: After power up or executing the “CLR WDT” instruction
1: By executing the “HALT” instruction
Bit 3OV: Overflow flag
0: No overflow
1: An operation results in a carry into the highest-order bit but not a carry out of the
highest-order bit or vice versa.
Bit 2Z: Zero flag
0: The result of an arithmetic or logical operation is not zero
1: The result of an arithmetic or logical operation is zero
Bit 1AC: Auxiliary flag
0: No auxiliary carry
1: An operation results in a carry out of the low nibbles in addition, or no borrow
from the high nibble into the low nibble in subtraction
Bit 0C: Carry flag
0: No carry-out
1: An operation results in a carry during an addition operation or if a borrow does
not take place during a subtraction operation
C is also affected by a rotate through carry instruction.
EEPROM Data Memory
All devices contain 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 up to 64×8 bits. 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 data
register in Bank 0 and a single control register in Bank 1.
Rev. 1.30
Device
Capacity
Address
HT66F20-1/HT68F20-1
32×8
00H~1FH
HT66F30-1/HT68F30-1
64×8
00H~3FH
38
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
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 Bank 0, they can be directly accessed in the same was as any other
Special Function Register. The EEC register however, being located in Bank1, cannot be addressed
directly and can only be read from or written to indirectly using the MP1 Memory Pointer and
Indirect Addressing Register, IAR1. Because the EEC control register is located at address 40H in
Bank 1, the MP1 Memory Pointer must first be set to the value 40H and the Bank Pointer register,
BP, set to the value, 01H, before any operations on the EEC register are executed.
EEPROM Register List
• HT66F20-1/HT68F20-1
Name
Bit
7
6
5
4
3
2
1
0
EEA
—
—
—
D4
D3
D2
D1
D0
EED
D7
D6
D5
D4
D3
D2
D1
D0
EEC
—
—
—
—
WREN
WR
RDEN
RD
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
• HT66F30-1/HT68F30-1
Name
Bit
EEA Register
• HT66F20-1/HT68F20-1
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
—
—
—
x
x
x
x
x
“x” unknown
Bit 7~5 Unimplemented, read as “0”
Bit 4~0
D4~D0: Data EEPROM address
Data EEPROM address bit 4~bit 0
• HT66F30-1/HT68F30-1
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
Rev. 1.30
Bit 7~6 Unimplemented, read as “0”
Bit 5~0
D5~D0: Data EEPROM address
Data EEPROM address bit 5~bit 0
39
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
EEC Register
Bit
7
6
5
4
3
Name
—
—
—
—
R/W
—
—
—
—
POR
—
—
—
—
Bit 7~4
2
1
0
WREN
WR
RDEN
RD
R/W
R/W
R/W
R/W
0
0
0
0
Undefined, 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 1
RDEN: 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 0
RD : 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 to “1” at the same time in one instruction. The
WR and RD can not be set to “1” at the same time.
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 7~0
Rev. 1.30
D7~D0: Data EEPROM address
Data EEPROM address bit 7~bit 0
40
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
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
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. The EEPROM address of the data to be written must then be
placed in the EEA register and the data placed in the EED register. If the WR bit in the EEC register
is now set high, an internal write cycle will then be initiated. 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 Bank Pointer, BP, will be reset to zero, which means that Data
Memory Bank 0 will be selected. As the EEPROM control register is located in Bank 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 or read interrupt is generated when an EEPROM write or read 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 Multi-function 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.
Rev. 1.30
41
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
Programming Consideration
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 Bank Pointer could be normally cleared to zero as this would inhibit access to Bank 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.
Programming Examples
Reading Data from the EEPROM – Polling Method
MOV A, EEPROM_ADRES ; user defined address
MOV EEA, A
MOV A, 040H ; setup memory pointer MP1
MOV MP1, A ; MP1 points to EEC register
MOV A, 01H ; setup Bank Pointer
MOV BP, A
SET IAR1.1 ; set RDEN bit, enable read operations
SET IAR1.0 ; start Read Cycle - set RD bit
BACK:
SZ IAR1.0 ; check for read cycle end
JMP BACK
CLR IAR1 ; disable EEPROM read/write
CLR BP
MOV A, EED ; move read data to register
MOV READ_DATA, A
Writing Data from the EEPROM – Polling Method
MOV A, EEPROM_ADRES ; user defined address
MOV EEA, A
MOV A, EEPROM_DATA ; user defined data
MOV EED, A
MOV A, 040H ; setup memory pointer MP1
MOV MP1, A ; MP1 points to EEC register
MOV A, 01H ; setup Bank Pointer
MOV BP, A
SET IAR1.3 ; set WREN bit, enable write operations
SET IAR1.2 ; start Write Cycle - set WR bit
BACK:
SZ IAR1.2 ; check for write cycle end
JMP BACK
CLR IAR1 ; disable EEPROM read/write
CLR BP
Rev. 1.30
42
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
Oscillator
Various oscillator options offer the user a wide range of functions according to their various
application requirements. The flexible features of the oscillator functions ensure that the best
optimisation can be achieved in terms of speed and power saving. Oscillator selections and operation
are selected through a combination of configuration options and registers.
Oscillator Overview
In addition to being the source of the main system clock the oscillators also provide clock sources
for the Watchdog Timer and Time Base Interrupts. External oscillators requiring some external
components as well as fully integrated internal oscillators, requiring no external components,
are provided to form a wide range of both fast and slow system oscillators. All oscillator
options are selected through the configuration options. The higher frequency oscillators provide
higher performance but carry with it the disadvantage of higher power requirements, while the
opposite is of course true for the lower frequency oscillators. With the capability of dynamically
switching between fast and slow system clock, these devices have the flexibility to optimize the
performance/power ratio, a feature especially important in power sensitive portable applications.
Type
Name
Freq.
Pins
External Crystal
HXT
400kHz~20MHz
OSC1/OSC2
External RC
ERC
8MHz
OSC1
Internal High Speed RC
HIRC
4, 8, 12MHz
—
External Low Speed Crystal
LXT
32.768kHz
XT1/XT2
Internal Low Speed RC
LIRC
32kHz
—
Oscillator Types
System Clock Configurations
There are five methods of generating the system clock, three high speed oscillators and two low
speed oscillators. The high speed oscillators are the external crystal/ceramic oscillator, external
RC network oscillator and the internal 4MHz, 8MHz or 12MHz 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. 1.30
43
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
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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. 1.30
44
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
Crystal Oscillator C1 and C2 Values
Crystal Frequency
C1
C2
12MHz
0pF
0pF
8MHz
0pF
0pF
4MHz
0pF
0pF
1MHz
100pF
100pF
Note: 1. C1 and C2 values are for guidance only.
Crystal Recommended Capacitor Values
External RC Oscillator – ERC
Using the ERC oscillator only requires that a resistor, with a value between 56kΩ and 2.4MΩ, is
connected between OSC1 and VDD, and a capacitor is connected between OSC1 and ground,
providing a low cost oscillator configuration. It is only the external resistor that determines the
oscillation frequency; the external capacitor has no influence over the frequency and is connected
for stability purposes only. 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
resistance/frequency reference point, it can be noted that with an external 120kΩ resistor connected
and with a 5V voltage power supply and temperature of 25˚C degrees, the oscillator will have a
frequency of 8MHz within a tolerance of 2%. Here only the OSC1 pin is used, which is shared with
I/O pin PB1, leaving pin PB2 free for use as a normal I/O pin.
For oscillator stability and to minimise the effects of noise and crosstalk, it is important to locate the
capacitor and resistoras close to the MCU as possible.
External RC Oscillator — ERC
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 4MHz, 8MHz or 12MHz. Device
trimming during the manufacturing process and the inclusion of internal frequency compensation
circuits are used to ensure that the influence of the power supply voltage, temperature and process
variations on the oscillation frequency are minimised. As a result, at a power supply of either 3V or
5V and at a temperature of 25˚C degrees, the fixed oscillation frequency of 4MHz, 8MHz or 12MHz
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.
Rev. 1.30
45
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
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’s specification. The external
parallel feedback resistor, Rp, is required.
Some configuration options determine if the XT1/XT2 pins are used for the LXT oscillator or as I/O
pins.
• 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.
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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=5MΩ~10MΩ is recommended.
32.768kHz Crystal Recommended Capacitor Values
Rev. 1.30
46
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
LXT Oscillator Low Power Function
The LXT oscillator can function in one of two modes, the Quick Start Mode and the Low Power
Mode. The mode selection is executed using the LXTLP bit in the TBC register.
LXTLP Bit
LXT Mode
0
Quick Start
1
Low-power
After power on the LXTLP bit will be automatically cleared to zero ensuring that the LXT oscillator
is in the Quick Start operating mode. In the Quick Start Mode the LXT oscillator will power up
and stabilise quickly. However, after the LXT oscillator has fully powered up it can be placed
into the Low-power mode by setting the LXTLP bit high. The oscillator will continue to run but
with reduced current consumption, as the higher current consumption is only required during the
LXT oscillator start-up. In power sensitive applications, such as battery applications, where power
consumption must be kept to a minimum, it is therefore recommended that the application program
sets the LXTLP bit high about 2 seconds after power-on.
It should be noted that, no matter what condition the LXTLP bit is set to, the LXT oscillator will
always function normally, the only difference is that it will take more time to start up if in the
Low-power mode.
Internal 32kHz Oscillator – LIRC
The Internal 32kHz System Oscillator is one of the low frequency oscillator choices, which is
selected via configuration option. It is a fully integrated RC oscillator with a typical frequency of
32kHz at 5V, requiring no external components for its implementation. Device trimming during
the manufacturing process and the inclusion of internal frequency compensation circuits are used
to ensure that the influence of the power supply voltage, temperature and process variations on the
oscillation frequency are minimised. As a result, at a power supply of 5V and at a temperature of
25˚C degrees, the fixed oscillation frequency of 32kHz will have a tolerance within 10%.
Supplementary Clocks
The low speed oscillators, in addition to providing a system clock source are also used to provide
a clock source to two other devices functions. These are the Watchdog Timer and the Time Base
Interrupts.
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Operating Modes and System Clocks
Present day applications require that their microcontrollers have high performance but often still
demand that they consume as little power as possible, conflicting requirements that are especially
true in battery powered portable applications. The fast clocks required for high performance will
by their nature increase current consumption and of course vice versa, lower speed clocks reduce
current consumption. As Holtek has provided these devices with both high and low speed clock
sources and the means to switch between them dynamically, the user can optimise the operation of
their microcontroller to achieve the best performance/power ratio.
System Clocks
The devices have many different clock sources for both the CPU and peripheral function operation.
By providing the user with a wide range of clock options using configuration options and register
programming, a clock system can be configured to obtain maximum application performance.
The main system clock, can come from either a high frequency, fH, or low frequency, fL, source,
and is selected using the HLCLK bit and CKS2~CKS0 bits in the SMOD register. The high
speed system clock can be sourced from either a HXT, ERC or HIRC oscillator, selected via a
configuration option. The low speed system clock source can be sourced from internal clock fL. If fL
is selected then it can be sourced by either the LXT or LIRC oscillators, selected via a configuration
option. The other choice, which is a divided version of the high speed system oscillator has a range
of fH/2~fH/64.
There are two additional internal clocks for the peripheral circuits, the substitute clock, fSUB, and
the Time Base clock, fTBC. Each of these internal clocks is sourced by either the LXT or LIRC
oscillators, selected via configuration options. The fSUB clock is used to provide a substitute clock for
the microcontroller just after a wake-up has occurred to enable faster wake-up times.
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„ System Clock Configurations
Note: When the system clock source fSYS is switched to fL from fH, the high speed oscillation will
stop to conserve the power. Thus there is no fH~fH/64 for peripheral circuit to use.
Together with fSYS/4 it is also used as one of the clock sources for the Watchdog timer. The fTBC clock
is used as a source for the Time Base interrupt functions and for the TMs.
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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.
Description
Operation
Mode
CPU
fSYS
fSUB
fS
fTBC
NORMAL Mode
On
fH~fH/64
On
On
On
SLOW Mode
On
fL
On
On
On
IDLE0 Mode
Off
Off
On
On/Off
On
IDLE1 Mode
Off
On
On
On
On
SLEEP0 Mode
Off
Off
Off
Off
Off
SLEEP1 Mode
Off
Off
On
On
Off
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, ERC or HIRC oscillators. The high speed
oscillator will however first be divided by a ratio ranging from 1 to 64, the actual ratio being selected
by the CKS2~CKS0 and HLCLK bits in the SMOD register. Although a high speed oscillator is
used, running the microcontroller at a divided clock ratio reduces the operating current.
SLOW Mode
This is also a mode where the microcontroller operates normally although now with a slower speed
clock source. The clock source used will be from one of the low speed oscillators, either the LXT
or the LIRC. Running the microcontroller in this mode allows it to run with much lower operating
currents. In the SLOW Mode, the fH is off.
SLEEP0 Mode
The SLEEP0 Mode is entered when an HALT instruction is executed and when the IDLEN bit in the
SMOD register is low. In the SLEEP0 mode the CPU will be stopped, and the fSUB and fS clocks will
be stopped too, and the Watchdog Timer function is disabled. In this mode, the LVDEN is must set
to "0". If the LVDEN is set to "1", it won’t enter the SLEEP0 Mode.
SLEEP1 Mode
The SLEEP1 Mode is entered when an HALT instruction is executed and when the IDLEN bit in
the SMOD register is low. In the SLEEP1 mode the CPU will be stopped. However, the fSUB 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.
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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 WDTC register is low. In the IDLE0 Mode the
system oscillator will be inhibited from driving the CPU but some peripheral functions will remain
operational such as the Watchdog Timer, TMs and SIM. In the IDLE0 Mode, the system oscillator
will be stopped. In the IDLE0 Mode the Watchdog Timer clock, 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 WDTC register is high. In the IDLE1 Mode
the system oscillator will be inhibited from driving the CPU but may continue to provide a clock
source to keep some peripheral functions operational such as the Watchdog Timer, TMs and SIM. In
the IDLE1 Mode, the system oscillator will continue to run, and this system oscillator may be high
speed or low speed system oscillator. In the IDLE1 Mode the Watchdog Timer clock, 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
A single register, SMOD, is used for overall control of the internal clocks within these devices.
SMOD Register
Bit
7
6
5
4
3
2
1
0
Name
CKS2
CKS1
CKS0
FSTEN
LTO
HTO
IDLEN
HLCLK
R/W
R/W
R/W
R/W
R/W
R
R
R/W
R/W
POR
0
0
0
0
0
0
1
1
Bit 7~5CKS2~CKS0: The system clock selection when HLCLK is “0”
000: fL (fLXT or fLIRC)
001: fL (fLXT or fLIRC)
010: fH/64
011: fH/32
100: fH/16
101: fH/8
110: fH/4
111: fH/2
These three bits are used to select which clock is used as the system clock source. In
addition to the system clock source, which can be either the LXT or LIRC, a divided
version of the high speed system oscillator can also be chosen as the system clock
source.
Bit 4FSTEN: Fast Wake-up Control (only for HXT)
0: Disable
1: Enable
This is the Fast Wake-up Control bit which determines if the fSUB clock source is
initially used after these devices wake 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.
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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 “0” by hardware when these
devices are powered on and then changes to a high level after the high speed system
oscillator is stable. Therefore this flag will always be read as “1” by the application
program after devices power-on. The flag will be low when in the SLEEP or IDLE0
Mode but after a wake-up has occurred, the flag will change to a high level after 1024
clock cycles if the HXT oscillator is used and after 15~16 clock cycles if the ERC or
HIRC oscillator is used.
Bit 1IDLEN: IDLE Mode control
0: Disable
1: Enable
This is the IDLE Mode Control bit and determines what happens when the HALT
instruction is executed. If this bit is high, when a HALT instruction is executed these
devices will enter the IDLE Mode. In the IDLE1 Mode the CPU will stop running
but the system clock will continue to keep the peripheral functions operational, if
FSYSON bit is high. If FSYSON bit is low, the CPU and the system clock will all
stop in IDLE0 mode. If the bit is low these devices will enter the SLEEP Mode when a
HALT instruction is executed.
Bit 0HLCLK: System clock selection
0: fH/2~fH/64 or fL
1: fH
This bit is used to select if the fH clock or the fH/2~fH/64 or fL clock is used as the
system clock. When the bit is high the f H clock will be selected and if low the
fH/2~fH/64 or fL clock will be selected. When system clock switches from the fH clock
to the fL clock and the fH clock will be automatically switched off to conserve power.
Fast Wake-up
To minimise power consumption these devices can enter the SLEEP or IDLE0 Mode, where the
system clock source to these devices will be stopped. However when these devices are woken
up again, it can take a considerable time for the original system oscillator to restart, stabilise and
allow normal operation to resume. To ensure the device is up and running as fast as possible a Fast
Wake-up function is provided, which allows fSUB, namely either the LXT or LIRC oscillator, to act
as a temporary clock to first drive the system until the original system oscillator has stabilised. As
the clock source for the Fast Wake-up function is fSUB, the Fast Wake-up function is only available in
the SLEEP1 and IDLE0 modes. When these devices are woken up from the SLEEP0 mode, the Fast
Wake-up function has no effect because the fSUB clock is stopped. The Fast Wake-up enable/disable
function is controlled using the FSTEN bit in the SMOD register.
If the HXT oscillator is selected as the NORMAL Mode system clock, and if the Fast Wake-up
function is enabled, then it will take one to two tSUB clock cycles of the LIRC or LXT oscillator for
the system to wake-up. The system will then initially run under the fSUB clock source until 1024
HXT clock cycles have elapsed, at which point the HTO flag will switch high and the system will
switch over to operating from the HXT oscillator.
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If the ERC or HIRC oscillator or LIRC oscillator is used as the system oscillator then it will take
15~16 clock cycles of the ERC or HIRC or 1~2 cycles of the LIRC to wake up the system from the
SLEEP or IDLE0 Mode. The Fast Wake-up bit, FSTEN will have no effect in these cases.
System FSTEN
Oscillator
Bit
Wake-up Time
(SLEEP0 Mode)
Wake-up Time
(SLEEP1 Mode)
Wake-up Time
(IDLE0 Mode)
Wake-up Time
(IDLE1 Mode)
1024 HXT cycles
1024 HXT cycles
1
1024 HXT cycles
1~2 fSUB cycles (System runs with fSUB first
for 1024 HXT cycles and then switches
1~2 HXT cycles
over to run with the HXT clock)
ERC
x
15~16 ERC cycles 15~16 ERC cycles
1~2 ERC cycles
HIRC
x
15~16 HIRC cycles 15~16 HIRC cycles
1~2 HIRC cycles
LIRC
x
1~2 LIRC cycles
1~2 LIRC cycles
1~2 LIRC cycles
LXT
x
1024 LTX cycles
1024 LXT cycles
1~2 LXT cycles
0
HXT
1~2 HXT cycles
Wake-Up Times
Note that if the Watchdog Timer is disabled, which means that the LXT and LIRC are all both off,
then there will be no Fast Wake-up function available when these devices wake-up from the SLEEP0
Mode.
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Operating Mode Switching
These devices can switch between operating modes dynamically allowing the user to select the best
performance/power ratio for the present task in hand. In this way microcontroller operations that
do not require high performance can be executed using slower clocks thus requiring less operating
current and prolonging battery life in portable applications.
In simple terms, Mode Switching between the NORMAL Mode and SLOW Mode is executed
using the HLCLK bit and CKS2~CKS0 bits in the SMOD register while Mode Switching from the
NORMAL/SLOW Modes to the SLEEP/IDLE Modes is executed via the HALT instruction. When
a HALT instruction is executed, whether these devices enter the IDLE Mode or the SLEEP Mode
is determined by the condition of the IDLEN bit in the SMOD register and FSYSON in the WDTC
register.
When the HLCLK bit switches to a low level, which implies that clock source is switched from the
high speed clock source, fH, to the clock source, fH/2~fH/64 or fL. If the clock is from the fL, the high
speed clock source will stop running to conserve power. When this happens it must be noted that the
fH/16 and fH/64 internal clock sources will also stop running, which may affect the operation of other
internal functions such as the TMs and the SIM. The accompanying flowchart shows what happens
when these devices move between the various operating modes.
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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In SLOW Mode the system uses either the LXT or LIRC low speed system oscillator. To switch
back to the NORMAL Mode, where the high speed system oscillator is used, the HLCLK bit should
be set to “1” or HLCLK bit is “0”, but CKS2~CKS0 is set to “010”, “011”, “100”, “101”, “110”
or “111”. As a certain amount of time will be required for the high frequency clock to stabilise,
the status of the HTO bit is checked. The amount of time required for high speed system oscillator
stabilization depends upon which high speed system oscillator type is used.
Entering the SLEEP0 Mode
There is only one way for these devices to enter the SLEEP0 Mode and that is to execute the “HALT”
instruction in the application program with the IDLEN bit in SMOD register equal to “0” and the
WDT and LVD both off. When this instruction is executed under the conditions described above, the
following will occur:
• The system clock, WDT clock and Time Base clock will be stopped and the application program
will stop at the “HALT” instruction.
• The Data Memory contents and registers will maintain their present condition.
• The WDT will be cleared and stopped 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.
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Entering the SLEEP1 Mode
There is only one way for these devices to enter the SLEEP1 Mode and that is to execute the “HALT”
instruction in the application program with the IDLEN bit in SMOD register equal to “0” and the
WDT or LVD on. When this instruction is executed under the conditions described above, the
following will occur:
• The system clock and Time Base clock will be stopped and the application program will stop at
the “HALT” instruction, but the WDT or LVD will remain with the clock source coming from the
fSUB clock.
• The Data Memory contents and registers will maintain their present condition.
• The WDT will be cleared and resume counting if the WDT 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 these devices to enter the IDLE0 Mode and that is to execute the “HALT”
instruction in the application program with the IDLEN bit in SMOD register equal to “1” and the
FSYSON bit in WDTC register equal to “0”. When this instruction is executed under the conditions
described above, the following will occur:
• The system clock will be stopped and the application program will stop at the “HALT”
instruction, but the Time Base clock and fSUB clock will be on.
• The Data Memory contents and registers will maintain their present condition.
• The WDT will be cleared and resume counting if the WDT 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.
Entering the IDLE1 Mode
There is only one way for these devices to enter the IDLE1 Mode and that is to execute the “HALT”
instruction in the application program with the IDLEN bit in SMOD register equal to “1” and the
FSYSON bit in WDTC register equal to “1”. When this instruction is executed under the conditions
described above, the following will occur:
• The system clock and Time Base clock and fSUB clock will be on and the application program will
stop at the “HALT” instruction.
• The Data Memory contents and registers will maintain their present condition.
• The WDT will be cleared and resume counting if the WDT is enabled 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.
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Standby Current Considerations
As the main reason for entering the SLEEP or IDLE Mode is to keep the current consumption of
these devices to as low a value as possible, perhaps only in the order of several micro-amps except
in the IDLE1 Mode, there are other considerations which must also be taken into account by the
circuit designer if the power consumption is to be minimised. Special attention must be made to
the I/O pins on these devices. All high-impedance input pins must be connected to either a fixed
high or low level as any floating input pins could create internal oscillations and result in increased
current consumption. This also applies to devices which have different package types, as there may
be unbonded pins. These must either be setup as outputs or if setup as inputs must have pull-high
resistors connected.
Care must also be taken with the loads, which are connected to I/O pins, which are setup as outputs.
These should be placed in a condition in which minimum current is drawn or connected only to
external circuits that do not draw current, such as other CMOS inputs. Also note that additional
standby current will also be required if the configuration options have enabled the LXT or LIRC
oscillator.
In the IDLE1 Mode the system oscillator is on, if the system oscillator is from the high speed
system oscillator, the additional standby current will also be perhaps in the order of several hundred
micro-amps.
Wake-up
After the system enters the SLEEP or IDLE Mode, it can be woken up from one of various sources
listed as follows:
• An external reset
• An external falling edge on Port A
• A system interrupt
• A WDT overflow
If the system is woken up by an external reset, these devices will experience a full system reset,
however, if these devices are woken up by a WDT overflow, a Watchdog Timer reset will be
initiated. Although both of these wake-up methods will initiate a reset operation, the actual source
of the wake-up can be determined by examining the TO and PDF flags. The PDF flag is cleared by a
system power-up or executing the clear Watchdog Timer instructions and is set when executing the
“HALT” instruction. The TO flag is set if a WDT time-out occurs, and causes a wake-up that only
resets the Program Counter and Stack Pointer, the other flags remain in their original status.
Each pin on 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 these devices will
not be immediately serviced, but will rather be serviced later when the related interrupt is finally
enabled or when a stack level becomes free. The other situation is where the related interrupt is
enabled and the stack is not full, in which case the regular interrupt response takes place. If an
interrupt request flag is set high before entering the SLEEP or IDLE Mode, the wake-up function of
the related interrupt will be disabled.
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Programming Considerations
The HXT and LXT oscillators both use the same SST counter. For example, if the system is woken
up from the SLEEP0 Mode and both the HXT and LXT oscillators need to start-up from an off state.
The LXT oscillator uses the SST counter after HXT oscillator has finished its SST period.
• If these devices are woken up from the SLEEP0 Mode to the NORMAL Mode, the high speed
system oscillator needs an SST period. These devices will execute first instruction after HTO
is “1”. At this time, the LXT oscillator may not be stability if fSUB is from LXT oscillator. The
same situation occurs in the power-on state. The LXT oscillator is not ready yet when the first
instruction is executed.
• If these devices are woken up from the SLEEP1 Mode to NORMAL Mode, and the system clock
source is from HXT oscillator and FSTEN is “1”, the system clock can be switched to the LXT
or LIRC oscillator after wake up.
• There are peripheral functions, such as WDT, TMs and SIM, for which the fSYS is used. If the
system clock source is switched from fH to fL, the clock source to the peripheral functions
mentioned above will change accordingly.
• The on/off condition of fSUB and fS depends upon whether the WDT is enabled or disabled as the
WDT clock source is selected from fSUB.
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 215 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. The Watchdog Timer clock source can
originate from its own internal LIRC oscillator, the LXT oscillator or fSYS/4. It is divided by a value
of 28 to 215, using the WS2~WS0 bits in the WDTC register to obtain the required Watchdog Timer
time-out period.
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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
Rev. 1.30
Bit
7
6
5
4
Name
FSYSON
WS2
WS1
WS0
3
2
1
0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
1
1
1
1
0
1
0
WDTEN3 WDTEN2 WDTEN1 WDTEN0
Bit 7
FSYSON: fSYS Control in IDLE Mode
0: Disable
1: Enable
Bit 6~4
WS2, WS1, WS0: WDT time-out period selection
000: 256/fS
001: 512/fS
010: 1024/fS
011: 2048/fS
100: 4096/fS
101: 8192/fS
110: 16384/fS
111: 32768/fS
These three bits determine the division ratio of the Watchdog Timer source clock,
which in turn determines the timeout period.
Bit 3~0
WDTEN3, WDTEN2, WDTEN1, WDTEN0: WDT Software Control
1010: Disable
Other: Enable
59
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
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 unkown 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 enable/disable, clock source selection and clear instruction type
are selected using configuration options. In addition to a configuration option to enable/disable the
Watchdog Timer, there are also four bits, WDTEN3~WDTEN0, in the WDTC register to offer an
additional enable/disable control of the Watchdog Timer. To disable the Watchdog Timer, as well
as the configuration option being set to disable, the WDTEN3~WDTEN0 bits must also be set to
a specific value of "1010". Any other values for these bits will keep the Watchdog Timer enabled,
irrespective of the configuration enable/disable setting. After power on these bits will have the value
of 1010. If the Watchdog Timer is used it is recommended that they are set to a value of 0101 for
maximum noise immunity. Note that if the Watchdog Timer has been disabled, then any instruction
relating to its operation will result in no operation.
WDT Configuration Option
WDTEN3~WDTEN0 Bits
WDT
WDT Enable
xxxx
Enable
WDT Disable
Except 1010
Enable
WDT Disable
1010
Disable
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 an external hardware reset, which means a low level on the RES pin, the second is using
the Watchdog Timer software clear instructions and the third is via a HALT instruction.
There are two methods of using software instructions to clear the Watchdog Timer, one of which
must be chosen by configuration option. The first option is to use the single "CLR WDT" instruction
while the second is to use the two commands "CLR WDT1" and "CLR WDT2". For the first option,
a simple execution of "CLR WDT" will clear the WDT while for the second option, both "CLR
WDT1" and "CLR WDT2" must both be executed alternately to successfully clear the Watchdog
Timer. Note that for this second option, if "CLR WDT1" is used to clear the Watchdog Timer,
successive executions of this instruction will have no effect, only the execution of a "CLR WDT2" instruction will clear the Watchdog Timer. Similarly after the "CLR WDT2" instruction has been
executed, only a successive "CLR WDT1" instruction can clear the Watchdog Timer.
The maximum time out period is when the 215 division ratio is selected. As an example, with a
32.768kHz LXT oscillator as its source clock, this will give a maximum watchdog period of around
1 second for the 215 division ratio, and a minimum timeout of 7.8ms for the 28 division ration. If the
fSYS/4 clock is used as the Watchdog Timer clock source, it should be noted that when the system
enters the SLEEP or IDLE0 Mode, then the instruction clock is stopped and the Watchdog Timer
may lose its protecting purposes. For systems that operate in noisy environments, using the fSUB
clock source is strongly recommended.
Rev. 1.30
60
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
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Watchdog Timer
Reset and Initialisation
A reset function is a fundamental part of any microcontroller ensuring that the device can be set
to some predetermined condition irrespective of outside parameters. 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.
In addition to the power-on reset, situations may arise where it is necessary to forcefully apply a
reset condition when the is running. One example of this is where after power has been applied
and the is already running, the RES line is forcefully pulled low. In such a case, known as a normal
operation reset, some of the registers remain unchanged allowing the to proceed with normal
operation after the reset line is allowed to return high.
Another type of reset is when the Watchdog Timer overflows and resets the microcontroller. All
types of reset operations result in different register conditions being setup. Another reset exists in
the form of a Low Voltage Reset, LVR, where a full reset, similar to the RES reset is implemented in
situations where the power supply voltage falls below a certain threshold.
Reset Functions
There are five ways in which a microcontroller reset can occur, through events occurring both
internally and externally:
Power-on Reset
The most fundamental and unavoidable reset is the one that occurs after power is first applied to
the microcontroller. As well as ensuring that the Program Memory begins execution from the first
memory address, a power-on reset also ensures that certain other registers are preset to known
conditions. All the I/O port and port control registers will power up in a high condition ensuring that
all pins will be first set to inputs.
Note: tRSTD is power-on delay, typical time=100ms
Power-on Reset Timing Chart
Rev. 1.30
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May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
RES Pin
As the reset pin is shared with PB.0, the reset function must be selected using a configuration
option. Although the microcontroller has an internal RC reset function, if the VDD power supply
rise time is not fast enough or does not stabilise quickly at power-on, the internal reset function
may be incapable of providing proper reset operation. For this reason it is recommended that an
external RC network is connected to the RES pin, whose additional time delay will ensure that the
RES pin remains low for an extended period to allow the power supply to stabilise. During this time
delay, normal operation of the microcontroller will be inhibited. After the RES line reaches a certain
voltage value, the reset delay time tRSTD is invoked to provide an extra delay time after which the
microcontroller will begin normal operation. The abbreviation SST in the figures stands for System
Start-up Timer.
For most applications a resistor connected between VDD and the RES pin and a capacitor connected
between VSS and the RES pin will provide a suitable external reset circuit. Any wiring connected to
the RES pin should be kept as short as possible to minimise any stray noise interference.
For applications that operate within an environment where more noise is present the Enhanced Reset
Circuit shown is recommended.
Note: * It is recommended that this component is added for added ESD protection.
** It is recommended that this component is added in environments where power line
noise is significant.
Extern RES Circuit
More information regarding external reset circuits is located in Application Note HA0075E on the
Holtek website.
Pulling the RES Pin low using external hardware will also execute a device reset. In this case, as in
the case of other resets, the Program Counter will reset to zero and program execution initiated from
this point.
Note: tRSTD is power-on delay, typical time=100ms
RES Reset Timing Chart
Rev. 1.30
62
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
Low Voltage Reset – LVR
These microcontrollers contain a low voltage reset circuit in order to monitor the supply voltage
of these devices, which are selected via a configuration option. 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. The LVR includes the following specifications: For a valid
LVR signal, a low voltage, i.e., a voltage in the range between 0.9V~VLVR must exist for greater than
the value tLVR specified in the A.C. characteristics. If the low voltage state does not exceed tLVR, the
LVR will ignore it and will not perform a reset function. One of a range of specified voltage values
for VLVR can be selected using configuration options.
Note: tRSTD is power-on delay, typical time=100ms
Low Voltage Reset Timing Chart
Watchdog Time-out Reset during Normal Operation
The Watchdog time-out Reset during normal operation is the same as a hardware RES pin reset
except that the Watchdog time-out flag TO will be set to “1”.
Note: tRSTD is power-on delay, typical time=100ms
WDT Time-out Reset during Normal Operation Timing Chart
Watchdog Time-out Reset during SLEEP or IDLE Mode
The Watchdog time-out Reset during SLEEP or IDLE Mode is a little different from other kinds
of reset. Most of the conditions remain unchanged except that the Program Counter and the Stack
Pointer will be cleared to “0” and the TO flag will be set to “1”. Refer to the A.C. Characteristics for
tSST details.
Note: The tSST is 15~16 clock cycles if the system clock source is provided by ERC or 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 Timing Chart
Rev. 1.30
63
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
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
RES or 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
“u” stands for unchanged
The following table indicates the way in which the various components of the microcontroller are
affected after a power-on reset occurs.
Item
Condition After RESET
Program Counter
Reset to zero
Interrupts
All interrupts will be disabled
WDT
Clear after reset, WDT begins counting
Timer/Event Counter
Timer Counter will be turned off
Input/Output Ports
I/O ports will be setup as inputs, and AN0~AN7 is as A/D input pin.
Stack Pointer
Stack Pointer will point to the top of the stack
The different kinds of resets all affect the internal registers of the microcontroller in different ways.
To ensure reliable continuation of normal program execution after a reset occurs, it is important to
know what condition the microcontroller is in after a particular reset occurs. The following table
describes how each type of reset affects each of the microcontroller internal registers. Note that
where more than one package type exists the table will reflect the situation for the larger package
type.
HT66F20-1
Reset
(Power-on)
RES or LVR Reset
WDT Time-out
(Normal Operation)
WDT Time-out
(IDLE)
MP0
xxxx xxxx
uuuu uuuu
uuuu uuuu
uuuu uuuu
MP1
xxxx xxxx
uuuu uuuu
uuuu uuuu
uuuu uuuu
BP
---- ---0
---- ---0
---- ---0
---- ---u
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
---- --xx
---- --uu
---- --uu
---- --uu
STATUS
--00 xxxx
--uu uuuu
- - 1u uuuu
- - 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
LVDC
--00 -000
--00 -000
--00 -000
--uu -uuu
INTEG
---- 0000
---- 0000
---- 0000
---- uuuu
WDTC
0 111 1 0 1 0
0 111 1 0 1 0
0 111 1 0 1 0
uuuu uuuu
TBC
0 0 11 0 111
0 0 11 0 111
0 0 11 0 111
uuuu uuuu
INTC0
-000 0000
-000 0000
-000 0000
-uuu uuuu
INTC1
0000 0000
0000 0000
0000 0000
uuuu uuuu
INTC2
0000 0000
0000 0000
0000 0000
uuuu uuuu
MFI0
--00 --00
--00 --00
--00 --00
--uu --uu
Register
Rev. 1.30
64
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
Reset
(Power-on)
RES or LVR Reset
WDT Time-out
(Normal Operation)
WDT Time-out
(IDLE)
MFI1
--00 --00
--00 --00
--00 --00
--uu --uu
MFI2
0000 0000
0000 0000
0000 0000
uuuu uuuu
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
--00 0000
--00 0000
--00 0000
--uu uuuu
PB
- - 11 1111
- - 11 1111
- - 11 1111
--uu uuuu
PBC
- - 11 1111
- - 11 1111
- - 11 1111
--uu uuuu
PCPU
---- 0000
---- 0000
---- 0000
---- uuuu
PC
- - - - 1111
- - - - 1111
- - - - 1111
---- uuuu
PCC
- - - - 1111
- - - - 1111
- - - - 1111
---- uuuu
ADRL(ADREF=0)
xxxx ----
xxxx ----
xxxx ----
uuuu ----
ADRL(ADREF=1)
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
ADRH(ADREF=0)
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
ADRH(ADREF=1)
---- xxxx
---- xxxx
---- xxxx
---- uuuu
ADCR0
0 11 0 - 0 0 0
0 11 0 - 0 0 0
0 11 0 - 0 0 0
uuuu -uuu
ADCR1
00-0 -000
00-0 -000
00-0 -000
uu-u -uuu
ACERL
1111 1111
1111 1111
1111 1111
uuuu uuuu
CP0C
1000 0--1
1000 0--1
1000 0--1
uuuu u--u
CP1C
1000 0--1
1000 0--1
1000 0--1
uuuu u--u
SIMC0
111 0 0 0 0 -
111 0 0 0 0 -
111 0 0 0 0 -
uuuu uuu-
SIMC1
1000 0001
1000 0001
1000 0001
uuuu uuuu
SIMD
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
SIMA/SIMC2
0000 0000
0000 0000
0000 0000
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
EEA
- - - x xxxx
- - - x xxxx
- - - x xxxx
- - - 0 0000
EED
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
Register
EEC
---- 0000
---- 0000
---- 0000
---- uuuu
TMPC0
--01 ---1
--01 ---1
--01 ---1
--uu ---u
TM1C0
0000 0000
0000 0000
0000 0000
uuuu uuuu
TM1C1
0000 0000
0000 0000
0000 0000
uuuu uuuu
TM1DL
0000 0000
0000 0000
0000 0000
uuuu uuuu
TM1DH
---- --00
---- --00
---- --00
---- --uu
TM1AL
0000 0000
0000 0000
0000 0000
uuuu uuuu
TM1AH
---- --00
---- --00
---- --00
---- --uu
SCOMC
0000 0000
0000 0000
0000 0000
uuuu uuuu
Note: "u" stands for unchanged
“x” stands for unknown
“-” stands for unimplemented
Rev. 1.30
65
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
HT66F30-1 Register
Reset
(Power-on)
RES or
LVR Reset
WDT Time-out
(Normal Operation)
WDT Time-out
(IDLE)
MP0
-xxx xxxx
-xxx xxxx
-xxx xxxx
-uuu uuuu
MP1
-xxx xxxx
-xxx xxxx
-xxx xxxx
-uuu uuuu
Register
BP
---- ---0
---- ---0
---- ---0
---- ---u
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
---- -xxx
---- -uuu
---- -uuu
---- -uuu
STATUS
--00 xxxx
--uu uuuu
--1u uuuu
- - 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
LVDC
--00 -000
--00 -000
--00 -000
--uu -uuu
INTEG
---- 0000
---- 0000
---- 0000
---- uuuu
WDTC
0 111 1 0 1 0
0 111 1 0 1 0
0 111 1 0 1 0
uuuu uuuu
TBC
0 0 11 0 111
0 0 11 0 111
0 0 11 0 111
uuuu uuuu
INTC0
-000 0000
-000 0000
-000 0000
-uuu uuuu
INTC1
0000 0000
0000 0000
0000 0000
uuuu uuuu
INTC2
0000 0000
0000 0000
0000 0000
uuuu uuuu
MFI0
--00 --00
--00 --00
--00 --00
--uu --uu
MFI1
-000 -000
-000 -000
-000 -000
-uuu -uuu
MFI2
0000 0000
0000 0000
0000 0000
uuuu uuuu
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
--00 0000
--00 0000
--00 0000
--uu uuuu
PB
- - 11 1111
- - 11 1111
- - 11 1111
--uu uuuu
PBC
- - 11 1111
- - 11 1111
- - 11 1111
--uu uuuu
PCPU
0000 0000
0000 0000
0000 0000
uuuu uuuu
PC
1111 1111
1111 1111
1111 1111
uuuu uuuu
PCC
1111 1111
1111 1111
1111 1111
uuuu uuuu
ADRL(ADREF=0)
xxxx ----
xxxx ----
xxxx ----
uuuu ----
ADRL(ADREF=1)
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
ADRH(ADREF=0)
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
ADRH(ADREF=1)
---- xxxx
---- xxxx
---- xxxx
---- uuuu
ADCR0
0 11 0 - 0 0 0
0 11 0 - 0 0 0
0 11 0 - 0 0 0
uuuu -uuu
ADCR1
00-0 -000
00-0 -000
00-0 -000
uu-u -uuu
ACERL
1111 1111
1111 1111
1111 1111
uuuu uuuu
CP0C
1000 0--1
1000 0--1
1000 0--1
uuuu u--u
CP1C
1000 0--1
1000 0--1
1000 0--1
uuuu u--u
SIMC0
111 0 0 0 0 -
111 0 0 0 0 -
111 0 0 0 0 -
uuuu uuu-
SIMC1
1000 0001
1000 0001
1000 0001
uuuu uuuu
SIMD
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
SIMA/SIMC2
0000 0000
0000 0000
0000 0000
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
Rev. 1.30
66
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
Reset
(Power-on)
RES or
LVR Reset
WDT Time-out
(Normal Operation)
WDT Time-out
(IDLE)
TM0DH
---- --00
---- --00
---- --00
---- --uu
TM0AL
0000 0000
0000 0000
0000 0000
uuuu uuuu
TM0AH
---- --00
---- --00
---- --00
---- --uu
EEA
--xx xxxx
--xx xxxx
--xx xxxx
--uu uuuu
Register
EED
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
EEC
---- 0000
---- 0000
---- 0000
---- uuuu
TMPC0
1-01 --01
1-01 --01
1-01 --01
u-uu --uu
PRM0
---- -000
---- -000
---- -000
---- -uuu
TM1C0
0000 0000
0000 0000
0000 0000
uuuu uuuu
TM1C1
0000 0000
0000 0000
0000 0000
uuuu uuuu
TM1C2
0000 0000
0000 0000
0000 0000
uuuu uuuu
TM1DL
0000 0000
0000 0000
0000 0000
uuuu uuuu
TM1DH
---- --00
---- --00
---- --00
---- --uu
TM1AL
0000 0000
0000 0000
0000 0000
uuuu uuuu
TM1AH
---- --00
---- --00
---- --00
---- --uu
TM1BL
0000 0000
0000 0000
0000 0000
uuuu uuuu
TM1BH
---- --00
---- --00
---- --00
---- --uu
SCOMC
0000 0000
0000 0000
0000 0000
uuuu uuuu
Note: “ - ” stands for not implement
“ u ” stands for unchanged
“ x ” stands for unknown
HT68F20-1
Reset
(Power-on)
RES or
LVR Reset
WDT Time-out
(Normal Operation)
WDT Time-out
(IDLE)
MP0
xxxx xxxx
uuuu uuuu
uuuu uuuu
uuuu uuuu
MP1
xxxx xxxx
uuuu uuuu
uuuu uuuu
uuuu uuuu
BP
---- ---0
---- ---0
---- ---0
---- ---u
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
---- --xx
---- --uu
---- --uu
---- --uu
STATUS
--00 xxxx
--uu uuuu
--1u uuuu
- - 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
LVDC
--00 -000
--00 -000
--00 -000
--uu -uuu
INTEG
---- 0000
---- 0000
---- 0000
---- uuuu
WDTC
0 111 1 0 1 0
0 111 1 0 1 0
0 111 1 0 1 0
uuuu uuuu
TBC
0 0 11 0 111
0 0 11 0 111
0 0 11 0 111
uuuu uuuu
INTC0
- 000 0000
- 000 0000
- 000 0000
- uuu uuuu
INTC1
0000 0000
0000 0000
0000 0000
uuuu uuuu
INTC2
0000 0000
0000 0000
0000 0000
uuuu uuuu
MFI0
--00 --00
--00 --00
--00 --00
--uu --uu
MFI1
--00 --00
--00 --00
--00 --00
--uu --uu
MFI2
0000 0000
0000 0000
0000 0000
uuuu uuuu
PAWU
0000 0000
0000 0000
0000 0000
uuuu uuuu
PAPU
0000 0000
0000 0000
0000 0000
uuuu uuuu
Register
Rev. 1.30
67
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
Register
Reset
(Power-on)
RES or
LVR Reset
WDT Time-out
(Normal Operation)
WDT Time-out
(IDLE)
PA
1111 1111
1111 1111
1111 1111
uuuu uuuu
PAC
1111 1111
1111 1111
1111 1111
uuuu uuuu
PBPU
--00 0000
--00 0000
--00 0000
--uu uuuu
PB
- - 11 1111
- - 11 1111
- - 11 1111
--uu uuuu
PBC
- - 11 1111
- - 11 1111
- - 11 1111
--uu uuuu
PCPU
---- 0000
---- 0000
---- 0000
---- uuuu
PC
- - - - 1111
- - - - 1111
- - - - 1111
---- uuuu
PCC
- - - - 1111
- - - - 1111
- - - - 1111
---- uuuu
CP0C
1000 0--1
1000 0--1
1000 0--1
uuuu u--u
CP1C
1000 0--1
1000 0--1
1000 0--1
uuuu u--u
SIMC0
111 0 0 0 0 -
111 0 0 0 0 -
111 0 0 0 0 -
uuuu uuu-
SIMC1
1000 0001
1000 0001
1000 0001
uuuu uuuu
SIMD
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
SIMA/SIMC2
0000 0000
0000 0000
0000 0000
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
EEA
---x xxxx
---x xxxx
---x xxxx
- - - 0 0000
EED
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
EEC
---- 0000
---- 0000
---- 0000
---- uuuu
TMPC0
--01 ---1
--01 ---1
--01 ---1
--uu ---u
TM1C0
0000 0000
0000 0000
0000 0000
uuuu uuuu
TM1C1
0000 0000
0000 0000
0000 0000
uuuu uuuu
TM1DL
0000 0000
0000 0000
0000 0000
uuuu uuuu
TM1DH
---- --00
---- --00
---- --00
---- --uu
TM1AL
0000 0000
0000 0000
0000 0000
uuuu uuuu
TM1AH
---- --00
---- --00
---- --00
---- --uu
SCOMC
0000 0000
0000 0000
0000 0000
uuuu uuuu
Note: "u" stands for unchanged
"x" stands for unknown
"–" stands for unimplemented
Rev. 1.30
68
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
HT68F30-1 Register
Reset
(Power-on)
RES or LVR
Reset
WDT Time-out
(Normal Operation)
WDT Time-out
(IDLE)
MP0
-xxx xxxx
-xxx xxxx
-xxx xxxx
-uuu uuuu
MP1
-xxx xxxx
-xxx xxxx
-xxx xxxx
-uuu uuuu
BP
---- ---0
---- ---0
---- ---0
---- ---u
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
---- -xxx
---- -uuu
---- -uuu
---- -uuu
STATUS
--00 xxxx
--uu uuuu
--1u uuuu
- - 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
LVDC
--00 -000
--00 -000
--00 -000
--uu -uuu
INTEG
---- 0000
---- 0000
---- 0000
---- uuuu
WDTC
0 111 1 0 1 0
0 111 1 0 1 0
0 111 1 0 1 0
uuuu uuuu
TBC
0 0 11 0 111
0 0 11 0 111
0 0 11 0 111
uuuu uuuu
INTC0
-000 0000
-000 0000
-000 0000
-uuu uuuu
INTC1
0000 0000
0000 0000
0000 0000
uuuu uuuu
INTC2
0000 0000
0000 0000
0000 0000
uuuu uuuu
MFI0
--00 --00
--00 --00
--00 --00
--uu --uu
MFI1
-000 -000
-000 -000
-000 -000
-uuu -uuu
MFI2
0000 0000
0000 0000
0000 0000
uuuu uuuu
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
--00 0000
--00 0000
--00 0000
--uu uuuu
PB
- - 11 1111
- - 11 1111
- - 11 1111
--uu uuuu
PBC
- - 11 1111
- - 11 1111
- - 11 1111
--uu uuuu
PCPU
0000 0000
0000 0000
0000 0000
uuuu uuuu
PC
1111 1111
1111 1111
1111 1111
uuuu uuuu
PCC
1111 1111
1111 1111
1111 1111
uuuu uuuu
CP0C
1000 0--1
1000 0--1
1000 0--1
uuuu u--u
CP1C
1000 0--1
1000 0--1
1000 0--1
uuuu u--u
SIMC0
111 0 0 0 0 -
111 0 0 0 0 -
111 0 0 0 0 -
uuuu uuu-
SIMC1
1000 0001
1000 0001
1000 0001
uuuu uuuu
SIMD
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
SIMA/SIMC2
0000 0000
0000 0000
0000 0000
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
EEA
--xx xxxx
--xx xxxx
--xx xxxx
--uu uuuu
EED
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
EEC
---- 0000
---- 0000
---- 0000
---- uuuu
TMPC0
1-01 --01
1-01 --01
1-01 --01
u-uu --uu
Register
Rev. 1.30
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Enhanced Flash Type 8-Bit MCU with EEPROM
Reset
(Power-on)
RES or LVR
Reset
WDT Time-out
(Normal Operation)
WDT Time-out
(IDLE)
PRM0
---- -000
---- -000
---- -000
---- -uuu
TM1C0
0000 0000
0000 0000
0000 0000
uuuu uuuu
TM1C1
0000 0000
0000 0000
0000 0000
uuuu uuuu
TM1C2
0000 0000
0000 0000
0000 0000
uuuu uuuu
TM1DL
0000 0000
0000 0000
0000 0000
uuuu uuuu
TM1DH
---- --00
---- --00
---- --00
---- --uu
TM1AL
0000 0000
0000 0000
0000 0000
uuuu uuuu
TM1AH
---- --00
---- --00
---- --00
---- --uu
TM1BL
0000 0000
0000 0000
0000 0000
uuuu uuuu
TM1BH
---- --00
---- --00
---- --00
---- --uu
SCOMC
0000 0000
0000 0000
0000 0000
uuuu uuuu
Register
Note: “ - ” stands for not implement
“ u ” stands for unchanged
“ x ” stands for unknown
Rev. 1.30
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May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
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.
These devices provide bidirectional input/output lines labeled with port names PA~PC 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 Port Register List
HT66F20-1/HT68F20-1 Register
Bit
Register
Name
7
6
5
4
3
2
1
0
PAWU
PAWU7
PAWU 6
PAWU5
PAWU4
PAWU3
PAWU2
PAWU1
PAWU0
PAPU
PAPU7
PAPU6
PAPU5
PAPU4
PAPU3
PAPU2
PAPU1
PAPU0
PA
PA7
PA6
PA5
PA4
PA3
PA2
PA1
PA0
PAC
PAC7
PAC6
PAC5
PAC4
PAC3
PAC2
PAC1
PAC0
PBPU
―
―
PBPU5
PBPU4
PBPU3
PBPU2
PBPU1
PBPU0
PB
—
—
PB5
PB4
PB3
PB2
PB1
PB0
PBC
—
—
PBC5
PBC4
PBC3
PBC2
PBC1
PBC0
PCPU0
PCPU
—
—
—
—
PCPU3
PCPU2
PCPU1
PC
—
—
—
—
PC3
PC2
PC1
PC0
PCC
—
—
—
—
PCC3
PCC2
PCC1
PCC0
HT66F30-1/HT68F30-1 Register
Bit
Register
Name
7
6
5
4
3
2
1
0
PAWU
PAWU7
PAWU 6
PAWU5
PAWU4
PAWU3
PAWU2
PAWU1
PAWU0
PAPU
PAPU7
PAPU6
PAPU5
PAPU4
PAPU3
PAPU2
PAPU1
PAPU0
PA
PA7
PA6
PA5
PA4
PA3
PA2
PA1
PA0
PAC
PAC7
PAC6
PAC5
PAC4
PAC3
PAC2
PAC1
PAC0
PBPU
—
—
PBPU5
PBPU4
PBPU3
PBPU2
PBPU1
PBPU0
PB
—
—
PB5
PB4
PB3
PB2
PB1
PB0
PBC
—
—
PBC5
PBC4
PBC3
PBC2
PBC1
PBC0
PCPU
PCPU7
PCPU6
PCPU5
PCPU4
PCPU3
PCPU2
PCPU1
PCPU0
PC
PC7
PC6
PC5
PC4
PC3
PC2
PC1
PC0
PCC
PCC7
PCC6
PCC5
PCC4
PCC3
PCC2
PCC1
PCC0
Rev. 1.30
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Enhanced Flash Type 8-Bit MCU with EEPROM
Pull-high Resistors
Many product applications require pull-high resistors for their switch inputs usually requiring the
use of an external resistor. To eliminate the need for these external resistors, all I/O pins, when
configured as an input have the capability of being connected to an internal pull-high resistor. These
pull-high resistors are selected using registers, namely PAPU~PCPU, and are implemented using
weak PMOS transistors.
PAPU Register
Bit
7
6
5
4
3
2
1
0
Name
PAPU7
PAPU6
PAPU5
PAPU4
PAPU3
PAPU2
PAPU1
PAPU0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
0
0
0
0
0
0
0
Bit
7
6
5
4
3
2
1
0
Name
—
—
PBPU5
PBPU4
PBPU3
PBPU2
PBPU1
PBPU0
R/W
—
—
R/W
R/W
R/W
R/W
R/W
R/W
POR
—
—
0
0
0
0
0
0
PBPU Register
PCPU Register
• HT66F20-1/HT68F20-1
Bit
7
6
5
4
3
2
1
0
Name
PCPU7
PCPU6
PCPU5
PCPU4
PCPU3
PCPU2
PCPU1
PCPU0
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
• HT66F30-1/HT68F30-1
Rev. 1.30
Bit
7
6
5
4
3
2
1
0
Name
—
—
—
—
PCPU3
PCPU2
PCPU1
PCPU0
R/W
—
—
—
—
R/W
R/W
R/W
R/W
POR
—
—
—
—
0
0
0
0
Bit 7~6
“—” Unimplemented, read as “0”
PAPUn/PBPUn/PCPUn: Pull-high function control
0: disable
1: enable
72
May 20, 2014
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Enhanced Flash Type 8-Bit MCU with EEPROM
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
PAWU7
PAWU6
PAWU5
PAWU4
PAWU3
PAWU2
PAWU1
PAWU0
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 7~0PAWU7~PAWU0: Port A wake-up control
0: Disable
1: Enable
I/O Port Control Registers
Each I/O port has its own control register known as PAC~PCC, to control the input/output
configuration. With this control register, each CMOS output or input can be reconfigured
dynamically under software control. Each pin of the I/O ports is directly mapped to a bit in its
associated port control register. For the I/O pin to function as an input, the corresponding bit of the
control register must be written as a “1”. This will then allow the logic state of the input pin to be
directly read by instructions. When the corresponding bit of the control register is written as a “0”,
the I/O pin will be setup as a CMOS output. If the pin is currently setup as an output, instructions
can still be used to read the output register. However, it should be noted that the program will in fact
only read the status of the output data latch and not the actual logic status of the output pin.
PAC Register
Bit
7
6
5
4
3
2
1
0
Name
PAC7
PAC6
PAC5
PAC4
PAC3
PAC2
PAC1
PAC0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
1
1
1
1
1
1
1
1
7
6
5
4
3
2
1
0
PBC Register
Bit
Rev. 1.30
Name
—
—
PBC5
PBC4
PBC3
PBC2
PBC1
PBC0
R/W
—
—
R/W
R/W
R/W
R/W
R/W
R/W
POR
—
—
1
1
1
1
1
1
73
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
PCC Register
• HT66F20-1/HT68F20-1
Bit
7
6
5
4
3
2
1
0
Name
—
—
—
—
PCC3
PCC2
PCC1
PCC0
R/W
—
—
—
—
R/W
R/W
R/W
R/W
POR
—
—
—
—
1
1
1
1
• HT66F30-1/HT68F30-1
Bit
7
6
5
4
3
2
1
0
Name
PCC7
PCC6
PCC5
PCC4
PCC3
PCC2
PCC1
PCC0
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 7~6
“—”: Unimplemented, read as “0”
PACn/PBCn/PCCn: I/O type selection
0: output
1: input
Pin-remapping Functions
The flexibility of the microcontroller range is greatly enhanced by the use of pins that have more
than one function. Limited numbers of pins can force serious design constraints on designers but
by supplying pins with multi-functions, many of these difficulties can be overcome. The way in
which the pin function of each pin is selected is different for each function and a priority order is
established where more than one pin function is selected simultaneously. Additionally there is a
PRM0 register to establish certain pin functions. This pin-remapping function is only available for
the HT66F30-1 and HT68F30-1 devices.
Pin-remapping Registers
The limited number of supplied pins in a package can impose restrictions on the amount of functions
a certain device can contain. However by allowing the same pins to share several different functions
and providing a means of function selection, a wide range of different functions can be incorporated
into even relatively small package sizes. The devices include a PRM0 register which can select the
functions of certain pins. The HT66F30-1 and HT68F30-1 devices include a PRM0 register which
can select the functions of certain pins.
PRM0 Register – HT66F30-1/HT68F30-1
Bit
7
6
5
4
3
2
1
0
Name
—
—
—
—
—
PCPRM
SIMPS0
PCKPS
R/W
—
—
—
—
—
R/W
R/W
R/W
POR
—
—
—
—
—
0
0
0
Bit 7~3
Unimplemented, read as “0”
Bit 2PCPRM: PC1~PC0 pin-shared function Pin Remapping Control
0: No change
1: TP1B_0 on PC0 change to PA6, TP1B_1 on PC1 change to PA7 if SIMPS0=1
Bit 1SIMPS0: SIM Pin Remapping Control
0: SDO on PA5; SDI/SDA on PA6; SCK/SCL on PA7; SCS on PB5
1: SDO on PC1; SDI/SDA on PC0; SCK/SCL on PC7; SCS on PC6
Bit 0PCKPS: PCK and PINT Pin Remapping Control
0: PCK on PC2; PINT on PC3
1: PCK on PC5; PINT on PC4
Rev. 1.30
74
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
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
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A/D Input/Output Structure
Rev. 1.30
75
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
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~PCC, 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~PC, 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.
Timer Modules – TM
One of the most fundamental functions in any microcontroller devices 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
either multiple 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 Enhanced TM sections.
Introduction
The devices contain two TMs having a reference name of TM0 and TM1. Each individual TM
can be categorised as a certain type, namely Compact Type TM, Standard Type TM or Enhanced
Type TM. Although similar in nature, the different TM types vary in their feature complexity.
The common features to all of the Compact, Standard and Enhanced 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 three types of TMs are summarised in the
accompanying table.
TM Function
CTM
STM
ETM
Timer/Counter
√
√
√
I/P Capture
—
√
√
Compare Match Output
√
√
√
PWM Channels
1
1
2
Single Pulse Output
PWM Alignment
PWM Adjustment Period & Duty
—
1
2
Edge
Edge
Edge & Centre
Duty or Period
Duty or Period
Duty or Period
TM Function Summary
Rev. 1.30
76
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
Each device in the series contains a specific number of Compact Type, Standard Type and Enhanced
Type TM which are shown in the table together with their individual reference name, TM0, TM1.
Device
TM0
TM1
HT66F20-1/HT68F20-1
10-bit CTM
10-bit STM
HT66F30-1/HT68F30-1
10-bit CTM
10-bit ETM
TM Name/Type Reference
TM Operation
The different types of TM offer a diverse range of functions, from simple timing operations to
PWM signal generation. The key to understanding how the TM operates is to see it in terms of
a free running counter whose value is then compared with the value of pre-programmed internal
comparators. When the free running counter has the same value as the pre-programmed comparator,
known as a compare match situation, a TM interrupt signal will be generated which can clear the
counter and perhaps also change the condition of the TM output pin. The internal TM counter is
driven by a user selectable clock source, which can be an internal clock or an external pin.
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 TMn
control registers. The clock source can be a ratio of either the system clock fSYS or the internal high
clock fH, the fL clock source or the external TCKn pin. Note that setting these bits to the value 101
will select an undefined clock input, in effect disconnecting the TM clock source. The TCKn pin
clock source is used to allow an external signal to drive the TM as an external clock source or for
event counting.
TM Interrupts
The Compact and Standard type TMs each has 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. As the Enhanced type TM has three internal comparators and comparator A or comparator
B or comparator P compare match functions, it consequently has three internal interrupts. 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.
Rev. 1.30
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Enhanced Flash Type 8-Bit MCU with EEPROM
TM External Pins
Each of the TMs, irrespective of what type, has one TM input pin, with the label TCKn. The TM
input pin, is essentially a clock source for the TM and is selected using the TnCK2~TnCK0 bits in
the TMnC0 register. This external TM input pin allows an external clock source to drive the internal
TM. This external TM input pin is shared with other functions but will be connected to the internal
TM if selected using the TnCK2~TnCK0 bits. The TM input pin can be chosen to have either a
rising or falling active edge.
The TMs each have one or more output pins with the label TPn. When the TM is in the Compare
Match Output Mode, these pins can be controlled by the TM to switch to a high or low level or to
toggle when a compare match situation occurs. The external TPn output pin is also the pin where
the TM generates the PWM output waveform. As the TM output pins are pin-shared with other
function, the TM output function must first be setup using registers. A single bit in one of the
registers determines if its associated pin is to be used as an external TM output pin or if it is to have
another function. The number of output pins for each TM type and devices are different, the details
are provided in the accompanying table.
All TM output pin names have a “_n” suffix. Pin names that include a “_0” or “_1” suffix indicate
that they are from a TM with multiple output pins. This allows the TM to generate a complimentary
output pair, selected using the I/O register data bits.
Device
CTM
STM
ETM
Registers
HT66F20-1
HT68F20-1
TCK0
TP0_0
TCK1
TP1_0, TP1_1
―
TMPC0
HT66F30-1
HT68F30-1
TCK0
TP0_0, TP0_1
―
TCK1
TP1A, TP1B_0, TP1B_1
TMPC0
TM Input/Output Pins
TM Input/Output Pin Control
Selecting to have a TM input/output or whether to retain its other shared function, is implemented
using one or two registers, with a single bit in each register corresponding to a TM input/output pin.
Setting the bit high will setup the corresponding pin as a TM input/output, if reset to zero the pin
will retain its original other function.
Device
Bit
7
6
5
4
3
2
1
0
HT66F20-1
HT68F20-1
—
—
T1CP1
T1CP0
—
—
—
T0CP0
HT66F30-1
HT68F30-1
T1ACP0
—
—
—
T0CP1
T0CP0
T1BCP1 T1BCP1
TM Input/Output Pin Control Registers List
Rev. 1.30
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HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
HT66F20-1/HT68F20-1 TM Function Pin Control Block Diagram
Note: 1. The I/O register data bits shown are used for TM output inversion control.
2. In the Capture Input Mode, the TM pin control register must never enable more than one
TM input.
Rev. 1.30
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HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
HT66F30-1/HT68F30-1 TM0 Function Pin Control Block Diagram
Note: 1. The I/O register data bits shown are used for TM output inversion control.
2. In the Capture Input Mode, the TM pin control register must never enable more than one
TM input.
HT66F30-1/HT68F30-1 TM1 Function Pin Control Block Diagram
Note: 1. The I/O register data bits shown are used for TM output inversion control.
2. In the Capture Input Mode, the TM pin control register must never enable more than one
TM input.
Rev. 1.30
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May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
TMPC0 Register
• HT66F20-1/HT68F20-1
Bit
7
6
5
4
3
2
1
0
Name
—
—
T1CP1
T1CP1
—
—
—
T0CP0
R/W
—
—
R/W
R/W
—
—
—
R/W
POR
—
—
0
1
—
—
—
1
3
2
1
0
Bit 7~6
“—” Unimplemented, read as “0”
Bit 5T1CP1: TP1_1 Pin Control
0: Disable
1: Enable
Bit 4T1CP0: TP1_0 Pin Control
0: Disable
1: Enable
Bit 3~1
“—” Unimplemented, read as “0”
Bit 0T0CP0: TP0_0 Pin Control
0: Disable
1: Enable
• HT66F30-1/HT68F30-1
Bit
7
6
5
4
Name
R/W
T1ACP0
—
T1BCP1
T1BCP0
—
—
T0CP1
T0CP0
R/W
—
R/W
R/W
—
—
R/W
POR
R/W
1
—
0
1
—
—
0
1
Bit 7T1ACP0: TP1A pin Control
0: Disable
1: Enable
Bit 6
Unimplemented, read as "0"
Bit 5T1BCP1: TP1B_1 pin Control
0: Disable
1: Enable
Bit 4T1BCP0: TP1B_0 pin Control
0: Disable
1: Enable
Bit 3~2
Unimplemented, read as "0"
Bit 1T0CP1: TP0_1 pin Control
0: Disable
1: Enable
Bit 0T0CP0: TP0_0 pin Control
0: Disable
1: Enable
Rev. 1.30
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HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
Programming Considerations
The TM Counter Registers and the Capture/Compare CCRA and CCRB registers, 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.
T� Counter Register (Read onl�)
T�xDL
T�xDH
8-bit
Buffer
T�xAL
T�xAH
T� CCRA Register (Read/Write)
T�xBL
T�xBH
T� CCRB Register (Read/Write)
Data
Bus
The following steps show the read and write procedures:
• Writing Data to CCRB or CCRA
♦♦
Step 1. Write data to Low Byte TMxAL or TMxBL
––Note that here data is only written to the 8-bit buffer.
♦♦
Step 2. Write data to High Byte TMxAH or TMxBH
––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 CCRB or CCRA
Rev. 1.30
♦♦
Step 1. Read data from the High Byte TMxDH, TMxAH or TMxBH
––Here data is read directly from the High Byte registers and simultaneously data is latched
from the Low Byte register into the 8-bit buffer.
♦♦
Step 2. Read data from the Low Byte TMxDL, TMxAL or TMxBL
––This step reads data from the 8-bit buffer.
82
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Enhanced Flash Type 8-Bit MCU with EEPROM
Compact Type TM – CTM
Although the simplest form of the two TM types, the Compact TM type still contains three operating
modes, which are Compare Match Output, Timer/Event Counter and PWM Output modes. The
Compact TM can also be controlled with an external input pin and can drive one or two external
output pins. The two external output pins can be the same signal or the inverse signal.
Device
TM Type
TM Name
TM Input Pin
HT66F20-1/HT68F20-1
10-bit CTM
TM0
TCK0
TM Output Pin
TP0_0
HT66F30-1/HT68F30-1
10-bit CTM
TM0
TCK0
TP0_0, TP0_1
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  ­ ­     Compact Type TM Block Diagram (n=0)
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 T0ON 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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Enhanced Flash Type 8-Bit MCU with EEPROM
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
TM0C0
T0PAU
T0CK2
T0CK1
T0CK0
T0ON
T0RP2
T0RP1
T0RP0
TM0C1
T0M1
T0M0
T0IO1
T0IO0
T0OC
T0POL
T0DPX
T0CCLR
D0
TM0DL
D7
D6
D5
D4
D3
D2
D1
TM0DH
—
—
—
—
—
—
D9
D8
TM0AL
D7
D6
D5
D4
D3
D2
D1
D0
TM0AH
—
—
—
—
—
—
D9
D8
Compact TM Register List
TM0DL Register
Bit
7
6
5
4
3
2
1
0
Name
D7
D6
D5
D4
D3
D2
D1
D0
R/W
R
R
R
R
R
R
R
R
POR
0
0
0
0
0
0
0
0
2
1
0
Bit 7~0TM0DL: TM0 Counter Low Byte Register bit 7~bit 0
TM0 10-bit Counter bit 7~bit 0
TM0DH Register
Bit
7
6
5
4
3
Name
—
—
—
—
—
—
D9
D8
R/W
—
—
—
—
—
—
R
R
POR
—
—
—
—
—
—
0
0
2
1
0
Bit 7~2
Unimplemented, read as "0"
Bit 1~0TM0DH: TM0 Counter High Byte Register bit 1~bit 0
TM0 10-bit Counter bit 9~bit 8
TM0AL Register
Bit
7
6
5
4
3
Name
D7
D6
D5
D4
D3
D2
D1
D0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
0
0
0
0
0
0
0
2
1
0
Bit 7~0TM0AL: TM0 CCRA Low Byte Register bit 7~bit 0
TM0 10-bit CCRA bit 7~bit 0
TM0AH Register
Bit
7
6
5
4
3
Name
—
—
—
—
—
—
D9
D8
R/W
—
—
—
—
—
—
R/W
R/W
POR
—
—
—
—
—
—
0
0
Bit 7~2
Unimplemented, read as "0"
Bit 1~0TM0AH: TM0 CCRA High Byte Register bit 1~bit 0
TM0 10-bit CCRA bit 9~bit 8
Rev. 1.30
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HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
TM0C0 Register
Bit
7
6
5
4
3
2
1
0
Name
T0PAU
T0CK2
T0CK1
T0CK0
T0ON
T0RP2
T0RP1
T0RP0
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 7T0PAU: TM0 Counter Pause Control
0: Run
1: Pause
The counter can be paused by setting this bit high. Clearing the bit to zero restores
normal counter operation. When in a Pause condition the TM will remain powered up
and continue to consume power. The counter will retain its residual value when this bit
changes from low to high and resume counting from this value when the bit changes
to a low value again.
Bit 6~4T0CK2~T0CK0: Select TM0 Counter clock
000: fSYS/4
001: fSYS
010: fH/16
011: fH/64
100: fTBC
101: Undefined
110: TCK0 rising edge clock
111: TCK0 falling edge clock
These three bits are used to select the clock source for the TM0. Selecting the
Reserved clock input will effectively disable the internal counter. The external pin
clock source can be chosen to be active on the rising or falling edge. The clock source
fSYS is the system clock, while fH and fTBC are other internal clocks, the details of which
can be found in the oscillator section.
Bit 3T0ON: TM0 Counter On/Off Control
0: Off
1: On
This bit controls the overall on/off function of the TM0. Setting the bit high enables
the counter to run, clearing the bit disables the TM0. Clearing this bit to zero will
stop the counter from counting and turn off the TM0 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 TM0 is in the Compare Match Output
Mode then the TM0 output pin will be reset to its initial condition, as specified by the
T0OC bit, when the T0ON bit changes from low to high.
Bit 2~0T0RP2~T0RP0: TM0 CCRP 3-bit register, compared with the TM0 Counter bit 9~bit 7
Comparator P Match Period
000: 1024 TM0 clocks
001: 128 TM0 clocks
010: 256 TM0 clocks
011: 384 TM0 clocks
100: 512 TM0 clocks
101: 640 TM0 clocks
110: 768 TM0 clocks
111: 896 TM0 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 T0CCLR bit is set to
zero. Setting the T0CCLR bit to zero ensures that a compare match with the CCRP
values will reset the internal counter. As the CCRP bits are only compared with the
highest three counter bits, the compare values exist in 128 clock cycle multiples.
Clearing all three bits to zero is in effect allowing the counter to overflow at its
maximum value.
Rev. 1.30
85
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
TM0C1 Register
Bit
7
6
5
4
3
2
1
0
Name
T0M1
T0M0
T0IO1
T0IO0
T0OC
T0POL
T0DPX
T0CCLR
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
0
0
0
0
0
0
0
Bit 7~6T0M1~T0M0: Select TM0 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 T0M1 and T0M0
bits. In the Timer/Counter Mode, the TM output pin control must be disabled.
Bit 5~4T0IO1~T0IO0: Select TP0_0, TP0_1 output function
Compare Match Output Mode
00: No change
01: Output low
10: Output high
11: Toggle output
PWM Mode
00: PWM Output inactive state
01: PWM Output active state
10: PWM output
11: Undefined
Timer/counter Mode
unused
These two bits are used to determine how the TM0 output pin changes state when a
certain condition is reached. The function that these bits select depends upon in which
mode the TM0 is running.
In the Compare Match Output Mode, the T0IO1 and T0IO0 bits determine how the
TM0 output pin changes state when a compare match occurs from the Comparator A.
The TM0 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 TM0 output
pin should be setup using the T0OC bit in the TM0C1 register. Note that the output
level requested by the T0IO1 and T0IO0 bits must be different from the initial value
setup using the T0OC bit otherwise no change will occur on the TM0 output pin when
a compare match occurs. After the TM0 output pin changes state it can be reset to its
initial level by changing the level of the T0ON bit from low to high.
In the PWM Mode, the T0IO1 and T0IO0 bits determine how the TM output pin
changes state when a certain compare match condition occurs. The PWM output
function is modified by changing these two bits. It is necessary to only change
the values of the T0IO1 and T0IO0 bits only after the TM0 has been switched off.
Unpredictable PWM outputs will occur if the T0IO1 and T0IO0 bits are changed when
the TM is running.
Rev. 1.30
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May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
Bit 3T0OC: TP0_0, TP0_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 TM0 output pin. Its operation depends upon
whether TM0 is being used in the Compare Match Output Mode or in the PWM Mode.
It has no effect if the TM0 is in the Timer/Counter Mode. In the Compare Match
Output Mode it determines the logic level of he TM0 output pin before a compare
match occurs. In the PWM Mode it determines if the PWM signal is active high or
active low.
Bit 2T0POL: TP0_0, TP0_1 Output polarity Control
0: Non-invert
1: Invert
This bit controls the polarity of the TP0_0 or TP0_1 output pin. When the bit is set
high the TM0 output pin will be inverted and not inverted when the bit is zero. It has
no effect if the TM0 is in the Timer/Counter Mode.
Bit 1T0DPX: TM0 PWM period/duty Control
0: CCRP - period; CCRA - duty
1: CCRP - duty; CCRA - period
This bit, determines which of the CCRA and CCRP registers are used for period and
duty control of the PWM waveform.
Bit 0T0CCLR: Select TM0 Counter clear condition
0: TM0 Comparator P match
1: TM0 Comparator A match
This bit is used to select the method which clears the counter. Remember that the
Compact TM0 contains two comparators, Comparator A and Comparator P, either of
which can be selected to clear the internal counter. With the T0CCLR bit set high,
the counter will be cleared when a compare match occurs from the Comparator A.
When the bit is low, the counter will be cleared when a compare match occurs from
the Comparator P or with a counter overflow. A counter overflow clearing method can
only be implemented if the CCRP bits are all cleared to zero. The T0CCLR bit is not
used in the PWM Mode.
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 T0M1 and T0M0
bits in the TM0C1 register.
Compare Match Output Mode
To select this mode, bits T0M1 and T0M0 in the TM0C1 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 T0CCLR 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 T0AF and T0PF interrupt request flags for the Comparator A and
Comparator P respectively, will both be generated.
Rev. 1.30
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May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
If the T0CCLR bit in the TM0C1 register is high then the counter will be cleared when a compare
match occurs from Comparator A. However, here only the T0AF interrupt request flag will be
generated even if the value of the CCRP bits is less than that of the CCRA registers. Therefore when
T0CCLR is high no T0PF 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 T0AF
interrupt request flag will not be generated.
As the name of the mode suggests, after a comparison is made, the TM output pin will change
state. The TM output pin condition however only changes state when a T0AF interrupt request flag
is generated after a compare match occurs from Comparator A. The T0PF 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
T0IO1 and T0IO0 bits in the TM0C1 register. The TM output pin can be selected using the T0IO1
and T0IO0 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
T0ON bit changes from low to high, is setup using the T0OC bit. Note that if the T0IO1 and T0IO0
bits are zero then no pin change will take place.
Counter Value
Counter overflow
CCRP=0
0x3FF
TnCCLR = 0; Tn� [1:0] = 00
CCRP > 0
Counter cleared b� CCRP value
CCRP > 0
Counter
Restart
Resume
CCRP
Pause
CCRA
Stop
Time
TnON
TnPAU
TnPOL
CCRP Int.
Flag TnPF
CCRA Int.
Flag TnAF
T� O/P Pin
Output pin set to
initial Level Low
if TnOC=0
Output not affected b� TnAF
flag. Remains High until reset
b� 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 b�
other pin-shared function
Compare Match Output Mode – TnCCLR=0
Note: 1. With TnCCLR=0, a Comparator P match will clear the counter
2. The TM output pin is controlled only by the TnAF flag
3. The output pin is reset to its initial state by a TnON bit rising edge
4. n=0
Rev. 1.30
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HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
Counter Value
TnCCLR = 1; TnM [1:0] = 00
CCRA = 0
Counter overflow
CCRA > 0 Counter cleared by CCRA value
0x3FF
CCRA=0
Resume
CCRA
Pause
Stop
Counter Restart
CCRP
Time
TnON
TnPAU
TnPOL
No TnAF flag
generated on
CCRA overflow
CCRA Int.
Flag TnAF
CCRP Int.
Flag TnPF
TnPF not
generated
Output does
not change
TM O/P Pin
Output pin set to
initial Level Low
if TnOC=0
Output not affected by
TnAF flag. Remains High
until reset by TnON bit
Output Toggle with
TnAF flag
Here TnIO [1:0] = 11
Toggle Output select
Note TnIO [1:0] = 10
Active High Output select
Output Inverts
when TnPOL is high
Output Pin
Reset to Initial value
Output controlled by
other pin-shared function
Compare Match Output Mode – TnCCLR=1
Note: 1. With TnCCLR=1, a Comparator A match will clear the counter
2. The TM output pin is controlled only by the TnAF flag
3. The output pin is reset to its initial state by a TnON bit rising edge
4. The TnPF flag is not generated when TnCCLR=1
5. n=0
Rev. 1.30
89
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
Timer/Counter Mode
To select this mode, bits T0M1 and T0M0 in the TM0C1 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 T0M1 and T0M0 in the TM0C1 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 T0CCLR 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 T0DPX bit in the TM0C1 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 T0OC bit in the TM0C1 register is used to
select the required polarity of the PWM waveform while the two T0IO1 and T0IO0 bits are used to
enable the PWM output or to force the TM output pin to a fixed high or low level. The T0POL bit is
used to reverse the polarity of the PWM output waveform.
CTM, PWM Mode, Edge-aligned Mode, T0DPX=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, T0DPX=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.
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Enhanced Flash Type 8-Bit MCU with EEPROM
Counter Value
TnDPX = 0; TnM [1:0] = 10
Counter cleared
by CCRP
Counter Reset when
TnON returns high
CCRP
Pause Resume
CCRA
Counter Stop if
TnON bit low
Time
TnON
TnPAU
TnPOL
CCRA Int.
Flag TnAF
CCRP Int.
Flag TnPF
TM O/P Pin
(TnOC=1)
TM O/P Pin
(TnOC=0)
PWM Duty Cycle
set by CCRA
PWM Period
set by CCRP
PWM resumes
operation
Output controlled by
Output Inverts
other pin-shared function
when TnPOL = 1
PWM Mode – TnDPX=0
Note: 1. Here TnDPX=0 – Counter cleared by CCRP
2. A counter clear sets the PWM Period
3. The internal PWM function continues even when TnIO [1:0]=00 or 01
4. The TnCCLR bit has no influence on PWM operation
5. n=0
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Enhanced Flash Type 8-Bit MCU with EEPROM
Counter Value
TnDPX = 1; TnM [1:0] = 10
Counter cleared
by CCRA
Counter Reset when
TnON returns high
CCRA
Pause Resume
CCRP
Counter Stop if
TnON bit low
Time
TnON
TnPAU
TnPOL
CCRP Int.
Flag TnPF
CCRA Int.
Flag TnAF
TM O/P Pin
(TnOC=1)
TM O/P Pin
(TnOC=0)
PWM Duty Cycle
set by CCRP
PWM Period
set by CCRA
PWM resumes
operation
Output controlled by
Output Inverts
other pin-shared function
when TnPOL = 1
PWM Mode – TnDPX=1
Note: 1. Here TnDPX=1 – Counter cleared by CCRA
2. A counter clear sets the PWM Period
3. The internal PWM function continues even when TnIO [1:0]=00 or 01
4. The TnCCLR bit has no influence on PWM operation
5. n=0
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Enhanced Flash Type 8-Bit MCU with EEPROM
Standard Type TM – STM
The Standard Type TM contains five operating modes, which are Compare Match Output, Timer/
Event Counter, Capture Input, Single Pulse Output and PWM Output modes. The Standard TM can
also be controlled with an external input pin and can drive two external output pins. The Standard
Type TM is only contained in the HT66F20-1 and HT68F20-1 devices.
Device
TM Type
TM Name
TM Input Pin
TM Output Pin
HT66F20-1/HT68F20-1
10-bit STM
TM1
TCK1
TP1_0, TP1_1
HT66F30-1/HT68F30-1
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‚   HT66F20-1/HT68F20-1 Standard Type TM Block Diagram (n=1)
Standard TM Operation
At the 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 comparator is 3-bit wide whose value is compared the with highest 3 bits in the counter while
the CCRA is the ten or sixteen bits and therefore compares all counter bits.
The only way of changing the value of the 10-bit counter using the application program, is to
clear the counter by changing the TnON bit from low to high. The counter will also be cleared
automatically by a counter overflow or a compare match with one of its associated comparators.
When these conditions occur, a TM interrupt signal will also usually be generated. The Standard
Type TM can operate in a number of different operational modes, can be driven by different clock
sources including an input pin and can also control an output pin. All operating setup conditions are
selected using relevant internal registers.
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Standard Type TM Register Description
Overall operation of the Standard TM is controlled using a series of registers. A read only register
pair exists to store the internal counter 10-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
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
TM1C0
T1PAU
T1CK2
T1CK1
T1CK0
T1ON
T1RP2
T1RP1
T1RP0
TM1C1
T1M1
T1M0
T1IO1
T1IO0
T1OC
T1POL
T1DPX
T1CCLR
TM1DL
D7
D6
D5
D4
D3
D2
D1
D0
TM1DH
D15
D14
D13
D12
D11
D10
D9
D8
TM1AL
D7
D6
D5
D4
D3
D2
D1
D0
TM1AH
D15
D14
D13
D12
D11
D10
D9
D8
10-bit Standard TM Register List – HT66F20-1/HT68F20-1
TM1C0 Register
Bit
7
6
5
4
3
2
1
0
Name
T1PAU
T1CK2
T1CK1
T1CK0
T1ON
T1RP2
T1RP1
T1RP0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
0
0
0
0
0
0
0
Bit 7T1PAU: TM1 Counter Pause Control
0: Run
1: Pause
The counter can be paused by setting this bit high. Clearing the bit to zero restores
normal counter operation. When in a Pause condition the TM will remain powered up
and continue to consume power. The counter will retain its residual value when this bit
changes from low to high and resume counting from this value when the bit changes
to a low value again.
Bit 6~4T1CK2, T1CK1, T1CK0: Select TM1 Counter clock
000: fSYS/4
001: fSYS
010: fH/16
011: fH/64
100: fTBC
101: Undefined
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 fTBC are other internal clocks, the details of which can be
found in the oscillator section.
Bit 3T1ON: TM1 Counter On/Off Control
0: Off
1: On
This bit controls the overall on/off function of the TM. Setting the bit high enables the
counter to run, clearing the bit disables the TM. Clearing this bit to zero will stop the
counter from counting and turn off the TM which will reduce its power consumption.
When the bit changes state from low to high the internal counter value will be reset to
zero, however when the bit changes from high to low, the internal counter will retain
its residual value until the bit returns high again. If the TM is in the Compare Match
Output Mode then the TM output pin will be reset to its initial condition, as specified
by the T1OC bit, when the T1ON bit changes from low to high.
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Enhanced Flash Type 8-Bit MCU with EEPROM
Bit 2~0
T1RP2~T1RP0: TM1 CCRP 3-bit register, compared with the TM1 Counter bit 9~bit 7
Comparator P Match Period
000: 1024 TM1 clocks
001: 128 TM1 clocks
010: 256 TM1 clocks
011: 384 TM1 clocks
100: 512 TM1 clocks
101: 640 TM1 clocks
110: 768 TM1 clocks
111: 896 TM1 clocks
These three bits are used to setup the value on the internal CCRP 3-bit register, which
are then compared with the internal counter's highest three bits. The result of this
comparison can be selected to clear the internal counter if the T1CCLR bit is set to
zero. Setting the T1CCLR bit to zero ensures that a compare match with the CCRP
values will reset the internal counter. As the CCRP bits are only compared with the
highest three counter bits, the compare values exist in 128 clock cycle multiples.
Clearing all three bits to zero is in effect allowing the counter to overflow at its
maximum value.
TM1C1 Register
Bit
7
6
5
4
3
2
1
0
Name
T1M1
T1M0
T1IO1
T1IO0
T1OC
T1POL
T1DPX
T1CCLR
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
0
0
0
0
0
0
0
Bit 7~6T1M1~T1M0: Select TM1 Operating Mode
00: Compare Match Output Mode
01: Capture Input Mode
10: PWM Mode or Single Pulse Output Mode
11: Timer/Counter Mode
These bits setup the required operating mode for the TM. To ensure reliable operation
the TM should be switched off before any changes are made to the T1M1 and T1M0
bits. In the Timer/Counter Mode, the TM output pin control must be disabled.
Bit 5~4T1IO1~T1IO0: Select TP1_0, TP1_1 output function
Compare Match Output Mode
00: No change
01: Output low
10: Output high
11: Toggle output
PWM Mode/Single Pulse Output Mode
00: PWM output inactive state
01: PWM output active state
10: PWM output
11: Single pulse output
Capture Input Mode
00: Input capture at rising edge of TP1_0, TP1_1
01: Input capture at falling edge of TP1_0, TP1_1
10: Input capture at falling/rising edge of TP1_0, TP1_1
11: Input capture disabled
Timer/counter Mode:
Unused
These two bits are used to determine how the TM output pin changes state when a
certain condition is reached. The function that these bits select depends upon in which
mode the TM is running.
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In the Compare Match Output Mode, the T1IO1 and T1IO0 bits determine how the
TM output pin changes state when a compare match occurs from the Comparator A.
The TM output pin can be setup to switch high, switch low or to toggle its present
state when a compare match occurs from the Comparator A. When the bits are both
zero, then no change will take place on the output. The initial value of the TM output
pin should be setup using the T1OC bit in the TM1C1 register. Note that the output
level requested by the T1IO1 and T1IO0 bits must be different from the initial value
setup using the T1OC bit otherwise no change will occur on the TM output pin when
a compare match occurs. After the TM output pin changes state, it can be reset to its
initial level by changing the level of the T1ON bit from low to high.
In the PWM Mode, the T1IO1 and T1IO0 bits determine how the TM output pin
changes state when a certain compare match condition occurs. The PWM output
function is modified by changing these two bits. It is necessary to change the values
of the T1IO1 and T1IO0 bits only after the TM has been switched off. Unpredictable
PWM outputs will occur if the T1IO1 and T1IO0 bits are changed when the TM is
running.
Bit 3T1OC: TP1_0, TP1_1 Output control bit
Compare Match Output Mode
0: Initial low
1: Initial high
PWM Mode/Single Pulse Output Mode
0: Active low
1: Active high
This is the output control bit for the TM output pin. Its operation depends upon
whether TM is being used in the Compare Match Output Mode or in the PWM Mode/
Single Pulse Output Mode. It has no effect if the TM is in the Timer/Counter Mode. In
the Compare Match Output Mode it determines the logic level of the TM output pin
before a compare match occurs. In the PWM Mode it determines if the PWM signal is
active high or active low.
Bit 2TnPOL: TP1_0, TP1_1 Output polarity Control
0: Non-invert
1: Invert
This bit controls the polarity of the TP1_0 or TP1_1 output pin. When the bit is set
high the TM output pin will be inverted and not inverted when the bit is zero. It has no
effect if the TM is in the Timer/Counter Mode.
Bit 1T1DPX: TM1 PWM period/duty Control
0: CCRP - period; CCRA - duty
1: CCRP - duty; CCRA - period
This bit, determines which of the CCRA and CCRP registers are used for period and
duty control of the PWM waveform.
Bit 0T1CCLR: Select TM1 Counter clear condition
0: TM1 Comparatror P match
1: TM1 Comparatror A match
This bit is used to select the method which clears the counter. Remember that the
Standard TM contains two comparators, Comparator A and Comparator P, either of
which can be selected to clear the internal counter. With the T1CCLR bit set high,
the counter will be cleared when a compare match occurs from the Comparator A.
When the bit is low, the counter will be cleared when a compare match occurs from
the Comparator P or with a counter overflow. A counter overflow clearing method can
only be implemented if the CCRP bits are all cleared to zero. The T1CCLR bit is not
used in the PWM, Single Pulse or Input Capture Mode.
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Enhanced Flash Type 8-Bit MCU with EEPROM
TMnDL Register
Bit
7
6
5
4
3
2
1
0
Name
D7
D6
D5
D4
D3
D2
D1
D0
R/W
R
R
R
R
R
R
R
R
POR
0
0
0
0
0
0
0
0
Bit 7~0TM1DL: TM1 Counter Low Byte Register bit 7~bit 0
TM1 10-bit Counter bit 7~bit 0
TMnDH Register
Bit
7
6
5
4
3
2
1
0
Name
—
—
—
—
—
—
D9
D8
R/W
—
—
—
—
—
—
R
R
POR
—
—
—
—
—
—
0
0
2
1
0
Bit 7~2
Unimplemented, read as “0”
Bit 1~0TM1DH: TM1 Counter High Byte Register bit 1~bit 0
TM1 10-bit Counter bit 9~bit 8
TMnAL Register
Bit
7
6
5
4
3
Name
D7
D6
D5
D4
D3
D2
D1
D0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
0
0
0
0
0
0
0
Bit 7~0TM1AL: TM1 CCRA Low Byte Register bit 7~bit 0
TM1 10-bit CCRA bit 7~bit 0
TMnAH Register
Bit
7
6
5
4
3
2
1
0
Name
—
—
—
—
—
—
D1
D0
R/W
—
—
—
—
—
—
R/W
R/W
POR
—
—
—
—
—
—
0
0
Bit 7~2
Unimplemented, read as “0”
Bit 1~0TM1AH: TM1 CCRA High Byte Register bit 1~bit 0
TM1 10-bit CCRA bit 9~bit 8
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Enhanced Flash Type 8-Bit MCU with EEPROM
Standard Type TM Operating Modes
The Standard Type TM can operate in one of five operating modes, Compare Match Output Mode,
PWM Output Mode, Single Pulse Output Mode, Capture Input Mode or Timer/Counter Mode. The
operating mode is selected using the T1M1 and T1M0 bits in the TM1C1 register.
Compare Match Output Mode
To select this mode, bits T1M1 and T1M0 in the TM1C1 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 T1CCLR bit is low, there are two ways in which the counter can be cleared. One is when
a compare match from Comparator P, the other is when the CCRP bits are all zero which allows
the counter to overflow. Here both T1AF and T1PF interrupt request flags for Comparator A and
Comparator P respectively, will both be generated.
If the T1CCLR bit in the TM1C1 register is high then the counter will be cleared when a compare
match occurs from Comparator A. However, here only the T1AF interrupt request flag will be
generated even if the value of the CCRP bits is less than that of the CCRA registers. Therefore when
T1CCLR is high no T1PF interrupt request flag will be generated. In the Compare Match Output
Mode, the CCRA can not be set to "0".
As the name of the mode suggests, after a comparison is made, the TM output pin, will change
state. The TM output pin condition however only changes state when an T1AF interrupt request
flag is generated after a compare match occurs from Comparator A. The T1PF 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
T1IO1 and T1IO0 bits in the TM1C1 register. The TM output pin can be selected using the T1IO1
and T1IO0 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
T1ON bit changes from low to high, is setup using the T1OC bit. Note that if the T1IO1 and T1IO0
bits are zero then no pin change will take place.
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Enhanced Flash Type 8-Bit MCU with EEPROM
Counter Value
Counter overflow
CCRP=0
0x3FF
TnCCLR = 0; Tn� [1:0] = 00
CCRP > 0
Counter cleared b� CCRP value
CCRP > 0
Counter
Restart
Resume
CCRP
Pause
CCRA
Stop
Time
TnON
TnPAU
TnPOL
CCRP Int.
Flag TnPF
CCRA Int.
Flag TnAF
T� O/P Pin
Output pin set to
initial Level Low
if TnOC=0
Output not affected b� TnAF
flag. Remains High until reset
b� 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 b�
other pin-shared function
Compare Match Output Mode – TnCCLR=0
Note: 1. With TnCCLR=0, a Comparator P match will clear the counter
2. The TM output pin is controlled only by the TnAF flag
3. The output pin is reset to its initial state by a TnON bit rising edge
4. n=1
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Enhanced Flash Type 8-Bit MCU with EEPROM
Counter Value
TnCCLR = 1; Tn� [1:0] = 00
CCRA = 0
Counter overflow
CCRA > 0 Counter cleared b� 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
T� O/P Pin
Output pin set to
initial Level Low
if TnOC=0
Output not affected b�
TnAF flag. Remains High
until reset b� 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 b�
other pin-shared function
Compare Match Output Mode – TnCCLR=1
Note: 1. With TnCCLR=1, a Comparator A match will clear the counter
2. The TM output pin is controlled only by the TnAF flag
3. The output pin is reset to its initial state by a TnON bit rising edge
4. A TnPF flag is not generated when TnCCLR=1
5. n=1
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Enhanced Flash Type 8-Bit MCU with EEPROM
Timer/Counter Mode
To select this mode, bits T1M1 and T1M0 in the TM1C1 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 T1M1 and T1M0 in the TM1C1 register should be set to 10 respectively
and also the T1IO1 and T1IO0 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 T1CCLR bit has no effect as the PWM
period. Both of the CCRAand 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 T1DPX bit in the TM1C1 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 T1OC bit in the TM1C1 register is used to
select the required polarity of the PWM waveform while the two T1IO1 and T1IO0 bits are used to
enable the PWM output or to force the TM output pin to a fixed high or low level. The T1POL bit is
used to reverse the polarity of the PWM output waveform.
10-bit STM, PWM Mode, Edge-aligned Mode, T1DPX=0
CCRP
001b
010b
011b
100b
101b
110b
111b
000b
Period
128
256
384
512
640
768
896
1024
Duty
CCRA
If fSYS=12MHz, TM clock source select fSYS/4, CCRP = 100b, CCRA = 128
The STM PWM output frequency = (fSYS/4) / 512 = fSYS/2048 = 5.8594kHz, duty = 128/512 = 25%.
If the Duty value defined by CCRA or CCRB register is equal to or greater than the Period value,
then the PWM output duty is 100%.
10-bit STM, PWM Mode, Edge-aligned Mode, T1DPX=1
CCRP
001b
010b
011b
100b
Period
Duty
101b
110b
111b
000b
768
896
1024
CCRA
128
256
384
512
640
The PWM output period is determined by the CCRAregister value together with the TM clock while
the PWM duty cycle is defined by the CCRP register value.
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Enhanced Flash Type 8-Bit MCU with EEPROM
Counter Value
TnDPX = 0; Tn� [1:0] = 10
Counter cleared
b� 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
T� O/P Pin
(TnOC=1)
T� O/P Pin
(TnOC=0)
PW� Dut� C�cle
set b� CCRA
PW� Period
set b� CCRP
PW� resumes
operation
Output controlled b�
Output Inverts
other pin-shared function
when TnPOL = 1
PWM Mode – TnDPX=0
Note: 1. Here TnDPX=0, Counter cleared by CCRP
2. A counter clear sets the PWM Period
3. The internal PWM function continues running even when TnIO [1:0]=00 or 01
4. The TnCCLR bit has no influence on PWM operation
5. n=1
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102
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
Counter Value
TnDPX = 1; Tn� [1:0] = 10
Counter cleared
b� CCRA
Counter Reset when
TnON returns high
CCRA
Pause Resume
CCRP
Counter Stop if
TnON bit low
Time
TnON
TnPAU
TnPOL
CCRP Int.
Flag TnPF
CCRA Int.
Flag TnAF
T� O/P Pin
(TnOC=1)
T� O/P Pin
(TnOC=0)
PW� Dut� C�cle
set b� CCRP
PW� Period
set b� CCRA
PW� resumes
operation
Output controlled b�
Output Inverts
other pin-shared function
when TnPOL = 1
PWM Mode – TnDPX=1
Note: 1. Here TnDPX=1 -- Counter cleared by CCRA
2. A counter clear sets the PWM Period
3. The internal PWM function continues running even when TnIO [1:0]=00 or 01
4. The TnCCLR bit has no influence on PWM operation
5. n=1
Rev. 1.30
103
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
Single Pulse Mode
To select this mode, bits T1M1 and T1M0 in the TM1C1 register should be set to 10 respectively
and also the T1IO1 and T1IO0 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 T1ON bit, which can
be implemented using the application program. However in the Single Pulse Mode, the T1ON bit
can also be made to automatically change from low to high using the external TCK1 pin, which will
in turn initiate the Single Pulse output. When the T1ON bit transitions to a high level, the counter
will start running and the pulse leading edge will be generated. The T1ON bit should remain high
when the pulse is in its active state. The generated pulse trailing edge will be generated when the
T1ON 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 T1ON bit and thus
generate the Single Pulse output trailing edge. In this way the CCRA value can be used to control
the pulse width. A compare match from Comparator A will also generate a TM interrupt. The counter
can only be reset back to zero when the T1ON bit changes from low to high when the counter
restarts. In the Single Pulse Mode CCRP is not used. The T1CCLR and T1nDPX bits are not used in
this Mode.
            Single Pulse Generation
Rev. 1.30
104
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
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
Note: 1. Counter stopped by CCRA
2. CCRP is not used
3. The pulse triggered by the TCKn pin or by setting the TnON bit high
4. A TCKn pin active edge will automatically set the TnON bit high
5. In the Single Pulse Mode, TnIO [1:0] must be set to “11” and can not be changed
6. n=1
Rev. 1.30
105
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
Capture Input Mode
To select this mode bits T1M1 and T1M0 in the TM1C1 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 TP1_0 or TP1_1 pin, whose active edge can be a rising edge, a falling edge or both
rising and falling edges; the active edge transition type is selected using the T1IO1 and T1IO0 bits
in the TM1C1 register. The counter is started when the T1ON bit changes from low to high which is
initiated using the application program.
When the required edge transition appears on the TP1_0 or TP1_1 pin the present value in the
counter will be latched into the CCRA registers and a TM interrupt generated. Irrespective of what
events occur on the TP1_0 or TP1_1 pin the counter will continue to free run until the T1ON 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 T1IO1 and T1IO0 bits can select the active trigger edge on the TP1_0 or TP1_1
pin to be a rising edge, falling edge or both edge types. If the T1IO1 and T1IO0 bits are both set
high, then no capture operation will take place irrespective of what happens on the TP1_0 or TP1_1
pin, however it must be noted that the counter will continue to run.
As the TP1_0 or TP1_1 pin is pin shared with other functions, care must be taken if the TM is in the
Input Capture Mode. This is because if the pin is setup as an output, then any transitions on this pin
may cause an input capture operation to be executed. The T1CCLR and T1DPX bits are not used in
this Mode.
Tn� [1:0] = 01
Counter
Value
Counter
overflow
CCRP
Stop
Counter
Reset
YY
XX
Pause Resume
Time
TnON
edge
TnPAU
T� Capture
Pin TPn_x
Active
edge
Active
edge
Active
CCRA Int.
Flag TnAF
CCRP Int.
Flag TnPF
CCRA
Value
TnIO [1:0]
Value
XX
00 - Rising edge
YY
01 - Falling edge
XX
YY
10 - Both edges
11 - Disable Capture
Capture Input Mode
Note: 1. TnM [1:0]=01 and active edge set by the TnIO [1:0] bits
2. A TM Capture input pin active edge transfers the counter value to CCRA
3. TnCCLR bit not used
4. No output function - TnOC and TnPOL bits are not used
5. CCRP determines the counter value and the counter has a maximum count value when CCRP is equal to
zero.
6. n=1; x=0 or 1.
Rev. 1.30
106
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
Enhanced Type TM – ETM
The Enhanced Type TM contains five operating modes, which are Compare Match Output,
Timer/Event Counter, Capture Input, Single Pulse Output and PWM Output modes. The Enhanced
TM can also be controlled with an external input pin and can drive three external output pins.
CTM
Name
TM No.
TM Input Pin
TM Output Pin
HT66F20-1/HT68F20-1
―
―
―
―
HT66F30-1/HT68F30-1
10-bit ETM
TM1
TCK1
TP1A; TP1B_0, TP1B_1
†‡
ˆ ‡
†‡
‰
ˆ ‡
†Š  ‹
†Š ‹ ‰
† Œ  Ž  ‘  ‚
­            
 …

„ ­
„ ­
­  
  Œ ­  
  Œ ’ Œ ’ ­   ­
„ ­
€ ‚ ƒ 
   Œ Œ
  
 …

Œ „ Œ Œ ­
„ Œ ­
Œ Œ Œ ­   Œ
€ ‚ ƒ 
   Œ ­
„ Œ ­
Enhanced Type TM Block Diagram (n=1)
Enhanced TM Operation
At its core is a 10-bit count-up/count-down counter which is driven by a user selectable internal
or external clock source. There are three internal comparators with the names, Comparator A,
Comparator B and Comparator P. These comparators will compare the value in the counter with the
CCRA, CCRB and CCRP registers. The CCRP comparator is 3-bits wide whose value is compared
with the highest 3-bits in the counter while CCRA and CCRB are 10-bits wide and therefore
compared 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 T1ON 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 Enhanced
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 output pins. All operating setup conditions are
selected using relevant internal registers.
Rev. 1.30
107
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
Enhanced Type TM Register Description
Overall operation of the Enhanced 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 CCRB value. The remaining three 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
TM1C0
T1PAU
T1CK2
T1CK1
T1CK0
T1ON
T1RP2
T1RP1
T1RP0
TM1C1
T1AM1
T1AM0
T1AIO1
T1AIO0
T1AOC
T1PAOL
T1CDN
T1CCLR
TM1C2
T1BM1
T1BM0
T1BIO1
T1BIO0
T1BOC
T1PBOL
TM1DL
D7
D6
D5
D4
D3
D2
D1
TM1DH
—
—
—
—
—
—
D9
D8
TM1AL
D7
D6
D5
D4
D3
D2
D1
D0
T1PWM1 T1PWM0
D0
TM1AH
—
—
—
—
—
—
D9
D8
TM1BL
D7
D6
D5
D4
D3
D2
D1
D0
TM1BH
—
—
—
—
—
—
D9
D8
10-bit Enhanced TM Register List – HT66F30-1/HT68F30-1
TM1C0 Register – 10-bit ETM
Bit
7
6
5
4
3
2
1
0
Name
T1PAU
T1CK2
T1CK1
T1CK0
T1ON
T1RP2
T1RP1
T1RP0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
0
0
0
0
0
0
0
Bit 7T1PAU: TM1 Counter Pause Control
0: Run
1: Pause
The counter can be paused by setting this bit high. Clearing the bit to zero restores
normal counter operation. When in a Pause condition the TM will remain powered up
and continue to consume power. The counter will retain its residual value when this bit
changes from low to high and resume counting from this value when the bit changes
to a low value again.
Bit 6~4T1CK2~T1CK0: Select TM1 Counter clock
000: fSYS/4
001: fSYS
010: fH/16
011: fH/64
100: fTBC
101: Reserved
110: TCK1 rising edge clock
111: TCK1 falling edge clock
These three bits are used to select the clock source for the TM. Selecting the Reserved
clock input will effectively disable the internal counter. The external pin clock source
can be chosen to be active on the rising or falling edge. The clock source fSYS is the
system clock, while fH and fTBC are other internal clocks, the details of which can be
found in the oscillator section.
Rev. 1.30
108
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
Bit 3T1ON: TM1 Counter On/Off Control
0: Off
1: On
This bit controls the overall on/off function of the TM. Setting the bit high enables
the counter to run and clearing the bit disables the TM. Clearing this bit to zero will
stop the counter from counting and turn off the TM which will reduce its power
consumption. When the bit changes state from low to high the internal counter value
will be reset to zero, however when the bit changes from high to low, the internal
counter will retain its residual value until the bit returns high again.
If the TM is in the Compare Match Output Mode then the TM output pin will be reset
to its initial condition, as specified by the T1OC bit, when the T1ON bit changes from
low to high.
Bit 2~0T1RP2~T1RP0: TM1 CCRP 3-bit register, compared with the TM1 Counter
bit 9~bit 7 Comparator P Match Period
000: 1024 TM1clocks
001: 128 TM1 clocks
010: 256 TM1 clocks
011: 384 TM1 clocks
100: 512 TM1 clocks
101: 640 TM1 clocks
110: 768 TM1 clocks
111: 896 TM1 clocks
These three bits are used to setup the value on the internal CCRP 3-bit register, which
are then compared with the internal counter’s highest three bits. The result of this
comparison can be selected to clear the internal counter if the T1CCLR bit is set to
zero. Setting the T1CCLR bit to zero ensures that a compare match with the CCRP
values will reset the internal counter. As the CCRP bits are only compared with the
highest three counter bits, the compare values exist in 128 clock cycle multiples.
Clearing all three bits to zero is in effect allowing the counter to overflow at its
maximum value.
Rev. 1.30
109
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
TM1C1 Register – 10-bit ETM
Bit
7
6
5
4
3
2
1
0
Name
T1AM1
T1AM0
T1AIO1
T1AIO0
T1AOC
T1APOL
T1CDN
T1CCLR
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R
R/W
POR
0
0
0
0
0
0
0
0
Bit 7~6T1AM1~T1AM0: Select TM1 CCRA Operating Mode
00: Compare Match Output Mode
01: Capture Input Mode
10: PWM Mode or Single Pulse Output Mode
11: Timer/Counter Mode
These bits setup the required operating mode for the TM. To ensure reliable operation
the TM should be switched off before any changes are made to the T1AM1 and
T1AM0 bits. In the Timer/Counter Mode, the TM output pin control must be disabled.
Bit 5~4T1AIO1~T1AIO0: Select TP1A 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 TP1A
01: Input capture at falling edge of TP1A
10: Input capture at falling/rising edge of TP1A
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 T1AIO1 and T1AIO0 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 T1AOC bit in the TM1C1 register. Note that the output
level requested by the T1AIO1 and T1AIO0 bits must be different from the initial
value setup using the T1AOC bit otherwise no change will occur on the TM output pin
when a compare match occurs. After the TM output pin changes state it can be reset to
its initial level by changing the level of the T1ON bit from low to high.
In the PWM Mode, the T1AIO1 and T1AIO0 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 T1AIO1 and T1AIO0 bits only after the TM has been switched off. Unpredictable
PWM outputs will occur if the T1AIO1 and T1AIO0 bits are changed when the TM is
running.
Rev. 1.30
110
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
Bit 3T1AOC: TP1A 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 2T1APOL: TP1A Output polarity Control
0: Non-invert
1: Invert
This bit controls the polarity of the TP1A 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 1T1CDN: TM1 Count up or down flag
0: Count up
1: Count down
Bit 0T1CCLR: Select TM1 Counter clear condition
0: TM1 Comparatror P match
1: TM1 Comparatror A match
This bit is used to select the method which clears the counter. Remember that
the Enhanced TM contains three comparators, Comparator A, Comparator B and
Comparator P, but only Comparator A or Comparator P can be selected to clear the
internal counter. With the T1CCLR bit set high, the counter will be cleared when a
compare match occurs from the Comparator A. When the bit is low, the counter will
be cleared when a compare match occurs from the Comparator P or with a counter
overflow. A counter overflow clearing method can only be implemented if the CCRP
bits are all cleared to zero. The T1CCLR bit is not used in the PWM, Single Pulse or
Input Capture Mode.
Rev. 1.30
111
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
TM1C2 Register – 10-bit ETM
Bit
7
6
5
4
3
2
1
0
Name
T1BM1
T1BM0
T1BIO1
T1BIO0
T1BOC
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
T1BPOL T1PWM1 T1PWM0
Bit 7~6T1BM1~T1BM0: Select TM1 CCRB Operating Mode
00: Compare Match Output Mode
01: Capture Input Mode
10: PWM Mode or Single Pulse Output Mode
11: Timer/Counter Mode
These bits setup the required operating mode for the TM. To ensure reliable operation
the TM should be switched off before any changes are made to the T1BM1 and
T1BM0 bits. In the Timer/Counter Mode, the TM output pin control must be disabled.
Bit 5~4T1BIO1~T1BIO0: Select TP1B_0, TP1B_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 TP1B_0, TP1B_1
01: Input capture at falling edge of TP1B_0, TP1B_1
10: Input capture at falling/rising edge of TP1B_0, TP1B_1
11: input capture disabled
Timer/counter Mode
Unused
These two bits are used to determine how the TM output pin changes state when a
certain condition is reached. The function that these bits select depends upon in which
mode the TM is running.
In the Compare Match Output Mode, the T1BIO1 and T1BIO0 bits determine how
the TM output pin changes state when a compare match occurs from the Comparator
B. 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 B. 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 T1BOC bit in the TM1C2 register. Note that the output
level requested by the T1BIO1 and T1BIO0 bits must be different from the initial
value setup using the T1BOC bit otherwise no change will occur on the TM output pin
when a compare match occurs. After the TM output pin changes state it can be reset to
its initial level by changing the level of the T1ON bit from low to high.
In the PWM Mode, the T1BIO1 and T1BIO0 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 T1BIO1 and T1BIO0 bits only after the TM has been switched off. Unpredictable
PWM outputs will occur if the T1BIO1 and T1BIO0 bits are changed when the TM is
running.
Rev. 1.30
112
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
Bit 3T1BOC: TP1B_0, TP1B_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 2T1BPOL: TP1B_0, TP1B_1 Output polarity Control
0: Non-invert
1: Invert
This bit controls the polarity of the TP1B_0, TP1B_1 output pin. When the bit is set
high the TM output pin will be inverted and not inverted when the bit is zero. It has no
effect if the TM is in the Timer/Counter Mode.
Bit 1~0T1PWM1~T1PWM0: Select PWM Mode
00: Edge aligned
01: Centre aligned, compare match on count up
10: Centre aligned, compare match on count down
11: Centre aligned, compare match on count up or down
TM1DL Register – 10-bit ETM
Bit
7
6
5
4
3
2
1
0
Name
D7
D6
D5
D4
D3
D2
D1
D0
R/W
R
R
R
R
R
R
R
R
POR
0
0
0
0
0
0
0
0
2
1
0
Bit 7~0TM1DL: TM1 Counter Low Byte Register bit 7~bit 0
TM1 10-bit Counter bit 7~bit 0
TM1DH Register – 10-bit ETM
Bit
7
6
5
4
3
Name
—
—
—
—
—
—
D9
D8
R/W
—
—
—
—
—
—
R
R
POR
—
—
—
—
—
—
0
0
Bit 7~2
Unimplemented, read as "0"
Bit 1~0TM1DH: TM1 Counter High Byte Register bit 1~bit 0
TM1 10-bit Counter bit 9~bit 8
TM1AL Register – 10-bit ETM
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 7~0TM1AL: TM1 CCRA Low Byte Register bit 7~bit 0
TM1 10-bit CCRA bit 7~bit 0
Rev. 1.30
113
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
TM1AH Register – 10-bit ETM
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 1~0TM1AH: TM1 CCRA High Byte Register bit 1~bit 0
TM1 10-bit CCRA bit 9~bit 8
TM1BL Register – 10-bit ETM
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 7~0TM1BL: TM1 CCRB Low Byte Register bit 7~bit 0
TM1 10-bit CCRB bit 7~bit 0
TM1BH Register – 10-bit ETM
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 1~0TM1BH: TM1 CCRB High Byte Register bit 1~bit 0
TM1 10-bit CCRB bit 9~bit 8
Enhanced Type TM Operating Modes
The Enhanced 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 T1AM1 and T1AM0 bits in the TM1C1, and the T1BM1 and
T1BM0 bits in the TM1C2 register.
ETM Operation Mode
CCRA
Compare
Match Output
Mode
CCRA
CCRA PWM CCRA Single
CCRA Input
Timer/Counter
Output
Pulse Output
Capture Mode
Mode
Mode
Mode
CCRB Compare Match Output Mode
√
—
—
—
—
CCRB Timer/Counter Mode
—
√
—
—
—
CCRB PWM Output Mode
—
—
√
—
—
CCRB Single Pulse Output Mode
—
—
—
√
—
CCRB Input Capture Mode
—
—
—
—
√
“√”: permitted; “—”: not permitted
Rev. 1.30
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Enhanced Flash Type 8-Bit MCU with EEPROM
Compare Match Output Mode
To select this mode, bits T1AM1, T1AM0 and T1BM1, T1BM0 in the TM1C1/TM1C2 registers
should be all cleared to zero. 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 T1CCLR 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 T1AF and T1PF interrupt
request flags for Comparator A and Comparator P respectively, will both be generated.
If the T1CCLR bit in the TM1C1 register is high then the counter will be cleared when a compare
match occurs from Comparator A. However, here only the T1AF interrupt request flag will be
generated even if the value of the CCRP bits is less than that of the CCRA registers. Therefore when
T1CCLR is high no T1PF interrupt request flag will be generated.
As the name of the mode suggests, after a comparison is made, the TM output pin, will change
state. The TM output pin condition however only changes state when a T1AF or T1BF interrupt
request flag is generated after a compare match occurs from Comparator A or Comparator B. The
T1PF 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 is determined by the
condition of the T1AIO1 and T1AIO0 bits in the TM1C1 register for ETM CCRA, and the T1BIO1
and T1BIO0 bits in the TM1C2 register for ETM CCRB. The TM output pin can be selected using
the T1AIO1, T1AIO0 bits (for the TP1A pin) and T1BIO1, T1BIO0 bits (for the TP1B_0, TP1B_1 pins) to go high, to go low or to toggle from its present condition when a compare match occurs
from Comparator A or a compare match occurs from Comparator B. The initial condition of the TM
output pin, is setup after the T1AOC or T1BOC bit for TP1A or TP1B_0, TP1B_1 output pins. Note
that if the T1AIO1, T1AIO0 and T1BIO1, T1BIO0 bits are zero then no pin change will take place.
Rev. 1.30
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HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
Counter Value
Counter overflow
CCRP=0
0x3FF
TnCCLR = 0; TnA� [1:0] = 00
CCRP > 0
Counter cleared b� CCRP value
CCRP > 0
Counter
Restart
Resume
CCRP
Pause
CCRA
Stop
Time
TnON
TnPAU
TnAPOL
CCRP Int.
Flag TnPF
CCRA Int.
Flag TnAF
TPnA O/P
Pin
Output pin set to
initial Level Low
if TnAOC=0
Output not affected b� TnAF
flag. Remains High until reset
b� TnON bit
Output Toggle with
TnAF flag
Here TnAIO [1:0] = 11
Toggle Output select
Note TnAIO [1:0] = 10
Active High Output select
Output Inverts
when TnAPOL is high
Output Pin
Reset to Initial value
Output controlled b�
other pin-shared function
ETM CCRA Compare Match Output Mode – TnCCLR=0
Note: 1. With TnCCLR=0 the Comparator P match will clear the counter
2. TPnA output pin controlled only by TnAF flag
3. Output pin reset to initial state by TnON bit rising edge
4. n=1
Rev. 1.30
116
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
Counter Value
Counter overflow
CCRP=0
0x3FF
TnCCLR = 0; TnB� [1:0] = 00
CCRP > 0
Counter cleared b� CCRP value
CCRP > 0
Counter
Restart
Resume
CCRP
Pause
CCRB
Stop
Time
TnON
TnPAU
TnBPOL
CCRP Int.
Flag TnPF
CCRB Int.
Flag TnBF
TPnB O/P
Pin
Output pin set to
initial Level Low
if TnBOC=0
Output not affected b� TnBF
flag. Remains High until reset
b� TnON bit
Output Toggle with
TnBF flag
Here TnBIO [1:0] = 11
Toggle Output select
Note TnBIO [1:0] = 10
Active High Output select
Output Inverts
when TnBPOL is high
Output Pin
Reset to Initial value
Output controlled b�
other pin-shared function
ETM CCRB Compare Match Output Mode – TnCCLR=0
Note: 1. With TnCCLR=0 the Comparator P match will clear the counter
2. TPnB output pin controlled only by TnBF flag
3. Output pin reset to initial state by TnON bit rising edge
4. n=1
Rev. 1.30
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May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
Counter Value
TnCCLR = 1; TnA� [1:0] = 00
CCRA = 0
Counter overflow
CCRA > 0 Counter cleared b� CCRA value
0x3FF
CCRA=0
Resume
CCRA
Pause
Stop
Counter Restart
CCRP
Time
TnON
TnPAU
TnAPOL
No TnAF flag
generated on
CCRA overflow
CCRA Int.
Flag TnAF
CCRP Int.
Flag TnPF
TnPF not
generated
Output does
not change
TPnA O/P
Pin
Output pin set to
initial Level Low
if TnAOC=0
Output not affected b�
TnAF flag. Remains High
until reset b� TnON bit
Output Toggle with
TnAF flag
Here TnAIO [1:0] = 11
Toggle Output select
Note TnAIO [1:0] = 10
Active High Output select
Output Inverts
when TnAPOL is high
Output Pin
Reset to Initial value
Output controlled b�
other pin-shared function
ETM CCRA Compare Match Output Mode – TnCCLR=1
Note: 1. With TnCCLR=1 the Comparator A match will clear the counter
2. TPnA output pin controlled only by TnAF flag
3. TPnA output pin reset to initial state by TnON rising edge
4. TnPF flags not generated when TnCCLR=1
5. n=1
Rev. 1.30
118
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
Counter Value
0x3FF
TnCCLR = 1; TnB� [1:0] = 00
CCRA = 0
Counter overflow
CCRA > 0 Counter cleared b� CCRA value
Resume
CCRA
Pause
CCRA=0
Stop
Counter Restart
CCRB
Time
TnON
TnPAU
TnBPOL
No TnAF flag
generated on
CCRA overflow
CCRA Int.
Flag TnAF
CCRB Int.
Flag TnBF
TPnB O/P
Pin
Output pin set to
initial Level Low
if TnBOC=0
Output Toggle with
TnBF flag
Here TnBIO [1:0] = 11
Toggle Output select
Output not affected b�
TnBF flag. Remains High
until reset b� TnON bit
Note TnBIO [1:0] = 10
Active High Output select
Output Inverts
when TnBPOL is high
Output Pin
Reset to Initial value
Output controlled b�
other pin-shared function
ETM CCRB Compare Match Output Mode – TnCCLR=1
Note: 1. With TnCCLR=1 the Comparator A match will clear the counter
2. TPnB output pin controlled only by TnBF flag
3. TPnB output pin reset to initial state by TnON rising edge
4. TnPF flags not generated when TnCCLR=1
5. n=1
Rev. 1.30
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May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
Timer/Counter Mode
To select this mode, bits T1AM1, T1AM0 and T1BM1, T1BM0 in the TM1C1 and TM1C2 register
should all be set high. 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, the required bit pairs, T1AM1, T1AM0 and T1BM1, T1BM0 should be set
to 10 respectively and also the T1AIO1, T1AIO0 and T1BIO1, T1BIO0 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 T1CCLR bit is used to determine in which
way the PWM period is controlled. With the T1CCLR bit set high, the PWM period can be finely
controlled using the CCRA registers. In this case the CCRB registers are used to set the PWM duty
value (for TP1B_0 and TP1B_1 output pins). The CCRP bits are not used and TP1A output pin is
not used. The PWM output can only be generated on the TP1B_0 and TP1B_1 output pins. With the
T1CCLR bit cleared to zero, the PWM period is set using one of the eight values of the three CCRP
bits, in multiples of 128. Now both CCRA and CCRB registers can be used to setup different duty
cycle values to provide dual PWM outputs on their relative TP1A and TP1B_0/TP1B_1 pins.
The T1PWM1 and T1PWM0 bits determine the PWM alignment type, which can be either edge
or centre type. In edge alignment, the leading edge of the PWM signals will all be generated
concurrently when the counter is reset to zero. With all power currents switching on at the same
time, this may give rise to problems in higher power applications. In centre alignment the centre
of the PWM active signals will occur sequentially, thus reducing the level of simultaneous power
switching currents.
Interrupt flags, one for each of the CCRA, CCRB and CCRP, will be generated when a compare
match occurs from either the Comparator A, Comparator B or Comparator P. The T1AOC and
T1BOC bits in the TM1C1 and TM1C2 register are used to select the required polarity of the PWM
waveform while the two T1AIO1, T1AIO0 and T1BIO1, T1BIO0 bits pairs are used to enable the
PWM output or to force the TM output pin to a fixed high or low level. The T1APOL and T1BPOL
bit are used to reverse the polarity of the PWM output waveform.
Rev. 1.30
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May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
ETM, PWM Mode, Edge – aligned Mode, T1CCLR=0
CCRP
001b
010b
011b
100b
101b
110b
111b
000b
Period
128
256
384
512
640
768
896
1024
A Duty
CCRA
B Duty
CCRB
If fSYS=16MHz, TM clock source is fSYS/4, CCRP=100b and CCRA=128 and CCRB=256,
The TP1A PWM output frequency=(fSYS/4)/512=fSYS/2048=7.8125kHz, duty=128/512=25%.
The TP1B_n PWM output frequency=(fSYS/4)/512=fSYS/2048=7.8125kHz, duty=256/512=50%.
If the Duty value defined by the CCRA or CCRB register is equal to or greater than the Period value,
then the PWM output duty is 100%.
ETM, PWM Mode, Edge – aligned Mode, T1CCLR=1
CCRA
1
2
3
511
512
1021
1022
1023
Period
1
2
3
511
512
1021
1022
1023
B Duty
CCRB
ETM, PWM Mode, Center – aligned Mode, T1CCLR=0
CCRP
001b
010b
011b
100b
101b
110b
111b
000b
Period
256
512
768
1024
1280
1536
1792
2046
A Duty
(CCRA×2) - 1
B Duty
(CCRB×2) - 1
ETM, PWM Mode, Center – aligned Mode, T1CCLR=1
CCRA
1
2
3
511
512
1021
1022
1023
Period
2
4
6
1022
1024
2042
2044
2046
B Duty
Rev. 1.30
(CCRB×2) - 1
121
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
Counter Value
TnCCLR = 0;
TnA� [1:0] = 10� TnB� [1:0] = 10;
TnPW� [1:0] = 00
Counter Cleared b� CCRP
CCRP
CCRA
Pause
Resume
Stop
CCRB
Counter
Restart
Time
TnON
TnPAU
TnAPOL
CCRA Int.
Flag TnAF
CCRB Int.
Flag TnBF
CCRP Int.
Flag TnPF
TPnA Pin
(TnAOC=1)
TPnB Pin
Dut� C�cle
set b� CCRA
Dut� C�cle
set b� CCRA
Dut� C�cle
set b� CCRA
Output Inverts
when TnAPOL
is high
(TnBOC=1)
TPnB Pin
(TnBOC=0)
Dut� C�cle
set b� CCRB
Output controlled b�
other pin-shared function
Output Pin
Reset to Initial value
PW� Period set b� CCRP
ETM PWM Mode – Edge Aligned
Note: 1. Here TnCCLR=0 therefore CCRP clears counter and determines PWM period
2. Internal PWM function continues even when TnAIO [1:0] (or TnBIO [1:0])=00 or 01
3. CCRA controls TPnA PWM duty and CCRB controls TPnB PWM duty
4. n=1
Rev. 1.30
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May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
Counter Value
Counter Cleared b� CCRA
TnCCLR = 1; TnB� [1:0] = 10;
TnPW� [1:0] = 00
CCRA
Pause
Resume
Counter
Restart
Stop
CCRB
Time
TnON
TnPAU
TnBPOL
CCRP Int.
Flag TnPF
CCRB Int.
Flag TnBF
TPnB Pin
(TnBOC=1)
TPnB Pin
(TnBOC=0)
Dut� C�cle
set b� CCRB
Output controlled b�
other pin-shared function
PW� Period set b� CCRA
Output Pin
Reset to
Initial value
Output Inverts
when TnBPOL
is high
ETM PWM Mode – Edge Aligned
Note: 1. Here TnCCLR=1 therefore CCRA clears counter and determines PWM period
2. Internal PWM function continues even when TnBIO [1:0]=00 or 01
3. CCRA controls TPnB PWM period and CCRB controls TPnB PWM duty
4. Here the TM pin control register should not enable the TPnA pin as a TM output pin
5. n=1
Rev. 1.30
123
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
Counter Value
TnCCLR = 0;
TnA� [1:0] = 10� TnB� [1:0] = 10;
TnPW� [1:0] = 11
CCRP
Resume
CCRA
Stop
Counter
Restart
Pause
CCRB
Time
TnON
TnPAU
TnAPOL
CCRA Int.
Flag TnAF
CCRB Int.
Flag TnBF
CCRP Int.
Flag TnPF
TPnA Pin
(TnAOC=1)
TPnB Pin
Dut� C�cle set b� CCRA
Output Inverts
when TnAPOL
is high
(TnBOC=1)
TPnB Pin
(TnBOC=0)
Dut� C�cle set b� CCRB
Output controlled b�
Other pin-shared function
PW� Period set b� CCRP
Output Pin
Reset to Initial value
ETM PWM Mode – Centre Aligned
Note: 1. Here TnCCLR=0 therefore CCRP clears counter and determines PWM period
2. TnPWM1/TnPWM0=11 therefore PWM is centre aligned
3. Internal PWM function continues even when TnAIO [1:0] (or TnBIO [1:0])=00 or 01
4. CCRA controls TPnA PWM duty and CCRB controls TPnB PWM duty
5. CCRP will generate an interrupt request when the counter decrements to its zero value
6. n=1
Rev. 1.30
124
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
Counter Value
TnCCLR = 1; TnB� [1:0] = 10;
TnPW� [1:0] = 11
CCRA
Resume
Stop
Counter
Restart
Pause
CCRB
Time
TnON
TnPAU
TnBPOL
CCRA Int.
Flag TnAF
CCRB Int.
Flag TnBF
CCRP Int.
Flag TnPF
TPnB Pin
(TnBOC=1)
TPnB Pin
(TnBOC=0)
Output controlled
Output Inverts
b� other pin-shared
when TnBPOL is high
function
Output Pin
Reset to Initial value
Dut� C�cle set b� CCRB
PW� Period set b� CCRA
ETM PWM Mode – Centre Aligned
Note: 1. Here TnCCLR=1 therefore CCRA clears counter and determines PWM period
2. TnPWM1/TnPWM0=11 therefore PWM is centre aligned
3. Internal PWM function continues even when TnBIO [1:0]=00 or 01
4. CCRA controls the TPnB PWM period and CCRB controls the TPnB PWM duty
5. CCRP will generate an interrupt request when the counter decrements to its zero value
6. n=1
Rev. 1.30
125
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
Single Pulse Output Mode
To select this mode, the required bit pairs, T1AM1, T1AM0 and T1BM1, T1BM0 should be set to
10 respectively and also the corresponding T1AIO1, T1AIO0 and T1BIO1, T1BIO0 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 TP1A output leading edge is a low to high transition of the T1ON bit, which
can be implemented using the application program. The trigger for the pulse TP1B output leading
edge is a compare match from Comparator B, which can be implemented using the application
program. However in the Single Pulse Mode, the T1ON bit can also be made to automatically
change from low to high using the external TCK1 pin, which will in turn initiate the Single Pulse
output of TP1A. When the T1ON bit transitions to a high level, the counter will start running and
the pulse leading edge of TP1A will be generated. The T1ON bit should remain high when the pulse
is in its active state. The generated pulse trailing edge of TP1A and TP1B will be generated when
the T1ON 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 T1ON bit and thus
generate the Single Pulse output trailing edge of TP1A and TP1B. In this way the CCRA value can
be used to control the pulse width of TP1A. The CCRA-CCRB value can be used to control the
pulse width of TP1B. A compare match from Comparator A and Comparator B will also generate
TM interrupts. The counter can only be reset back to zero when the T1ON bit changes from low to
high when the counter restarts. In the Single Pulse Mode CCRP is not used. The T1CCLR bit is also
not used.
Counter Value
CCRA
CCRB
0
S/W Command
SET“TnON”
or
TCKn Pin
Transition
Time
CCRA
Leading Edge
CCRA
Trailing Edge
TnON bit
0→1
TnON bit
1→0
S/W Command
CLR“TnON”
or
CCRA Compare
Match
TPnA Output Pin
Pulse Width = CCRA Value
TPnB Output Pin
Pulse Width = (CCRA-CCRB) Value
CCRB Compare
Match
TnON = 1
TnON bit
1→0
CCRB
Leading Edge
CCRB
Trailing Edge
S/W Command
CLR“TnON”
or
CCRA Compare
Match
Single Pulse Generation (n=1)
Rev. 1.30
126
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
Counter Value
TnA� [1:0] = 10� TnB� [1:0] = 10;
TnAIO [1:0] = 11� TnBIO [1:0] = 11
Counter stopped
b� CCRA
CCRA
Pause
Counter Stops
b� software
Resume
CCRB
Counter Reset
when TnON
returns high
Time
TnON
Software
Trigger
Cleared b�
CCRA match
Auto. set b�
TCKn pin
TCKn pin
Software
Trigger
Software
Trigger
Software
Clear
Software
Trigger
TCKn pin
Trigger
TnPAU
TnAPOL
TnBPOL
CCRB Int.
Flag TnBF
CCRA Int.
Flag TnAF
TPnA Pin
(TnAOC=1)
TPnA Pin
Pulse Width
set b� CCRA
(TnAOC=0)
Output Inverts
when TnAPOL=1
TPnB Pin
(TnBOC=1)
TPnB Pin
(TnBOC=0)
Pulse Width set
b� (CCRA-CCRB)
Output Inverts
when TnBPOL=1
ETM – Single Pulse Mode
Note: 1. Counter stopped by CCRA
2. CCRP is not used
3. The pulse 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, TnAIO [1:0] and TnBIO [1:0] must be set to “11” and can not be changed.
6. n=1
Rev. 1.30
127
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
Capture Input Mode
To select this mode bits T1AM1, T1AM0 and T1BM1, T1BM0 in the TM1C1 and TM1C2 registers
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 TP1A and TP1B_0, TP1B_1 pins, whose
active edge can be either a rising edge, a falling edge or both rising and falling edges; the active
edge transition type is selected using the T1AIO1, T1AIO0 and T1BIO1, T1BIO0 bits in the TM1C1
and TM1C2 registers. The counter is started when the T1ON bit changes from low to high which is
initiated using the application program.
When the required edge transition appears on the TP1A and TP1B_0, TP1B_1 pins the present value
in the counter will be latched into the CCRA and CCRB registers and a TM interrupt generated.
Irrespective of what events occur on the TP1A and TP1B_0, TP1B_1 pins the counter will continue
to free run until the T1ON 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 T1AIO1, T1AIO0 and T1BIO1, T1BIO0 bits can select
the active trigger edge on the TP1A and TP1B_0, TP1B_1 pins to be a rising edge, falling edge
or both edge types. If the T1AIO1, T1AIO0 and T1BIO1, T1BIO0 bits are both set high, then no
capture operation will take place irrespective of what happens on the TP1A and TP1B_0, TP1B_1
pins, however it must be noted that the counter will continue to run.
As the TP1A and TP1B_0, TP1B_1 pins are pin shared with other functions, care must be taken
if the TM 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 T1CCLR, T1AOC,
T1BOC, T1APOL and T1BPOL bits are not used in this mode.
Rev. 1.30
128
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
Counter Value
TnA� [1:0] = 01
Counter cleared
b� CCRP
Counter Counter
Reset
Stop
CCRP
YY
Pause
Resume
XX
Time
TnON
TnPAU
T� capture
pin TPnA
Active
edge
Active
edge
Active edge
CCRA Int.
Flag TnAF
CCRP Int.
Flag TnPF
CCRA
Value
TnAIO [1:0]
Value
XX
00 – Rising edge
YY
01 – Falling edge
XX
10 – Both edges
YY
11 – Disable Capture
ETM CCRA Capture Input Mode
Note: 1. T1AM [1:0] = 01 and active edge set by the T1AIO [1:0] bits
2. TM Capture input pin active edge transfers counter value to CCRA
3. TnCCLR bit not used
4. No output function – TnAOC and TnAPOL bits not used
5. CCRP determines the counter value and the counter has a maximum count value when CCRP is equal to
zero.
6. n=1
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TnB�1� TnB�0 = 01
Counter
Value
Counter
overflow
CCRP
Stop
Counter
Reset
YY
XX
Pause
Resume
Time
TnON bit
TnPAU bit
T� Capture Pin
Active
edge
Active
edge
Active
edges
CCRB Int.
Flag TnBF
CCRP Int.
Flag TnPF
CCRB
Value
TnBIO1� TnBIO0
Value
XX
00 - Rising edge
YY
01 - Falling edge
XX
YY
10 - Both edges
11 - Disable Capture
ETM CCRB Capture Input Mode
Note: 1. TnBM [1:0]=01 and active edge set by the TnBIO [1:0] bits
2. The TM Capture input pin active edge transfers the counter value to CCRB
3. The TnCCLR bit is not used
4. No output function – TnBOC and TnBPOL bits are not used
5. CCRP determines the counter value and the counter has a maximum count value when CCRP is equal to
zero.
6. n=1
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Analog to Digital Converter
The need to interface to real world analog signals is a common requirement for many electronic
systems. However, to properly process these signals by a microcontroller, they must first be
converted into digital signals by A/D converters. By integrating the A/D conversion electronic
circuitry into the microcontroller, the need for external components is reduced significantly with the
corresponding follow-on benefits of lower costs and reduced component space requirements. The A/D Converter is only contained in the HT66F30-1 and HT66F20-1 devices.
A/D Overview
The HT66F30-1 contains a multi-channel analog to digital converter which can directly interface to
external analog signals, such as that from sensors or other control signals and convert these signals
directly into either a 12-bit digital value.
Part No.
Input Channels
A/D Channel Select Bits
Input Pins
HT66F30-1/HT66F20-1
8
ACS4, ACS2~ACS0
AN0~AN7
The accompanying block diagram shows the overall internal structure of the A/D converter, together
with its associated registers.
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A/D Converter Structure
A/D Converter Register Description
Overall operation of the A/D converter is controlled using five registers. A read only register pair
exists to store the ADC data 12-bit value. The remaining three registers are control registers which
setup the operating and control function of the A/D converter.
Register Name
ADRL(ADRFS=0)
Bit
7
6
5
4
3
2
1
0
D3
D2
D1
D0
—
—
—
—
ADRL(ADRFS=1)
D7
D6
D5
D4
D3
D2
D1
D0
ADRH(ADRFS=0)
D11
D10
D9
D8
D7
D6
D5
D4
ADRH(ADRFS=1)
—
—
—
—
D11
D10
D9
D8
ADCR0
START
EOCB
ADOFF
ADRFS
—
ACS2
ACS1
ACS0
ADCR1
ACS4
V125EN
—
VREFS
—
ADCK2
ADCK1
ADCK0
ACERL
ACE7
ACE6
ACE5
ACE4
ACE3
ACE2
ACE1
ACE0
A/D Converter Register List – HT66F30-1/HT66F20-1
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A/D Converter Data Registers – ADRL, ADRH
As the HT66F30-1 or HT66F20-1 device contains an internal 12-bit A/D converter, it requires two
data registers to store the converted value. These are a high byte register, known as ADRH, and a
low byte register, known as ADRL. After the conversion process takes place, these registers can be
directly read by the microcontroller to obtain the digitised conversion value. As only 12 bits of the
16-bit register space is utilised, the format in which the data is stored is controlled by the ADRFS bit
in the ADCR0 register as shown in the accompanying table. D0~D11 are the A/D conversion result
data bits. Any unused bits will be read as zero.
ADRFS
0
1
ADRH
7
6
D11 D10
0
0
ADRL
5
4
3
2
1
0
7
6
5
4
3
2
1
0
D9
D8
D7
D6
D5
D4
D3
D2
D1
D0
0
0
0
0
0
0
D11 D10
D9
D8
D7
D6
D5
D4
D3
D2
D1
D0
A/D Data Registers
A/D Converter Control Registers – ADCR0, ADCR1, ACERL
To control the function and operation of the A/D converter, three control registers known as ADCR0,
ADCR1 and ACERL are provided. These 8-bit registers define functions such as the selection of
which analog channel is connected to the internal A/D converter, the digitised data format, the
A/D clock source as well as controlling the start function and monitoring the A/D converter end of
conversion status. The ACS2~ACS0 bits in the ADCR0 register and ACS4 bit is the ADCR1 register
define the ADC input channel number. As the devices contain only one actual analog to digital
converter hardware circuit, each of the individual 8 analog inputs must be routed to the converter. It
is the function of the ACS4 and ACS2~ACS0 bits to determine which analog channel input pins or
internal 1.25V is actually connected to the internal A/D converter.
The ACERL control register contains the ACE7~ACE0 bits which determine which pins on Port A
is used as analog inputs for the A/D converter input and which pins are not to be used as the A/D
converter input. Setting the corresponding bit high will select the A/D input function, clearing the
bit to zero will select either the I/O or other pin-shared function. When the pin is selected to be an
A/D input, its original function whether it is an I/O or other pin-shared function will be removed. In
addition, any internal pull-high resistors connected to these pins will be automatically removed if the
pin is selected to be an A/D input.
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ADCR0 Register
Bit
7
6
5
4
3
2
1
0
Name
START
EOCB
ADOFF
ADRFS
—
ACS2
ACS1
ACS0
R/W
R/W
R
R/W
R/W
—
R/W
R/W
R/W
POR
0
1
1
0
—
0
0
0
Bit 7START: Start the A/D conversion
0→1→0: Start
0→1: Reset the A/D converter and set EOCB to “1”
This bit is used to initiate an A/D conversion process. The bit is normally low but if set
high and then cleared low again, the A/D converter will initiate a conversion process.
When the bit is set high the A/D converter will be reset.
Bit 6EOCB: End of A/D conversion flag
0: A/D conversion ended
1: A/D conversion in progress
This read only flag is used to indicate when an A/D conversion process has completed.
When the conversion process is running, the bit will be high.
Bit 5ADOFF : ADC module power on/off control bit
0: ADC module power on
1: ADC module power off
This bit controls the power to the A/D internal function. This bit should be cleared
to zero to enable the A/D converter. If the bit is set high then the A/D converter will
be switched off reducing the device power consumption. As the A/D converter will
consume a limited amount of power, even when not executing a conversion, this may
be an important consideration in power sensitive battery powered applications.
Note: 1. it is recommended to set ADOFF=1 before entering IDLE/SLEEP Mode for
saving power.
2. ADOFF=1 will power down the ADC module.
Bit 4ADRFS: ADC Data Format Control
0: ADC Data MSB is ADRH bit 7, LSB is ADRL bit 4
1: ADC Data MSB is ADRH bit 3, LSB is ADRL bit 0
This bit controls the format of the 12-bit converted A/D value in the two A/D data
registers. Details are provided in the A/D data register section.
Bit 3
Unimplemented, read as "0"
Bit 2~0ACS2, ACS1, ACS0: Select A/D channel (when ACS4 is “0”)
000: AN0
001: AN1
010: AN2
011: AN3
100: AN4
101: AN5
110: AN6
111: AN7
These are the A/D channel select control bits. As there is only one internal hardware
A/D converter each of the eight A/D inputs must be routed to the internal converter
using these bits. If bit ACS4 in the ADCR1 register is set high then the internal 1.25V
will be routed to the A/D Converter.
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ADCR1 Register
Bit
7
6
5
4
Name
ACS4
R/W
R/W
POR
0
3
2
1
0
V125EN
—
R/W
—
VREFS
—
ADCK2
ADCK1
ADCK0
R/W
—
R/W
R/W
0
—
R/W
0
—
0
0
0
Bit 7ACS4: Select Internal 1.25V bandgap voltage as ADC input
0: Disable
1: Enable
This bit enables the1.25V bandgap voltage to be connected to the A/D converter. The
V125EN bit must first have been set to enable the bandgap circuit 1.25V voltage to be
used by the A/D converter. When the ACS4 bit is set high, the bandgap 1.25V voltage
will be routed to the A/D converter and the other A/D input channels disconnected.
Bit 6V125EN: Internal 1.25V Control
0: Disable
1: Enable
This bit controls the internal Bandgap circuit on/off function to the A/D converter.
When the bit is set high the bandgap voltage 1.25V can be used as an A/D converter
input. If the bandgap voltage 1.25V is not used by the A/D converter and the LVR/LVD
function is disabled then the bandgap reference circuit will be automatically switched
off to conserve power. When 1.25V is switched on for use by the A/D converter, a time
tBG should be allowed for the bandgap circuit to stabilise before implementing an A/D
conversion.
Bit 5
Unimplemented, read as "0"
Bit 4VREFS: Select ADC reference voltage
0: Internal ADC power
1: VREF pin
This bit is used to select the reference voltage for the A/D converter. If the bit is high,
then the A/D converter reference voltage is supplied on the external VREF pin. If the
pin is low, then the internal reference is used which is taken from the power supply pin
VDD.
Bit 3
Unimplemented, read as "0"
Bit 2~0ADCK2, ADCK1, ADCK0: Select ADC clock source
000: fSYS
001: fSYS/2
010: fSYS/4
011: fSYS/8
100: fSYS/16
101: fSYS/32
110: fSYS/64
111: Undefined
These three bits are used to select the clock source for the A/D converter.
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ACERL Register
Bit
7
6
5
4
3
2
1
0
Name
ACE7
ACE6
ACE5
ACE4
ACE3
ACE2
ACE1
ACE0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
1
1
1
1
1
1
1
1
Bit 7ACE7: Define PA7 is A/D input or not
0: Not A/D input
1: A/D input, AN7
Bit 6ACE6: Define PA6 is A/D input or not
0: Not A/D input
1: A/D input, AN6
Bit 5ACE5: Define PA5 is A/D input or not
0: Not A/D input
1: A/D input, AN5
Bit 4ACE4: Define PA4 is A/D input or not
0: Not A/D input
1: A/D input, AN4
Bit 3ACE3: Define PA3 is A/D input or not
0: Not A/D input
1: A/D input, AN3
Bit 2ACE2: Define PA2 is A/D input or not
0: Not A/D input
1: A/D input, AN2
Bit 1ACE1: Define PA1 is A/D input or not
0: Not A/D input
1: A/D input, AN1
Bit 0ACE0: Define PA0 is A/D input or not
0: Not A/D input
1: A/D input, AN0
A/D Operation
The START bit in the ADCR0 register is used to start and reset the A/D converter. When the
microcontroller sets this bit from low to high and then low again, an analog to digital conversion
cycle will be initiated. When the START bit is brought from low to high but not low again, the
EOCB bit in the ADCR0 register will be set high and the analog to digital converter will be reset.
It is the START bit that is used to control the overall start operation of the internal analog to digital
converter.
The EOCB bit in the ADCR0 register is used to indicate when the analog to digital conversion
process is complete. This bit will be automatically set to “0” by the microcontroller after a
conversion cycle has ended. In addition, the corresponding A/D interrupt request flag will be set
in the interrupt control register, and if the interrupts are enabled, an appropriate internal interrupt
signal will be generated. This A/D internal interrupt signal will direct the program flow to the
associated A/D internal interrupt address for processing. If the A/D internal interrupt is disabled,
the microcontroller can be used to poll the EOCB bit in the ADCR0 register to check whether it has
been cleared as an alternative method of detecting the end of an A/D conversion cycle.
The clock source for the A/D converter, which originates from the system clock fSYS, can be chosen
to be either fSYS or a subdivided version of fSYS. The division ratio value is determined by the
ADCK2~ADCK0 bits in the ADCR1 register.
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Although the A/D clock source is determined by the system clocky, f SYS , and by bits
ADCK2~ADCK0, there are some limitations on the maximum A/D clock source speed that can
be selected. As the minimum value of permissible A/D clock period, tADCK, is 0.5μs, care must be
taken for system clock frequencies equal to or greater than 4MHz. For example, if the system clock
operates at a frequency of 4MHz, the ADCK2~ADCK0 bits should not be set to “000”. Doing so
will give A/D clock periods that are less than the minimum A/D clock period which may result in
inaccurate A/D conversion values. Refer to the following table for examples, where values marked
with an asterisk * show where, depending upon the device, special care must be taken, as the values
may be less than the specified minimum A/D Clock Period.
A/D Clock Period (tADCK)
fSYS
ADCK2,
ADCK1,
ADCK0
=000
(fSYS)
ADCK2,
ADCK1,
ADCK0
=001
(fSYS/2)
ADCK2,
ADCK1,
ADCK0
=010
(fSYS/4)
ADCK2,
ADCK1,
ADCK0
=011
(fSYS/8)
ADCK2,
ADCK1,
ADCK0
=100
(fSYS/16)
ADCK2,
ADCK1,
ADCK0
=101
(fSYS/32)
ADCK2,
ADCK1,
ADCK0
=110
(fSYS/64)
ADCK2,
ADCK1,
ADCK0
=111
1MHz
1μs
2μs
4μs
8μs
16μs
32μs
64μs
Undefined
2MHz
500ns
1μs
2μs
4μs
8μs
16μs
32μs
Undefined
4MHz
250ns*
500ns
1μs
2μs
4μs
8μs
16μs
Undefined
8MHz
125ns*
250ns*
500ns
1μs
2μs
4μs
8μs
Undefined
12MHz
83ns*
167ns*
333ns*
667ns
1.33μs
2.67μs
5.33μs
Undefined
A/D Clock Period Examples
Controlling the power on/off function of the A/D converter circuitry is implemented using the
ADOFF bit in the ADCR0 register. This bit must be zero to power on the A/D converter. Even if no
pins are selected for use as A/D inputs by clearing the ACE7~ACE0 bits in the ACERL registers, if
the ADOFF bit is zero then some power will still be consumed. In power conscious applications it
is therefore recommended that the ADOFF is set high to reduce power consumption when the A/D
converter function is not being used.
The reference voltage supply to the A/D Converter can be supplied from either the positive power supply
pin, VDD, or from an external reference sources supplied on pin VREF. The desired selection is made
using the VREFS bit. As the VREF pin is pin-shared with other functions, when the VREFS bit is set
high, the VREF pin function will be selected and the other pin functions will be disabled automatically.
A/D Input Pins
All of the A/D analog input pins are pin-shared with the I/O pins on Port A as well as other
functions. The ACE7~ACE0 bits in the ACERL register, determine whether the input pins are setup
as A/D converter analog inputs or whether they have other functions. If the ACE7~ACE0 bits for its
corresponding pin is set high then the pin will be setup to be an A/D converter input and the original
pin functions disabled. In this way, pins can be changed under program control to change their
function between A/D inputs and other functions. All pull-high resistors, which are setup through
register programming, will be automatically disconnected if the pins are setup as A/D inputs. Note
that it is not necessary to first setup the A/D pin as an input in the PAC port control registers to
enable the A/D input as when the ACE7~ACE0 bits enable an A/D input, the status of the port
control register will be overridden.
The A/D converter has its own reference voltage pin, VREF, however the reference voltage can
also be supplied from the power supply pin, a choice which is made through the VREFS bit in the
ADCR1 register. The analog input values must not be allowed to exceed the value of VREF.
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 ­     
   A/D Input Structure
Summary of A/D Conversion Steps
The following summarises the individual steps that should be executed in order to implement an
A/D conversion process.
• Step 1
Select the required A/D conversion clock by correctly programming bits ADCK2~ADCK0 in the
ADCR1 register.
• Step 2
Enable the A/D by clearing the ADOFF bit in the ADCR0 register to zero.
• Step 3
Select which channel is to be connected to the internal A/D converter by correctly programming
the ACS4, ACS2~ACS0 bits which are also contained in the ADCR1 and ADCR0 register.
• Step 4
Select which pins are to be used as A/D inputs and configure them by correctly programming the
ACE7~ACE0 bits in the ACERL register.
• Step 5
If the interrupts are to be used, the interrupt control registers must be correctly configured to
ensure the A/D converter interrupt function is active. The master interrupt control bit, EMI, and
the A/D converter interrupt bit, ADE, must both be set high to do this.
• Step 6
The analog to digital conversion process can now be initialised by setting the START bit in
the ADCR0 register from low to high and then low again. Note that this bit should have been
originally cleared to zero.
• Step 7
To check when the analog to digital conversion process is complete, the EOCB bit in the ADCR0
register can be polled. The conversion process is complete when this bit goes low. When this
occurs the A/D data register ADRL and ADRH can be read to obtain the conversion value. As an
alternative method, if the interrupts are enabled and the stack is not full, the program can wait for
an A/D interrupt to occur.
Note: When checking for the end of the conversion process, if the method of polling the EOCB
bit in the ADCR0 register is used, the interrupt enable step above can be omitted.
The accompanying diagram shows graphically the various stages involved in an analog to digital
conversion process and its associated timing. After an A/D conversion process has been initiated
by the application program, the microcontroller internal hardware will begin to carry out the
conversion, during which time the program can continue with other functions. The time taken for the
A/D conversion is 16tADCK where tADCK is equal to the A/D clock period.
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‚ ‚
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                  ­      A/D Conversion Timing
Programming Considerations
During microcontroller operations where the A/D converter is not being used, the A/D internal
circuitry can be switched off to reduce power consumption, by setting bit ADOFF high in the
ADCR0 register. When this happens, the internal A/D converter circuits will not consume power
irrespective of what analog voltage is applied to their input lines. If the A/D converter input lines are
used as normal I/Os, then care must be taken as if the input voltage is not at a valid logic level, then
this may lead to some increase in power consumption.
A/D Transfer Function
As the HT66F30-1 contains a 12-bit A/D converter, its full-scale converted digitised value is equal
to FFFH. Since the full-scale analog input value is equal to the VDD or VREF voltage, this gives a
single bit analog input value of VDD or VREF divided by 4096.
1 LSB=(VDD or VREF)÷4096
The A/D Converter input voltage value can be calculated using the following equation:
A/D input voltage=A/D output digital value × (VDD or VREF)÷4096
The diagram shows the ideal transfer function between the analog input value and the digitised
output value for the A/D converter. Except for the digitised zero value, the subsequent digitised
values will change at a point 0.5 LSB below where they would change without the offset, and the
last full scale digitised value will change at a point 1.5 LSB below the VDD or VREF level.
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    
 
      Ideal A/D Transfer Function
A/D Programming Example
The following two programming examples illustrate how to setup and implement an A/D conversion.
In the first example, the method of polling the EOCB bit in the ADCR0 register is used to detect
when the conversion cycle is complete, whereas in the second example, the A/D interrupt is used to
determine when the conversion is complete.
Example: using an EOCB polling method to detect the end of conversion
clr
ADE;
mova,03H
mov ADCR1,a ;
clr ADOFF
mov a,0Fh ;
mov ACERL,a
mova,00h
mov ADCR0,a ;
:
start_conversion:
clr START ;
set START ;
clr START ;
polling_EOC:
sz EOCB ;
;
jmp polling_EOC ;
mov a,ADRL ;
mov ADRL_buffer,a ;
mov a,ADRH ;
mov ADRH_buffer,a ;
:
:
jmp start_conversion ;
Rev. 1.30
disable ADC interrupt
select fSYS/8 as A/D clock and switch off 1.25V
setup ACERL to configure pins AN0~AN3
enable and connect AN0 channel to A/D converter
high pulse on start bit to initiate conversion
reset A/D
start A/D
poll the ADCR0 register EOCB bit to detect end
of A/D conversion
continue polling
read low byte conversion result value
save result to user defined register
read high byte conversion result value
save result to user defined register
start next a/d conversion
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Example: using the interrupt method to detect the end of conversion
clr
ADE; disable ADC interrupt
mova,03H
mov ADCR1,a ; select fSYS/8 as A/D clock and switch off 1.25V
Clr ADOFF
mov a,0Fh ; setup ACERL to configure pins AN0~AN3
mov ACERL,a
mova,00h
mov ADCR0,a ; enable and connect AN0 channel to A/D converter
Start_conversion:
clr START ; high pulse on START bit to initiate conversion
set START ; reset A/D
clr START ; start A/D
clr ADF ; clear ADC interrupt request flag
set ADE; enable ADC interrupt
set EMI ; enable global interrupt
:
:
; ADC interrupt service routine
ADC_ISR:
mov acc_stack,a ; save ACC to user defined memory
mov a,STATUS
mov status_stack,a ; save STATUS to user defined memory
:
:
mov a,ADRL ; read low byte conversion result value
mov adrl_buffer,a ; save result to user defined register
mov a,ADRH ; read high byte conversion result value
mov adrh_buffer,a ; save result to user defined register
:
:
EXIT_INT_ISR:
mov a,status_stack
mov STATUS,a ; restore STATUS from user defined memory
mov a,acc_stack ; restore ACC from user defined memory
reti
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Comparators
Two independent analog comparators are contained within these devices. These functions offer
flexibility via their register controlled features such as power-down, polarity select, hysteresis etc.
In sharing their pins with normal I/O pins the comparators do not waste precious I/O pins if there
functions are otherwise unused.
Comparator
Comparator Operation
The devices contain two comparator functions which are used to compare two analog voltages
and provide an output based on their difference. Full control over the two internal comparators
is provided via two control registers, CP0C and CP1C, one assigned to each comparator. The
comparator output is recorded via a bit in their respective control register, but can also be transferred
out onto a shared I/O pin. Additional comparator functions include, output polarity, hysteresis
functions and power down control.
Any pull-high resistors connected to the shared comparator input pins will be automatically
disconnected when the comparator is enabled. As the comparator inputs approach their switching
level, some spurious output signals may be generated on the comparator output due to the slow
rising or falling nature of the input signals. This can be minimised by selecting the hysteresis
function will apply a small amount of positive feedback to the comparator. Ideally the comparator
should switch at the point where the positive and negative inputs signals are at the same voltage
level, however, unavoidable input offsets introduce some uncertainties here. The hysteresis function,
if enabled, also increases the switching offset value.
Comparator Registers
There are two registers for overall comparator operation, one for each comparator. As corresponding
bits in the two registers have identical functions, they following register table applies to both
registers.
Bit
Register
Name
7
6
5
4
3
2
1
0
CP0C
C0SEL
C0EN
C0POL
C0OUT
C0OS
—
—
C0HYEN
CP1C
C1SEL
C1EN
C1POL
C1OUT
C1OS
—
—
C1HYEN
Comparator Registers List
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CP0C Register
Bit
7
6
5
4
3
2
1
0
Name
C0SEL
C0EN
C0POL
C0OUT
C0OS
R/W
R/W
R/W
R/W
R
R/W
—
—
C0HYEN
—
—
POR
1
0
0
0
0
—
R/W
—
1
C0SEL: Select Comparator pins or I/O pins
0: I/O pin select
1: Comparator pin select
This is the Comparator pin or I/O pin select bit. If the bit is high the comparator will
be selected and the two comparator input pins will be enabled. As a result, these two
pins will lose their I/O pin functions. Any pull-high configuration options associated
with the comparator shared pins will also be automatically disconnected.
Bit 6C0EN: Comparator On/Off control
0: Off
1: On
This is the Comparator on/off control bit. If the bit is zero the comparator will be
switched off and no power consumed even if analog voltages are applied to its inputs.
For power sensitive applications this bit should be cleared to zero if the comparator is
not used or before the devices enter the SLEEP or IDLE mode.
Bit 5C0POL: Comparator output polarity
0: output not inverted
1: output inverted
This is the comparator polarity bit. If the bit is zero then the C0OUT bit will reflect
the non-inverted output condition of the comparator. If the bit is high the comparator
C0OUT bit will be inverted.
Bit 4C0OUT: Comparator output bit
C0POL=0
0: C0+ < C01: C0+ > C0C0POL=1
0: C0+ > C01: C0+ < C0This bit stores the comparator output bit. The polarity of the bit is determined by the
voltages on the comparator inputs and by the condition of the C0POL bit.
Bit 3C0OS: Output path select
0: C0X pin
1: Internal use
This is the comparator output path select control bit. If the bit is set to "0" and the
C0SEL bit is "1" the comparator output is connected to an external C0X pin. If the
bit is set to "1" or the C0SEL bit is "0" the comparator output signal is only used
internally by the devices allowing the shared comparator output pin to retain its normal
I/O operation.
Bit 2~1
Unimplemented, read as "0"
Bit 0C0HYEN: Hysteresis Control
0: Off
1: On
This is the hysteresis control bit and if set high will apply a limited amount of
hysteresis to the comparator, as specified in the Comparator Electrical Characteristics
table. The positive feedback induced by hysteresis reduces the effect of spurious
switching near the comparator threshold.
Bit 7
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CP1C Register
Bit
7
6
5
4
3
2
1
0
Name
C1SEL
C1EN
C1POL
C1OUT
C1OS
—
—
C1HYEN
R/W
R/W
R/W
R/W
R
R/W
—
—
R/W
POR
1
0
0
0
0
—
—
1
Bit 7C1SEL: Select Comparator pins or I/O pins
0: I/O pin select
1: Comparator pin select
This is the Comparator pin or I/O pin select bit. If the bit is high the comparator will
be selected and the two comparator input pins will be enabled. As a result, these two
pins will lose their I/O pin functions. Any pull-high configuration options associated
with the comparator shared pins will also be automatically disconnected.
Bit 6C1EN: Comparator On/Off control
0: Off
1: On
This is the Comparator on/off control bit. If the bit is zero the comparator will be
switched off and no power consumed even if analog voltages are applied to its inputs.
For power sensitive applications this bit should be cleared to zero if the comparator is
not used or before the devices enter the SLEEP or IDLE mode.
Bit 5C1POL: Comparator output polarity
0: output not inverted
1: output inverted
This is the comparator polarity bit. If the bit is zero then the C1OUT bit will reflect
the non-inverted output condition of the comparator. If the bit is high the comparator
C1OUT bit will be inverted.
Bit 4C1OUT: Comparator output bit
C1POL=0
0: C1+ < C11: C1+ > C1C1POL=1
0: C1+ > C11: C1+ < C1This bit stores the comparator output bit. The polarity of the bit is determined by the
voltages on the comparator inputs and by the condition of the C1POL bit.
Bit 3C1OS: Output path select
0: C1X pin
1: Internal use
This is the comparator output path select control bit. If the bit is set to "0" and the
C1SEL bit is "1" the comparator output is connected to an external C1X pin. If the
bit is set to "1" or the C1SEL bit is "0" the comparator output signal is only used
internally by the devices allowing the shared comparator output pin to retain its normal
I/O operation.
Bit 2~1
Unimplemented, read as "0"
Bit 0C1HYEN: Hysteresis Control
0: Off
1: On
This is the hysteresis control bit and if set high will apply a limited amount of
hysteresis to the comparator, as specified in the Comparator Electrical Characteristics
table. The positive feedback induced by hysteresis reduces the effect of spurious
switching near the comparator threshold.
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Comparator Interrupt
Each also possesses its own interrupt function. When any one of the changes state, its relevant
interrupt flag will be set, and if the corresponding interrupt enable bit is set, then a jump to its
relevant interrupt vector will be executed. Note that it is the changing state of the C0OUT or C1OUT
bit and not the output pin which generates an interrupt. If the microcontroller is in the SLEEP or
IDLE Mode and the Comparator is enabled, then if the external input lines cause the Comparator
output to change state, the resulting generated interrupt flag will also generate a wake-up. If it is
required to disable a wake-up from occurring, then the interrupt flag should be first set high before
entering the SLEEP or IDLE Mode.
Programming Considerations
If the comparator is enabled, it will remain active when the microcontroller enters the SLEEP or
IDLE Mode, however as it will consume a certain amount of power, the user may wish to consider
disabling it before the SLEEP or IDLE Mode is entered.
As comparator pins are shared with normal I/O pins the I/O registers for these pins will be read as
zero (port control register is "1") or read as port data register value (port control register is "0") if the
comparator function is enabled.
Serial Interface Module – SIM
These devices contain a Serial Interface Module, which includes both the four line SPI interface or
the two line I2C interface types, to allow an easy method of communication with external peripheral
hardware. Having relatively simple communication protocols, these serial interface types allow
the microcontroller to interface to external SPI or I2C based hardware such as sensors, Flash or
EEPROM memory, etc. The SIM interface pins are pin-shared with other I/O pins therefore the SIM
interface function must first be selected using a configuration option. As both interface types share
the same pins and registers, the choice of whether the SPI or I2C type is used is made using the SIM
operating mode control bits, named SIM2~SIM0, in the SIMC0 register. These pull-high resistors of
the SIM pin-shared I/O are selected using pull-high control registers, and also if the SIM function is
enabled.
SPI Interface
The SPI interface is often used to communicate with external peripheral devices such as sensors,
Flash or EEPROM memory devices etc. Originally developed by Motorola, the four line SPI
interface is a synchronous serial data interface that has a relatively simple communication protocol
simplifying the programming requirements when communicating with external hardware devices.
The communication is full duplex and operates as a slave/master type, where the devices can be
either master or slave. Although the SPI interface specification can control multiple slave devices
from a single master, but these devices 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.
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SPI Interface Operation
The SPI interface is a full duplex synchronous serial data link. It is a four line interface with pin
names SDI, SDO, SCK and SCS. Pins SDI and SDO are the Serial Data Input and Serial Data
Output lines, SCK is the Serial Clock line and SCS is the Slave Select line. As the SPI interface
pins are pin-shared with other functions and with the I2C function pins, the SPI interface must first
be selected by the correct bits in the SIMC0 and SIMC2 registers. After the SPI option has been
selected, it can also be additionally disabled or enabled using the SIMEN bit in the SIMC0 register.
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.
SPI Master/Slave Connection
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The SPI function in these devices offers the following features:
• Full duplex synchronous data transfer
• Both Master and Slave modes
• LSB first or MSB first data transmission modes
• Transmission complete flag
• Rising or falling active clock edge
• WCOL bit enabled or disable select
The status of the SPI interface pins is determined by a number of factors such as whether the devices
are in the master or slave mode and upon the condition of certain control bits such as CSEN and
SIMEN.
There are several configuration options associated with the SPI interface. One of these is to
enable the SIM function which selects the SIM pins rather than normal I/O pins. Note that if the
configuration option does not select the SIM function then the SIMEN bit in the SIMC0 register will
have no effect. Another two SPI configuration options determine if the CSEN and WCOL bits are to
be used.
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
4
3
2
1
SIMC0
SIM2
SIM1
SIM0
PCKEN
PCKP1
PCKP0
SIMEN
—
SIMD
D7
D6
D5
D4
D3
D2
D1
D0
SIMC2
D7
D6
CKPOLB
CKEG
MLS
CSEN
WCOL
TRF
0
SIM Registers List
The SIMD register is used to store the data being transmitted and received. The same register is used
by both the SPI and I2C functions. Before the devices write data to the SPI bus, the actual data to
be transmitted must be placed in the SIMD register. After the data is received from the SPI bus, the
devices can read it from the SIMD register. Any transmission or reception of data from the SPI bus
must be made via the SIMD register.
• SIMD Register
Bit
7
6
5
4
3
2
1
0
Name
D7
D6
D5
D4
D3
D2
D1
D0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
x
x
x
x
x
x
x
x
"x" unknown
There are also 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.
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• SIMC0 Register
Bit
7
6
5
4
3
2
1
0
Name
SIM2
SIM1
SIM0
PCKEN
PCKP1
PCKP0
SIMEN
—
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
—
POR
1
1
1
0
0
0
0
—
Bit 7~5
SIM2, SIM1, SIM0: SIM Operating Mode Control
000: SPI master mode; SPI clock is fSYS/4
001: SPI master mode; SPI clock is fSYS/16
010: SPI master mode; SPI clock is fSYS/64
011: SPI master mode; SPI clock is fTBC
100: SPI master mode; SPI clock is TM0 CCRP match frequency/2
101: SPI slave mode
110: I2C slave mode
111: Non SIM function
These bits setup the overall operating mode of the SIM function. As well as selecting
if the I2C or SPI function, they are used to control the SPI Master/Slave selection and
the SPI Master clock frequency. The SPI clock is a function of the system clock but
can also be chosen to be sourced from TM0. If the SPI Slave Mode is selected then the
clock will be supplied by an external Master devices.
Bit 4PCKEN: PCK Output Pin Control
0: Disable
1: Enable
Bit 3~2
PCKP1, PCKP0: Select PCK output pin frequency
00: fSYS
01: fSYS/4
10: fSYS/8
11: TM0 CCRP match frequency/2
Bit 1SIMEN: SIM Control
0: Disable
1: Enable
The bit is the overall on/off control for the SIM interface. When the SIMEN bit is
cleared to zero to disable the SIM interface, the SDI, SDO, SCK and SCS, or SDA and
SCL lines will lose their SPI or I2C function and the SIM operating current will be
reduced to a minimum value. When the bit is high the SIM interface is enabled. 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 0
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• 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 7~6
Undefined bit
This bit can be read or written by the application program.
Bit 5CKPOLB: Determines the base condition of the clock line
0: the SCK line will be high when the clock is inactive
1: the SCK line will be low when the clock is inactive
The CKPOLB bit determines the base condition of the clock line, if the bit is high,
then the SCK line will be low when the clock is inactive. When the CKPOLB bit is
low, then the SCK line will be high when the clock is inactive.
Bit 4CKEG: Determines SPI SCK active clock edge type
CKPOLB=0
0: SCK is high base level and data capture at SCK rising edge
1: SCK is high base level and data capture at SCK falling edge
CKPOLB=1
0: SCK is low base level and data capture at SCK falling edge
1: SCK is low base level and data capture at SCK rising edge
The CKEG and CKPOLB bits are used to setup the way that the clock signal outputs
and inputs data on the SPI bus. These two bits must be configured before data transfer
is executed otherwise an erroneous clock edge may be generated. The CKPOLB bit
determines the base condition of the clock line, if the bit is high, then the SCK line
will be low when the clock is inactive. When the CKPOLB bit is low, then the SCK
line will be high when the clock is inactive. The CKEG bit determines active clock
edge type which depends upon the condition of CKPOLB bit.
Bit 3MLS: SPI Data shift order
0: LSB
1: MSB
This is the data shift select bit and is used to select how the data is transferred, either
MSB or LSB first. Setting the bit high will select MSB first and low for LSB first.
Bit 2CSEN: SPI SCS pin Control
0: Disable
1: Enable
The CSEN bit is used as an enable/disable for the SCS pin. If this bit is low, then the
SCS pin will be disabled and placed into I/O pin or the other functions. If the bit is
high the SCS pin will be enabled and used as a select pin.
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 “1” automatically when
an SPI data transmission is completed, but must set to “0” by the application program.
It can be used to generate an interrupt.
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SPI Communication
After the SPI interface is enabled by setting the SIMEN bit high, then in the Master Mode, when
data is written to the SIMD register, transmission/reception will begin simultaneously. When the
data transfer is complete, the TRF flag will be set automatically, but must be cleared using the
application program. In the Slave Mode, when the clock signal from the master has been received,
any data in the SIMD register will be transmitted and any data on the SDI pin will be shifted into
the SIMD register. The master should output an SCS signal to enable the slave devices before a
clock signal is provided. The slave data to be transferred should be well prepared at the appropriate
moment relative to the SCS signal depending upon the configurations of the CKPOLB bit and CKEG
bit. The accompanying timing diagram shows the relationship between the slave data and SCS signal
for various configurations of the CKPOLB and CKEG bits.
The SPI will continue to function even in the IDLE Mode.
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I2C Interface
The I 2C interface is used to communicate with external peripheral devices such as sensors,
EEPROM memory etc. Originally developed by Philips, it is a two line low speed serial interface
for synchronous serial data transfer. The advantage of only two lines for communication, relatively
simple communication protocol and the ability to accommodate multiple devices on the same bus
has made it an extremely popular interface type for many applications.
I2C Master Slave Bus Connection
I2C Interface Operation
The I2C serial interface is a two line interface, a serial data line, SDA, and serial clock line, SCL. As
many devices may be connected together on the same bus, their outputs are both open drain types.
For this reason it is necessary that external pull-high resistors are connected to these outputs. Note
that no chip select line exists, as each device on the I2C bus is identified by a unique address which
will be transmitted and received on the I2C bus.
When two devices communicate with each other on the bidirectional I2C bus, one is known as the
master device and one as the slave device. Both master and slave can transmit and receive data,
however, it is the master device that has overall control of the bus. For these devices, which only
operate in slave mode, there are two methods of transferring data on the I2C bus, the slave transmit
mode and the slave receive mode.
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There are several configuration options associated with the I2C interface. One of these is to enable
the function which selects the SIM pins rather than normal I/O pins. Note that if the configuration
option does not select the SIM function then the SIMEN bit in the SIMC0 register will have no
effect. A configuration option exists to allow a clock other than the system clock to drive the I2C
interface. Another configuration option determines the debounce time of the I2C interface. This uses
the internal clock to in effect add a debounce time to the external clock to reduce the possibility
of glitches on the clock line causing erroneous operation. The debounce time, if selected, can be
chosen to be either 2 or 4 system clocks. To achieve the required I2C data transfer speed, there
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exists a relationship between the system clock, fSYS, and the I2C debounce time. For either the I2C
Standard or Fast mode operation, users must take care of the selected system clock frequency and
the configured debounce time to match the criterion shown in the following table.
I2C Debounce Time Selection
I2C Standard Mode (100kHz)
I2C Fast Mode (400kHz)
No debounce
fSYS > 2MHz
fSYS > 5MHz
2 system clock debounce
fSYS > 4MHz
fSYS > 10MHz
4 system clock debounce
fSYS > 8MHz
fSYS > 20MHz
I2C Minimum fSYS Frequency
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I2C Registers
There are three control registers associated with the I2C bus, SIMC0, SIMC1 and 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.
Bit
Register
Name
7
6
5
4
3
2
1
0
SIMC0
SIM2
SIM1
SIM0
PCKEN
PCKP1
PCKP0
SIMEN
—
SIMC1
HCF
HANS
HBB
HTX
TXAK
SRW
IAMWU
RXAK
SIMD
D7
D6
D5
D4
D3
D2
D1
D0
SIMA
IICA6
IICA5
IICA4
IICA3
IICA2
IICA1
IICA0
D0
I2C Registers List
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• SIMC0 Register
Bit
7
6
5
4
3
2
1
Name
SIM2
SIM1
SIM0
PCKEN
PCKP1
PCKP0
SIMEN
—
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
—
POR
1
1
1
0
0
0
0
—
Bit 7~5
0
SIM2, SIM1, SIM0: SIM Operating Mode Control
000: SPI master mode; SPI clock is fSYS/4
001: SPI master mode; SPI clock is fSYS/16
010: SPI master mode; SPI clock is fSYS/64
011: SPI master mode; SPI clock is fTBC
100: SPI master mode; SPI clock is TM0 CCRP match frequency/2
101: SPI slave mode
110: I2C slave mode
111: Non SIM function
These bits setup the overall operating mode of the SIM function. As well as selecting
if the I2C or SPI function, they are used to control the SPI Master/Slave selection and
the SPI Master clock frequency. The SPI clock is a function of the system clock but
can also be chosen to be sourced from the TM0. If the SPI Slave Mode is selected then
the clock will be supplied by an external Master device.
Bit 4PCKEN: PCK Output Pin Control
0: Disable
1: Enable
Bit 3~2
PCKP1, PCKP0: Select PCK output pin frequency
00: fSYS
01: fSYS/4
10: fSYS/8
11: TM0 CCRP match frequency/2
Bit 1SIMEN: SIM Control
0: Disable
1: Enable
The bit is the overall on/off control for the SIM interface. When the SIMEN bit is
cleared to zero to disable the SIM interface, the SDI, SDO, SCK and SCS, or SDA
and SCL lines will be in a floating condition and the SIM operating current will be
reduced to a minimum value. When the bit is high the SIM interface is enabled. 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 SIM2~SIM0 bits,
the contents of the SPI control registers will remain at the previous settings when the
SIMEN bit changes from low to high and should therefore be first initialised by the
application program. If the SIM is configured to operate as an I2C interface via the
SIM2~SIM0 bits and the SIMEN bit changes from low to high, the contents of the I2C
control bits such as HTX and TXAK will remain at the previous settings and should
therefore be first initialised by the application program while the relevant I2C flags
such as HCF, HAAS, HBB, SRW and RXAK will be set to their default states.
Bit 0
Rev. 1.30
Unimplemented, read as "0"
153
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
• SIMC1 Register
Bit
7
6
5
4
3
2
1
0
Name
HCF
HAAS
HBB
HTX
TXAK
SRW
IAMWU
RXAK
R/W
R
R
R
R/W
R/W
R
R/W
R
POR
1
0
0
0
0
0
0
1
Bit 7HCF: I2C Bus data transfer completion flag
0: Data is being transferred
1: Completion of an 8-bit data transfer
The HCF flag is the data transfer flag. This flag will be zero when data is being
transferred. Upon completion of an 8-bit data transfer the flag will go high and an
interrupt will be generated.
Bit 6HAAS: I2C Bus address match flag
0: Not address match
1: Address match
The HAAS flag is the address match flag. This flag is used to determine if the slave
device address is the same as the master transmit address. If the addresses match then
this bit will be high, if there is no match then the flag will be low.
Bit 5HBB: I2C Bus busy flag
0: I2C Bus is not busy
1: I2C Bus is busy
The HBB flag is the I2C busy flag. This flag will be “1” when the I2C bus is busy
which will occur when a START signal is detected. The flag will be set to “0” when
the bus is free which will occur when a STOP signal is detected.
Bit 4HTX: Select I2C slave device is transmitter or receiver
0: Slave device is the receiver
1: Slave device is the transmitter
Bit 3TXAK: I2C Bus transmit acknowledge flag
0: Slave send acknowledge flag
1: Slave do not send acknowledge flag
The TXAK bit is the transmit acknowledge flag. After the slave device receipt of 8-bits
of data, this bit will be transmitted to the bus on the 9th clock from the slave device.
The slave device must always set TXAK bit to “0” before further data is received.
Bit 2SRW: I2C Slave Read/Write flag
0: Slave device should be in receive mode
1: Slave device should be in transmit mode
The SRW flag is the I 2C Slave Read/Write flag. This flag determines whether
the master device wishes to transmit or receive data from the I2C bus. When the
transmitted address and slave address is match, that is when the HAAS flag is set high,
the slave device will check the SRW flag to determine whether it should be in transmit
mode or receive mode. If the SRW flag is high, the master is requesting to read data
from the bus, so the slave device should be in transmit mode. When the SRW flag
is zero, the master will write data to the bus, therefore the slave device should be in
receive mode to read this data.
Bit 1IAMWU: I2C Address Match Wake-up Control
0: Disable
1: Enable - must be cleared by the application program after wake-up
This bit should be set to 1 to enable the I2C address match wake up from the SLEEP
or IDLE Mode. If the IAMWU bit has been set before entering either the SLEEP or
IDLE mode to enable the I2C address match wake up, then this bit must be cleared by
the application program after wake-up to ensure correction device operation.
Rev. 1.30
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May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
Bit 0RXAK: I2C Bus Receive acknowledge flag
0: Slave receive acknowledge flag
1: Slave does not receive acknowledge flag
The RXAK flag is the receiver acknowledge flag. When the RXAK flag is “0”, it
means that a acknowledge signal has been received at the 9th clock, after 8 bits of data
have been transmitted. When the slave device in the transmit mode, the slave device
checks the RXAK flag to determine if the master receiver wishes to receive the next
byte. The slave transmitter will therefore continue sending out data until the RXAK
flag is “1”. When this occurs, the slave transmitter will release the SDA line to allow
the master to send a STOP signal to release the I2C Bus.
The SIMD register is used to store the data being transmitted and received. The same register is
used by both the SPI and I2C functions. Before the devices write data to the SPI bus, the actual
data to be transmitted must be placed in the SIMD register. After the data is received from the
SPI bus, the devices can read it from the SIMD register. Any transmission or reception of data
from the SPI bus must be made via the SIMD register.
• SIMD Register
Bit
7
6
5
4
3
2
1
0
Name
D7
D6
D5
D4
D3
D2
D1
D0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
x
X
x
x
x
x
x
x
"x" unknown
• SIMA Register
Bit
7
6
5
4
3
2
1
0
Name
IICA6
IICA5
IICA4
IICA3
IICA2
IICA1
IICA0
—
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
—
POR
x
X
x
x
x
x
x
—
"x" unknown
Bit 7~1IICA6~IICA0: I2C slave address
IICA6~IICA0 is the I2C slave address bit 6~bit 0.
The SIMA register is also used by the SPI interface but has the name SIMC2. The
SIMA register is the location where the 7-bit slave address of the slave device is
stored. Bits 7~1 of the SIMA register define the device slave address. Bit 0 is not
defined.
When a master device, which is connected to the I2C bus, sends out an address, which
matches the slave address in the SIMA register, the slave device will be selected. Note
that the SIMA register is the same register address as SIMC2 which is used by the SPI
interface.
Bit 0
Rev. 1.30
Undefined bit
This bit can be read or written by user software program.
155
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Enhanced Flash Type 8-Bit MCU with EEPROM
I2C Bus Communication
Communication on the I2C bus requires four separate steps, a START signal, a slave device address
transmission, a data transmission and finally a STOP signal. When a START signal is placed on
the I2C bus, all devices on the bus will receive this signal and be notified of the imminent arrival of
data on the bus. The first seven bits of the data will be the slave address with the first bit being the
MSB. If the address of the slave device matches that of the transmitted address, the HAAS bit in the
SIMC1 register will be set and an I2C interrupt will be generated. After entering the interrupt service
routine, the slave device must first check the condition of the HAAS bit to determine whether the
interrupt source originates from an address match or from the completion of an 8-bit data transfer.
During a data transfer, note that after the 7-bit slave address has been transmitted, the following bit,
which is the 8th bit, is the read/write bit whose value will be placed in the SRW bit. This bit will be
checked by the slave device to determine whether to go into transmit or receive mode. Before any
transfer of data to or from the I2C bus, the microcontroller must initialise the bus, the following are
steps to achieve this:
• Step 1
Set the SIM2~SIM0 and SIMEN bits in the SIMC0 register to “1” to enable the I2C bus.
• Step 2
Write the slave address of the device to the I2C bus address register SIMA.
• Step 3
Set the SIME and SIM Muti-Function interrupt enable bit of the interrupt control register to
enable the SIM interrupt and Multi-function interrupt.

 € ‚   ƒ „ … ‚     ­
  ­
I2C Bus Initialisation Flow Chart
Rev. 1.30
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May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
I2C Bus Start Signal
The START signal can only be generated by the master device connected to the I2C bus and not by
the slave device. This START signal will be detected by all devices connected to the I2C bus. When
detected, this indicates that the I2C bus is busy and therefore the HBB bit will be set. A START
condition occurs when a high to low transition on the SDA line takes place when the SCL line
remains high.
Slave Address
The transmission of a START signal by the master will be detected by all devices on the I2C bus.
To determine which slave device the master wishes to communicate with, the address of the slave
device will be sent out immediately following the START signal. All slave devices, after receiving
this 7-bit address data, will compare it with their own 7-bit slave address. If the address sent out by
the master matches the internal address of the microcontroller slave device, then an internal I2C bus
interrupt signal will be generated. The next bit following the address, which is the 8th bit, defines
the read/write status and will be saved to the SRW bit of the SIMC1 register. The slave device will
then transmit an acknowledge bit, which is a low level, as the 9th bit. The slave device will also set
the status flag HAAS when the addresses match.
As an 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 devices must be placed in either the transmit mode and then write data to the SIMD
register, or in the receive mode where it must implement a dummy read from the SIMD register to
release the SCL line.
I2C Bus Read/Write Signal
The SRW bit in the SIMC1 register defines whether the slave device wishes to read data from the
I2C bus or write data to the I2C bus. The slave device should examine this bit to determine if it is to
be a transmitter or a receiver. If the SRW flag is “1” then this indicates that the master device wishes
to read data from the I2C bus, therefore the slave device must be setup to send data to the I2C bus as
a transmitter. If the SRW flag is “0” then this indicates that the master wishes to send data to the I2C
bus, therefore the slave device must be setup to read data from the I2C bus as a receiver.
I2C Bus Slave Address Acknowledge Signal
After the master has transmitted a calling address, any slave device on the I 2C bus, whose
own internal address matches the calling address, must generate an acknowledge signal. The
acknowledge signal will inform the master that a slave device has accepted its calling address. If no
acknowledge signal is received by the master then a STOP signal must be transmitted by the master
to end the communication. When the HAAS flag is high, the addresses have matched and the slave
device must check the SRW flag to determine if it is to be a transmitter or a receiver. If the SRW flag
is high, the slave device should be setup to be a transmitter so the HTX bit in the SIMC1 register
should be set to “1”. If the SRW flag is low, then the microcontroller slave device should be setup as
a receiver and the HTX bit in the SIMC1 register should be set to “0”.
Rev. 1.30
157
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
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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­
         ­ Note: *When a slave address is matched, the devices must be placed in either the transmit mode
and then write data to the SIMD register, or in the receive mode where it must implement a
dummy read from the SIMD register to release the SCL line.
I2C Communication Timing Diagram
Rev. 1.30
158
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
          I2C Bus ISR flow Chart
Rev. 1.30
159
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
Peripheral Clock Output
The Peripheral Clock Output allows the device to supply external hardware with a clock signal
synchronised to the microcontroller clock.
Peripheral Clock Operation
As the peripheral clock output pin, PCK, is shared with I/O line, the required pin function is chosen via
PCKEN in the SIMC0 register. The Peripheral Clock function is controlled using the SIMC0 register.
The clock source for the Peripheral Clock Output can originate from either the TM0 CCRP match
frequency/2 or a divided ratio of the internal fSYS clock. The PCKEN bit in the SIMC0 register is the
overall on/off control, setting PCKEN bit to "1" enables the Peripheral Clock, setting PCKEN bit to "0"
disables it. The required division ratio of the system clock is selected using the PCKP1 and PCKP0 bits
in the same register. If the device enters the SLEEP Mode this will disable the Peripheral Clock output.
SIMC0 Register
Bit
7
6
5
4
3
2
1
0
Name
SIM2
SIM1
SIM0
PCKEN
PCKP1
PCKP0
SIMEN
—
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
—
POR
1
1
1
0
0
0
0
—
Bit 7~5SIM2, SIM1, SIM0: SIM operating mode control
000: SPI master mode; SPI clock is fSYS/4
001: SPI master mode; SPI clock is fSYS/16
010: SPI master mode; SPI clock is fSYS/64
011: SPI master mode; SPI clock is fTBC
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 TM0. If the SPI Slave Mode is selected then
the clock will be supplied by an external Master device.
Bit 4PCKEN: PCK output pin control
0: Disable
1: Enable
Bit 3~2
PCKP1, PCKP0: select PCK output pin frequency
00: fSYS
01: fSYS/4
10: fSYS/8
11: TM0 CCRP match frequency/2
Bit 1SIMEN: SIM control
0: Disable
1: Enable
The bit is the overall on/off control for the SIM interface. When the SIMEN bit is
cleared to zero to disable the SIM interface, the SDI, SDO, SCK and SCS, or SDA
and SCL lines will be in a floating condition and the SIM operating current will be
reduced to a minimum value. When the bit is high the SIM interface is enabled. The
SIM configuration option must have first enabled the SIM interface for this bit to be
effective. Note that when the SIMEN bit changes from low to high the contents of the
SPI control registers will be in an unknown condition and should therefore be first
initialised by the application program.
Bit 0
Rev. 1.30
unimplemented, read as "0"
160
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
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. These devices contain several external
interrupt and internal interrupts functions. The external interrupts are generated by the action of the
external INT0~INT1 and PINT pins, while the internal interrupts are generated by various internal
functions such as the TMs, Comparators,Time Base, LVD, EEPROM, SIM and the A/D converter.
Interrupt Registers
Overall interrupt control, which basically means the setting of request flags when certain
microcontroller conditions occur and the setting of interrupt enable bits by the application program,
is controlled by a series of registers, located in the Special Purpose Data Memory, as shown in the
accompanying table. The number of registers depends upon the device chosen but fall into three
categories. The first is the INTC0~INTC2 registers which setup the primary interrupts, the second
is the MFI0~MFI2 registers which setup the Multi-function interrupts. Finally there is an INTEG
register to setup the external interrupt trigger edge type.
Each register contains a number of enable bits to enable or disable individual registers as well as
interrupt flags to indicate the presence of an interrupt request. The naming convention of these
follows a specific pattern. First is listed an abbreviated interrupt type, then the (optional) number of
that interrupt followed by either an “E” for enable/disable bit or “F” for request flag.
Function
Global
Enable Bit
Request Flag
EMI
—
Comparator
CPnE
CPnF
INTn Pin
INTnE
INTnF
A/D Converter
ADE
ADF
Notes
—
n=0 or 1
n=0~1
HT66F20-1/HT66F30-1 only
Multi-function
MFnE
MFnF
n=0~3
Time Base
TBnE
TBnF
n=0 or 1
SIM
SIME
SIMF
—
LVD
LVE
LVF
—
EEPROM
DEE
DEF
—
PINT Pin
XPE
XPF
—
TnPE
TnPF
TnAE
TnAF
TnBE
TnBF
TM
n=0~1
n=1
Interrupt Register Bit Naming Conventions
Rev. 1.30
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HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
Interrupt Register Contents
• HT66F20-1
Name
Bit
7
6
5
4
3
2
1
0
INTEG
—
—
—
—
INT1S1
INT1S0
INT0S1
INT0S0
INTC0
—
CP0F
INT1F
INT0F
CP0E
INT1E
INT0E
EMI
INTC1
ADF
MF1F
MF0F
CP1F
ADE
MF1E
MF0E
CP1E
INTC2
MF3F
TB1F
TB0F
MF2F
MF3E
TB1E
TB0E
MF2E
MFI0
—
—
T0AF
T0PF
—
—
T0AE
T0PE
MFI1
—
—
T1AF
T1PF
—
—
T1AE
T1PE
MFI2
DEF
LVF
XPF
SIMF
DEE
LVE
XPE
SIME
• HT66F30-1
Name
INTEG
Bit
7
6
5
4
3
2
1
0
—
—
—
—
INT1S1
INT1S0
INT0S1
INT0S0
INTC0
—
CP0F
INT1F
INT0F
CP0E
INT1E
INT0E
EMI
INTC1
ADF
MF1F
MF0F
CP1F
ADE
MF1E
MF0E
CP1E
INTC2
MF3F
TB1F
TB0F
MF2F
MF3E
TB1E
TB0E
MF2E
MFI0
—
—
T0AF
T0PF
—
—
T0AE
T0PE
MFI1
—
T1BF
T1AF
T1PF
—
T1BE
T1AE
T1PE
MFI2
DEF
LVF
XPF
SIMF
DEE
LVE
XPE
SIME
• HT68F20-1
Name
Bit
7
6
5
4
3
2
1
0
INTEG
—
—
—
—
INT1S1
INT1S0
INT0S1
INT0S0
INTC0
—
CP0F
INT1F
INT0F
CP0E
INT1E
INT0E
EMI
INTC1
—
MF1F
MF0F
CP1F
—
MF1E
MF0E
CP1E
INTC2
MF3F
TB1F
TB0F
MF2F
MF3E
TB1E
TB0E
MF2E
MFI0
—
—
T0AF
T0PF
—
—
T0AE
T0PE
MFI1
—
—
T1AF
T1PF
—
—
T1AE
T1PE
MFI2
DEF
LVF
XPF
SIMF
DEE
LVE
XPE
SIME
7
6
5
4
3
2
1
0
INT0S0
• HT68F30-1
Name
Rev. 1.30
Bit
INTEG
—
—
—
—
INT1S1
INT1S0
INT0S1
INTC0
—
CP0F
INT1F
INT0F
CP0E
INT1E
INT0E
EMI
INTC1
—
MF1F
MF0F
CP1F
—
MF1E
MF0E
CP1E
INTC2
MF3F
TB1F
TB0F
MF2F
MF3E
TB1E
TB0E
MF2E
MFI0
—
—
T0AF
T0PF
—
—
T0AE
T0PE
MFI1
—
T1BF
T1AF
T1PF
—
T1BE
T1AE
T1PE
MFI2
DEF
LVF
XPF
SIMF
DEE
LVE
XPE
SIME
162
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
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
INTC0 Register
Bit
7
6
5
4
3
2
1
0
Name
—
CP0F
INT1F
INT0F
CP0E
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 6CP0F: Comparator 0 Interrupt Request Flag
0: No request
1: Interrupt request
Bit 5INT1F: INT1 interrupt request flag
0: No request
1: Interrupt request
Bit 4INT0F: INT0 interrupt request flag
0: No request
1: Interrupt request
Bit 3CP0E: Comparator 0 Interrupt Control
0: Disable
1: Enable
Bit 2INT1E: INT1 interrupt control
0: Disable
1: Enable
Bit 1INT0E: INT0 interrupt control
0: Disable
1: Enable
Bit 0EMI: Global interrupt control
0: Disable
1: Enable
Rev. 1.30
163
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
INTC1 Register
• HT66F20-1/HT66F30-1
Bit
7
6
5
4
3
2
1
0
Name
ADF
MF1F
MF0F
CP1F
ADE
MF1E
MF0E
CP1E
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
ADF: A/D Converter Interrupt Request Flag
0: No request
1: Interrupt request
Bit 6MF1F: Multi-function Interrupt 1 Request Flag
0: No request
1: Interrupt request
Bit 5MF0F: Multi-function Interrupt 0 Request Flag
0: No request
1: Interrupt request
Bit 4CP1F: Comparator 1 Interrupt Request Flag
0: No request
1: Interrupt request
Bit 3ADE: A/D Converter Interrupt Interrupt Control
0: Disable
1: Enable
Bit 2MF1E: Multi-function Interrupt 1 Control
0: Disable
1: Enable
Bit 1MF0E: Multi-function Interrupt 0 Control
0: Disable
1: Enable
Bit 0CP1E: Comparator 1 Interrupt Control
0: Disable
1: Enable
Rev. 1.30
164
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
• HT68F20-1/HT68F30-1
Bit
7
6
5
4
Name
—
MF1F
MF0F
R/W
—
R/W
R/W
POR
—
0
0
Bit 7
3
2
1
0
CP1F
—
MF1E
MF0E
CP1E
R/W
—
R/W
R/W
R/W
0
—
0
0
0
Unimplenented, read as "0"
Bit 6MF1F: Multi-function Interrupt 1 Request Flag
0: No request
1: Interrupt request
Bit 5MF0F: Multi-function Interrupt 0 Request Flag
0: No request
1: Interrupt request
Bit 4CP1F: Comparator 1 Interrupt Request Flag
0: No request
1: Interrupt request
Bit 3
Unimplenented, read as "0"
Bit 2MF1E: Multi-function Interrupt 1 Control
0: Disable
1: Enable
Bit 1MF0E: Multi-function Interrupt 0 Control
0: Disable
1: Enable
Bit 0CP1E: Comparator 1 Interrupt Control
0: Disable
1: Enable
Rev. 1.30
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Enhanced Flash Type 8-Bit MCU with EEPROM
INTC2 Register
Bit
7
6
5
4
3
2
1
0
Name
MF3F
TB1F
TB0F
MF2F
MF3E
TB1E
TB0E
MF2E
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
0
0
0
0
0
0
0
Bit 7MF3F: Multi-function Interrupt 3 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 4MF2F: Multi-function Interrupt 2 Request Flag
0: No request
1: Interrupt request
Bit 3MF3E: Multi-function Interrupt 3 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 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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Enhanced Flash Type 8-Bit MCU with EEPROM
MFI1 Register
• HT66F20-1/HT68F20-1
Bit
7
6
5
4
3
2
1
0
Name
—
—
T1AF
T1PF
—
—
T1AE
T1PE
R/W
—
—
R/W
R/W
—
—
R/W
R/W
POR
—
—
0
0
—
—
0
0
Bit 7~6
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 3~2
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
• HT66F30-1/HT68F30-1
Bit
7
6
5
4
3
2
1
0
Name
—
T1BF
T1AF
T1PF
—
T1BE
T1AE
T1PE
R/W
—
R/W
R/W
R/W
—
R/W
R/W
R/W
POR
—
0
0
0
—
0
0
0
Bit 7
Unimplemented, read as "0"
Bit 6T1BF: TM1 Comparator B match interrupt request flag
0: no request
1: interrupt request
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 3
Unimplemented, read as "0"
Bit 2T1BE: TM1 Comparator B match interrupt control
0: disable
1: enable
Bit 1T1AE: TM1 Comparator A match interrupt control
0: disable
1: enable
Bit 0T1PE: TM1 Comparator P match interrupt control
0: disable
1: enable
Rev. 1.30
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Enhanced Flash Type 8-Bit MCU with EEPROM
MFI2 Register
Bit
7
6
5
4
3
Name
R/W
POR
2
1
0
DEF
LVF
XPF
SIMF
R/W
R/W
R/W
R/W
DEE
LVE
XPE
SIME
R/W
R/W
R/W
0
0
0
0
R/W
0
0
0
0
Bit 7DEF: Data EEPROM interrupt request flag
0: No request
1: Interrupt request
Bit 6LVF: LVD interrupt request flag
0: No request
1: Interrupt request
Bit 5XPF: External peripheral interrupt request flag
0: No request
1: Interrupt request
Bit 4SIMF: SIM interrupt request flag
0: No request
1: Interrupt request
Bit 3DEE: Data EEPROM Interrupt Control
0: Disable
1: Enable
Bit 2LVE: LVD Interrupt Control
0: Disable
1: Enable
Bit 1XPE: External Peripheral Interrupt Control
0: Disable
1: Enable
Bit 0SIME: SIM Interrupt Control
0: Disable
1: Enable
Rev. 1.30
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Enhanced Flash Type 8-Bit MCU with EEPROM
Interrupt Operation
When the conditions for an interrupt event occur, such as a TM Compare P, Compare A or Compare
B 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.
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.
Rev. 1.30
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Enhanced Flash Type 8-Bit MCU with EEPROM
EMI auto disabled in ISR
Legend
xxF Request Flag – no auto reset in ISR
xxF Request Flag – auto reset in ISR
xxE Enable Bit
Interrupt
Name
Interrupt Request
Name
Flags
Enable
Bits
Master
Enable
Vector
INT0 Pin
INT0F
INT0E
EMI
04H
INT1 Pin
INT1F
INT1E
EMI
08H
Comp. 0
CP0F
CP0E
EMI
0CH
Comp. 1
CP1F
CP1E
EMI
10H
Request
Flags
Enable
Bits
TM0 P
T0PF
T0PE
TM0 A
T0AF
T0AE
M. Funct. 0
MF0F
MF0E
EMI
14H
TM1 P
T1PF
T1PE
M. Funct. 1
MF1F
MF1E
EMI
18H
TM1 A
T1AF
T1AE
ADF
ADE
EMI
1CH
TM1 B
T1BF
T1BE
SIM
SIMF
M. Funct. 2
MF2F
MF2E
EMI
20H
Time Base 0
TB0F
TB0E
EMI
24H
Time Base 1
TB1F
TB1E
EMI
28H
M. Funct. 3
MF3F
MF3E
EMI
2CH
PINT Pin
LVD
EEPROM
XPF
A/D
SIME
XPE
LVF
LVE
DEF
DEE
Priority
High
Low
Interrupts contained within
Multi-Function Interrupts
Interrupt Structure – HT66F20-1/HT66F30-1
Rev. 1.30
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HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
EMI auto disabled in ISR
Legend
xxF Request Flag – no auto reset in ISR
xxF Request Flag – auto reset in ISR
xxE Enable Bit
Interrupt
Name
Request
Flags
Enable
Bits
Interrupt Request
Name
Flags
Enable
Bits
Master
Enable
Vector
INT0 Pin
INT0F
INT0E
EMI
04H
INT1 Pin
INT1F
INT1E
EMI
08H
Comp. 0
CP0F
CP0E
EMI
0CH
Comp. 1
CP1F
CP1E
EMI
10H
TM0 P
T0PF
T0PE
TM0 A
T0AF
T0AE
M. Funct. 0
MF0F
MF0E
EMI
14H
TM1 P
T1PF
T1PE
M. Funct. 1
MF1F
MF1E
EMI
18H
TM1 A
T1AF
T1AE
TM1 B
T1BF
T1BE
SIM
SIMF
M. Funct. 2
MF2F
MF2E
EMI
20H
Time Base 0
TB0F
TB0E
EMI
24H
Time Base 1
TB1F
TB1E
EMI
28H
M. Funct. 3
MF3F
MF3E
EMI
2CH
PINT Pin
LVD
EEPROM
XPF
SIME
XPE
LVF
LVE
DEF
DEE
Priority
High
Low
Interrupts contained within
Multi-Function Interrupts
Interrupt Structure – HT68F20-1/HT68F30-1
Rev. 1.30
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Enhanced Flash Type 8-Bit MCU with EEPROM
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.
Comparator Interrupt
The comparator interrupts are controlled by the two internal comparators. A comparator interrupt
request will take place when the comparator interrupt request flags, CP0F or CP1F, are set, a
situation that will occur when the comparator output changes state. To allow the program to branch
to its respective interrupt vector address, the global interrupt enable bit, EMI, and comparator
interrupt enable bits, CP0E and CP1E, must first be set. When the interrupt is enabled, the stack is
not full and the comparator inputs generate a comparator output transition, a subroutine call to the
comparator interrupt vector, will take place. When the interrupt is serviced, the comparator interrupt
request flags, CP0F and CP1F, will be automatically reset and the EMI bit will be automatically
cleared to disable other interrupts.
Multi-function Interrupt
Within these devices are 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, SIM Interrupt, External Peripheral Interrupt, LVD interrupt and
EEPROM Interrupt.
A Multi-function interrupt request will take place when any of the Multi-function interrupt request
flags, MF0F~MF3F 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, SIM Interrupt, External Peripheral Interrupt, LVD interrupt
and EEPROM Interrupt will not be automatically reset and must be manually reset by the application
program.
Rev. 1.30
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HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
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.
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.
Rev. 1.30
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Enhanced Flash Type 8-Bit MCU with EEPROM
TBC Register
Bit
7
6
5
4
3
2
1
0
Name
TBON
TBCK
TB11
TB10
LXTLP
TB02
TB01
TB00
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
0
1
1
0
1
1
1
Bit 7TBON: TB0 and TB1 Control
0: Disable
1: Enable
Bit 6TBCK: Select fTB Clock
0: fTBC
1: fSYS/4
Bit 5~4TB11~TB10: Select Time Base 1 Time-out Period
00: 4096/fTB
01: 8192/fTB
10: 16384/fTB
11: 32768/fTB
Bit 3LXTLP: LXT Low Power Control
0: Disable
1: Enable
Bit 2~0TB02~TB00: Select Time Base 0 Time-out Period
000: 256/fTB
001: 512/fTB
010: 1024/fTB
011: 2048/fTB
100: 4096/fTB
101: 8192/fTB
110: 16384/fTB
111: 32768/fTB
      Time Base Interrupts
Rev. 1.30
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May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
Serial Interface Module Interrupts
The Serial Interface Module Interrupt, also known as the SIM interrupt, is contained within the
Multi-function Interrupt. A SIM Interrupt request will take place when the SIM Interrupt request
flag, SIMF, is set, which occurs when a byte of data has been received or transmitted by the SIM
interface. To allow the program to branch to its respective interrupt vector address, the global
interrupt enable bit, EMI, and the Serial Interface Interrupt enable bit, SIME, 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 SIMF flag will not be automatically
cleared, it has to be cleared by the application program.
External Peripheral Interrupt
The External Peripheral Interrupt operates in a similar way to the external interrupt and is contained
within the Multi-function Interrupt. A Peripheral Interrupt request will take place when the External
Peripheral Interrupt request flag, XPF, is set, which occurs when a negative edge transition appears
on the PINT pin. To allow the program to branch to its respective interrupt vector address, the
global interrupt enable bit, EMI, external peripheral interrupt enable bit, XPE, and associated
Multi-function interrupt enable bit, must first be set. When the interrupt is enabled, the stack is not
full and a negative transition appears on the External Peripheral Interrupt pin, a subroutine call to
the respective Multi-function Interrupt, will take place. When the External Peripheral 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 XPF flag will not be automatically cleared, it has to be cleared by the application program.
The external peripheral interrupt pin is pin-shared with several other pins with different functions. It
must therefore be properly configured to enable it to operate as an External Peripheral Interrupt pin.
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 or read cycle ends. To allow the program to branch to its respective interrupt vector
address, the global interrupt enable bit, EMI, 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 or read cycle ends, a subroutine call to the respective Multi-function
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.
Rev. 1.30
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HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
LVD Interrupt
The Low Voltage Detector Interrupt is contained within the Multi-function Interrupt. An LVD
Interrupt request will take place when the LVD Interrupt request flag, LVF, is set, which occurs
when the Low Voltage Detector function detects a low power supply voltage. To allow the program
to branch to its respective interrupt vector address, the global interrupt enable bit, EMI, Low Voltage
Interrupt enable bit, LVE, and associated Multi-function interrupt enable bit, must first be set. When
the interrupt is enabled, the stack is not full and a low voltage condition occurs, a subroutine call to
the Multi-function Interrupt vector, will take place. When the Low Voltage Interrupt is serviced, the
EMI bit will be automatically cleared to disable other interrupts, however only the Multi-function
interrupt request flag will be also automatically cleared. As the LVF flag will not be automatically
cleared, it has to be cleared by the application program.
TM Interrupts
The Compact and Standard TM each has two interrupts, while the Enhanced Type TM has three
interrupts. All of the TM interrupts are contained within the Multi-function Interrupts. For the
Compact and Standard Type TM there are two interrupt request flags TnPF and TnAF and two
enable bits TnPE and TnAE. For the Enhanced Type TM there are three interrupt request flags TnPF,
TnAF and TnBF and three enable bits TnPE, TnAE and TnBE. 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, A
or B match situation happens.
To allow the program to branch to its respective interrupt vector address, the global interrupt enable
bit, EMI, respective TM Interrupt enable bit, and relevant Multi-function Interrupt enable bit, MFnE,
must first be set. When the interrupt is enabled, the stack is not full and a TM comparator match
situation occurs, a subroutine call to the relevant Multi-function Interrupt vector locations, will take
place. When the TM interrupt is serviced, the EMI bit will be automatically cleared to disable other
interrupts, however only the related MFnF flag will be automatically cleared. As the TM interrupt
request flags will not be automatically cleared, they have to be cleared by the application program.
Interrupt Wake-up Function
Each of the interrupt functions has the capability of waking up the microcontroller when in the
SLEEP or IDLE Mode. A wake-up is generated when an interrupt request flag changes from low
to high and is independent of whether the interrupt is enabled or not. Therefore, even though these
devices are in the SLEEP or IDLE Mode and its system oscillator stopped, situations such as
external edge transitions on the external interrupt pins, a low power supply voltage or comparator
input change may cause their respective interrupt flag to be set high and consequently generate
an interrupt. Care must therefore be taken if spurious wake-up situations are to be avoided. If an
interrupt wake-up function is to be disabled then the corresponding interrupt request flag should be
set high before the device enters the SLEEP or IDLE Mode. The interrupt enable bits have no effect
on the interrupt wake-up function.
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Enhanced Flash Type 8-Bit MCU with EEPROM
Programming Considerations
By disabling the relevant interrupt enable bits, a requested interrupt can be prevented from being
serviced, however, once an interrupt request flag is set, it will remain in this condition in the
interrupt register until the corresponding interrupt is serviced or until the request flag is cleared by
the application program.
Where a certain interrupt is contained within a Multi-function interrupt, then when the interrupt
service routine is executed, as only the Multi-function interrupt request flags, MF0F~MF3F, will
be automatically cleared, the individual request flag for the function needs to be cleared by the
application program.
It is recommended that programs do not use the “CALL” instruction within the interrupt service
subroutine. Interrupts often occur in an unpredictable manner or need to be serviced immediately.
If only one stack is left and the interrupt is not well controlled, the original control sequence will be
damaged once a CALL subroutine is executed in the interrupt subroutine.
Every interrupt has the capability of waking up the microcontroller when it is in the SLEEP or IDLE
Mode, the wake up being generated when the interrupt request flag changes from low to high. If it is
required to prevent a certain interrupt from waking up the microcontroller then its respective request
flag should be first set high before enter SLEEP or IDLE Mode.
As only the Program Counter is pushed onto the stack, then when the interrupt is serviced, if the
contents of the accumulator, status register or other registers are altered by the interrupt service
program, their contents should be saved to the memory at the beginning of the interrupt service
routine.
To return from an interrupt subroutine, either a RET or RETI instruction may be executed. The RETI
instruction in addition to executing a return to the main program also automatically sets the EMI
bit high to allow further interrupts. The RET instruction however only executes a return to the main
program leaving the EMI bit in its present zero state and therefore disabling the execution of further
interrupts.
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Enhanced Flash Type 8-Bit MCU with EEPROM
Low Voltage Detector – LVD
Each device has a Low Voltage Detector function, also known as LVD. This enabled the device to
monitor the power supply voltage, VDD, and provide a warning signal should it fall below a certain
level. This function may be especially useful in battery applications where the supply voltage will
gradually reduce as the battery ages, as it allows an early warning battery low signal to be generated.
The Low Voltage Detector also has the capability of generating an interrupt signal.
LVD Register
The Low Voltage Detector function is controlled using a single register with the name LVDC. Three
bits in this register, VLVD2~VLVD0, are used to select one of eight fixed voltages below which
a low voltage condition will be determined. A low voltage condition is indicated when the LVDO
bit is set. If the LVDO bit is low, this indicates that the VDD voltage is above the preset low voltage
value. The LVDEN bit is used to control the overall on/off function of the low voltage detector.
Setting the bit high will enable the low voltage detector. Clearing the bit to zero will switch off the
internal low voltage detector circuits. As the low voltage detector will consume a certain amount of
power, it may be desirable to switch off the circuit when not in use, an important consideration in
power sensitive battery powered applications.
LVDC Register
Bit
7
6
5
4
3
2
1
0
Name
—
—
LVDO
LVDEN
—
VLVD2
VLVD1
VLVD0
R/W
—
—
R
R/W
—
R/W
R/W
R/W
POR
—
—
0
0
—
0
0
0
Bit 7~6
Unimplemented, read as "0"
Bit 5LVDO: LVD Output Flag
0: No Low Voltage Detect
1: Low Voltage Detect
Bit 4LVDEN: Low Voltage Detector Control
0: Disable
1: Enable
Bit 3
Unimplemented, read as "0"
Bit 2~0VLVD2~VLVD0: Select LVD Voltage
000: 2.0V
001: 2.2V
010: 2.4V
011: 2.7V
100: 3.0V
101: 3.3V
110: 3.6V
111: 4.4V
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Enhanced Flash Type 8-Bit MCU with EEPROM
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 4.4V.
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.
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Enhanced Flash Type 8-Bit MCU with EEPROM
SCOM Function for LCD
The devices have the capability of driving external LCD panels. The common pins for LCD driving,
SCOM0~SCOM3, are pin shared with certain pin on the PC0~PC1, PC6~PC7 port. The LCD
signals (COM and SEG) are generated using the application program.
LCD Operation
An external LCD panel can be driven using this device by configuring the PC0~PC1, PC6~PC7
pins as common pins and using other output ports lines as segment pins. The LCD driver function
is controlled using the SCOMC register which in addition to controlling the overall on/off function
also controls the bias voltage setup function. This enables the LCD COM driver to generate the
necessary VDD/2 voltage levels for LCD 1/2 bias operation.
The SCOMEN bit in the SCOMC register is the overall master control for the LCD driver, however
this bit is used in conjunction with the COMnEN bits to select which Port C pins are used for LCD
driving. Note that the Port Control register does not need to first setup the pins as outputs to enable
the LCD driver operation.
LCD COM Bias
SCOMEN
COMnEN
Pin Function
O/P Level
0
X
I/O
0 or 1
1
0
I/O
0 or 1
1
1
SCOMn
VDD/2
Output Control
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Enhanced Flash Type 8-Bit MCU with EEPROM
LCD Bias Control
The LCD COM driver enables a range of selections to be provided to suit the requirement of the
LCD panel which is being used. The bias resistor choice is implemented using the ISEL1 and ISEL0
bits in the SCOMC register.
SCOMC Register
• HT66F30-1/HT68F30-1
Bit
7
6
5
4
3
2
1
0
Name
D7
ISEL1
ISEL0
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
SCOMEN COM3EN COM2EN COM1EN COM0EN
Bit 7
Reserved Bit
0: Correct level - bit must be reset to zero for correct operation
1: Unpredictable operation - bit must not be set high
Bit 6~5
ISEL1, ISEL0: Select SCOM typical bias current (VDD=5V)
00: 25μA
01: 50μA
10: 100μA
11: 200μA
Bit 4SCOMEN: SCOM module Control
0: Disable
1: Enable
Bit 3COM3EN: PC7 or SCOM3 selection
0: GPIO
1: SCOM3
Bit 2COM2EN: PC6 or SCOM2 selection
0: GPIO
1: SCOM2
Bit 1COM1EN: PC1 or SCOM1 selection
0: GPIO
1: SCOM1
Bit 0COM0EN: PC0 or SCOM0 selection
0: GPIO
1: SCOM0
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Enhanced Flash Type 8-Bit MCU with EEPROM
Configuration Options
Configuration options refer to certain options within the MCU that are programmed into the devices
during the programming process. During the development process, these options are selected using
the HT-IDE software development tools. As these options are programmed into the devices using
the hardware programming tools, once they are selected they cannot be changed later using the
application program. All options must be defined for proper system function, the details of which are
shown in the table.
No.
Options
Oscillator Options
1
High Speed System Oscillator Selection - fH:
1. HXT
2. ERC
3. HIRC
2
Low Speed System Oscillator Selection - fSUB:
1. LXT
2. LIRC
3
WDT Clock Selection - fS:
1. fSUB
2. fSYS/4
4
HIRC Frequency Selection:
1. 4MHz
2. 8MHz
3. 12MHz
Note: The fSUB and the fTBC clock source are LXT or LIRC selection by the fL configuration option.
Reset Pin Options
5
PB0/RES Pin Options:
1. RES pin
2. I/O pin
Watchdog Options
6
Watchdog Timer Function:
1. Enable
2. Disable
7
CLR WDT Instructions Selection:
1. 1 instructions
2. 2 instructions
LVR Options
8
LVR Function:
1. Enable
2. Disable
9
LVR Voltage Selection:
1. 2.10V
2. 2.55V
3. 3.15V
4. 4.20V
SIM Options
Rev. 1.30
10
SIM Function:
1. Enable
2. Disable
11
SPI - WCOL bit:
1. Enable
2. Disable
12
SPI - CSEN bit:
1. Enable
2. Disable
13
I2C Debounce Time Selection:
1. No debounce
2. 2 system clock debounce
3. 4 system clock debounce
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Enhanced Flash Type 8-Bit MCU with EEPROM
Application Circuits
HT66F20-1/HT66F30-1
V
D D
0 .0 1 F * *
0 .1 F
V D D
1 0 k ~
1 0 0 k 1 N 4 1 4 8 *
0 .1 ~ 1 F
3 0 0 *
R E S
A N 0 ~ A N 7
P B 0 ~ P B 5
V S S
O S C
C ir c u it
P C 0 ~ P C 7
O S C 1
O S C 2
O S C
C ir c u it
X T 1
X T 2
Note: "*": It is recommended that this component is added for added ESD protection.
"**": It is recommended that this component is added in environments where power line
noise is significant.
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Enhanced Flash Type 8-Bit MCU with EEPROM
HT68F20-1/HT68F30-1
V
D D
0 .0 1 F * *
0 .1 F
V D D
1 0 k ~
1 0 0 k 1 N 4 1 4 8 *
0 .1 ~ 1 F
3 0 0 *
R E S
P A 0 ~ P A 7
P B 0 ~ P B 5
V S S
P C 0 ~ P C 7
O S C 1
O S C
C ir c u it
O S C 2
X T 1
O S C
C ir c u it
X T 2
Note: "*": It is recommended that this component is added for added ESD protection.
"**": It is recommended that this component is added in environments where power line
noise is significant.
Rev. 1.30
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Enhanced Flash Type 8-Bit MCU with EEPROM
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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Enhanced Flash Type 8-Bit MCU with EEPROM
Logical and Rotate Operation
The standard logical operations such as AND, OR, XOR and CPL all have their own instruction
within the Holtek microcontroller instruction set. As with the case of most instructions involving
data manipulation, data must pass through the Accumulator which may involve additional
programming steps. In all logical data operations, the zero flag may be set if the result of the
operation is zero. Another form of logical data manipulation comes from the rotate instructions such
as RR, RL, RRC and RLC which provide a simple means of rotating one bit right or left. Different
rotate instructions exist depending on program requirements. Rotate instructions are useful for serial
port programming applications where data can be rotated from an internal register into the Carry
bit from where it can be examined and the necessary serial bit set high or low. Another application
which rotate data operations are used is to implement multiplication and division calculations.
Branches and Control Transfer
Program branching takes the form of either jumps to specified locations using the JMP instruction
or to a subroutine using the CALL instruction. They differ in the sense that in the case of a
subroutine call, the program must return to the instruction immediately when the subroutine has
been carried out. This is done by placing a return instruction “RET” in the subroutine which will
cause the program to jump back to the address right after the CALL instruction. In the case of a JMP
instruction, the program simply jumps to the desired location. There is no requirement to jump back
to the original jumping off point as in the case of the CALL instruction. One special and extremely
useful set of branch instructions are the conditional branches. Here a decision is first made regarding
the condition of a certain data memory or individual bits. Depending upon the conditions, the
program will continue with the next instruction or skip over it and jump to the following instruction.
These instructions are the key to decision making and branching within the program perhaps
determined by the condition of certain input switches or by the condition of internal data bits.
Bit Operations
The ability to provide single bit operations on Data Memory is an extremely flexible feature of all
Holtek microcontrollers. This feature is especially useful for output port bit programming where
individual bits or port pins can be directly set high or low using either the “SET [m].i” or “CLR [m].i”
instructions respectively. The feature removes the need for programmers to first read the 8-bit output
port, manipulate the input data to ensure that other bits are not changed and then output the port with
the correct new data. This read-modify-write process is taken care of automatically when these bit
operation instructions are used.
Table Read Operations
Data storage is normally implemented by using registers. However, when working with large
amounts of fixed data, the volume involved often makes it inconvenient to store the fixed data in
the Data Memory. To overcome this problem, Holtek microcontrollers allow an area of Program
Memory to be setup as a table where data can be directly stored. A set of easy to use instructions
provides the means by which this fixed data can be referenced and retrieved from the Program
Memory.
Other Operations
In addition to the above functional instructions, a range of other instructions also exist such as
the “HALT” instruction for Power-down operations and instructions to control the operation of
the Watchdog Timer for reliable program operations under extreme electric or electromagnetic
environments. For their relevant operations, refer to the functional related sections.
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Enhanced Flash Type 8-Bit MCU with EEPROM
Instruction Set Summary
The following table depicts a summary of the instruction set categorised according to function and
can be consulted as a basic instruction reference using the following listed conventions.
Table Conventions
x: Bits immediate data
m: Data Memory address
A: Accumulator
i: 0~7 number of bits
addr: Program memory address
Mnemonic
Description
Cycles
Flag Affected
Add Data Memory to ACC
Add ACC to Data Memory
Add immediate data to ACC
Add Data Memory to ACC with Carry
Add ACC to Data memory with Carry
Subtract immediate data from the ACC
Subtract Data Memory from ACC
Subtract Data Memory from ACC with result in Data Memory
Subtract Data Memory from ACC with Carry
Subtract Data Memory from ACC with Carry, result in Data Memory
Decimal adjust ACC for Addition with result in Data Memory
1
1Note
1
1
1Note
1
1
1Note
1
1Note
1Note
Z, C, AC, OV
Z, C, AC, OV
Z, C, AC, OV
Z, C, AC, OV
Z, C, AC, OV
Z, C, AC, OV
Z, C, AC, OV
Z, C, AC, OV
Z, C, AC, OV
Z, C, AC, OV
C
1
1
1
1Note
1Note
1Note
1
1
1
1Note
1
Z
Z
Z
Z
Z
Z
Z
Z
Z
Z
Z
Increment Data Memory with result in ACC
Increment Data Memory
Decrement Data Memory with result in ACC
Decrement Data Memory
1
1Note
1
1Note
Z
Z
Z
Z
Rotate Data Memory right with result in ACC
Rotate Data Memory right
Rotate Data Memory right through Carry with result in ACC
Rotate Data Memory right through Carry
Rotate Data Memory left with result in ACC
Rotate Data Memory left
Rotate Data Memory left through Carry with result in ACC
Rotate Data Memory left through Carry
1
1Note
1
1Note
1
1Note
1
1Note
None
None
C
C
None
None
C
C
Arithmetic
ADD A,[m]
ADDM A,[m]
ADD A,x
ADC A,[m]
ADCM A,[m]
SUB A,x
SUB A,[m]
SUBM A,[m]
SBC A,[m]
SBCM A,[m]
DAA [m]
Logic Operation
AND A,[m]
OR A,[m]
XOR A,[m]
ANDM A,[m]
ORM A,[m]
XORM A,[m]
AND A,x
OR A,x
XOR A,x
CPL [m]
CPLA [m]
Logical AND Data Memory to ACC
Logical OR Data Memory to ACC
Logical XOR Data Memory to ACC
Logical AND ACC to Data Memory
Logical OR ACC to Data Memory
Logical XOR ACC to Data Memory
Logical AND immediate Data to ACC
Logical OR immediate Data to ACC
Logical XOR immediate Data to ACC
Complement Data Memory
Complement Data Memory with result in ACC
Increment & Decrement
INCA [m]
INC [m]
DECA [m]
DEC [m]
Rotate
RRA [m]
RR [m]
RRCA [m]
RRC [m]
RLA [m]
RL [m]
RLCA [m]
RLC [m]
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Enhanced Flash Type 8-Bit MCU with EEPROM
Mnemonic
Description
Cycles
Flag Affected
Move Data Memory to ACC
Move ACC to Data Memory
Move immediate data to ACC
1
1Note
1
None
None
None
Clear bit of Data Memory
Set bit of Data Memory
1Note
1Note
None
None
Jump unconditionally
Skip if Data Memory is zero
Skip if Data Memory is zero with data movement to ACC
Skip if bit i of Data Memory is zero
Skip if bit i of Data Memory is not zero
Skip if increment Data Memory is zero
Skip if decrement Data Memory is zero
Skip if increment Data Memory is zero with result in ACC
Skip if decrement Data Memory is zero with result in ACC
Subroutine call
Return from subroutine
Return from subroutine and load immediate data to ACC
Return from interrupt
2
1Note
1Note
1Note
1Note
1Note
1Note
1Note
1Note
2
2
2
2
None
None
None
None
None
None
None
None
None
None
None
None
None
Read table to TBLH and Data Memory
Read table (last page) to TBLH and Data Memory
2Note
2Note
None
None
No operation
Clear Data Memory
Set Data Memory
Clear Watchdog Timer
Pre-clear Watchdog Timer
Pre-clear Watchdog Timer
Swap nibbles of Data Memory
Swap nibbles of Data Memory with result in ACC
Enter power down mode
1
1Note
1Note
1
1
1
1Note
1
1
None
None
None
TO, PDF
TO, PDF
TO, PDF
None
None
TO, PDF
Data Move
MOV A,[m]
MOV [m],A
MOV A,x
Bit Operation
CLR [m].i
SET [m].i
Branch
JMP addr
SZ [m]
SZA [m]
SZ [m].i
SNZ [m].i
SIZ [m]
SDZ [m]
SIZA [m]
SDZA [m]
CALL addr
RET
RET A,x
RETI
Table Read
TABRDC [m]
TABRDL [m]
Miscellaneous
NOP
CLR [m]
SET [m]
CLR WDT
CLR WDT1
CLR WDT2
SWAP [m]
SWAPA [m]
HALT
Note: 1. For skip instructions, if the result of the comparison involves a skip then two cycles are required, if no
skip takes place only one cycle is required.
2. Any instruction which changes the contents of the PCL will also require 2 cycles for execution.
3. For the “CLR WDT1” and “CLR WDT2” instructions the TO and PDF flags may be affected by the
execution status. The TO and PDF flags are cleared after both “CLR WDT1” and “CLR WDT2”
instructions are consecutively executed. Otherwise the TO and PDF flags remain unchanged.
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Enhanced Flash Type 8-Bit MCU with EEPROM
Instruction Definition
ADC A,[m]
Description
Operation
Affected flag(s)
Add Data Memory to ACC with Carry
The contents of the specified Data Memory, Accumulator and the carry flag are added.
The result is stored in the Accumulator.
ACC ← ACC + [m] + C
OV, Z, AC, C
ADCM A,[m]
Description
Operation
Affected flag(s)
Add ACC to Data Memory with Carry
The contents of the specified Data Memory, Accumulator and the carry flag are added. The result is stored in the specified Data Memory.
[m] ← ACC + [m] + C
OV, Z, AC, C
Add Data Memory to ACC
ADD A,[m]
Description
The contents of the specified Data Memory and the Accumulator are added.
The result is stored in the Accumulator.
Operation
Affected flag(s)
ACC ← ACC + [m]
OV, Z, AC, C
ADD A,x
Description
Operation
Affected flag(s)
Add immediate data to ACC
The contents of the Accumulator and the specified immediate data are added. The result is stored in the Accumulator.
ACC ← ACC + x
OV, Z, AC, C
ADDM A,[m]
Description
Operation
Affected flag(s)
Add ACC to Data Memory
The contents of the specified Data Memory and the Accumulator are added. The result is stored in the specified Data Memory.
[m] ← ACC + [m]
OV, Z, AC, C
AND A,[m]
Description
Operation
Affected flag(s)
Logical AND Data Memory to ACC
Data in the Accumulator and the specified Data Memory perform a bitwise logical AND operation. The result is stored in the Accumulator.
ACC ← ACC ″AND″ [m]
Z
AND A,x
Description
Operation
Affected flag(s)
Logical AND immediate data to ACC
Data in the Accumulator and the specified immediate data perform a bit wise logical AND operation. The result is stored in the Accumulator.
ACC ← ACC ″AND″ x
Z
ANDM A,[m]
Description
Operation
Affected flag(s)
Logical AND ACC to Data Memory
Data in the specified Data Memory and the Accumulator perform a bitwise logical AND
operation. The result is stored in the Data Memory.
[m] ← ACC ″AND″ [m]
Z
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Enhanced Flash Type 8-Bit MCU with EEPROM
CALL addr
Description
Operation
Affected flag(s)
Subroutine call
Unconditionally calls a subroutine at the specified address. The Program Counter then
increments by 1 to obtain the address of the next instruction which is then pushed onto the
stack. The specified address is then loaded and the program continues execution from this
new address. As this instruction requires an additional operation, it is a two cycle instruction.
Stack ← Program Counter + 1
Program Counter ← addr
None
CLR [m]
Description
Operation
Affected flag(s)
Clear Data Memory
Each bit of the specified Data Memory is cleared to 0.
[m] ← 00H
None
CLR [m].i
Description
Operation
Affected flag(s)
Clear bit of Data Memory
Bit i of the specified Data Memory is cleared to 0.
[m].i ← 0
None
CLR WDT
Description
Operation
Affected flag(s)
Clear Watchdog Timer
The TO, PDF flags and the WDT are all cleared.
WDT cleared
TO ← 0
PDF ← 0
TO, PDF
CLR WDT1
Description
Operation
Affected flag(s)
Pre-clear Watchdog Timer
The TO, PDF flags and the WDT are all cleared. Note that this instruction works in
conjunction with CLR WDT2 and must be executed alternately with CLR WDT2 to have
effect. Repetitively executing this instruction without alternately executing CLR WDT2 will
have no effect.
WDT cleared
TO ← 0
PDF ← 0
TO, PDF
CLR WDT2
Description
Operation
Affected flag(s)
Pre-clear Watchdog Timer
The TO, PDF flags and the WDT are all cleared. Note that this instruction works in conjunction
with CLR WDT1 and must be executed alternately with CLR WDT1 to have effect.
Repetitively executing this instruction without alternately executing CLR WDT1 will have no
effect.
WDT cleared
TO ← 0
PDF ← 0
TO, PDF
CPL [m]
Description
Operation
Affected flag(s)
Complement Data Memory
Each bit of the specified Data Memory is logically complemented (1′s complement). Bits which
previously contained a 1 are changed to 0 and vice versa.
[m] ← [m]
Z
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Enhanced Flash Type 8-Bit MCU with EEPROM
CPLA [m]
Description
Operation
Affected flag(s)
Complement Data Memory with result in ACC
Each bit of the specified Data Memory is logically complemented (1′s complement). Bits which
previously contained a 1 are changed to 0 and vice versa. The complemented result is stored in
the Accumulator and the contents of the Data Memory remain unchanged.
ACC ← [m]
Z
DAA [m]
Description
Operation
Affected flag(s)
Decimal-Adjust ACC for addition with result in Data Memory
Convert the contents of the Accumulator value to a BCD (Binary Coded Decimal) value
resulting from the previous addition of two BCD variables. If the low nibble is greater than 9
or if AC flag is set, then a value of 6 will be added to the low nibble. Otherwise the low nibble
remains unchanged. If the high nibble is greater than 9 or if the C flag is set, then a value of 6
will be added to the high nibble. Essentially, the decimal conversion is performed by adding
00H, 06H, 60H or 66H depending on the Accumulator and flag conditions. Only the C flag
may be affected by this instruction which indicates that if the original BCD sum is greater than
100, it allows multiple precision decimal addition.
[m] ← ACC + 00H or
[m] ← ACC + 06H or [m] ← ACC + 60H or
[m] ← ACC + 66H
C
DEC [m]
Description
Operation
Affected flag(s)
Decrement Data Memory
Data in the specified Data Memory is decremented by 1.
[m] ← [m] − 1
Z
DECA [m]
Description
Operation
Affected flag(s)
Decrement Data Memory with result in ACC
Data in the specified Data Memory is decremented by 1. The result is stored in the
Accumulator. The contents of the Data Memory remain unchanged.
ACC ← [m] − 1
Z
HALT
Description
Operation
Affected flag(s)
Enter power down mode
This instruction stops the program execution and turns off the system clock. The contents of the Data Memory and registers are retained. The WDT and prescaler are cleared. The power
down flag PDF is set and the WDT time-out flag TO is cleared.
TO ← 0
PDF ← 1
TO, PDF
INC [m]
Description
Operation
Affected flag(s)
Increment Data Memory
Data in the specified Data Memory is incremented by 1.
[m] ← [m] + 1
Z
INCA [m]
Description
Operation
Affected flag(s)
Increment Data Memory with result in ACC
Data in the specified Data Memory is incremented by 1. The result is stored in the Accumulator.
The contents of the Data Memory remain unchanged.
ACC ← [m] + 1
Z
Rev. 1.30
191
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
JMP addr
Description
Operation
Affected flag(s)
Jump unconditionally
The contents of the Program Counter are replaced with the specified address. Program
execution then continues from this new address. As this requires the insertion of a dummy
instruction while the new address is loaded, it is a two cycle instruction.
Program Counter ← addr
None
MOV A,[m]
Description
Operation
Affected flag(s)
Move Data Memory to ACC
The contents of the specified Data Memory are copied to the Accumulator.
ACC ← [m]
None
MOV A,x
Description
Operation
Affected flag(s)
Move immediate data to ACC
The immediate data specified is loaded into the Accumulator.
ACC ← x
None
MOV [m],A
Description
Operation
Affected flag(s)
Move ACC to Data Memory
The contents of the Accumulator are copied to the specified Data Memory.
[m] ← ACC
None
NOP
Description
Operation
Affected flag(s)
No operation
No operation is performed. Execution continues with the next instruction.
No operation
None
OR A,[m]
Description
Operation
Affected flag(s)
Logical OR Data Memory to ACC
Data in the Accumulator and the specified Data Memory perform a bitwise
logical OR operation. The result is stored in the Accumulator.
ACC ← ACC ″OR″ [m]
Z
OR A,x
Description
Operation
Affected flag(s)
Logical OR immediate data to ACC
Data in the Accumulator and the specified immediate data perform a bitwise logical OR operation. The result is stored in the Accumulator.
ACC ← ACC ″OR″ x
Z
ORM A,[m]
Description
Operation
Affected flag(s)
Logical OR ACC to Data Memory
Data in the specified Data Memory and the Accumulator perform a bitwise logical OR operation. The result is stored in the Data Memory.
[m] ← ACC ″OR″ [m]
Z
RET
Description
Operation
Affected flag(s)
Return from subroutine
The Program Counter is restored from the stack. Program execution continues at the restored
address.
Program Counter ← Stack
None
Rev. 1.30
192
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
RET A,x
Description
Operation
Affected flag(s)
Return from subroutine and load immediate data to ACC
The Program Counter is restored from the stack and the Accumulator loaded with the specified immediate data. Program execution continues at the restored address.
Program Counter ← Stack
ACC ← x
None
RETI
Description
Operation
Affected flag(s)
Return from interrupt
The Program Counter is restored from the stack and the interrupts are re-enabled by setting the
EMI bit. EMI is the master interrupt global enable bit. If an interrupt was pending when the RETI instruction is executed, the pending Interrupt routine will be processed before returning to the main program.
Program Counter ← Stack
EMI ← 1
None
RL [m]
Description
Operation
Affected flag(s)
Rotate Data Memory left
The contents of the specified Data Memory are rotated left by 1 bit with bit 7 rotated into bit 0.
[m].(i+1) ← [m].i; (i=0~6)
[m].0 ← [m].7
None
RLA [m]
Description
Operation
Affected flag(s)
Rotate Data Memory left with result in ACC
The contents of the specified Data Memory are rotated left by 1 bit with bit 7 rotated into bit 0.
The rotated result is stored in the Accumulator and the contents of the Data Memory remain
unchanged.
ACC.(i+1) ← [m].i; (i=0~6)
ACC.0 ← [m].7
None
RLC [m]
Description
Operation
Affected flag(s)
Rotate Data Memory left through Carry
The contents of the specified Data Memory and the carry flag are rotated left by 1 bit. Bit 7
replaces the Carry bit and the original carry flag is rotated into bit 0.
[m].(i+1) ← [m].i; (i=0~6)
[m].0 ← C
C ← [m].7
C
RLCA [m]
Description
Operation
Affected flag(s)
Rotate Data Memory left through Carry with result in ACC
Data in the specified Data Memory and the carry flag are rotated left by 1 bit. Bit 7 replaces the
Carry bit and the original carry flag is rotated into the bit 0. The rotated result is stored in the
Accumulator and the contents of the Data Memory remain unchanged.
ACC.(i+1) ← [m].i; (i=0~6)
ACC.0 ← C
C ← [m].7
C
RR [m]
Description
Operation
Affected flag(s)
Rotate Data Memory right
The contents of the specified Data Memory are rotated right by 1 bit with bit 0 rotated into bit 7.
[m].i ← [m].(i+1); (i=0~6)
[m].7 ← [m].0
None
Rev. 1.30
193
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
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
RRCA [m]
Description
Operation
Affected flag(s)
Rotate Data Memory right through Carry with result in ACC
Data in the specified Data Memory and the carry flag are rotated right by 1 bit. Bit 0 replaces the Carry bit and the original carry flag is rotated into bit 7. The rotated result is stored in the Accumulator and the contents of the Data Memory remain unchanged.
ACC.i ← [m].(i+1); (i=0~6)
ACC.7 ← C
C ← [m].0
C
SBC A,[m]
Description
Operation
Affected flag(s)
Subtract Data Memory from ACC with Carry
The contents of the specified Data Memory and the complement of the carry flag are
subtracted from the Accumulator. The result is stored in the Accumulator. Note that if the result of subtraction is negative, the C flag will be cleared to 0, otherwise if the result is
positive or zero, the C flag will be set to 1.
ACC ← ACC − [m] − C
OV, Z, AC, C
SBCM A,[m]
Description
Operation
Affected flag(s)
Subtract Data Memory from ACC with Carry and result in Data Memory
The contents of the specified Data Memory and the complement of the carry flag are subtracted from the Accumulator. The result is stored in the Data Memory. Note that if the result of subtraction is negative, the C flag will be cleared to 0, otherwise if the result is positive or zero, the C flag will be set to 1.
[m] ← ACC − [m] − C
OV, Z, AC, C
SDZ [m]
Description
Operation
Affected flag(s)
Skip if decrement Data Memory is 0
The contents of the specified Data Memory are first decremented by 1. If the result is 0 the following instruction is skipped. As this requires the insertion of a dummy instruction while the next instruction is fetched, it is a two cycle instruction. If the result is not 0 the program proceeds with the following instruction.
[m] ← [m] − 1
Skip if [m]=0
None
Rev. 1.30
194
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
SDZA [m]
Description
Operation
Affected flag(s)
Skip if decrement Data Memory is zero with result in ACC
The contents of the specified Data Memory are first decremented by 1. If the result is 0, the following instruction is skipped. The result is stored in the Accumulator but the specified Data Memory contents remain unchanged. As this requires the insertion of a dummy
instruction while the next instruction is fetched, it is a two cycle instruction. If the result is not 0,
the program proceeds with the following instruction.
ACC ← [m] − 1
Skip if ACC=0
None
SET [m]
Description
Operation
Affected flag(s)
Set Data Memory
Each bit of the specified Data Memory is set to 1.
[m] ← FFH
None
SET [m].i
Description
Operation
Affected flag(s)
Set bit of Data Memory
Bit i of the specified Data Memory is set to 1.
[m].i ← 1
None
SIZ [m]
Description
Operation
Affected flag(s)
Skip if increment Data Memory is 0
The contents of the specified Data Memory are first incremented by 1. If the result is 0, the
following instruction is skipped. As this requires the insertion of a dummy instruction while the next instruction is fetched, it is a two cycle instruction. If the result is not 0 the program
proceeds with the following instruction.
[m] ← [m] + 1
Skip if [m]=0
None
SIZA [m]
Description
Operation
Affected flag(s)
Skip if increment Data Memory is zero with result in ACC
The contents of the specified Data Memory are first incremented by 1. If the result is 0, the following instruction is skipped. The result is stored in the Accumulator but the specified
Data Memory contents remain unchanged. As this requires the insertion of a dummy
instruction while the next instruction is fetched, it is a two cycle instruction. If the result is not
0 the program proceeds with the following instruction.
ACC ← [m] + 1
Skip if ACC=0
None
SNZ [m].i
Description
Operation
Affected flag(s)
Skip if bit i of Data Memory is not 0
If bit i of the specified Data Memory is not 0, the following instruction is skipped. As this
requires the insertion of a dummy instruction while the next instruction is fetched, it is a two cycle instruction. If the result is 0 the program proceeds with the following instruction.
Skip if [m].i ≠ 0
None
SUB A,[m]
Description
Operation
Affected flag(s)
Subtract Data Memory from ACC
The specified Data Memory is subtracted from the contents of the Accumulator. The result is stored in the Accumulator. Note that if the result of subtraction is negative, the C flag will be cleared to 0, otherwise if the result is positive or zero, the C flag will be set to 1.
ACC ← ACC − [m]
OV, Z, AC, C
Rev. 1.30
195
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
SUBM A,[m]
Description
Operation
Affected flag(s)
Subtract Data Memory from ACC with result in Data Memory
The specified Data Memory is subtracted from the contents of the Accumulator. The result is stored in the Data Memory. Note that if the result of subtraction is negative, the C flag will be cleared to 0, otherwise if the result is positive or zero, the C flag will be set to 1.
[m] ← ACC − [m]
OV, Z, AC, C
SUB A,x
Description
Operation
Affected flag(s)
Subtract immediate data from ACC
The immediate data specified by the code is subtracted from the contents of the Accumulator. The result is stored in the Accumulator. Note that if the result of subtraction is negative, the C flag will be cleared to 0, otherwise if the result is positive or zero, the C flag will be set to 1.
ACC ← ACC − x
OV, Z, AC, C
SWAP [m]
Description
Operation
Affected flag(s)
Swap nibbles of Data Memory
The low-order and high-order nibbles of the specified Data Memory are interchanged.
[m].3~[m].0 ↔ [m].7~[m].4
None
SWAPA [m]
Description
Operation
Affected flag(s)
Swap nibbles of Data Memory with result in ACC
The low-order and high-order nibbles of the specified Data Memory are interchanged. The result is stored in the Accumulator. The contents of the Data Memory remain unchanged.
ACC.3~ACC.0 ← [m].7~[m].4
ACC.7~ACC.4 ← [m].3~[m].0
None
SZ [m]
Description
Operation
Affected flag(s)
Skip if Data Memory is 0
If the contents of the specified Data Memory is 0, the following instruction is skipped. As this requires the insertion of a dummy instruction while the next instruction is fetched, it is a two cycle instruction. If the result is not 0 the program proceeds with the following instruction.
Skip if [m]=0
None
SZA [m]
Description
Operation
Affected flag(s)
Skip if Data Memory is 0 with data movement to ACC
The contents of the specified Data Memory are copied to the Accumulator. If the value is zero, the following instruction is skipped. As this requires the insertion of a dummy instruction while the next instruction is fetched, it is a two cycle instruction. If the result is not 0 the program proceeds with the following instruction.
ACC ← [m]
Skip if [m]=0
None
SZ [m].i
Description
Operation
Affected flag(s)
Skip if bit i of Data Memory is 0
If bit i of the specified Data Memory is 0, the following instruction is skipped. As this requires
the insertion of a dummy instruction while the next instruction is fetched, it is a two cycle
instruction. If the result is not 0, the program proceeds with the following instruction.
Skip if [m].i=0
None
Rev. 1.30
196
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
TABRDC [m]
Description
Operation
Affected flag(s)
Read table (current page) to TBLH and Data Memory
The low byte of the program code (current page) addressed by the table pointer (TBLP) is moved to the specified Data Memory and the high byte moved to TBLH.
[m] ← program code (low byte)
TBLH ← program code (high byte)
None
TABRDL [m]
Description
Operation
Affected flag(s)
Read table (last page) to TBLH and Data Memory
The low byte of the program code (last page) addressed by the table pointer (TBLP) is moved to the specified Data Memory and the high byte moved to TBLH.
[m] ← program code (low byte)
TBLH ← program code (high byte)
None
XOR A,[m]
Description
Operation
Affected flag(s)
Logical XOR Data Memory to ACC
Data in the Accumulator and the specified Data Memory perform a bitwise logical XOR operation. The result is stored in the Accumulator.
ACC ← ACC ″XOR″ [m]
Z
XORM A,[m]
Description
Operation
Affected flag(s)
Logical XOR ACC to Data Memory
Data in the specified Data Memory and the Accumulator perform a bitwise logical XOR operation. The result is stored in the Data Memory.
[m] ← ACC ″XOR″ [m]
Z
XOR A,x
Description
Operation
Affected flag(s)
Logical XOR immediate data to ACC
Data in the Accumulator and the specified immediate data perform a bitwise logical XOR operation. The result is stored in the Accumulator.
ACC ← ACC ″XOR″ x
Z
Rev. 1.30
197
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
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. 1.30
198
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
16-pin DIP (300mil) Outline Dimensions
Fig1. Full Lead Packages
Fig1. 1/2 Lead Packages
fig 1
Symbol
Nom.
Max.
0.800
A
0.780
0.790
B
0.240
0.250
0.280
C
0.115
0.130
0.195
D
0.115
0.130
0.150
E
0.014
0.018
0.022
F
0.045
0.060
0.070
G
—
0.100 BSC
—
H
0.300
0.310
0.325
I
—
—
0.430
Symbol
Rev. 1.30
Dimensions in inch
Min.
Dimensions in mm
Min.
Nom.
Max.
A
19.81
20.07
20.32
B
6.10
6.35
7.11
4.95
C
2.92
3.30
D
2.92
3.30
3.81
E
0.36
0.46
0.56
1.78
F
1.14
1.52
G
—
2.54 BSC
—
H
7.62
7.87
8.26
I
—
—
10.92
199
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
fig 2
Symbol
Dimensions in inch
Min.
Nom.
Max.
A
0.745
0.765
0.785
B
0.275
0.285
0.295
C
0.120
0.135
0.150
D
0.110
0.130
0.150
E
0.014
0.018
0.022
F
0.045
0.050
0.060
G
—
0.100 BSC
—
H
0.300
0.310
0.325
I
—
—
0.430
Symbol
Dimensions in mm
Min.
Nom.
Max.
A
18.92
19.43
19.94
B
6.99
7.24
7.49
C
3.05
3.43
3.81
D
2.79
3.30
3.81
E
0.36
0.46
0.56
F
1.14
1.27
1.52
G
—
2.54 BSC
—
H
7.62
7.87
8.26
I
—
—
10.92
fig 2
Symbol
Nom.
Max.
A
0.735
0.755
0.775
B
0.240
0.250
0.280
C
0.115
0.130
0.195
D
0.115
0.130
0.150
E
0.014
0.018
0.022
F
0.045
0.060
0.070
G
—
0.100 BSC
—
H
0.300
0.310
0.325
I
—
—
0.430
Symbol
Rev. 1.30
Dimensions in inch
Min.
Dimensions in mm
Min.
Nom.
Max.
A
18.67
19.18
19.69
B
6.10
6.35
7.11
C
2.92
3.30
4.95
D
2.92
3.30
3.81
E
0.36
0.46
0.56
F
1.14
1.52
1.78
G
—
2.54 BSC
—
H
7.62
7.87
8.26
I
—
—
10.92
200
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
16-pin NSOP (150mil) Outline Dimensions
Symbol
A
Dimensions in inch
Min.
Nom.
Max.
—
0.236 BSC
—
B
—
0.154 BSC
—
C
0.012
—
0.020
C'
—
0.390 BSC
—
D
—
—
0.069
E
—
0.050 BSC
—
F
0.004
—
0.010
G
0.016
—
0.050
H
0.004
—
0.010
α
0°
―
8°
Symbol
Rev. 1.30
Dimensions in mm
Min.
Nom.
Max.
A
—
6.00 BSC
—
B
—
3.90 BSC
—
C
0.31
—
0.51
C'
—
9.90 BSC
—
D
—
—
1.75
E
—
1.27 BSC
—
F
0.10
—
0.25
G
0.40
—
1.27
H
0.10
—
0.25
α
0°
―
8°
201
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
16-pin SSOP (150mil) Outline Dimensions
Symbol
Dimensions in inch
Min.
Nom.
Max.
—
A
—
0.236 BSC
B
—
0.154 BSC
—
C
0.008
—
0.012
C’
—
0.193 BSC
—
D
—
—
0.069
E
—
0.025 BSC
—
0.010
F
0.004
—
G
0.016
—
0.050
H
0.004
—
0.010
α
0°
—
8°
Symbol
Rev. 1.30
Dimensions in mm
Min.
Nom.
Max.
—
A
—
6.000 BSC
B
—
3.900 BSC
—
C
0.20
—
0.30
C’
—
4.900 BSC
—
D
—
—
1.75
E
—
0.635 BSC
—
F
0.10
—
0.25
G
0.41
—
1.27
H
0.10
—
0.25
α
0°
—
8°
202
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
20-pin DIP (300mil) Outline Dimensions
Fig1. Full Lead Packages Fig2. 1/2 Lead Packages
See Fig1
Symbol
Min.
Nom.
Max.
A
0.980
1.030
1.060
B
0.240
0.250
0.280
C
0.115
0.130
0.195
D
0.115
0.130
0.150
E
0.014
0.018
0.022
0.070
F
0.045
0.060
G
—
0.100 BSC
—
H
0.300
0.310
0.325
I
—
—
0.430
Symbol
Rev. 1.30
Dimensions in inch
Dimensions in mm
Min.
Nom.
Max.
26.92
A
24.89
26.16
B
6.10
6.35
7.11
C
2.92
3.30
4.95
D
2.92
3.30
3.81
E
0.36
0.46
0.56
F
1.14
1.52
1.78
G
—
2.54 BSC
—
H
7.62
7.87
8.26
I
—
—
10.92
203
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
See Fig 2
Symbol
Min.
Nom.
Max.
A
0.945
0.965
0.985
B
0.275
0.285
0.295
C
0.120
0.135
0.150
D
0.110
0.130
0.150
E
0.014
0.018
0.022
F
0.045
0.050
0.060
G
—
0.100 BSC
—
H
0.300
0.310
0.325
I
—
—
0.430
Symbol
Rev. 1.30
Dimensions in inch
Dimensions in mm
Min.
Nom.
Max.
A
24.00
24.51
25.02
B
6.99
7.24
7.49
C
3.05
3.43
3.81
D
2.79
3.30
3.81
E
0.36
0.46
0.56
F
1.14
1.27
1.52
G
—
2.54 BSC
—
H
7.62
7.87
8.26
I
—
—
10.92
204
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
20-pin SOP (300mil) Outline Dimensions
Symbol
Dimensions in inch
Min.
Nom.
Max.
A
—
0.406 BSC
—
B
—
0.295 BSC
—
0.020
C
0.012
—
C’
—
0.504 BSC
—
D
—
—
0.104
E
—
0.050 BSC
—
F
0.004
—
0.012
G
0.016
—
0.050
H
0.008
—
0.013
α
0°
—
8°
Symbol
Rev. 1.30
Dimensions in mm
Min.
Nom.
Max.
A
—
10.30 BSC
—
B
—
7.50 BSC
—
C
0.31
—
0.51
C’
—
12.80 BSC
—
D
—
—
2.65
E
—
1.27 BSC
—
F
0.10
—
0.30
G
0.40
—
1.27
H
0.20
—
0.33
α
0°
—
8°
205
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
20-pin SSOP (150mil) Outline Dimensions
Symbol
Dimensions in inch
Min.
Nom.
Max.
A
—
0.236 BSC
—
B
—
0.155 BSC
—
C
0.008
—
0.012
C’
—
0.341 BSC
—
D
—
—
0.069
E
—
0.025 BSC
—
F
0.004
—
0.0098
G
0.016
—
0.05
H
0.004
—
0.01
α
0°
—
8°
Symbol
Rev. 1.30
Dimensions in mm
Min.
Nom.
Max.
A
—
6.000 BSC
—
B
—
3.900 BSC
—
C
0.20
—
0.30
C’
—
8.660 BSC
—
D
—
—
1.75
E
—
0.635 BSC
—
F
0.10
—
0.25
G
0.41
—
1.27
H
0.10
—
0.25
α
0°
—
8°
206
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
24-pin SKDIP (300mil) Outline Dimensions
Fig1. Full Lead Packages
Fig2. 1/2 Lead Packages
See Fig1
A
Min.
1.230
Dimensions in inch
Nom.
1.250
Max.
1.280
Symbol
B
0.240
0.250
0.280
C
0.115
0.130
0.195
D
0.115
0.130
0.150
E
0.014
0.018
0.022
F
0.045
0.060
0.070
G
—
0.100 BSC
—
H
0.300
0.310
0.325
I
—
—
0.430
A
Min.
31.24
Dimensions in mm
Nom.
31.75
Max.
32.51
B
6.10
6.35
7.11
C
2.92
3.30
4.95
D
2.92
3.30
3.81
E
0.36
0.46
0.56
Symbol
Rev. 1.30
F
1.14
1.52
1.78
G
—
2.54 BSC
—
H
7.62
7.87
8.26
I
—
—
10.92
207
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
See Fig2
A
Min.
1.160
Dimensions in inch
Nom.
1.185
Max.
1.195
Symbol
B
0.240
0.250
0.280
C
0.115
0.130
0.195
D
0.115
0.130
0.150
E
0.014
0.018
0.022
0.070
F
0.045
0.060
G
—
0.100 BSC
—
H
0.300
0.310
0.325
I
—
—
0.430
Symbol
Dimensions in mm
Min.
Nom.
Max.
30.35
A
29.46
30.10
B
6.10
6.35
7.11
C
2.92
3.30
4.95
D
2.92
3.30
3.81
E
0.36
0.46
0.56
F
1.14
1.52
1.78
G
—
2.54 BSC
—
H
7.62
7.87
8.26
I
—
—
10.92
A
Min.
1.145
Dimensions in inch
Nom.
1.165
Max.
1.185
See fig20
Symbol
B
0.275
0.285
0.295
C
0.120
0.135
0.150
D
0.110
0.130
0.150
E
0.014
0.018
0.022
0.060
F
0.045
0.050
G
—
0.100 BSC
—
H
0.300
0.310
0.325
I
—
—
0.430
A
Min.
29.08
Dimensions in mm
Nom.
29.59
Max.
30.10
Symbol
Rev. 1.30
B
6.99
7.24
7.49
C
3.05
3.43
3.81
D
2.79
3.30
3.81
E
0.36
0.46
0.56
1.52
F
1.14
1.27
G
—
2.54 BSC
—
H
7.62
7.87
8.26
I
—
—
10.92
208
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
24-pin SOP (300mil) Outline Dimensions
Symbol
A
Dimensions in inch
Min.
Nom.
Max.
—
0.406 BSC
—
B
—
0.295 BSC
—
C
0.012
—
0.020
C’
—
0.606 BSC
—
D
—
—
0.104
E
—
0.050 BSC
—
F
0.004
—
0.012
G
0.016
—
0.050
H
0.008
—
0.013
α
0°
—
8°
Symbol
Rev. 1.30
Dimensions in mm
Min.
Nom.
Max.
A
—
10.30 BSC
—
B
—
7.50 BSC
—
C
0.31
—
0.51
C’
—
15.40 BSC
—
D
—
—
2.65
E
—
1.27 BSC
—
F
0.10
—
0.30
G
0.40
—
1.27
H
0.20
—
0.33
α
0°
―
8°
209
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
24-pin SSOP(150mil) Outline Dimensions
Symbol
Dimensions in inch
Min.
Nom.
Max.
—
A
—
0.236 BSC
B
—
0.154 BSC
—
C
0.008
—
0.012
C’
—
0.341 BSC
—
D
—
—
0.069
E
—
0.025 BSC
—
0.010
F
0.004
—
G
0.016
—
0.050
H
0.004
—
0.010
α
0°
—
8°
Symbol
Rev. 1.30
Dimensions in mm
Min.
Nom.
Max.
—
A
—
6.000 BSC
B
—
3.900 BSC
—
C
0.20
—
0.30
C’
—
8.660 BSC
—
D
—
—
1.75
E
—
0.635 BSC
—
F
0.10
—
0.25
G
0.41
—
1.27
H
0.10
—
0.25
α
0°
—
8°
210
May 20, 2014
HT66F20-1/HT66F30-1/HT68F20-1/HT68F30-1
Enhanced Flash Type 8-Bit MCU with EEPROM
Copyright© 2014 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. 1.30
211
May 20, 2014