HT67F488_489v150.pdf

TinyPowerTM A/D 8-Bit Flash MCU with LCD & EEPROM
HT67F488
HT67F489
Revision: V1.50
Date: ���������������
August 13, 2014
TinyPower
TM
HT67F488/HT67F489
A/D 8-Bit Flash MCU with LCD & EEPROM
Table of Contents
Features............................................................................................................. 6
CPU Features.......................................................................................................................... 6
Peripheral Features.................................................................................................................. 6
General Description.......................................................................................... 7
Selection Table.................................................................................................. 8
Block Diagram................................................................................................... 8
Pin Assignment................................................................................................. 9
Pin Description............................................................................................... 10
Absolute Maximum Ratings........................................................................... 13
D.C. Characteristics........................................................................................ 13
A.C. Characteristics........................................................................................ 16
A/D Converter Electrical Characteristics...................................................... 16
LVD & LVR Electrical Characteristics........................................................... 17
Power on Reset Characteristics.................................................................... 17
System Architecture....................................................................................... 18
Clocking and Pipelining.......................................................................................................... 18
Program Counter.................................................................................................................... 19
Stack...................................................................................................................................... 20
Arithmetic and Logic Unit – ALU............................................................................................ 20
Flash Program Memory.................................................................................. 21
Structure................................................................................................................................. 21
Special Vectors...................................................................................................................... 21
Look-up Table......................................................................................................................... 22
Table Program Example......................................................................................................... 22
In Circuit Programming – ICP................................................................................................ 23
On-Chip Debug Support – OCDS.......................................................................................... 24
RAM Data Memory.......................................................................................... 25
Structure................................................................................................................................. 25
General Purpose Data Memory ............................................................................................ 25
Special Purpose Data Memory ............................................................................................. 26
Special Function Register Description......................................................... 27
Indirect Addressing Register – IAR0, IAR1, IAR2.................................................................. 27
Memory Pointers – MP0, MP1L, MP1H, MP2L, MP2H.......................................................... 27
Accumulator – ACC................................................................................................................ 28
Program Counter Low Register – PCL .................................................................................. 28
Look-up Table Registers – TBLP, TBHP, TBLH ..................................................................... 29
Status Register – STATUS .................................................................................................... 29
Rev. 1.50
2
August 13, 2014
HT67F488/HT67F489
TinyPowerTM A/D 8-Bit Flash MCU with LCD & EEPROM
EEPROM Data Memory................................................................................... 31
EEPROM Data Memory Structure......................................................................................... 31
EEPROM Registers............................................................................................................... 31
Reading Data from the EEPROM.......................................................................................... 33
Writing Data to the EEPROM................................................................................................. 33
Write Protection...................................................................................................................... 33
EEPROM Interrupt................................................................................................................. 33
Programming Considerations................................................................................................. 34
Programming Examples......................................................................................................... 34
Oscillator......................................................................................................... 35
Oscillator Overview ............................................................................................................... 35
System Clock Configurations ................................................................................................ 35
External Crystal/Ceramic Oscillator – HXT............................................................................ 36
Internal RC Oscillator – HIRC ............................................................................................... 36
External 32.768kHz Crystal Oscillator – LXT......................................................................... 37
LXT Oscillator Low Power Function ...................................................................................... 38
Internal 32kHz Oscillator – LIRC ........................................................................................... 38
Operating Modes and System Clocks ......................................................... 39
System Clocks ...................................................................................................................... 39
System Operation Modes ...................................................................................................... 40
Control Register..................................................................................................................... 41
Operating Mode Switching .................................................................................................... 43
Standby Current Considerations ........................................................................................... 47
Wake-up ................................................................................................................................ 47
Watchdog Timer.............................................................................................. 48
Watchdog Timer Clock Source............................................................................................... 48
Watchdog Timer Control Register.......................................................................................... 48
Watchdog Timer Operation.................................................................................................... 49
Reset and Initialisation................................................................................... 50
Reset Functions .................................................................................................................... 50
Reset Initial Conditions ......................................................................................................... 53
Input/Output Ports ......................................................................................... 56
Pull-high Resistors................................................................................................................. 57
Port A Wake-up...................................................................................................................... 57
I/O Port Control Registers...................................................................................................... 57
Pin-shared Functions............................................................................................................. 57
I/O Pin Structures................................................................................................................... 58
Programming Considerations ................................................................................................ 59
Rev. 1.50
3
August 13, 2014
TinyPower
TM
HT67F488/HT67F489
A/D 8-Bit Flash MCU with LCD & EEPROM
Timer Modules – TM....................................................................................... 60
Introduction............................................................................................................................ 60
TM Operation......................................................................................................................... 60
TM Clock Source.................................................................................................................... 61
TM Interrupts.......................................................................................................................... 61
TM External Pins ................................................................................................................... 61
TM Input/Output Pin Control Registers.................................................................................. 61
Programming Considerations................................................................................................. 63
Periodic Type TM – PTM................................................................................. 64
Periodic TM Operation........................................................................................................... 64
Periodic Type TM Register Description.................................................................................. 65
Periodic Type TM Operating Modes....................................................................................... 70
Compact Type TM – CTM............................................................................... 79
Compact TM Operation ......................................................................................................... 79
Compact Type TM Register Description................................................................................ 80
Compact Type TM Operating Modes..................................................................................... 84
Analog to Digital Converter – ADC................................................................ 90
A/D Overview......................................................................................................................... 90
A/D Converter Register Description....................................................................................... 90
A/D Converter Data Registers – ADRL, ADRH...................................................................... 91
A/D Converter Control Registers – ADCR0, ADCR1, ACERL, ACERH................................. 91
A/D Operation ....................................................................................................................... 95
A/D Input Pins........................................................................................................................ 96
Summary of A/D Conversion Steps ....................................................................................... 97
Programming Considerations................................................................................................. 98
A/D Transfer Function............................................................................................................ 98
A/D Programming Example.................................................................................................... 99
LCD Display Memory.................................................................................... 101
LCD Driver Output................................................................................................................ 101
LCD Control Register........................................................................................................... 102
LCD Waveform..................................................................................................................... 106
LED Driver..................................................................................................... 109
LED Driver Operation........................................................................................................... 109
LED Driver Register............................................................................................................. 109
UART Interface...............................................................................................110
UART External Pin Interfacing..............................................................................................110
UART Data Transfer Scheme...............................................................................................111
UART Status and Control Registers.....................................................................................111
Baud Rate Generator............................................................................................................117
UART Setup and Control......................................................................................................118
UART Transmitter................................................................................................................ 120
UART Receiver.................................................................................................................... 121
Managing Receiver Errors................................................................................................... 123
Rev. 1.50
4
August 13, 2014
HT67F488/HT67F489
TinyPowerTM A/D 8-Bit Flash MCU with LCD & EEPROM
UART Module Interrupt Structure......................................................................................... 124
Address Detect Mode........................................................................................................... 125
UART Module Power Down and Wake-up........................................................................... 125
Interrupts....................................................................................................... 127
Interrupt Registers................................................................................................................ 127
Interrupt Operation............................................................................................................... 135
External Interrupt.................................................................................................................. 137
Multi-function Interrupt......................................................................................................... 137
A/D Converter Interrupt........................................................................................................ 137
UART Interrupt..................................................................................................................... 138
Time Base Interrupt.............................................................................................................. 138
EEPROM Interrupt............................................................................................................... 139
LVD Interrupt........................................................................................................................ 140
TM Interrupts ....................................................................................................................... 140
Interrupt Wake-up Function.................................................................................................. 140
Programming Considerations............................................................................................... 141
Low Voltage Detector – LVD........................................................................ 142
LVD Register........................................................................................................................ 142
LVD Operation...................................................................................................................... 143
Configuration Options.................................................................................. 144
Application Circuits...................................................................................... 144
Instruction Set............................................................................................... 145
Instruction............................................................................................................................. 145
Instruction Timing................................................................................................................. 145
Moving and Transferring Data.............................................................................................. 145
Arithmetic Operations........................................................................................................... 145
Logical and Rotate Operations............................................................................................. 146
Branches and Control Transfer............................................................................................ 146
Bit Operations...................................................................................................................... 146
Table Read Operations........................................................................................................ 146
Other Operations.................................................................................................................. 146
Instruction Set Summary............................................................................. 147
Table Conventions................................................................................................................ 147
Instruction Definition.................................................................................... 149
Package Information.................................................................................... 159
44-pin LQFP (10mm×10mm) (FP2.0mm) Outline Dimensions............................................ 160
Rev. 1.50
5
August 13, 2014
TinyPower
TM
HT67F488/HT67F489
A/D 8-Bit Flash MCU with LCD & EEPROM
Features
CPU Features
• Operating Voltage
♦♦
fSYS = 8MHz: 2.2V~5.5V
♦♦
fSYS = 12MHz: 2.7V~5.5V
• Power down and wake-up functions to reduce power consumption
• Oscillators
♦♦
Internal RC – HIRC
♦♦
External Crystal - HXT
♦♦
Internal 32kHz RC – LIRC
♦♦
External 32.768kHz Crystal – LXT
• Fully integrated internal 8MHz oscillator requires no external components
• Multi-mode operation: NORMAL, SLOW, IDLE and SLEEP
• All instructions executed in one or two instruction cycles
• Bit manipulation instruction
• 16-bit Table Read Function
• 63 powerful instructions
• Support dual words instructions for RAM access
• 8-level subroutine nesting
Peripheral Features
• Flash Program Memory: 4K×16 ~ 8K×16
• RAM Data Memory: 256×8
• EEPROM Memory: 64×8 (only for HT67F489)
• Watchdog Timer function
• 42 bidirectional I/O lines
♦♦
Inlcude LCD/LED driving output
• 4 pin-shared external interrupts
• Multiple Timer Module for time measure, input capture, compare match output, PWM output or
single pulse output functions
• Dual Time-Base functions for generation of fixed time interrupt signals
• 10-channel 12-bit resolution A/D converter
• LCD display
♦♦
20SEG × 4COM & 20SEG × 8COM
♦♦
1/3 or 1/4 bias
• LED display: 8SEG × 8COM
• Low Voltage Reset function
• Low Voltage Detect function
• Package type: 44-pin LQFP
Rev. 1.50
6
August 13, 2014
HT67F488/HT67F489
TinyPowerTM A/D 8-Bit Flash MCU with LCD & EEPROM
General Description
The HT67F488/HT67F489 series of devices are Flash Memory A/D type 8-bit high performance
RISC architecture microcontrollers, designed especially for applications that interface directly to
analog signals, such as those from sensors. Offering users the convenience of Flash Memory multiprogramming features, these devices also include a wide range of functions and features. Other
memory includes an area of RAM Data Memory as well as an area of EEPROM memory (only for
HT67F489) for storage of non-volatile data such as serial numbers, calibration data etc.
Analog features include a multi-channel 12-bit A/D converter function. Multiple and extremely
flexible Timer Modules provide timing, pulse generation and PWM generation functions. 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 HIRC, HXT, LXT 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 minimize power
consumption.
The UART module is contained in these devices. It can support the applications such as data
communication networks between microcontrollers, low-cost data links between PCs and peripheral
devices, portable and battery operated device communication, etc.
The inclusion of both LCD and LED driver functions allows for easy and cost effective solutions in
applications that require interface to these display types.
The inclusion of flexible I/O programming features, Time-Base functions along with many other
features enhance the versatility of these devices to suit a wide range of A/D application possibilities
such as sensor signal processing, chargers, motor driving, industrial control, consumer products,
subsystem controllers, etc.
Rev. 1.50
7
August 13, 2014
TinyPower
TM
HT67F488/HT67F489
A/D 8-Bit Flash MCU with LCD & EEPROM
Selection Table
Most features are common to all devices, the main feature distinguishing them are Memory capacity
and whether EEPROM or not. The following table summarises the main features of each device.
Part No.
Program
Memory
Data
Memory
Data
EEPROM
I/O
Ext.
Interrupt
A/D
LCD Driver
HT67F488
4K×16
256×8
—
42
4
12-bit×10
20×4, 20×8
HT67F489
8K×16
256×8
64×8
42
4
12-bit×10
20×4, 20×8
Part No.
LED Driver
Timer Module
Time Base
UART
Stack
Package
HT67F488
8x8
10-bit CTM×3
10-bit PTM×1
2
√
8
44LQFP
HT67F489
8x8
10-bit CTM×3
10-bit PTM×1
2
√
8
44LQFP
Block Diagram
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8
August 13, 2014
HT67F488/HT67F489
TinyPowerTM A/D 8-Bit Flash MCU with LCD & EEPROM
Pin Assignment
P
P
P
P C
P C
P C
P C
P C
P C
P F 4 /S
P F 5 /S
D 7 /S
C 0 /S
C 1 /S
2 /S E
3 /S E
4 /S E
5 /S E
6 /S E
7 /S E
E G 1
E G 1
E G
E G
E G
G 1
G 1
G 1
G 1
G 1
G 1
6 /R
7 /T
X
X
0
1
2
3
4
5
6 /S E G 1 8 /IN T
1 9 /IN T 1 /T P 0 _
2 /T C K 0 /IC P D
/T P 0 _ 0 /IC P C
V D D & A V D
V S S & A V S
P A 1 /O S C
P A 3 /O S C
P A
P A 4 /X T
P A 5 /X T
4 4 4 3 4 2 4 1 4 0 3 9 3 8 3 7 3 6 3 5 3 4
D
0
K
A
7
8
9
P F
P F 7 /S E G
P A 0 /IN T
P A 2 /IN T 3
1
1
2
3 2
3
3 1
4
3 0
5
S
7
2
6
1
2
2 9
6
1
P D
P D
P D
P D
P D
P D
P D
P E
P E
P E
P E
3 3
2 8
2 7
8
2 6
9
2 5
1 0
1 1
2 4
1 2 1 3 1 4 1 5 1 6 1 7 1 8 1 9 2 0 2 1 2 2
2 3
6 /S
5 /S
4 /S
3 /S
2 /S
1 /S
0 /S
0 /C
1 /C
2 /C
3 /C
E G 6
E G 5
E G 4
E G 3
E G 2
E G 1
E G 0
O M 0
O M 1
O M 2
O M 3
P B 0
P B 1
P B 2
P B 3
P E 4
P E 5
P E 6
P B 4
P E 7
P B 5
P A 7
/A
/A
/A
/A
/A
/A
/A
/A
/A
/A
N 0
N 1
N 2
N 3
N 4
N 5
N 6
N 7
N 8
N 9
/T
/T
/T
/T
/C
/C
/C
/V
/C
C K
P 3
P 2
P 1
O M
O M
O M
R E
O M
3
F
4 /T C K 1
5 /T C K 2
6
7
P
P
P
P C
P C
P C
P C
P C
P C
P F 4 /S
P F 5 /S
D 7 /S
C 0 /S
C 1 /S
2 /S E
3 /S E
4 /S E
5 /S E
6 /S E
7 /S E
E G 1
E G 1
E G
E G
E G
G 1
G 1
G 1
G 1
G 1
G 1
6 /R
7 /T
X
X
0
1
2
3
4
5
4 4 4 3 4 2 4 1 4 0 3 9 3 8 3 7 3 6 3 5 3 4
0
A
D
7
8
9
P F 6 /S E G 1 8 /IN T
P F 7 /S E G 1 9 /IN T 1 /T P 0 _
P A 0 /IN T 2 /T C K 0 /O C D S D A /IC P D
P A 2 /IN T 3 /T P 0 _ 0 /O C D S C K /IC P C
V D D & A V D
V S S & A V S
P A 1 /O S C
P A 3 /O S C
P A
P A 4 /X T
P A 5 /X T
1
1
2
3 2
3
3 1
K
4
3 0
5
S
6
1
1
2
2 9
6
2
3 3
7
2 8
2 7
8
2 6
9
1 0
1 1
2 5
2 4
1 2 1 3 1 4 1 5 1 6 1 7 1 8 1 9 2 0 2 1 2 2
2 3
P D
P D
P D
P D
P D
P D
P D
P E
P E
P E
P E
6 /S
5 /S
4 /S
3 /S
2 /S
1 /S
0 /S
0 /C
1 /C
2 /C
3 /C
E G
E G
E G
E G
E G
E G
E G
6
5
4
3
2
1
0
O M 0
O M 1
O M 2
O M 3
P B 0
P B 1
P B 2
P B 3
P E 4
P E 5
P E 6
P B 4
P E 7
P B 5
P A 7
/A
/A
/A
/A
/A
/A
/A
/A
/A
/A
N 0
N 1
N 2
N 3
N 4
N 5
N 6
N 7
N 8
N 9
/T
/T
/T
/T
/C
/C
/C
/V
/C
C K
P 3
P 2
P 1
O M
O M
O M
R E
O M
3
F
9
4 /T C K 1
5 /T C K 2
6
7
Rev. 1.50
August 13, 2014
TinyPower
TM
HT67F488/HT67F489
A/D 8-Bit Flash MCU with LCD & EEPROM
Pin Description
Pin Name
PA0/INT2/TCK0/
OCDSDA/ICPDA
PA1/OSC2
PA3/OSC1
PA6, PA7
PA2/INT3/TP0_0/
OCDSCK/ICPCK
PA4/XT1
PA5/XT2
PB0/AN0/TCK3
PB1/AN1/TP3
PB2/AN2/TP2
PB3/AN3/TP1
PB4/AN7/VREF
PB5/AN9
PC0/SEG8
PC1/SEG9
Rev. 1.50
Function
OPT
I/T
O/T
Description
PA0
PAPU
PAWU
ST
CMOS
INT2
—
ST
—
External Interrupt 2
TCK0
—
ST
—
TM0 input
OCDSDA
—
ST
CMOS OCDS Address/Data, for EV chip only.
General purpose I/O. Register enabled pull-high and
wake-up.
ICPDA
—
ST
CMOS ICP Address/Data
PA1, PA3,
PA6, PA7
PAPU
PAWU
ST
CMOS
OSC1
OSC
HXT
—
High frequency crystal pin
OSC2
OSC
HXT
—
High frequency crystal pin
PA2
PAPU
PAWU
ST
CMOS
—
General purpose I/O. Register enabled pull-high and
wake-up.
General purpose I/O. Register enabled pull-high and
wake-up.
INT3
—
ST
TP0_0
TMPC
ST
External Interrupt 3
OCDSCK
—
ST
—
OCDS Clock pin, for EV chip only.
ICPCK
—
ST
—
ICP Clock pin
PA4
PAPU
PAWU
ST
CMOS
XT1
FSUBC
LXT
—
PA5
PAPU
PAWU
ST
CMOS
XT2
FSUBC
—
LXT
CMOS TM0 I/O
General purpose I/O. Register enabled pull-high and
wake-up.
Low frequency crystal pin
General purpose I/O. Register enabled pull-high and
wake-up.
Low frequency crystal pin
PB0
PBPU
ST
AN0
ACERL
AN
—
A/D channel 0
TCK3
—
ST
—
TM3 input
PB1
PBPU
ST
AN1
ACERL
AN
CMOS General purpose I/O. Register enabled pull-high.
CMOS General purpose I/O. Register enabled pull-high.
—
A/D channel 1
TP3
TMPC
ST
CMOS TM3 I/O
PB2
PBPU
ST
CMOS General purpose I/O. Register enabled pull-high.
AN2
ACERL
AN
TP2
TMPC
ST
CMOS TM2 I/O
CMOS General purpose I/O. Register enabled pull-high.
PB3
PBPU
ST
AN3
ACERL
AN
—
A/D channel 2
—
A/D channel 3
TP1
TMPC
ST
CMOS TM1 I/O
PB4
PBPU
ST
CMOS General purpose I/O. Register enabled pull-high.
AN7
ACERL
AN
VREF
ADCR1
AN
PB5
PBPU
ST
AN9
ACERH
AN
PC0
PCPU
ST
CMOS General purpose I/O. Register enabled pull-high.
SEG8
SEGCR1
—
CMOS LCD segment output
PC1
PCPU
ST
CMOS General purpose I/O. Register enabled pull-high.
SEG9
SEGCR1
—
CMOS LCD segment output
—
A/D channel 7
—
ADC reference voltage input pin
CMOS General purpose I/O. Register enabled pull-high.
—
A/D channel 9
10
August 13, 2014
HT67F488/HT67F489
TinyPowerTM A/D 8-Bit Flash MCU with LCD & EEPROM
Pin Name
PC2/SEG10
PC3/SEG11
PC4/SEG12
PC5/SEG13
PC6/SEG14
PC7/SEG15
PD0/SEG0
PD1/SEG1
PD2/SEG2
PD3/SEG3
PD4/SEG4
PD5/SEG5
PD6/SEG6
PD7/SEG7
PE0/COM0
PE1/COM1
PE2/COM2
PE3/COM3
PE4/AN4/COM4/
TCK1
Rev. 1.50
Function
OPT
I/T
O/T
Description
PC2
PCPU
ST
CMOS General purpose I/O. Register enabled pull-high.
SEG10
SEGCR1
—
CMOS LCD segment output
PC3
PCPU
ST
CMOS General purpose I/O. Register enabled pull-high.
SEG11
SEGCR1
—
CMOS LCD segment output
PC4
PCPU
ST
CMOS General purpose I/O. Register enabled pull-high.
SEG12
SEGCR1
—
CMOS LCD segment output
PC5
PCPU
ST
CMOS General purpose I/O. Register enabled pull-high.
SEG13
SEGCR1
—
CMOS LCD segment output
PC6
PCPU
ST
CMOS General purpose I/O. Register enabled pull-high.
SEG14
SEGCR1
—
CMOS LCD segment output
PC7
PCPU
ST
CMOS General purpose I/O. Register enabled pull-high.
SEG15
SEGCR1
—
CMOS LCD segment output
PD0
PDPU
ST
CMOS General purpose I/O. Register enabled pull-high.
SEG0
SEGCR0
—
CMOS LCD segment output
PD1
PDPU
ST
CMOS General purpose I/O. Register enabled pull-high.
SEG1
SEGCR0
—
CMOS LCD segment output
PD2
PDPU
ST
CMOS General purpose I/O. Register enabled pull-high.
SEG2
SEGCR0
—
CMOS LCD segment output
PD3
PDPU
ST
CMOS General purpose I/O. Register enabled pull-high.
SEG3
SEGCR0
—
CMOS LCD segment output
PD4
PDPU
ST
CMOS General purpose I/O. Register enabled pull-high.
SEG4
SEGCR0
—
CMOS LCD segment output
PD5
PDPU
ST
CMOS General purpose I/O. Register enabled pull-high.
SEG5
SEGCR0
—
CMOS LCD segment output
PD6
PDPU
ST
CMOS General purpose I/O. Register enabled pull-high.
SEG6
SEGCR0
—
CMOS LCD segment output
PD7
PDPU
ST
CMOS General purpose I/O. Register enabled pull-high.
SEG7
SEGCR0
—
CMOS LCD segment output
PE0
PEPU
ST
CMOS General purpose I/O. Register enabled pull-high.
COM0
LCDC0
—
CMOS LCD common output
PE1
PEPU
ST
CMOS General purpose I/O. Register enabled pull-high.
COM1
LCDC0
—
CMOS LCD common output
PE2
PEPU
ST
CMOS General purpose I/O. Register enabled pull-high.
COM2
LCDC0
—
CMOS LCD common output
PE3
PEPU
ST
CMOS General purpose I/O. Register enabled pull-high.
COM3
LCDC0
—
CMOS LCD common output
PE4
PEPU
ST
CMOS General purpose I/O. Register enabled pull-high.
AN4
ACERL
AN
COM4
LCDC0
—
TCK1
—
ST
—
A/D channel 4
CMOS LCD common output
—
TM1 input
11
August 13, 2014
TinyPower
TM
Pin Name
PE5/AN5/COM5/
TCK2
PE6/AN6/COM6
PE7/AN8/COM7
PF4/SEG16/RX
PF5/SEG17/TX
PF6/SEG18/INT0
PF7/SEG19/
INT1/TP0_1
Function
OPT
I/T
PE5
PEPU
ST
AN5
ACERL
AN
COM5
LCDC0
—
TCK2
—
ST
HT67F488/HT67F489
A/D 8-Bit Flash MCU with LCD & EEPROM
O/T
Description
CMOS General purpose I/O. Register enabled pull-high.
—
A/D channel 5
CMOS LCD common output
—
TM2 input
PE6
PEPU
ST
AN6
ACERL
AN
CMOS General purpose I/O. Register enabled pull-high.
COM6
LCDC0
—
CMOS LCD common output
PE7
PEPU
ST
CMOS General purpose I/O. Register enabled pull-high.
AN8
ACERH
AN
COM7
LCDC0
—
CMOS LCD common output
—
A/D channel 6
—
A/D channel 8
PF4
PFPU
ST
CMOS General purpose I/O. Register enabled pull-high.
SEG16
SEGCR2
—
CMOS LCD segment output
RX
—
ST
PF5
PFPU
ST
CMOS General purpose I/O. Register enabled pull-high.
SEG17
SEGCR2
—
CMOS LCD segment output
—
External UART RX serial data input pin
TX
—
—
CMOS External UART TX serial data output pin
PF6
PFPU
ST
CMOS General purpose I/O. Register enabled pull-high.
SEG18
SEGCR2
—
CMOS LCD segment output
INT0
—
ST
PF7
PFPU
ST
CMOS General purpose I/O. Register enabled pull-high.
SEG19
SEGCR2
—
CMOS LCD segment output
—
External Interrupt 0
INT1
—
ST
TP0_1
TMPC
ST
AVDD
—
PWR
—
ADC Power Supply
VDD
VDD
—
PWR
—
Power Supply
AVSS
AVSS
—
PWR
—
ADC Ground
VSS
VSS
—
PWR
—
Ground
AVDD
Note: I/T: Input type; OP: Optional by register option
PWR: Power; CMOS: CMOS output; LXT: Low frequency crystal oscillator
Rev. 1.50
—
External Interrupt 1
CMOS TM0 I/O
O/T: Output type
ST: Schmitt Trigger input
AN: Analog input pin
12
August 13, 2014
HT67F488/HT67F489
TinyPowerTM A/D 8-Bit Flash MCU with LCD & 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
Ta=25°C
Symbol
VDD
IDD1
Parameter
Operating Voltage (HXT)
Operating Current,
Normal Mode, fSYS=fH,
fSUB=fLXT or fLIRC
Test Conditions
─
3V
5V
3V
5V
3V
5V
3V
IDD2
Operating Current,
Normal Mode, fH=8MHz
5V
3V
5V
3V
5V
3V
5V
3V
5V
IDD3
Operating Current,
Slow Mode, fSYS= fSUB
(LXT, LIRC)
3V
5V
3V
5V
Rev. 1.50
Min.
Typ.
fSYS=4MHz
2.2
─
5.5
V
fSYS=8MHz
2.2
─
5.5
V
fSYS=12MHz
2.7
─
5.5
V
fSYS=16MHz
4.5
─
5.5
V
—
1.6
2.4
mA
—
3.3
5.0
mA
No load, fSYS=fH/2,
ADC off, WDT enable
—
0.9
1.5
mA
—
2.5
3.75
mA
No load, fSYS=fH/4,
ADC off, WDT enable
—
0.7
1.0
mA
—
2.0
3.0
mA
No load, fSYS=fH/8,
ADC off, WDT enable
—
0.6
0.9
mA
—
1.6
2.4
mA
No load, fSYS=fH/16,
ADC off, WDT enable
—
0.5
0.75
mA
—
1.5
2.25
mA
No load, fSYS=fH/32,
ADC off, WDT enable
—
0.49
0.74
mA
—
1.45
2.18
mA
No load, fSYS=fH/64,
ADC off, WDT enable
—
0.47
0.71
mA
—
1.4
2.1
mA
No load, fSYS=LXT,
ADC off, WDT enable,
LXTLP=0, LVR enable
—
45
75
μA
—
90
140
μA
No load, fSYS=LXT,
ADC off, WDT enable,
LXTLP=1, LVR enable
—
40
70
μA
—
85
135
μA
No load, fSYS=LIRC,
ADC off, WDT enable,
LVR enable
—
40
65
μA
—
80
130
μA
VDD
Conditions
No load, fH=8MHz,
ADC off, WDT enable
13
Max. Unit
August 13, 2014
TinyPower
TM
Symbol
Parameter
HT67F488/HT67F489
A/D 8-Bit Flash MCU with LCD & EEPROM
Test Conditions
3V
IIDLE01
IDLE0 Mode Stanby Current
(LXT On)
5V
3V
5V
IIDLE02
IDLE0 Mode Stanby Current
(LIRC On)
3V
5V
3V
IIDLE03
IDLE0 Mode Stanby Current
(LXT On)
5V
3V
IIDLE04
IDLE0 Mode Stanby Current
(LXT On)
5V
3V
IIDLE05
IDLE0 Mode Stanby Current
(LXT On)
5V
3V
IIDLE06
Min.
Typ.
No load, ADC off,
WDT enable, LXTLP=0
—
2
4
μA
—
4
8
μA
No load, ADC off,
WDT enable, LXTLP=1
—
1.5
3.0
μA
—
3.0
6.0
μA
No load, ADC off,
WDT enable
—
1.5
3.0
μA
—
3.0
6.0
μA
No load, ADC off,
WDT enable, LXTLP=1, LCD
enable
(RT=1170kΩ without quick
charge, VLCD=VDD)
—
3
6
μA
—
6
12
μA
No load, ADC off,
WDT enable, LXTLP=1, LCD
enable
(RT=225kΩ without quick
charge, VLCD=VDD)
—
14
28
μA
—
24
48
μA
—
5
10
μA
—
9
18
μA
—
11
22
μA
—
18
36
μA
—
0.5
3.0
mA
—
1.0
6.0
mA
No load, ADC off,
WDT disable
—
0.2
1
μA
—
0.4
2
μA
No load, ADC off,
WDT enable
—
1.5
3.0
μA
—
2.5
5.0
μA
VDD
IDLE0 Mode Stanby Current
(LXT On)
5V
3V
Conditions
No load, ADC off,
WDT enable, LXTLP=1,
LCD enable
(RT=1170kΩ with quick
charge, QCT[2:0]=0,
VLCD=VDD)
No load, ADC off,
WDT enable, LXTLP=1, LCD
enable
(RT=1170kΩ with quick
charge, QCT[2:0]=7,
VLCD=VDD)
IIDLE1
IDLE1 Mode Stanby Current
(LIRC On)
ISLEEP0
SLEEP0 Mode Stanby Current
(LXT or LIRC Off)
3V
ISLEEP1
SLEEP1 Mode Stanby Current
(LXT or LIRC On)
3V
VIL
Input Low Voltage for I/O Ports or
Input Pins
—
—
0
—
0.3VDD
V
VIH
Input High Voltage for I/O Ports
or Input Pins
—
—
0.7VDD
—
VDD
V
Rev. 1.50
5V
5V
5V
No load, ADC off,
WDT enable, fSYS=8MHz on
Max. Unit
14
August 13, 2014
HT67F488/HT67F489
TinyPowerTM A/D 8-Bit Flash MCU with LCD & EEPROM
Symbol
Parameter
Test Conditions
VDD
Conditions
Min.
Typ.
Max. Unit
GPIO (except for PD0~PD7 & PE0~PE7)
IOL
IOH
I/O Port Sink Current
I/O Port Source Current
3V
VOL=0.1VDD
4
8
—
mA
5V
VOL=0.1VDD
10
20
—
mA
3V
VOH=0.9VDD
-2
-4
—
mA
5V
VOH=0.9VDD
-5
-10
—
mA
3V
VOL=0.1VDD
8
16
—
mA
5V
VOL=0.1VDD
20
40
—
mA
3V
VOH=0.9VDD
-2
-4
—
mA
5V
VOH=0.9VDD
-5
-10
—
mA
High Sink I/O for LED driver (PE0~PE7)
IOL
IOH
I/O Port Sink Current
I/O Port Source Current
Adjustable source I/O for LED driver (PD0~PD7)
IOL
I/O Port Sink Current
3V
VOL=0.1VDD
4
8
—
mA
5V
VOL=0.1VDD
10
20
—
mA
VOH= 0.9VDD
(IOHSn[1:0]=00B, n=0~7)
-2
-4
—
mA
VOH= 0.9VDD
(IOHSn[1:0]=01B, n=0~7)
-0.67
-1.33
—
mA
VOH= 0.9VDD
(IOHSn[1:0]=10B, n=0~7)
-0.5
-1
—
mA
VOH= 0.9VDD
(IOHSn[1:0]=11B, n=0~7)
-0.33
-0.66
—
mA
VOH= 0.9VDD
(IOHSn[1:0]=00B, n=0~7)
-5
-10
—
mA
VOH= 0.9VDD
(IOHSn[1:0]=01B, n=0~7)
-1.67
-3.33
—
mA
VOH= 0.9VDD
(IOHSn[1:0]=10B, n=0~7)
-1.25
-2.5
—
mA
VOH= 0.9VDD
(IOHSn[1:0]=11B, n=0~7)
-0.83
-1.67
—
mA
3V
IOH
I/O Port Source Current
5V
3V
—
20
60
100
kΩ
5V
—
10
30
50
kΩ
3V/5V
—
-30
RT
+30
%
Total I/O Port Sink Current
5V
—
80
—
—
mA
Total I/O Port Source Current
5V
—
-80
—
—
mA
RPH
Pull-high Resistance for I/O Ports
RT
LCD total bias resister
ITOL
ITOH
Rev. 1.50
15
August 13, 2014
TinyPower
TM
HT67F488/HT67F489
A/D 8-Bit Flash MCU with LCD & EEPROM
A.C. Characteristics
Ta=25°C
Symbol
fCPU
Parameter
Operating Clock
Test Conditions
Min.
Typ.
Max.
Unit
2.2~5.5
DC
─
4
MHz
2.2~5.5V
DC
─
8
MHz
2.7~5.5V
DC
─
12
MHz
4.5~5.5V
DC
─
16
MHz
—
8
—
MHz
Ta=0°C to 70°C
-2%
8
+2%
MHz
Ta=25°C
-10%
32
+10%
kHz
μs
VDD
Conditions
—
fSYS
System Clock (HIRC)
2.2V~5.5V
fHIRC
System Clock (HIRC)
4.5V~5.5V
fLIRC
System Clock (LIRC)
5V
tTIMER
TCKn Input Pulse Width
—
—
0.3
—
—
tINT
Interrupt Pulse Width
—
—
10
—
—
μs
tEERD
EEPROM Read Time
5V
—
—
2
4
tSYS
tEEWR
EEPROM Write Time
5V
—
—
2
4
ms
—
—
25
50
100
ms
tRSTD
System Reset Delay Time
(Power On Reset, LVR Reset,
WDTC/LVRC S/W Reset)
System Reset Delay Time
(WDT Time-out Reset)
—
—
8.3
16.7
33.3
ms
tSST
System Start-up Timer Period
(Wake-up from HALT)
—
—
fSYS=LXT/HXT
—
1024
—
—
fSYS=HIRC
—
16
—
—
fSYS=LIRC
—
2
—
tSYS
Note: tSYS=1/fSYS
A/D Converter Electrical Characteristics
Ta=25°C
Symbol
Parameter
Test Conditions
VDD
Conditions
Min. Typ.
Max.
Unit
AVDD
A/D Converter Operating Voltage
—
—
2.7
—
5.5
V
VADI
A/D Converter Input Voltage
—
—
0
—
AVDD/VREF
V
VREF
A/D Converter Reference Voltage
—
—
2
—
AVDD
V
VBG
Reference with buffer voltage
—
—
+3%
V
-4
—
+4
LSB
-3% 1.09
DNL
Differential Non-linearity
5V
VREF=AVDD=VDD
tADCK=0.5μs
INL
Integral Non-linearity
5V
VREF=AVDD=VDD
tADCK=0.5μs
-7
—
+7
LSB
IADC
Additional Power Consumption if
A/D Converter is used
3V
No load (tADCK=0.5μs)
—
0.9
1.35
mA
5V
No load (tADCK=0.5μs)
—
1.2
1.8
mA
IBG
Additional Power Consumption if VBG
Reference with Buffer is Used
—
—
—
200
300
μA
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
tBGS
VBG Turn on Stable Time
—
—
—
—
200
μs
Rev. 1.50
12-bit ADC
16
August 13, 2014
HT67F488/HT67F489
TinyPowerTM A/D 8-Bit Flash MCU with LCD & EEPROM
LVD & LVR Electrical Characteristics
Ta=25°C
Symbol
Test Conditions
Parameter
VDD
Conditions
Min. Typ. Max. Unit
VLVR1
LVR Enable, 2.10V option
-5%
2.10
+5%
V
VLVR2
LVR Enable, 2.55V option
-5%
2.55
+5%
V
LVR Enable, 3.15V option
-5%
3.15
+5%
V
VLVR4
LVR Enable, 3.80V option
-5%
3.80
+5%
V
VLVD1
LVDEN=1, VLVD=2.0V
-5%
2.0
+5%
V
VLVD2
LVDEN=1, VLVD=2.2V
-5%
2.2
+5%
V
VLVD3
LVDEN=1, VLVD=2.4V
-5%
2.4
+5%
V
LVDEN=1, VLVD=2.7V
-5%
2.7
+5%
V
LVDEN=1, VLVD=3.0V
-5%
3.0
+5%
V
VLVD6
LVDEN=1, VLVD=3.3V
-5%
3.3
+5%
V
VLVD7
LVDEN=1, VLVD=3.6V
-5%
3.6
+5%
V
LVDEN=1, VLVD=4.0V
-5%
4.0
+5%
V
—
30
45
μA
VLVR3
VLVD4
VLVD5
Low Voltage Reset Voltage
—
Low Voltage Detector Voltage
—
VLVD8
ILVD
Additional Power Consumption
if LVD is used
3V LVD disable → LVD enable
5V (LVR enable)
—
60
90
μA
tLVR
Low Voltage Width to Reset
—
—
120
240
480
μs
tLVD
Low Voltage Width to Interrupt
—
—
20
45
90
μs
tLVDS
LVDO stable time
—
tSRESET
Software Reset Width to Reset
—
For LVR enable, LVD off→on
—
—
—
15
μs
45
90
120
μs
Power on Reset Characteristics
Ta=25°C
Symbol
Test Conditions
Parameter
VDD
Conditions
Min.
Typ. Max.
Unit
VPOR
VDD Start Voltage to Ensure Power-on Reset
—
—
—
—
100
mV
RRVDD
VDD Raising Rate to Ensure Power-on Reset
—
—
0.035
—
—
V/ms
tPOR
Minimum Time for VDD Stays at VPOR to Ensure
Power-on Reset
—
—
1
—
—
ms
Rev. 1.50
17
August 13, 2014
HT67F488/HT67F489
A/D 8-Bit Flash MCU with LCD & EEPROM
TinyPower
TM
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 the
devices suitable for low-cost, high-volume production for controller applications.
Clocking and Pipelining
The main system clock, derived from either a HIRC, HXT, LXT or LIRC oscillator is subdivided
into four internally generated non-overlapping clocks, T1~T4. The Program Counter is incremented
at the beginning of the T1 clock during which time a new instruction is fetched. The remaining
T2~T4 clocks carry out the decoding and execution functions. In this way, one T1~T4 clock
cycle forms one instruction cycle. Although the fetching and execution of instructions takes place
in consecutive instruction cycles, the pipelining structure of the microcontroller ensures that
instructions are effectively executed in one instruction cycle. The exception to this are instructions
where the contents of the Program Counter are changed, such as subroutine calls or jumps, in which
case the instruction will take one more instruction cycle to execute.


   
   
System Clocking and Pipelining
Rev. 1.50
18
August 13, 2014
HT67F488/HT67F489
TinyPowerTM A/D 8-Bit Flash MCU with LCD & EEPROM
For instructions involving branches, such as jump or call instructions, two machine cycles are
required to complete instruction execution. An extra cycle is required as the program takes one
cycle to first obtain the actual jump or call address and then another cycle to actually execute the
branch. The requirement for this extra cycle should be taken into account by programmers in timing
sensitive applications.
  
    
 Instruction Fetching
Program Counter
During program execution, the Program Counter is used to keep track of the address of the next
instruction to be executed. It is automatically incremented by one each time an instruction is ex­
ecuted except for instructions, such as “JMP” or “CALL” that demands a jump to a non-consecutive
Program Memory address. Only the lower 8 bits, known as the Program Counter Low Register, are
directly addressable by the application program.
When executing instructions requiring jumps to non-consecutive addresses such as a jump
instruction, a subroutine call, interrupt or reset, etc., the microcontroller manages program control
by loading the required address into the Program Counter. For conditional skip instructions, once
the condition has been met, the next instruction, which has already been fetched during the present
instruction execution, is discarded and a dummy cycle takes its place while the correct instruction is
obtained.
Device
Program Counter
Program Counter High Byte
PCL Register
HT67F488
PC11~PC8
PCL7~PCL0
HT67F489
PC12~PC8
PCL7~PCL0
Program Counter
The lower byte of the Program Counter, known as the Program Counter Low register or PCL, is
available for program control and is a readable and writeable register. By transferring data directly
into this register, a short program jump can be executed directly. However, as only this low byte
is available for manipulation, the jumps are limited to the present page of memory, that is 256
locations. When such program jumps are executed it should also be noted that a dummy cycle
will be inserted. Manipulating the PCL register may cause program branching, so an extra cycle is
needed to pre-fetch.
Rev. 1.50
19
August 13, 2014
TinyPower
TM
HT67F488/HT67F489
A/D 8-Bit Flash MCU with LCD & EEPROM
Stack
This is a special part of the memory which is used to save the contents of the Program Counter
only. The stack is organized into 8 levels and neither part of the data nor part of the program space,
and is neither readable nor writeable. The activated level is indexed by the Stack Pointer, and is
neither readable nor writeable. At a subroutine call or interrupt acknowledge signal, the contents of
the Program Counter are pushed onto the stack. At the end of a subroutine or an interrupt routine,
signaled by a return instruction, RET or RETI, the Program Counter is restored to its previous value
from the stack. After a device reset, the Stack Pointer will point to the top of the stack.
If the stack is full and an enabled interrupt takes place, the interrupt request flag will be recorded but
the acknowledge signal will be inhibited. When the Stack Pointer is decremented, by RET or RETI,
the interrupt will be serviced. This feature prevents stack overflow allowing the programmer to use
the structure more easily. However, when the stack is full, a CALL subroutine instruction can still
be executed which will result in a stack overflow. Precautions should be taken to avoid such cases
which might cause unpredictable program branching.
If the stack is overflow, the first Program Counter save in the stack will be lost.
P ro g ra m
T o p o f S ta c k
S ta c k L e v e l 1
S ta c k L e v e l 2
S ta c k
P o in te r
B o tto m
C o u n te r
S ta c k L e v e l 3
o f S ta c k
P ro g ra m
M e m o ry
S ta c k L e v e l 8
Arithmetic and Logic Unit – ALU
The arithmetic-logic unit or ALU is a critical area of the microcontroller that carries out arithmetic
and logic operations of the instruction set. Connected to the main microcontroller data bus, the ALU
receives related instruction codes and performs the required arithmetic or logical operations after
which the result will be placed in the specified register. As these ALU calculation or operations may
result in carry, borrow or other status changes, the status register will be correspondingly updated to
reflect these changes. The ALU supports the following functions:
• Arithmetic operations: ADD, ADDM, ADC, ADCM, SUB, SUBM, SBC, SBCM, DAA
• 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. 1.50
20
August 13, 2014
HT67F488/HT67F489
TinyPowerTM A/D 8-Bit Flash MCU with LCD & EEPROM
Flash Program Memory
The Program Memory is the location where the user code or program is stored. For this device series
the Program Memory is Flash type, which means it can be programmed and re-programmed a large
number of times, allowing the user the convenience of code modification on the same device. By
using the appropriate programming tools, the Flash devices offer users the flexibility to conveniently
debug and develop their applications while also offering a means of field programming and
updating.
Structure
The Program Memory has a capacity of 4K×16 bits to 8K×16 bits. The Program Memory is
addressed by the Program Counter and also contains data, table information and interrupt entries.
Table data, which can be setup in any location within the Program Memory, is addressed by a
separate table pointer register.
Device
Capacity
HT67F488
4K×16
HT67F489
8K×16
Special Vectors
Within the Program Memory, certain locations are reserved for the reset and interrupts. The location
000H is reserved for use by the device reset for program initialisation. After a device reset is
initiated, the program will jump to this location and begin execution.
  
  
 Program Memory Structure
Rev. 1.50
21
August 13, 2014
TinyPower
TM
HT67F488/HT67F489
A/D 8-Bit Flash MCU with LCD & 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 memory [m] is located in
current page. If the memory [m] is located in other pages, the table data can be retrieved from the
Program Memory using the “LTABRD [m]” or “LTABRDL [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 “F00H” which refers to the start
address of the last page within the 4K Program Memory of the HT67F488 device. 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 “F06H” 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]” or “LTABRD [m]” instruction is being used. The high byte of the table data which in
this case is equal to zero will be transferred to the TBLH register automatically when the “TABRD
[m]” or “LTABRD [m]” instruction is executed.
Because the TBLH register is 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.
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TinyPowerTM A/D 8-Bit Flash MCU with LCD & EEPROM
Table Read Program Example
tempreg1 db ? ; temporary register #1 in current page
tempreg2 db ? ; temporary register #2 in current page
:
:
mov a,06h ; initialise low table pointer - note that this address is
; referenced to the last page or present page
mov tblp,a
:
:
tabrdl tempreg1 ; transfers value in table referenced by table pointer to tempreg1
; Data at program memory address “F06H” transferred to tempreg1
; and TBLH
dec tblp ; reduce value of table pointer by one
tabrdl tempreg2 ; transfers value in table referenced by table pointer to tempreg2
; Data at program memory address “F05H” transferred to tempreg2
; and TBLH
; in this example the data “1AH” is transferred to tempreg1 and
; data “0FH” to register tempreg2 while the value “00H” will be
; transferred the high byte register TBLH
:
:
org F00h; sets initial address of program memory
dc 00Ah, 00Bh, 00Ch, 00Dh, 00Eh, 00Fh, 01Ah, 01Bh
:
:
In Circuit Programming – ICP
The provision of Flash type Program Memory provides the user with a means of convenient and easy
upgrades and modifications to their programs on the same device. As an additional convenience,
Holtek has provided a means of programming the microcontroller in-circuit using a 4-pin interface.
This provides manufacturers with the possibility of manufacturing their circuit boards complete with
a programmed or un-programmed microcontroller, and then programming or upgrading the program
at a later stage. This enables product manufacturers to easily keep their manufactured products
supplied with the latest program releases without removal and re-insertion of the device.
The Holtek Flash MCU to Writer Programming Pin correspondence table is as follows:
Holtek Writer Pins
MCU Programming Pins
ICPDA
PA0
Programming Serial Data/Address
Pin Description
ICPCK
PA2
Programming Clock
VDD
VDD
Power Supply
VSS
VSS
Ground
The Program Memory and EEPROM data Memory can both be programmed serially in-circuit using
this 4-wire interface. Data is downloaded and uploaded serially on a single pin with an additional
line for the clock. Two additional lines are required for the power supply. The technical details
regarding the in-circuit programming of the devices are beyond the scope of this document and will
be supplied in supplementary literature.
During the programming process, taking control of the PA0 and PA2 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.
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A/D 8-Bit Flash MCU with LCD & EEPROM
W r ite r C o n n e c to r
S ig n a ls
M C U
W r ite r _ V D D
V D D
IC P D A
P A 0
IC P C K
P A 2
W r ite r _ V S S
V S S
*
P r o g r a m m in g
P in s
*
T o o th e r C ir c u it
Note: * may be resistor or capacitor. The resistance of * must be greater than 1k or the capacitance
of * must be less than 1nF.
On-Chip Debug Support – OCDS
There is an EV chip named HT67V489 which is used to emulate the HT67F488/HT67F489 series
of devices. The HT67V489 device also provides the “On-Chip Debug” function to debug the
HT67F488/HT67F489 series of devices during development process. The devices, HT67F488/
HT67F489 and HT67V489, are almost functional compatible except the “On-Chip Debug” function
and package types. Users can use the HT67V489 device to emulate the HT67F488/HT67F489
series of devices behaviors by connecting the OCDSDA and OCDSCK pins to the Holtek HTIDE development tools. The OCDSDA pin is the OCDS Data/Address input/output pin while the
OCDSCK pin is the OCDS clock input pin. When users use the HT67V489 EV chip for debugging,
the corresponding pin functions shared with the OCDSDA and OCDSCK pins in the HT67F488/
HT67F489 series of devices will have no effect in the HT67V489 EV chip. However, the two
OCDS pins which are pin-shared with the ICP programming pins are still used as the Flash Memory
programming pins for ICP. For more detailed OCDS information, refer to the corresponding
document named “Holtek e-Link for 8-bit MCU OCDS User’s Guide”.
Rev. 1.50
Holtek e-Link Pins
EV Chip Pins
OCDSDA
OCDSDA
On-chip Debug Support Data/Address input/output
Pin Description
OCDSCK
OCDSCK
On-chip Debug Support Clock input
VDD
VDD
Power Supply
VSS
VSS
Ground
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RAM Data Memory
The Data Memory is an 8-bit wide RAM internal memory and is the location where temporary
information is stored.
Divided into two types, the first of Data Memory is an area of RAM where special function registers
are located. These registers have fixed locations and are necessary for correct operation of the
device. Many of these registers can be read from and written to directly under program control,
however, some remain protected from user manipulation. The second area of Data Memory is
reserved for general purpose use. All locations within this area are read and write accessible under
program control.
Structure
The Data Memory is divided into several sectors, all of which are implemented in 8-bit wide
Memory. Each of the Data Memory sectors is categorized into two types, the Special Purpose Data
Memory and the General Purpose Data Memory.
The start address of the Special Purpose Data Memory for all devices is the address 00H while the
start address of the General Purpose Data Memory is the address 80H. The Special Purpose Data
Memory registers are accessible in all sectors, with the exception of the EEC register at address
40H, which is only accessible in Sector 1.
Device
HT67F488
HT67F489
Capacity
Sectors
General Purpose: 256×8
0: 80H~FFH
1: 80H~93H (For LCD)
2: 80H~FFH
  Data Memory Structure
General Purpose Data Memory
There are 256 bytes of general purpose memory which are arranged in 80H~FFH of Sector 0,
Sector 2 separately. And another 20 bytes of LCD memory are mapped in 80H~93H of Sector 1. All
microcontroller programs require an area of read/write memory where temporary data can be stored
and retrieved for use later. It is this area of RAM memory that is known as General Purpose Data
Memory. The general purpose data memory is fully accessible by the user program for both read and
writing operations. By using the "SET [m].i" and "CLR [m].i" instructions individual bits can be set
or reset under program control giving the user a large range of flexibility for bit manipulation in the
Data Memory.
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Special Purpose Data Memory
This area of Data Memory is where registers, necessary for the correct operation of the
microcontroller, are stored. They are overlapped in any sector. Most of the registers are both
readable and writable but some are protected and are readable only, the details of which are located
under the relevant Special Function Register section. Note that for locations that are unused before
80H, any read instruction to these addresses will return the value "00H".
    
              
     Special Purpose Data Memory
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Special Function Register Description
Most of the Special Function Register details will be described in the relevant functional sections,
however several registers require a separate description in this section.
Indirect Addressing Register – IAR0, IAR1, IAR2
The Indirect Addressing Registers, IAR0, IAR1 and IAR2, although having their locations in normal
RAM register space, do not actually physically exist as normal registers. The method of indirect
addressing for RAM data manipulation uses these Indirect Addressing Registers and Memory
Pointers, in contrast to direct memory addressing, where the actual memory address is specified.
Actions on the IAR0, IAR1 and IAR2 registers will result in no actual read or write operation to
these registers but rather to the memory location specified by their corresponding Memory Pointers,
MP0, MP1L/MP1H or MP2L/MP2H. Acting as a pair, IAR0 and MP0 can together access data
only from Sector 0 while the IAR1 register together with MP1L/MP1H register pair and IAR2
register together with MP2L/MP2H register pair can access data from any Data Memory sector. As
the Indirect Addressing Registers are not physically implemented, reading the Indirect Addressing
Registers indirectly will return a result of “00H” and writing to the registers indirectly will result in
no operation.
Memory Pointers – MP0, MP1L, MP1H, MP2L, MP2H
Five Memory Pointers, known as MP0, MP1L, MP1H, MP2L and MP2H, are provided. These
Memory Pointers are physically implemented in the Data Memory and can be manipulated in the
same way as normal registers providing a convenient way with which to address and track data.
When any operation to the relevant Indirect Addressing Registers is carried out, the actual address
that the microcontroller is directed to is the address specified by the related Memory Pointer. MP0,
together with Indirect Addressing Register, IAR0, are used to access data from Sector 0, while
MP1L/MP1H together with IAR1 and MP2L/MP2H together with IAR2 are used to access data
from all data sectors according to the corresponding MP1H or MP2H register. Direct Addressing can
be used in all data sectors using the corresponding instruction which can address all available data
memory space.
The following example shows how to clear a sector of four Data Memory locations already defined
as locations adres1 to adres4.
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Indirect Addressing Program Example
data.section ‘data’
adres1 db?
adres2 db?
adres3 db?
adres4 db?
block db?
code.section at 0 code
org 00h
start:
mov
a, 04h;
mov block, a
mov a, offset adres1 ;
mov mp0, a ;
loop:
clr IAR0 ;
inc
mp0;
sdz block ;
jmploop
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
Data Memory addresses.
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.
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Look-up Table Registers – TBLP, TBHP, TBLH
These three special function registers are used to control operation of the look-up table which is
stored in the Program Memory. TBLP and TBHP are the table pointer and indicates the location
where the table data is located. Their value must be setup before any table read commands are
executed. Their value can be changed, for example using the “INC” or “DEC” instructions, allowing
for easy table data pointing and reading. TBLH is the location where the high order byte of the table
data is stored after a table read data instruction has been executed. Note that the lower order table
data byte is transferred to a user defined location.
Status Register – STATUS
This 8-bit register contains the SC flag, CZ flag, zero flag (Z), carry flag (C), auxiliary carry flag (AC),
overflow flag (OV), power down flag (PDF), and watchdog time-out flag (TO). These arithmetic/
logical operation and system management flags are used to record the status and operation of the
microcontroller.
With the exception of the TO and PDF flags, bits in the status register can be altered by instructions
like most other registers. Any data written into the status register will not change the TO or PDF flag.
In addition, operations related to the status register may give different results due to the different
instruction operations. The TO flag can be affected only by a system power-up, a WDT time-out or
by executing the “CLR WDT” or “HALT” instruction. The PDF flag is affected only by executing
the “HALT” or “CLR WDT” instruction or during a system power-up.
The Z, OV, AC, C, SC and CZ flags generally reflect the status of the latest operations.
• SC is the result of the “XOR” operation which is performed by the OV flag and the MSB of the
current instruction operation result.
• CZ is the operational result of different flags for different instuctions. Refer to register definitions
for more details.
• 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.
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A/D 8-Bit Flash MCU with LCD & EEPROM
STATUS Register
Bit
7
6
5
4
3
2
1
0
Name
SC
CZ
TO
PDF
OV
Z
AC
C
R/W
R/W
R/W
R
R
R/W
R/W
R/W
R/W
POR
x
x
0
0
x
x
x
x
“x” unknown
Bit 7SC: The result of the “XOR” operation which is performed by the OV flag and the
MSB of the instruction operation result.
Bit 6CZ: The the operational result of different flags for different instructions.
For SUB/SUBM instructions, the CZ flag is equal to the Z flag.
For SBC/SBCM instructions, the CZ flag is the “AND” operation result which is
performed by the previous operation CZ flag and current operation zero flag.
For other instructions, the CZ flag will not be affected.
Bit 5TO: Watchdog Time-Out flag
0: After power up or executing the “CLR WDT” or “HALT” instruction
1: A watchdog time-out occurred.
Bit 4PDF: Power down flag
0: After power up or executing the “CLR WDT” instruction
1: By executing the “HALT” instruction
Bit 3OV: Overflow flag
0: No overflow
1: An operation results in a carry into the highest-order bit but not a carry out of the
highest-order bit or vice versa.
Bit 2Z: Zero flag
0: The result of an arithmetic or logical operation is not zero
1: The result of an arithmetic or logical operation is zero
Bit 1AC: Auxiliary flag
0: No auxiliary carry
1: An operation results in a carry out of the low nibbles in addition, or no borrow
from the high nibble into the low nibble in subtraction
Bit 0C: Carry flag
0: No carry-out
1: An operation results in a carry during an addition operation or if a borrow does
not take place during a subtraction operation
C is also affected by a rotate through carry instruction.
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EEPROM Data Memory
The HT67F489 device contains an area of internal EEPROM Data Memory. EEPROM, which
stands for Electrically Erasable Programmable Read Only Memory, is by its nature a non-volatile
form of re-programmable memory, with data retention even when its power supply is removed.
By incorporating this kind of data memory, a whole new host of application possibilities are made
available to the designer. The availability of EEPROM storage allows information such as product
identification numbers, calibration values, specific user data, system setup data or other product
information to be stored directly within the product microcontroller. The process of reading and
writing data to the EEPROM memory has been reduced to a very trivial affair.
EEPROM Data Memory Structure
The EEPROM Data Memory capacity is 64×8 bits for the device. Unlike the Program Memory
and RAM Data Memory, the EEPROM Data Memory is not directly mapped into memory space
and is therefore not directly addressable in the same way as the other types of memory. Read and
Write operations to the EEPROM are carried out in single byte operations using an address and data
register in Sector 0 and a single control register in Sector 1.
EEPROM Registers
Three registers control the overall operation of the internal EEPROM Data Memory. These are
the address register, EEA, the data register, EED and a single control register, EEC. As both the
EEA and EED registers are located in Sector 0, they can be directly accessed in the same was as
any other Special Function Register. The EEC register however, being located in Sector1, cannot
be directly addressed directly and can only be read from or written to indirectly using the MP1L/
MP1H Memory Pointer and Indirect Addressing Register, IAR1. Because the EEC control register is
located at address 40H in Sector 1, the MP1L Memory Pointer low byte must first be set to the value
40H and the MP1H Memory Pointer high byte set to the value 01H before any operations on the
EEC register are executed.
EEPROM Register List
Name
Bit
7
6
5
4
3
2
1
0
EEA
—
—
D5
D4
D3
D2
D1
D0
EED
D7
D6
D5
D4
D3
D2
D1
D0
EEC
—
—
—
—
WREN
WR
RDEN
RD
EEA Register
Bit
7
6
5
4
3
2
1
0
Name
—
—
D5
D4
D3
D2
D1
D0
R/W
—
—
R/W
R/W
R/W
R/W
R/W
R/W
POR
—
—
0
0
0
0
0
0
Bit 7~6
Unimplemented, read as “0”
Bit 5~0D5~D0: Data EEPROM address
Data EEPROM address bit 5 ~ bit 0
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EED Register
Bit
7
6
5
4
3
2
1
0
Name
D7
D6
D5
D4
D3
D2
D1
D0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
0
0
0
0
0
0
0
Bit 7~0D7~D0: Data EEPROM data
Data EEPROM data bit 7 ~ bit 0
EEC Register
Bit
7
6
5
4
3
2
1
0
Name
—
—
—
—
WREN
WR
RDEN
RD
R/W
—
—
—
—
R/W
R/W
R/W
R/W
POR
—
—
—
—
0
0
0
0
Bit 7~4
Unimplemented, read as “0”
Bit 3WREN: Data EEPROM Write Enable
0: Disable
1: Enable
This is the Data EEPROM Write Enable Bit which must be set high before Data
EEPROM write operations are carried out. Clearing this bit to zero will inhibit Data
EEPROM write operations.
Bit 2WR: EEPROM Write Control
0: Write cycle has finished
1: Activate a write cycle
This is the Data EEPROM Write Control Bit and when set high by the application
program will activate a write cycle. This bit will be automatically reset to zero by the
hardware after the write cycle has finished. Setting this bit high will have no effect if
the WREN has not first been set high.
Bit 1RDEN: Data EEPROM Read Enable
0: Disable
1: Enable
This is the Data EEPROM Read Enable Bit which must be set high before Data
EEPROM read operations are carried out. Clearing this bit to zero will inhibit Data
EEPROM read operations.
Bit 0RD: EEPROM Read Control
0: Read cycle has finished
1: Activate a read cycle
This is the Data EEPROM Read Control Bit and when set high by the application
program will activate a read cycle. This bit will be automatically reset to zero by the
hardware after the read cycle has finished. Setting this bit high will have no effect if
the RDEN has not first been set high.
Note: The WREN, WR, RDEN and RD can not be set to “1” at the same time in one instruction. The
WR and RD can not be set to “1” at the same time.
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Reading Data from the EEPROM
To read data from the EEPROM, the read enable bit, RDEN, in the EEC register must first be set
high to enable the read function. The EEPROM address of the data to be read must then be placed
in the EEA register. If the RD bit in the EEC register is now set high, a read cycle will be initiated.
Setting the RD bit high will not initiate a read operation if the RDEN bit has not been set. When
the read cycle terminates, the RD bit will be automatically cleared to zero, after which the data can
be read from the EED register. The data will remain in the EED register until another read or write
operation is executed. The application program can poll the RD bit to determine when the data is
valid for reading.
Writing Data to the EEPROM
The EEPROM address of the data to be written must first be placed in the EEA register and the data
placed in the EED register. To write data to the EEPROM, the write enable bit, WREN, in the EEC
register must first be set high to enable the write function. After this, the WR bit in the EEC register
must be immediately set high to initiate a write cycle. These two instructions must be executed
consecutively. The global interrupt bit EMI should also first be cleared before implementing any
write operations, and then set again after the write cycle has started. 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 MP1L/MP1H and MP2L/MP2H will be reset to zero, which means
that Data Memory Sector 0 will be selected. As the EEPROM control register is located in Sector 1,
this adds a further measure of protection against spurious write operations. During normal program
operation, ensuring that the Write Enable bit in the control register is cleared will safeguard against
incorrect write operations.
EEPROM Interrupt
The EEPROM write interrupt is generated when an EEPROM write cycle has ended. The EEPROM
interrupt must first be enabled by setting the DEE bit in the relevant interrupt register. However as
the EEPROM is contained within a Multi-function Interrupt, the associated multi-function interrupt
enable bit must also be set. When an EEPROM write cycle ends, the DEF request flag and its
associated multi-function interrupt request flag will both be set. If the global, EEPROM and Multifunction interrupts are enabled and the stack is not full, a jump to the associated Multi-function
Interrupt vector will take place. When the interrupt is serviced only the Multi-function interrupt flag
will be automatically reset, the EEPROM interrupt flag must be manually reset by the application
program. More details can be obtained in the Interrupt section.
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A/D 8-Bit Flash MCU with LCD & EEPROM
Programming Considerations
Care must be taken that data is not inadvertently written to the EEPROM. Protection can be
enhanced by ensuring that the Write Enable bit is normally cleared to zero when not writing.
Also the Memory Pointer high byte, MP1H or MP2H, could be normally cleared to zero as this
would inhibit access to Sector 1 where the EEPROM control register exist. Although certainly not
necessary, consideration might be given in the application program to the checking of the validity
of new write data by a simple read back process. When writing data the WR bit must be set high
immediately after the WREN bit has been set high, to ensure the write cycle executes correctly. The
global interrupt bit EMI should also be cleared before a write cycle is executed and then re-enabled
after the write cycle starts. Note that the device should not enter the IDLE or SLEEP mode until
the EEPROM read or write operation is totally complete. Otherwise, the EEPROM read or write
operation will fail.
Programming Examples
Reading data from the EEPROM - polling method
MOV A, EEPROM_ADRES MOV EEA, A
MOV A, 040H MOV MP1L, A MOV A, 01H MOV MP1H, A
SET IAR1.1 SET IAR1.0 BACK:
SZ IAR1.0 JMP BACK
CLR IAR1 CLR MP1H
MOV A, EED MOV READ_DATA, A
; user defined address
; setup memory pointer MP1L
; MP1 points to EEC register
; setup memory pointer MP1H
; set RDEN bit, enable read operations
; start Read Cycle - set RD bit
; check for read cycle end
; disable EEPROM read/write
; move read data to register
Writing Data to the EEPROM - polling method
MOV A, EEPROM_ADRES
MOV EEA, A
MOV A, EEPROM_DATA
MOV EED, A
MOV A, 040H MOV MP1L, A MOV A, 01H MOV MP1H, A
CLR EMI
SET IAR1.3 SET IAR1.2 set WREN bit
SET EMI
BACK:
SZ IAR1.2 JMP BACK
CLR IAR1 CLR MP1H
Rev. 1.50
; user defined address
; user defined data
; setup memory pointer MP1L
; MP1 points to EEC register
; setup memory pointer MP1H
; set WREN bit, enable write operations
; start Write Cycle - set WR bit – executed immediately after
; check for write cycle end
; disable EEPROM read/write
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TinyPowerTM A/D 8-Bit Flash MCU with LCD & 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 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. The higher frequency
oscillators provide higher performance but carry with it the disadvantage of higher power
requirements, while the opposite is of course true for the lower frequency oscillators. With the
capability of dynamically switching between fast and slow system clock, the device has the
flexibility to optimize the performance/power ratio, a feature especially important in power sensitive
portable applications.
Type
Name
Freq.
Pins
HIRC
8MHz
—
External High speed Crystal
HXT
400kHz~16MHz
OSC1/OSC2
Internal Low Speed RC
LIRC
32kHz
—
External Low Speed Crystal
LXT
32.768kHz
XT1/XT2
Internal High Speed RC
Oscillator Types
System Clock Configurations
There are three methods of generating the system clock, one high speed oscillator and two low
speed oscillators. The high speed oscillator is the internal 8MHz RC oscillator - HIRC. The two low
speed oscillators are the internal 32kHz RC oscillator - LIRC and the external 32.768kHz crystal
oscillator - LXT. 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. 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.
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Rev. 1.50
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August 13, 2014
TinyPower
TM
HT67F488/HT67F489
A/D 8-Bit Flash MCU with LCD & EEPROM
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. An additional configuration option must be setup
to configure the device according to whether the oscillator frequency is high, defined as equal to or
above 1MHz, or low, which is defined as below 1MHz.
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
Crystal Oscillator C1 and C2 Values
Crystal Frequency
C1
C2
12MHz
0pF
0pF
8MHz
0pF
0pF
4MHz
0pF
0pF
1MHz
100pF
100pF
455kHz (see Note2)
100pF
100pF
Note: 1. C1 and C2 values are for guidance only.
2. XTAL mode configuration option: 455kHz.
Crystal Recommended Capacitor Values
Internal RC Oscillator – HIRC
The internal RC oscillator is a fully integrated system oscillator requiring no external components.
The internal RC oscillator has a fixed frequency of 8MHz. 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. Note that if this internal system clock option is selected, as it
requires no external pins for its operation, I/O pins are free for use as normal I/O pins.
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TinyPowerTM A/D 8-Bit Flash MCU with LCD & 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 the FSUBC register. This clock source has a fixed frequency of 32.768kHz and
requires a 32.768kHz crystal to be connected between pins XT1 and XT2. The external resistor and
capacitor components connected to the 32.768kHz crystal are necessary to provide oscillation. For
applications where precise frequencies are essential, these components may be required to provide
frequency compensation due to different crystal manufacturing tolerances. During power-up there is
a time delay associated with the LXT oscillator waiting for it to start-up.
When the microcontroller enters the SLEEP or IDLE Mode, the system clock is switched off to stop
microcontroller activity and to conserve power. However, in many microcontroller applications
it may be necessary to keep the internal timers operational even when the microcontroller is in
the SLEEP or IDLE Mode. To do this, another clock, independent of the system clock, must be
provided.
However, for some crystals, to ensure oscillation and accurate frequency generation, it is necessary
to add two small value external capacitors, C1 and C2. The exact values of C1 and C2 should
be selected in consultation with the crystal or resonator manufacturer specification. The external
parallel feedback resistor, RP, is required.
The FSUBC register determines 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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  ‚  External LXT Oscillator
LXT Oscillator C1 and C2 Values
Crystal Frequency
C1
C2
32.768kHz
10pF
10pF
Note: 1. C1 and C2 values are for guidance only.
2. RP=5M~10MΩ is recommended.
32.768kHz Crystal Recommended Capacitor Values
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TinyPower
TM
HT67F488/HT67F489
A/D 8-Bit Flash MCU with LCD & 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 FSUBC register.
FSUBC Register
Bit
7
6
5
4
3
2
1
0
Name
LXTLP
FSUB6
FSUB5
FSUB4
FSUB3
FSUB2
FSUB1
FSUB0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
0
1
0
1
0
1
0
Bit 7LXTLP: LXT Low Power Control
0: Quick Start Mode
1: Low Power Mode
Bit 6~0
FSUB6~FSUB0: fSUB clock source selection
0101010: LIRC
1010101: LXT
Others: MCU reset
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 Lowpower mode.
Internal 32kHz Oscillator – LIRC
The Internal 32kHz System Oscillator is one of the low frequency oscillator choices, which is
selected via the FSUBC register. 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%.
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HT67F488/HT67F489
TinyPowerTM A/D 8-Bit Flash MCU with LCD & EEPROM
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 device has many different clock sources for both the CPU and peripheral function operation.
By providing the user with a wide range of clock options using configuration options and register
programming, a clock system can be configured to obtain maximum application performance.
The main system clock, can come from either a high frequency fH or low frequency fSUB source,
and is selected using the HLCLK bit and CKS2~CKS0 bits in the SMOD register. The high speed
system clock can be sourced from the HIRC/HXT oscillator. The low speed system clock source
can be sourced from internal clock fSUB. If fSUB is selected then it can be sourced by either the LXT
or LIRC oscillator, selected by the FSUB6~FSUB0 bits in the FSUBC register. The other choice,
which is a divided version of the high speed system oscillator has a range of fH/2~fH/64.
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System Clock Configuration
Note: When the system clock source fSYS is switched to fSUB from fH, the high speed oscillation will stop to
conserve the power. Thus there is no fH~fH/64 for peripheral circuit to use.
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TinyPower
TM
HT67F488/HT67F489
A/D 8-Bit Flash MCU with LCD & EEPROM
System Operation Modes
There are six different modes of operation for the microcontroller, each one with its own
special characteristics and which can be chosen according to the specific performance and
power requirements of the application. There are two modes allowing normal operation of the
microcontroller, the NORMAL Mode and SLOW Mode. The remaining four modes, the SLEEP0,
SLEEP1, IDLE0 and IDLE1 Mode are used when the microcontroller CPU is switched off to
conserve power.
Operating Mode
Description
CPU
fSYS
fSUB
fTBC
NORMAL Mode
On
fH~fH/64
On
On
SLOW Mode
On
fSUB
On
On
IDLE0 Mode
Off
Off
On
On
IDLE1 Mode
Off
On
On
On
SLEEP0 Mode
Off
Off
Off
Off
SLEEP1 Mode
Off
Off
On
Off
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 the high speed oscillator HIRC/HXT. The high speed oscillator will however first be divided
by a ratio ranging from 1 to 64, the actual ratio being selected by the CKS2~CKS0 and HLCLK
bits in the SMOD register. Although a high speed oscillator is used, running the microcontroller at a
divided clock ratio reduces the operating current.
SLOW Mode
This is also a mode where the microcontroller operates normally although now with a slower speed
clock source. The clock source used will be from one of the low speed oscillators, either the LXT
or the LIRC. Running the microcontroller in this mode allows it to run with much lower operating
currents. In the SLOW Mode, the fH is off.
SLEEP0 Mode
The SLEEP Mode is entered when an HALT instruction is executed and when the IDLEN bit in the
SMOD register is low. In the SLEEP0 mode the CPU will be stopped, and the fSUB clock will be
stopped too, and the Watchdog Timer function is disabled. In this mode, the LVDEN is must set to “0”.
If the LVDEN is set to “1”, it won’t enter the SLEEP0 Mode.
SLEEP1 Mode
The SLEEP Mode is entered when an HALT instruction is executed and when the IDLEN bit in the
SMOD register is low. In the SLEEP1 mode the CPU will be stopped. However the fSUB clock will
continue to operate if the LVDEN is “1” or the Watchdog Timer function is enabled.
IDLE0 Mode
The IDLE0 Mode is entered when a HALT instruction is executed and when the IDLEN bit in the
SMOD register is high and the FSYSON bit in the CTRL register is low. In the IDLE0 Mode the
system oscillator will be inhibited from driving the CPU, the system oscillator will be stopped, the
low frequency clock fSUB will be on.
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HT67F488/HT67F489
TinyPowerTM A/D 8-Bit Flash MCU with LCD & EEPROM
IDLE1 Mode
The IDLE1 Mode is entered when a HALT instruction is executed and when the IDLEN bit in the
SMOD register is high and the FSYSON bit in the CTRL register is high. In the IDLE1 Mode the
system oscillator will be inhibited from driving the CPU, 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
low frequency clock fSUB will be on.
Note: If LVDEN=1 and the SLEEP or IDLE mode is entered, the LVD and bandgap functions
will not be disabled, and the fSUB clock will be forced to be enabled. In sleep mode, other
peripheral will disable except WDT, LVD if enable in SLEEP 1.
Control Register
A single register, SMOD, is used for overall control of the internal clocks within the device.
SMOD Register
Bit
7
6
5
4
3
2
1
0
Name
CKS2
CKS1
CKS0
—
LTO
HTO
IDLEN
HLCLK
R/W
R/W
R/W
R/W
—
R
R
R/W
R/W
POR
0
0
0
—
0
0
1
1
Bit 7~5CKS2~CKS0: The system clock selection when HLCLK is “0”
000: fSUB (fLXT or fLIRC)
001: fSUB (fLXT or fLIRC)
010: fH/64
011: fH/32
100: fH/16
101: fH/8
110: fH/4
111: fH/2
These three bits are used to select which clock is used as the system clock source. In
addition to the system clock source, which can be either the LXT or LIRC, a divided
version of the high speed system oscillator can also be chosen as the system clock
source.
Bit 4
Unimplemented, read as “0”
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 the device is
powered on and then changes to a high level after the high speed system oscillator is
stable.
Therefore this flag will always be read as “1” by the application program after device
power-on. The flag will be low when in the SLEEP or IDLE0 Mode but after a wakeup has occurred, the flag will change to a high level after 15~16 clock cycles if the
HIRC/HXT oscillator is used.
Rev. 1.50
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August 13, 2014
TinyPower
TM
HT67F488/HT67F489
A/D 8-Bit Flash MCU with LCD & EEPROM
Bit 1IDLEN: IDLE Mode control
0: Disable
1: Enable
This is the IDLE Mode Control bit and determines what happens when the HALT
instruction is executed. If this bit is high, when a HALT instruction is executed the
device will enter the IDLE Mode. In the IDLE1 Mode the CPU will stop running
but the system clock will continue to keep the peripheral functions operational, if
FSYSON bit is high. If FSYSON bit is low, the CPU and the system clock will all stop
in IDLE0 mode. If the bit is low the device will enter the SLEEP Mode when a HALT
instruction is executed.
Bit 0HLCLK: System clock selection
0: fH/2 ~ fH/64 or fSUB
1: fH
This bit is used to select if the fH clock or the fH/2~fH/64 or fSUB clock is used as
the system clock. When the bit is high the fH clock will be selected and if low the
fH/2~fH/64 or fSUB clock will be selected. When system clock switches from the fH
clock to the fSUB clock and the fH clock will be automatically switched off to conserve
power.
CTRL Register
Bit
7
6
5
4
3
2
1
0
Name
FSYSON
—
—
—
FSUBF
LVRF
LRF
WRF
R/W
R/W
—
—
—
R/W
R/W
R/W
R/W
POR
0
—
—
—
0
x
0
0
“x” unknown
Bit 7FSYSON: fSYS Control in IDLE Mode
0: Disable
1: Enable
Bit 6~4
Unimplemented, read as “0”
Bit 3FSUBF: FSUBC Control register software reset flag
0: Not occur
1: Occurred
This bit is set to 1 if the FSUB6~FSUB0 bits in the FSUBC register contains any
undefined values. This bit can only be cleared to 0 by the application program.
Bit 2LVRF: LVR function reset flag
0: Not occur
1: Occurred
This bit is set to 1 when a specific Low Voltage Reset situation condition occurs. This
bit can only be cleared to 0 by the application program.
Bit 1LRF: LVR Control register software reset flag
0: Not occur
1: Occurred
This bit is set to 1 if the LVRC register contains any non defined LVR voltage register
values. This in effect acts like a software reset function. This bit can only be cleared to
0 by the application program.
Bit 0WRF: WDT Control register software reset flag
0: Not occur
1: Occurred
This bit is set to 1 by the WDT Control register software reset and cleared by the
application program. Note that this bit can only be cleared to 0 by the application
program.
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HT67F488/HT67F489
TinyPowerTM A/D 8-Bit Flash MCU with LCD & EEPROM
Operating Mode Switching
The device can switch between operating modes dynamically allowing the user to select the best
performance/power ratio for the present task in hand. In this way microcontroller operations that
do not require high performance can be executed using slower clocks thus requiring less operating
current and prolonging battery life in portable applications.
In simple terms, Mode Switching between the NORMAL Mode and SLOW Mode is executed
using the HLCLK bit and CKS2~CKS0 bits in the SMOD register while Mode Switching from the
NORMAL/SLOW Modes to the SLEEP/IDLE Modes is executed via the HALT instruction. When
a HALT instruction is executed, whether the device enters the IDLE Mode or the SLEEP Mode is
determined by the condition of the IDLEN bit in the SMOD register and FSYSON in the CTRL
register.
When the HLCLK bit switches to a low level, which implies that clock source is switched from the
high speed clock source, fH, to the clock source, fH/2~fH/64 or fSUB. If the clock is from the fSUB, the
high speed clock source will stop running to conserve power. When this happens it must be noted
that the fH/16 and fH/64 internal clock sources will also stop running, which may affect the operation
of other internal functions such as the TMs. The accompanying flowchart shows what happens when
the device moves between the various operating modes.
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August 13, 2014
TinyPower
TM
HT67F488/HT67F489
A/D 8-Bit Flash MCU with LCD & EEPROM
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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44
August 13, 2014
HT67F488/HT67F489
TinyPowerTM A/D 8-Bit Flash MCU with LCD & EEPROM
SLOW Mode to NORMAL Mode Switching
In SLOW Mode the system uses either the LXT or LIRC low speed system oscillator. To switch
back to the NORMAL Mode, where the high speed system oscillator is used, the HLCLK bit should
be set to “1” or HLCLK bit is “0”, but CKS2~CKS0 is set to “010”, “011”, “100”, “101”, “110”
or “111”. As a certain amount of time will be required for the high frequency clock to stabilise,
the status of the HTO bit is checked. The amount of time required for high speed system oscillator
stabilization depends upon which high speed system oscillator type is used.
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45
August 13, 2014
TinyPower
TM
HT67F488/HT67F489
A/D 8-Bit Flash MCU with LCD & EEPROM
Entering the SLEEP0 Mode
There is only one way for the device to enter the SLEEP0 Mode and that is to execute the “HALT”
instruction in the application program with the IDLEN bit in SMOD register equal to “0” and the
WDT and LVD both off. When this instruction is executed under the conditions described above, the
following will occur:
• The system clock, WDT clock and Time Base clock will be stopped and the application program
will stop at the “HALT” instruction.
• The Data Memory contents and registers will maintain their present condition.
• The WDT will be cleared and stopped.
• The I/O ports will maintain their present conditions.
• In the status register, the Power Down flag, PDF, will be set and the Watchdog time-out flag, TO,
will be cleared.
Entering the SLEEP1 Mode
There is only one way for the device to enter the SLEEP1 Mode and that is to execute the “HALT”
instruction in the application program with the IDLEN bit in SMOD register equal to “0” and the
WDT or LVD on. When this instruction is executed under the conditions described above, the
following will occur:
• The system clock and Time Base clock will be stopped and the application program will stop at
the “HALT” instruction, but the WDT or LVD will remain with the clock source coming from the
fSUB clock.
• The Data Memory contents and registers will maintain their present condition.
• The WDT will be cleared and resume counting if the WDT is enabled.
• The I/O ports will maintain their present conditions.
• In the status register, the Power Down flag, PDF, will be set and the Watchdog time-out flag, TO,
will be cleared.
Entering the IDLE0 Mode
There is only one way for the device to enter the IDLE0 Mode and that is to execute the “HALT”
instruction in the application program with the IDLEN bit in SMOD register equal to “1” and the
FSYSON bit in CTRL register equal to “0”. When this instruction is executed under the conditions
described above, the following will occur:
• The system clock will be stopped and the application program will stop at the “HALT”
instruction, but the Time Base clock fTBC and fSUB clock will be on.
• The Data Memory contents and registers will maintain their present condition.
• The WDT will be cleared and resume counting if the WDT is enabled.
• The I/O ports will maintain their present conditions.
• In the status register, the Power Down flag, PDF, will be set and the Watchdog time-out flag, TO,
will be cleared.
Entering the IDLE1 Mode
There is only one way for the device to enter the IDLE1 Mode and that is to execute the “HALT”
instruction in the application program with the IDLEN bit in SMOD register equal to “1” and the
FSYSON bit in CTRL register equal to “1”. When this instruction is executed under the conditions
described above, the following will occur:
• The system clock, Time Base clock fTBC 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.
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HT67F488/HT67F489
TinyPowerTM A/D 8-Bit Flash MCU with LCD & EEPROM
• The WDT will be cleared and resume counting if the WDT is enabled.
• The I/O ports will maintain their present conditions.
• In the status register, the Power Down flag, PDF, will be set and the Watchdog time-out flag, TO,
will be cleared.
Standby Current Considerations
As the main reason for entering the SLEEP or IDLE Mode is to keep the current consumption of the
device to as low a value as possible, perhaps only in the order of several micro-amps except in the
IDLE1 Mode, there are other considerations which must also be taken into account by the circuit
designer if the power consumption is to be minimised. Special attention must be made to the I/O pins
on the device. All high-impedance input pins must be connected to either a fixed high or low level as
any floating input pins could create internal oscillations and result in increased current consumption.
This also applies to devices which have different package types, as there may be unbonbed pins.
These must either be setup as outputs or if setup as inputs must have pull-high resistors connected.
Care must also be taken with the loads, which are connected to I/O pins, which are setup as outputs.
These should be placed in a condition in which minimum current is drawn or connected only to
external circuits that do not draw current, such as other CMOS inputs. Also note that additional
standby current will also be required if enabled the LXT or LIRC oscillator.
In the IDLE1 Mode the system oscillator is on, if the system oscillator is from the high speed system
oscillator, the additional standby current will also be perhaps in the order of several hundred microamps.
Wake-up
After the system enters the SLEEP or IDLE Mode, it can be woken up from one of various sources
listed as follows:
• An external falling edge on Port A
• A system interrupt
• A WDT overflow
If the device is woken up by a WDT overflow, a Watchdog Timer reset will be initiated. 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 the device will not
be immediately serviced, but will rather be serviced later when the related interrupt is finally enabled
or when a stack level becomes free. The other situation is where the related interrupt is enabled and
the stack is not full, in which case the regular interrupt response takes place. If an interrupt request
flag is set high before entering the SLEEP or IDLE Mode, the wake-up function of the related
interrupt will be disabled.
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TinyPower
TM
HT67F488/HT67F489
A/D 8-Bit Flash MCU with LCD & EEPROM
Watchdog Timer
The Watchdog Timer is provided to prevent program malfunctions or sequences from jumping to
unknown locations, due to certain uncontrollable external events such as electrical noise.
Watchdog Timer Clock Source
The Watchdog Timer clock source is provided by the internal clock, fSUB, the fSUB clock is sourced
from LIRC or LXT oscillator selected by the FSUBC register. The Watchdog Timer source clock is
then subdivided by a ratio of 28 to 218 to give longer timeouts, the actual value being chosen using
the WS2~WS0 bits in the WDTC register. The LIRC internal oscillator has an approximate period
of 32kHz at a supply voltage of 5V. However, it should be noted that this specified internal clock
period can vary with VDD, temperature and process variations. The LXT oscillator is supplied by an
external 32.768kHz crystal.
Watchdog Timer Control Register
A single register, WDTC, controls the required timeout period as well as the enable/disable
operation.
WDTC Register
Bit
7
6
5
4
3
2
1
0
Name
WE4
WE3
WE2
WE1
WE0
WS2
WS1
WS0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
1
0
1
0
0
1
1
Bit 7~3WE4~WE0: WDT function software control
10101: Disable
01010: Enable
Others: Reset MCU
When these bits are changed by the environmental noise to reset the microcontroller,
the reset operation will be activated after 2~3 LIRC clock cycles and the WRF bit in
the CTRL register will be set to 1.
Bit 2~0WS2~WS0: WDT time-out period selection
000: 28/fSUB
001: 210/fSUB
010: 212/fSUB
011: 214/fSUB
100: 215/fSUB
101: 216/fSUB
110: 217/fSUB
111: 218/fSUB
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TinyPowerTM A/D 8-Bit Flash MCU with LCD & EEPROM
CTRL Register
Bit
7
6
5
4
3
2
1
0
Name
FSYSON
—
—
—
FSUBF
R/W
R/W
—
—
—
R/W
LVRF
LRF
WRF
R/W
R/W
POR
0
—
—
—
0
R/W
x
0
0
“x” unknown
Bit 7FSYSON: fSYS Control in IDLE Mode
Described elsewhere.
Bit 6~4
Unimplemented, read as “0”
Bit 3FSUBF: FSUBC Control register software reset flag
Described elsewhere.
Bit 2LVRF: LVR function reset flag
Described elsewhere.
Bit 1LRF: LVR Control register software reset flag
Described elsewhere.
Bit 0WRF: WDT Control register software reset flag
0: Not occur
1: Occurred
This bit is set to 1 by the WDT Control register software reset and cleared by the
application program. Note that this bit can only be cleared to 0 by the application
program.
Watchdog Timer Operation
The Watchdog Timer operates by providing a device reset when its timer overflows. This means
that in the application program and during normal operation the user has to strategically clear the
Watchdog Timer before it overflows to prevent the Watchdog Timer from executing a reset. This is
done using the clear watchdog instructions. If the program malfunctions for whatever reason, jumps
to an unknown location, or enters an endless loop, these clear instructions will not be executed in the
correct manner, in which case the Watchdog Timer will overflow and reset the device. With regard
to the Watchdog Timer enable/disable function, there are also five bits, WE4~WE0, in the WDTC
register to offer additional enable/disable and reset control of the Watchdog Timer. The WDT
function will be disabled when the WE4~WE0 bits are set to a value of 10101B. The WDT function
will be enabled if the WE4~WE0 bits value is equal to 01010B. If the WE4~WE0 bits are set to any
other values by the environmental noise or software setting, except 01010B and 10101B, it will reset
the device after 2~3 fSUB clock cycles. After power on these bits will have the value of 01010B.
WE4 ~ WE0 Bits
10101B
WDT Function
Disable
01010B
Enable
Any other value
Reset MCU
Watchdog Timer Enable/Disable Control
Under normal program operation, a Watchdog Timer time-out will initialise a device reset and set
the status bit TO. However, if the system is in the SLEEP or IDLE Mode, when a Watchdog Timer
time-out occurs, the TO bit in the status register will be set and only the Program Counter and Stack
Pointer will be reset. Three methods can be adopted to clear the contents of the Watchdog Timer.
The first is a WDT reset, which means a certain value except 01010B and 10101B written into the
WE4~WE0 bit filed, the second is using the Watchdog Timer software clear instructions and the
third is via a HALT instruction.
Rev. 1.50
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TinyPower
TM
HT67F488/HT67F489
A/D 8-Bit Flash MCU with LCD & EEPROM
There is only one method of using software instruction to clear the Watchdog Timer. That is to use
the single “CLR WDT” instruction to clear the WDT.
The maximum time out period is when the 218 division ratio is selected. As an example, with a
32kHz LIRC oscillator as its source clock, this will give a maximum watchdog period of around 8
second for the 218 division ratio, and a minimum timeout of 7.8ms for the 28 division ration.
WDTC Register
Reset MCU
WE4~WE0 bits
CLR
“HALT”Instruction
“CLR WDT”Instruction
M
U
X
LXT
LIRC
fSUB
FSUBC
FSUB6~FSUB0 bits
8-stage Divider
fSUB/28
WDT Prescaler
WS2~WS0
(fSUB/28 ~ fSUB/218)
8-to-1 MUX
WDT Time-out
(28/fSUB ~ 218/fSUB)
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.
Another type of reset is when the Watchdog Timer overflows and resets. All types of reset operations
result in different register conditions being setup. Another reset exists in the form of a Low Voltage
Reset, LVR, where a full reset is implemented in situations where the power supply voltage falls
below a certain threshold.
Reset Functions
There are four ways in which a reset can occur, 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 I/O ports will be first set to inputs.
VDD
Power-on
Reset
tRSTD
SST Time-out
Note: tRSTD is power-on delay, typical time=50ms
Power-On Reset Timing Chart
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TinyPowerTM A/D 8-Bit Flash MCU with LCD & EEPROM
• Low Voltage Reset — LVR
The microcontroller contains a low voltage reset circuit in order to monitor the supply voltage of
the device. The LVR function is always enabled with a specific LVR voltage VLVR. If the supply
voltage of the device drops to within a range of 0.9V~VLVR such as might occur when changing
the battery, the LVR will automatically reset the device internally and the LVRF bit in the CTRL
register will also be set to 1. For a valid LVR signal, a low supply voltage, i.e., a voltage in the
range between 0.9V~VLVR must exist for a time greater than that specified by tLVR in the A.C.
characteristics. If the low supply voltage state does not exceed this value, the LVR will ignore the
low supply voltage and will not perform a reset function. The actual VLVR value can be selected
by the LVS bits in the LVRC register. If the LVS7~LVS0 bits are changed to some certain
values by the environmental noise or software setting, the LVR will reset the device after 2~3
LIRC clock cycles. When this happens, the LRF bit in the CTRL register will be set to 1. After
power on the register will have the value of 01010101B. Note that the LVR function will be
automatically disabled when the device enters the power down mode.
Note: tRSTD is power-on delay, typical time=50ms
Low Voltage Reset Timing Chart
LVRC Register
Bit
7
6
5
4
3
2
1
0
Name
LVS7
LVS6
LVS5
LVS4
LVS3
LVS2
LVS1
LVS0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
1
0
1
0
1
0
1
Bit 7~0LVS7~LVS0: LVR voltage select
01010101: 2.1V
00110011: 2.55V
10011001: 3.15V
10101010: 3.8V
Any other value: Generates MCU reset -- LVRC register is reset to POR value
When an actual low voltage condition occurs, as specified by one of the four defined
LVR voltage values above, an MCU reset will be generated. The reset operation will
be activated after 2~3 fSUB clock cycles. In this situation the register contents will
remain the same after such a reset occurs.
Any register value, other than the four defined LVR values above, will also result in
the generation of an MCU reset. The reset operation will be activated after 2~3 fSUB
clock cycles. However in this situation the register contents will be reset to the POR
value.
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TinyPower
TM
HT67F488/HT67F489
A/D 8-Bit Flash MCU with LCD & EEPROM
CTRL Register
Bit
7
6
5
4
3
2
1
0
Name
FSYSON
—
—
—
FSUBF
R/W
R/W
—
—
—
R/W
LVRF
LRF
WRF
R/W
R/W
POR
0
—
—
—
0
R/W
x
0
0
“x” unknown
Bit 7FSYSON: fSYS Control in IDLE Mode
Described elsewhere.
Bit 6~4
Unimplemented, read as “0”
Bit 3FSUBF: FSUBC Control register software reset flag
Described elsewhere.
Bit 2LVRF: LVR function reset flag
0: Not occur
1: Occurred
This bit can be clear to “0”, but can not set to “1”.
Bit 1LRF: LVR Control register software reset flag
0: Not occur
1: Occurred
This bit is set to 1 if the LVRC register contains any non defined LVR voltage register
values. This in effect acts like a software reset function. This bit can only be cleared to
0 by the application program.
Bit 0WRF: WDT Control register software reset flag
Described elsewhere.
• Watchdog Time-out Reset during Normal Operation
The Watchdog time-out Reset during normal operation is the same as LVR reset except that the
Watchdog time-out flag TO will be set to "1".
Note: tRSTD is power-on delay, typical time=16.7ms
WDT Time-out Reset during Normal Operation Timing Chart
• Watchdog Time-out Reset during SLEEP or IDLE Mode
The Watchdog time-out Reset during SLEEP or IDLE Mode is a little different from other kinds
of reset. Most of the conditions remain unchanged except that the Program Counter and the Stack
Pointer will be cleared to “0” and the TO flag will be set to “1”. Refer to the A.C. Characteristics
for tSST details.
Note: The tSST is 15~16 clock cycles if the system clock source is provided by HIRC/HXT.
The tSST is 1024 clock for LXT. The tSST is 1~2 clock for LIRC.
WDT Time-out Reset during Sleep or IDLE Timing Chart
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TinyPowerTM A/D 8-Bit Flash MCU with LCD & 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
LVR reset during Normal or SLOW Mode operation
1
u
WDT time-out reset during Normal or SLOW Mode operation
1
1
WDT time-out reset during IDLE or SLEEP Mode operation
Note: “u” stands for unchanged
The following table indicates the way in which the various components of the microcontroller are
affected after a power-on reset occurs.
Item
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~AN9 as A/D input pins
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.
Power On Reset
LVR Reset
WDT Time-out
(Normal Operation)
WDT Time-out
(HALT)
IAR0
xxxx xxxx
uuuu uuuu
uuuu uuuu
uuuu uuuu
MP0
xxxx xxxx
uuuu uuuu
uuuu uuuu
uuuu uuuu
IAR1
xxxx xxxx
uuuu uuuu
uuuu uuuu
uuuu uuuu
MP1L
xxxx xxxx
uuuu uuuu
uuuu uuuu
uuuu uuuu
MP1H
xxxx xxxx
uuuu uuuu
uuuu uuuu
uuuu uuuu
IAR2
xxxx xxxx
uuuu uuuu
uuuu uuuu
uuuu uuuu
MP2L
xxxx xxxx
uuuu uuuu
uuuu uuuu
uuuu uuuu
MP2H
xxxx xxxx
uuuu uuuu
uuuu uuuu
uuuu uuuu
ACC
xxxx xxxx
uuuu uuuu
uuuu uuuu
uuuu uuuu
PCL
0000 0000
0000 0000
0000 0000
0000 0000
TBLP
xxxx xxxx
uuuu uuuu
uuuu uuuu
uuuu uuuu
TBLH
xxxx xxxx
uuuu uuuu
uuuu uuuu
uuuu uuuu
TBHP
---x xxxx
---u uuuu
---u uuuu
---u uuuu
STATUS
xx00 xxxx
uuuu uuuu
uu1u uuuu
uu11 uuuu
SMOD
000- 0011
000- 0011
000- 0011
uuu- uuuu
LVDC
--00 -000
--00 -000
--00 -000
--uu -uuu
LVRC
0101 0101
0101 0101
0101 0101
uuuu uuuu
Register
CTRL
0--- 0x00
0--- uuuu
0--- uuuu
0--- uuuu
INTEG
0000 0000
0000 0000
0000 0000
uuuu uuuu
Rev. 1.50
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TinyPower
TM
HT67F488/HT67F489
A/D 8-Bit Flash MCU with LCD & EEPROM
Power On Reset
LVR Reset
WDT Time-out
(Normal Operation)
WDT Time-out
(HALT)
WDTC
0101 0011
0101 0011
0101 0011
uuuu uuuu
TBC
0011 -111
0011 -111
0011 -111
uuuu -uuu
INTC0
-000 0000
-000 0000
-000 0000
-uuu uuuu
INTC1
0000 0000
0000 0000
0000 0000
uuuu uuuu
INTC2
-000 -000
-000 -000
-000 -000
-uuu -uuu
MFI0
--00 --00
--00 --00
--00 --00
--uu --uu
MFI1
--00 --00
--00 --00
--00 --00
--uu --uu
MFI2
--00 --00
--00 --00
--00 --00
--uu --uu
MFI3
--00 --00
--00 --00
--00 --00
--uu --uu
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
Register
PCC
1111 1111
1111 1111
1111 1111
uuuu uuuu
PDPU
0000 0000
0000 0000
0000 0000
uuuu uuuu
PD
1111 1111
1111 1111
1111 1111
uuuu uuuu
PDC
1111 1111
1111 1111
1111 1111
uuuu uuuu
PEPU
0000 0000
0000 0000
0000 0000
uuuu uuuu
PE
1111 1111
1111 1111
1111 1111
uuuu uuuu
PEC
1111 1111
1111 1111
1111 1111
uuuu uuuu
PFPU
0000 ----
0000 ----
0000 ----
uuuu ----
PF
1111 ----
1111 ----
1111 ----
uuuu ----
PFC
1111 ----
1111 ----
1111 ----
uuuu ----
TMPC
---0 0000
---0 0000
---0 0000
---u uuuu
IOHR0
0000 0000
0000 0000
0000 0000
uuuu uuuu
IOHR1
0000 0000
0000 0000
0000 0000
uuuu uuuu
ADRL (ADRFS=0)
xxxx ----
xxxx ----
xxxx ----
uuuu ----
ADRL (ADRFS=1)
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
ADRH (ADRFS=0)
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
ADRH (ADRFS=1)
---- xxxx
---- xxxx
---- xxxx
---- uuuu
0110 0000
0110 0000
0110 0000
uuuu uuuu
ADCR0
ADCR1
00-0 -000
00-0 -000
00-0 -000
uu-u -uuu
ACERL
1111 1111
1111 1111
1111 1111
uuuu uuuu
ACERH
---- --11
---- --11
---- --11
---- --uu
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HT67F488/HT67F489
TinyPowerTM A/D 8-Bit Flash MCU with LCD & EEPROM
Register
Power On Reset
LVR Reset
WDT Time-out
(Normal Operation)
WDT Time-out
(HALT)
TM0C0
0000 0---
0000 0---
0000 0---
uuuu u---
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
TM0RPL
0000 0000
0000 0000
0000 0000
uuuu uuuu
TM0RPH
---- --00
---- --00
---- --00
---- --uu
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
TM2C0
0000 0000
0000 0000
0000 0000
uuuu uuuu
TM2C1
0000 0000
0000 0000
0000 0000
uuuu uuuu
TM2DL
0000 0000
0000 0000
0000 0000
uuuu uuuu
TM2DH
---- --00
---- --00
---- --00
---- --uu
TM2AL
0000 0000
0000 0000
0000 0000
uuuu uuuu
TM2AH
---- --00
---- --00
---- --00
---- --uu
TM3C0
0000 0000
0000 0000
0000 0000
uuuu uuuu
TM3C1
0000 0000
0000 0000
0000 0000
uuuu uuuu
TM3DL
0000 0000
0000 0000
0000 0000
uuuu uuuu
TM3DH
---- --00
---- --00
---- --00
---- --uu
TM3AL
0000 0000
0000 0000
0000 0000
uuuu uuuu
TM3AH
---- --00
---- --00
---- --00
---- --uu
FSUBC
0010 1010
0010 1010
0010 1010
uuuu uuuu
LCDC0
0000 -000
0000 -000
0000 -000
uuuu -uuu
LCDC1
000- 0000
000- 0000
000- 0000
uuu- uuuu
SEGCR0
0000 0000
0000 0000
0000 0000
uuuu uuuu
SEGCR1
0000 0000
0000 0000
0000 0000
uuuu uuuu
SEGCR2
---- 0000
---- 0000
---- 0000
---- uuuu
EEA
--00 0000
--00 0000
--00 0000
--uu uuuu
EED
0000 0000
0000 0000
0000 0000
uuuu uuuu
EEC
---- 0000
---- 0000
---- 0000
---- uuuu
USR
0000 1011
0000 1011
0000 1011
uuuu uuuu
UCR1
0000 00x0
0000 00x0
0000 00x0
uuuu uuuu
UCR2
0000 0000
0000 0000
0000 0000
uuuu uuuu
BRG
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
TXR/RXR
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
Note: “u” stands for unchanged
“x” stands for unknown
“-” stands for unimplemented
Rev. 1.50
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TinyPower
TM
HT67F488/HT67F489
A/D 8-Bit Flash MCU with LCD & 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.
The device provides bidirectional input/output lines labeled with port names PA~PF. These I/O ports
are mapped to the RAM Data Memory with specific addresses as shown in the Special Purpose
Data Memory table. All of these I/O ports can be used for input and output operations. For input
operation, these ports are non-latching, which means the inputs must be ready at the T2 rising edge
of instruction “MOV A, [m]”, where m denotes the port address. For output operation, all the data is
latched and remains unchanged until the output latch is rewritten.
I/O Register List
Bit
Register
Name
7
6
5
4
3
2
1
0
PAWU
PAWU7
PAWU6
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
PDPU
PDPU7
PDPU6
PDPU5
PDPU4
PDPU3
PDPU2
PDPU1
PDPU0
PD
PD7
PD6
PD5
PD4
PD3
PD2
PD1
PD0
PDC
PDC7
PDC6
PDC5
PDC4
PDC3
PDC2
PDC1
PDC0
PEPU
PEPU7
PEPU6
PEPU5
PEPU4
PEPU3
PEPU2
PEPU1
PEPU0
PE
PE7
PE6
PE5
PE4
PE3
PE2
PE1
PE0
PEC
PEC7
PEC6
PEC5
PEC4
PEC3
PEC2
PEC1
PEC0
PFPU
PFPU7
PFPU6
PFPU5
PFPU4
—
—
—
—
PF
PF7
PF6
PF5
PF4
—
—
—
—
PFC
PFC7
PFC6
PFC5
PFC4
—
—
—
—
“—”: Unimplemented, read as “0”
PAWUn: PA wake-up function control
0: Disable
1: Enable
PAn/PBn/PCn/PDn/PEn/PFn: I/O Data bit
0: Data 0
1: Data 1
PACn/PBCn/PCCn/PDCn/PECn/PFCn: I/O type selection
0: Output
1: Input
PAPUn/PBPUn/PCPUn/PDPUn/PEPUn/PFPUn: Pull-high function control
0: Disable
1: Enable
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Pull-high Resistors
Many product applications require pull-high resistors for their switch inputs usually requiring the
use of an external resistor. To eliminate the need for these external resistors, all I/O pins, when
configured as an input have the capability of being connected to an internal pull-high resistor. These
pull-high resistors are selected using registers PAPU~PFPU, and are implemented using weak
PMOS transistors.
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 bit 7 ~ bit 0 Wake-up Control
0: Disable
1: Enable
I/O Port Control Registers
Each I/O port has its own control register known as PAC~PFC, to control the input/output
configuration. With this control register, each CMOS output or input can be reconfigured
dynamically under software control. Each pin of the I/O ports is directly mapped to a bit in its
associated port control register. For the I/O pin to function as an input, the corresponding bit of the
control register must be written as a “1”. This will then allow the logic state of the input pin to be
directly read by instructions. When the corresponding bit of the control register is written as a “0”,
the I/O pin will be setup as a CMOS output. If the pin is currently setup as an output, instructions
can still be used to read the output register. However, it should be noted that the program will in fact
only read the status of the output data latch and not the actual logic status of the output pin.
Pin-shared 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. For these pins, the
chosen function of the multi-function I/O pins is selected by a series of registers via the application
program control.
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A/D 8-Bit Flash MCU with LCD & 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.
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      ­ €   Generic Input/Output Structure
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A/D Input/Output Structure
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Programming Considerations
Within the user program, one of the first things to consider is port initialisation. After a reset, all of
the I/O data and port control registers will be set high. This means that all I/O pins will default to
an input state, the level of which depends on the other connected circuitry and whether pull-high
selections have been chosen. If the port control registers, PAC~PFC, are then programmed to setup
some pins as outputs, these output pins will have an initial high output value unless the associated
port data registers, PA~PF, are first programmed. Selecting which pins are inputs and which are
outputs can be achieved byte-wide by loading the correct values into the appropriate port control
register or by programming individual bits in the port control register using the “SET [m].i” and
“CLR [m].i” instructions. Note that when using these bit control instructions, a read-modify-write
operation takes place. The microcontroller must first read in the data on the entire port, modify it to
the required new bit values and then rewrite this data back to the output ports.
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.
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TM
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A/D 8-Bit Flash MCU with LCD & EEPROM
Timer Modules – TM
One of the most fundamental functions in any microcontroller device is the ability to control and
measure time. To implement time related functions each device includes several Timer Modules,
abbreviated to the name TM. The TMs are multi-purpose timing units and serve to provide
operations such as Timer/Counter, Input Capture, Compare Match Output and Single Pulse Output
as well as being the functional unit for the generation of PWM signals. Each of the TMs has two
individual interrupts. The addition of input and output pins for each TM ensures that users are
provided with timing units with a wide and flexible range of features.
The common features of the different TM types are described here with more detailed information
provided in the individual Compact and Periodic TM sections.
Introduction
These devices contain four TMs having a reference name of TM0, TM1, TM2 and TM3. Each
individual TM can be categorised as a certain type, namely Compact Type TM or Periodic Type TM.
Although similar in nature, the different TM types vary in their feature complexity. The common
features to all of the Compact and Periodic TMs will be described in this section, the detailed
operation regarding each of the TM types will be described in separate sections. The main features
and differences between the two types of TMs are summarised in the accompanying table.
Function
CTM
PTM
Timer/Counter
√
√
I/P Capture
—
√
Compare Match Output
√
√
PWM Channels
1
1
Single Pulse Output
PWM Alignment
PWM Adjustment Period & Duty
—
1
Edge
Edge
Duty or Period
Duty or Period
TM Function Summary
This chip contains a specific number of either Compact Type and Periodic Type TM units which are
shown in the table together with their individual reference names, TM0~TM3.
TM0
TM1
TM2
TM3
10-bit PTM
10-bit CTM
10-bit CTM
10-bit CTM
TM Name/Type Reference
TM Operation
The two different types of TM offer a diverse range of functions, from simple timing operations
to PWM signal generation. The key to understanding how the TM operates is to see it in terms of
a free running counter whose value is then compared with the value of pre-programmed internal
comparators. When the free running counter has the same value as the pre-programmed comparator,
known as a compare match situation, a TM interrupt signal will be generated which can clear the
counter and perhaps also change the condition of the TM output pin. The internal TM counter is
driven by a user selectable clock source, which can be an internal clock or an external pin.
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TM Clock Source
The clock source which drives the main counter in each TM can originate from various sources.
The selection of the required clock source is implemented using the TnCK2~TnCK0 bits in the TM
control registers. The clock source can be a ratio of either the system clock fSYS or the internal high
clock fH, the fTBC clock source or the external TCKn pin. The TCKn pin clock source is used to allow
an external signal to drive the TM as an external clock source or for event counting.
TM Interrupts
The Compact Type and Periodic Type TMs each have two internal interrupts, one for each of the
internal comparator A or comparator P, which generate a TM interrupt when a compare match
condition occurs. When a TM interrupt is generated it can be used to clear the counter and also to
change the state of the TM output pin.
TM External Pins
Each of the TMs, irrespective of what type, has one TM input pin, with the label TCKn. The TM
input pin is essentially a clock source for the TM and is selected using the TnCK2~TnCK0 bits in
the TMnC0 register. This external TM input pin allows an external clock source to drive the internal
TM. This external TM input pin is shared with other functions but will be connected to the internal
TM if selected using the TnCK2~TnCK0 bits. The TM input pin can be chosen to have either a
rising or falling active edge.
The TMs each have one or two output pins with the label TPn. When the TM is in the Compare
Match Output Mode, these pins can be controlled by the TM to switch to a high or low level or to
toggle when a compare match situation occurs. The external TPn output pin is also the pin where the
TM generates the PWM output waveform. As the TM output pins are pin-shared with other function,
the TM output function must first be setup using registers. A single bit in one of the registers
determines if its associated pin is to be used as an external TM output pin or if it is to have another
function. The number of output pins for each TM type is different, the details are provided in the
accompanying table.
Periodic Type TM output pin names have a “_n” suffix. Pin names that include a “_0” or “_1”
suffix indicate that they are from a TM with multiple output pins. This allows the TM to generate a
complimentary output pair, selected using the I/O register data bits.
TM0
TM1
TM2
TM3
TP0_0, TP0_1
TP1
TP2
TP3
TM Output Pins
TM Input/Output Pin Control Registers
Selecting to have a TM input/output or whether to retain its other shared functions is implemented
using one register with a single bit in each register corresponding to a TM input/output pin. 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 functions.
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TM
HT67F488/HT67F489
A/D 8-Bit Flash MCU with LCD & EEPROM
TM0 Function Pin Control Block Diagram
TM1 Function Pin Control Block Diagram
TM2 Function Pin Control Block Diagram
TM3 Function Pin Control Block Diagram
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TMPC Register
Bit
7
6
5
4
3
2
1
0
Name
—
—
—
T3CP
T2CP
T1CP
T0CP1
T0CP0
R/W
—
—
—
R/W
R/W
R/W
R/W
R/W
POR
—
—
—
0
0
0
0
0
Bit 7~5
Unimplemented, read as “0”
Bit 4T3CP: TP3 pin control
0: Disable
1: Enable
Bit 3T2CP: TP2 pin control
0: Disable
1: Enable
Bit 2T1CP: TP1 pin control
0: Disable
1: Enable
Bit 1T0CP1: TP0_1 pin control
0: Disable
1: Enable
Bit 0T0CP0: TP0_0 pin control
0: Disable
1: Enable
Programming Considerations
The TM Counter Registers and the Capture/Compare CCRA and CCRP registers, being 10-bit, all
have a low and high byte structure. The high bytes can be directly accessed, but as the low bytes
can only be accessed via an internal 8-bit buffer, reading or writing to these register pairs must be
carried out in a specific way. The important point to note is that data transfer to and from the 8-bit
buffer and its related low byte only takes place when a write or read operation to its corresponding
high byte is executed. As the CCRA and CCRP registers are implemented in the way shown in the
following diagram and accessing the register is carried out in a specific way described above, it
is recommended to use the “MOV” instruction to access the CCRA and CCRP low byte registers,
named TMxAL and TMxRPL, using the following access procedures. Accessing the CCRA or
CCRP low byte register without following these access procedures will result in unpredictable
values.
TM Co�nter Re�ister (Read only)
TMxDL
TMxDH
8-bit B�ffer
TMx�L
TMx�H
TM CCR� Re�ister (Read/Write)
TMxRPL
TMxRPH
TM CCRP Re�ister (Read/Write)
Data B�s
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TM
HT67F488/HT67F489
A/D 8-Bit Flash MCU with LCD & EEPROM
The following steps show the read and write procedures:
• Writing Data to CCRA or CCRP
♦♦
Step 1. Write data to Low Byte TMxAL or TMxRPL
––Note that here data is only written to the 8-bit buffer.
♦♦
Step 2. Write data to High Byte TMxAH or TMxRPH
––Here data is written directly to the high byte registers and simultaneously data is latched
from the 8-bit buffer to the Low Byte registers.
• Reading Data from the Counter Registers and CCRA or CCRP
♦♦
Step 1. Read data from the High Byte TMxDH, TMxAH or TMxRPH
––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 TMxRPL
––This step reads data from the 8-bit buffer.
Periodic Type TM – PTM
The Periodic Type TM contains five operating modes, which are Compare Match Output, Timer/
Event Counter, Capture Input, Single Pulse Output and PWM Output modes. The Periodic TM can
be controlled with an external input pin and can drive two external output pin.
Name
TM No.
TM Input Pin
TM Output Pin
10-bit PTM
0
TCK0
TP0_0, TP0_1
Periodic TM Operation
At its core is a 10-bit count-up counter which is driven by a user selectable internal or external clock
source. There are two internal comparators with the names, Comparator A and Comparator P. These
comparators will compare the value in the counter with the CCRA and CCRP registers.
The only way of changing the value of the 10-bit counter using the application program, is to
clear the counter by changing the TnON bit from low to high. The counter will also be cleared
automatically by a counter overflow or a compare match with one of its associated comparators.
When these conditions occur, a TM interrupt signal will also usually be generated. The Periodic
Type TM can operate in a number of different operational modes, can be driven by different clock
sources including an input pin and can also control the output pin. All operating setup conditions are
selected using relevant internal registers.
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TinyPowerTM A/D 8-Bit Flash MCU with LCD & EEPROM
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Periodic Type TM Block Diagram (n=0)
Periodic Type TM Register Description
Overall operation of the Periodic TM is controlled using a series of registers. A read only register
pair exists to store the internal counter 10-bit value, while two read/write register pairs exist to store
the internal 10-bit CCRA and CCRP value. The remaining two registers are control registers which
setup the different operating and control modes.
Bit
Register
Name
7
6
5
4
3
2
1
0
TMnC0
TnPAU
TnCK2
TnCK1
TnCK0
TnON
—
—
—
TMnC1
TnM1
TnM0
TnIO1
TnIO0
TnOC
TnPOL
TnCAPTS
TnCCLR
TMnDL
D7
D6
D5
D4
D3
D2
D1
D0
TMnDH
—
—
—
—
—
—
D9
D8
TMnAL
D7
D6
D5
D4
D3
D2
D1
D0
TMnAH
—
—
—
—
—
—
D9
D8
TMnRPL
D7
D6
D5
D4
D3
D2
D1
D0
TMnRPH
—
—
—
—
—
—
D9
D8
10-bit Periodic TM Register List (n=0)
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TM
HT67F488/HT67F489
A/D 8-Bit Flash MCU with LCD & EEPROM
TMnC0 Register
Bit
7
6
5
4
3
2
1
0
Name
TnPAU
TnCK2
TnCK1
TnCK0
TnON
—
—
—
R/W
R/W
R/W
R/W
R/W
R/W
—
—
—
POR
0
0
0
0
0
—
—
—
Bit 7TnPAU: TMn Counter Pause Control
0: Run
1: Pause
The counter can be paused by setting this bit high. Clearing the bit to zero restores
normal counter operation. When in a Pause condition the TM will remain powered up
and continue to consume power. The counter will retain its residual value when this bit
changes from low to high and resume counting from this value when the bit changes
to a low value again.
Bit 6~4TnCK2~TnCK0: Select TMn Counter clock
000: fSYS/4
001: fH
010: fH/16
011: fH/64
100: fTBC
101: fTBC
110: TCKn rising edge clock
111: TCKn falling edge clock
These three bits are used to select the clock source for the TM. 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 3TnON: TMn Counter On/Off Control
0: Off
1: On
This bit controls the overall on/off function of the TM. Setting the bit high enables the
counter to run, clearing the bit disables the TM. Clearing this bit to zero will stop the
counter from counting and turn off the TM which will reduce its power consumption.
When the bit changes state from low to high the internal counter value will be reset to
zero, however when the bit changes from high to low, the internal counter will retain
its residual value until the bit returns high again.
If the TM is in the Compare Match Output Mode then the TM output pin will be reset
to its initial condition, as specified by the TM Output control bit, when the bit changes
from low to high.
Bit 2~0
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TMnC1 Register
Bit
7
6
5
4
3
2
1
0
Name
TnM1
TnM0
TnIO1
TnIO0
TnOC
TnPOL
TnCAPTS
TnCCLR
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
0
0
0
0
0
0
0
Bit 7~6TnM1~TnM0: Select TMn Operation Mode
00: Compare Match Output Mode
01: Capture Input Mode
10: PWM Mode or Single Pulse Output Mode
11: Timer/Counter Mode
These bits setup the required operating mode for the TM. To ensure reliable operation
the TM should be switched off before any changes are made to the TnM1 and TnM0
bits. In the Timer/Counter Mode, the TM output pin control must be disabled.
Bit 5~4TnIO1~TnIO0: Select TPn_0, TPn_1 output function
Compare Match Output Mode
00: No change
01: Output low
10: Output high
11: Toggle output
PWM Mode/Single Pulse Output Mode
00: PWM Output inactive state
01: PWM Output active state
10: PWM output
11: Single pulse output
Capture Input Mode
00: Input capture at rising edge of TPn_0, TPn_1, TCKn
01: Input capture at falling edge of TPn_0, TPn_1, TCKn
10: Input capture at falling/rising edge of TPn_0, TPn_1, TCKn
11: Input capture disabled
Timer/counter Mode
Unused
These two bits are used to determine how the TM output pin changes state when a
certain condition is reached. The function that these bits select depends upon in which
mode the TM is running.
In the Compare Match Output Mode, the TnIO1 and TnIO0 bits determine how the
TM output pin changes state when a compare match occurs from the Comparator A.
The TM output pin can be setup to switch high, switch low or to toggle its present state
when a compare match occurs from the Comparator A. When these bits are both zero,
then no change will take place on the output. The initial value of the TM output pin
should be setup using the TnOC bit. Note that the output level requested by the TnIO1
and TnIO0 bits must be different from the initial value setup using the TnOC bit
otherwise no change will occur on the TM output pin when a compare match occurs.
After the TM output pin changes state, it can be reset to its initial level by changing
the level of the TnON bit from low to high.
In the PWM Mode, the TnIO1 and TnIO0 bits determine how the TM output pin
changes state when a certain compare match condition occurs. The PWM output
function is modified by changing these two bits. It is necessary to change the values
of the TnIO1 and TnIO0 bits only after the TM has been switched off. Unpredictable
PWM outputs will occur if the TnIO1 and TnIO0 bits are changed when the TM is
running.
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TM
HT67F488/HT67F489
A/D 8-Bit Flash MCU with LCD & EEPROM
Bit 3TnOC: TPn_0, TPn_1 Output control bit
Compare Match Output Mode
0: Initial low
1: Initial high
PWM Mode/ Single Pulse Output Mode
0: Active low
1: Active high
This is the output control bit for the TM output pin. Its operation depends upon
whether TM is being used in the Compare Match Output Mode or in the PWM Mode/
Single Pulse Output Mode. It has no effect if the TM is in the Timer/Counter Mode. In
the Compare Match Output Mode it determines the logic level of the TM output pin
before a compare match occurs. In the PWM Mode it determines if the PWM signal is
active high or active low.
Bit 2TnPOL: TPn_0, TPn_1 Output polarity Control
0: Non-invert
1: Invert
This bit controls the polarity of the TPn_0, TPn_1 output pin. When the bit is set high
the TM output pin will be inverted and not inverted when the bit is zero. It has no
effect if the TM is in the Timer/Counter Mode.
Bit 1TnCAPTS: TMn capture trigger source select
0: From TPn_0, TPn_1 pin
1: From TCKn pin
Bit 0TnCCLR: Select TMn Counter clear condition
0: TMn Comparatror P match
1: TMn Comparatror A match
This bit is used to select the method which clears the counter. Remember that the
Periodic TM contains two comparators, Comparator A and Comparator P, either of
which can be selected to clear the internal counter. With the TnCCLR bit set high,
the counter will be cleared when a compare match occurs from the Comparator A.
When the bit is low, the counter will be cleared when a compare match occurs from
the Comparator P or with a counter overflow. A counter overflow clearing method can
only be implemented if the CCRP bits are all cleared to zero. The TnCCLR bit is not
used in the PWM, Single Pulse or Input Capture Mode.
TMnDL Register
Bit
7
6
5
4
3
2
1
0
Name
D7
D6
D5
D4
D3
D2
D1
D0
R/W
R
R
R
R
R
R
R
R
POR
0
0
0
0
0
0
0
0
Bit 7~0TMnDL: TMn Counter Low Byte Register bit 7 ~ bit 0
TMn 10-bit Counter bit 7 ~ bit 0
TMnDH Register
Bit
7
6
5
4
3
2
1
0
Name
—
—
—
—
—
—
D9
D8
R/W
—
—
—
—
—
—
R
R
POR
—
—
—
—
—
—
0
0
Bit 7~2
Unimplemented, read as “0”
Bit 1~0TMnDH: TMn Counter High Byte Register bit 1 ~ bit 0
TMn 10-bit Counter bit 9 ~ bit 8
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TMnAL Register
Bit
7
6
5
4
3
2
1
0
Name
D7
D6
D5
D4
D3
D2
D1
D0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
0
0
0
0
0
0
0
Bit 7~0TMnAL: TMn CCRA Low Byte Register bit 7 ~ bit 0
TMn 10-bit CCRA bit 7 ~ bit 0
TMnAH Register
Bit
7
6
5
4
3
2
1
0
Name
—
—
—
—
—
—
D9
D8
R/W
—
—
—
—
—
—
R/W
R/W
POR
—
—
—
—
—
—
0
0
2
1
0
Bit 7~2
Unimplemented, read as “0”
Bit 1~0TMnAH: TMn CCRA High Byte Register bit 1 ~ bit 0
TMn 10-bit CCRA bit 9 ~ bit 8
TMnRPL 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 7~0TMnRPL: TMn CCRP Low Byte Register bit 7 ~ bit 0
TMn 10-bit CCRP bit 7 ~ bit 0
TMnRPH Register
Bit
7
6
5
4
3
2
1
0
Name
—
—
—
—
—
—
D9
D8
R/W
—
—
—
—
—
—
R/W
R/W
POR
—
—
—
—
—
—
0
0
Bit 7~2
Unimplemented, read as "0"
Bit 1~0TMnRPH: TMn CCRP High Byte Register bit 1 ~ bit 0
TMn 10-bit CCRP bit 9 ~ bit 8
Rev. 1.50
69
August 13, 2014
TinyPower
TM
HT67F488/HT67F489
A/D 8-Bit Flash MCU with LCD & EEPROM
Periodic Type TM Operating Modes
The Periodic Type TM can operate in one of five operating modes, Compare Match Output Mode,
PWM Output Mode, Single Pulse Output Mode, Capture Input Mode or Timer/Counter Mode. The
operating mode is selected using the TnM1 and TnM0 bits in the TMnC1 register.
Compare Match Output Mode
To select this mode, bits TnM1 and TnM0 in the TMnC1 register, should be all cleared to 00
respectively. In this mode once the counter is enabled and running it can be cleared by three
methods. These are a counter overflow, a compare match from Comparator A and a compare match
from Comparator P. When the TnCCLR bit is low, there are two ways in which the counter can be
cleared. One is when a compare match occurs from Comparator P, the other is when the CCRP bits
are all zero which allows the counter to overflow. Here both the TnAF and TnPF interrupt request
flags for Comparator Aand Comparator P respectively, will both be generated.
If the TnCCLR bit in the TMnC1 register is high then the counter will be cleared when a compare
match occurs from Comparator A. However, here only the TnAF interrupt request flag will be
generated even if the value of the CCRP bits is less than that of the CCRA registers. Therefore when
TnCCLR is high no TnPF interrupt request flag will be generated. In the Compare Match Output
Mode, the CCRA can not be set to “0”.
As the name of the mode suggests, after a comparison is made, the TM output pin, will change
state. The TM output pin condition however only changes state when a TnAF interrupt request flag
is generated after a compare match occurs from Comparator A. The TnPF interrupt request flag,
generated from a compare match from Comparator P, will have no effect on the TM output pin. The
way in which the TM output pin changes state are determined by the condition of the TnIO1 and
TnIO0 bits in the TMnC1 register. The TM output pin can be selected using the TnIO1 and TnIO0
bits to go high, to go low or to toggle from its present condition when a compare match occurs from
Comparator A. The initial condition of the TM output pin, which is setup after the TnON bit changes
from low to high, is setup using the TnOC bit. Note that if the TnIO1, TnIO0 bits are zero then no
pin change will take place.
Rev. 1.50
70
August 13, 2014
HT67F488/HT67F489
TinyPowerTM A/D 8-Bit Flash MCU with LCD & EEPROM
Co�nter Val�e
Co�nter overflow
CCRP=0
0x�FF
TnCCLR = 0; TnM [1:0] = 00
CCRP > 0
Co�nter cleared by CCRP val�e
CCRP > 0
Co�nter
Restart
Res�me
CCRP
Pa�se
CCR�
Stop
Time
TnON
TnP�U
TnPOL
CCRP Int.
Fla� TnPF
CCR� Int.
Fla� Tn�F
TM O/P Pin
O�tp�t pin set to
initial Level Low
if TnOC=0
O�tp�t not affected by Tn�F
fla�. Remains Hi�h �ntil reset
by TnON bit
O�tp�t To��le with
Tn�F fla�
Here TnIO [1:0] = 11
To��le O�tp�t select
Note TnIO [1:0] = 10
�ctive Hi�h O�tp�t select
O�tp�t Inverts
when TnPOL is hi�h
O�tp�t Pin
Reset to Initial val�e
O�tp�t controlled by
other pin-shared f�nction
Compare Match Output Mode – TnCCLR = 0 (n=0)
Note: 1. With TnCCLR = 0 – a Comparator P match will clear the counter
2. The TM output pin is controlled only by the TnAF flag
3. The output pin is reset to initial state by a TnON bit rising edge
Rev. 1.50
71
August 13, 2014
TinyPower
TM
HT67F488/HT67F489
A/D 8-Bit Flash MCU with LCD & EEPROM
Co�nter Val�e
TnCCLR = 1; TnM [1:0] = 00
CCR� = 0
Co�nter overflow
CCR� > 0 Co�nter cleared by CCR� val�e
0x�FF
CCR�=0
Res�me
CCR�
Pa�se
Stop
Co�nter Restart
CCRP
Time
TnON
TnP�U
TnPOL
No Tn�F fla�
�enerated on
CCR� overflow
CCR� Int.
Fla� Tn�F
CCRP Int.
Fla� TnPF
TnPF not
�enerated
O�tp�t does
not chan�e
TM O/P Pin
O�tp�t pin set to
initial Level Low
if TnOC=0
O�tp�t not affected by
Tn�F fla�. Remains Hi�h
�ntil reset by TnON bit
O�tp�t To��le with
Tn�F fla�
Here TnIO [1:0] = 11
To��le O�tp�t select
Note TnIO [1:0] = 10
�ctive Hi�h O�tp�t select
O�tp�t Inverts
when TnPOL is hi�h
O�tp�t Pin
Reset to Initial val�e
O�tp�t controlled by
other pin-shared f�nction
Compare Match Output Mode – TnCCLR = 1 (n=0)
Note: 1. With TnCCLR = 1 – a Comparator A match will clear the counter
2. The TM output pin is controlled only by the TnAF flag
3. The output pin is reset to initial state by a TnON rising edge
4. The TnPF flag is not generated when TnCCLR = 1
Rev. 1.50
72
August 13, 2014
HT67F488/HT67F489
TinyPowerTM A/D 8-Bit Flash MCU with LCD & EEPROM
Timer/Counter Mode
To select this mode, bits TnM1 and TnM0 in the TMnC1 register should all be set to 11 respectively.
The Timer/Counter Mode operates in an identical way to the Compare Match Output Mode
generating the same interrupt flags. The exception is that in the Timer/Counter Mode the TM output
pin is not used. Therefore the above description and Timing Diagrams for the Compare Match
Output Mode can be used to understand its function. As the TM output pin is not used in this mode,
the pin can be used as a normal I/O pin or other pin-shared function.
PWM Output Mode
To select this mode, bits TnM1 and TnM0 in the TMnC1 register should be set to 10 respectively
and also the TnIO1 and TnIO0 bits should be set to 10 respectively. The PWM function within
the TM is useful for applications which require functions such as motor control, heating control,
illumination control etc. By providing a signal of fixed frequency but of varying duty cycle on the
TM output pin, a square wave AC waveform can be generated with varying equivalent DC RMS
values.
As both the period and duty cycle of the PWM waveform can be controlled, the choice of generated
waveform is extremely flexible. In the PWM mode, the TnCCLR bit has no effect as the PWM
period. Both of the CCRP and CCRA registers are used to generate the PWM waveform, one register
is used to clear the internal counter and thus control the PWM waveform frequency, while the other
one is used to control the duty cycle. The PWM waveform frequency and duty cycle can therefore
be controlled by the values in the CCRA and CCRP registers.
An interrupt flag, one for each of the CCRA and CCRP, will be generated when a compare match
occurs from either Comparator A or Comparator P. The TnOC bit in the TMnC1 register is used to
select the required polarity of the PWM waveform while the two TnIO1 and TnIO0 bits are used to
enable the PWM output or to force the TM output pin to a fixed high or low level. The TnPOL bit is
used to reverse the polarity of the PWM output waveform.
• 10-bit PTM, PWM Mode
CCRP
1~1023
0
Period
1~1023
1024
Duty
CCRA
If fSYS = 8MHz, TM clock source select fSYS/4, CCRP = 512 and CCRA = 128,
The PTM PWM output frequency = (fSYS/4) / (2×256) = fSYS/2048 =3.90625kHz, 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%.
Rev. 1.50
73
August 13, 2014
TinyPower
TM
Counter Value
HT67F488/HT67F489
A/D 8-Bit Flash MCU with LCD & EEPROM
TnM [1:0] = 10
Counter cleared
by CCRP
Counter Reset when
TnON returns high
CCRP
Pause Resume
CCRA
Counter Stop if
TnON bit low
Time
TnON
TnPAU
TnPOL
CCRA Int.
Flag TnAF
CCRP Int.
Flag TnPF
TM O/P Pin
(TnOC=1)
TM O/P Pin
(TnOC=0)
PWM Duty Cycle
set by CCRA
PWM Period
set by CCRP
PWM resumes
operation
Output controlled by
Output Inverts
other pin-shared function
when TnPOL = 1
PWM Mode (n=0)
Note: 1. Here Counter cleared by CCRP
2. A counter clear sets the PWM Period
3. The internal PWM function continues running even when TnIO[1:0] = 00 or 01
4. The TnCCLR bit has no influence on PWM operation
Rev. 1.50
74
August 13, 2014
HT67F488/HT67F489
TinyPowerTM A/D 8-Bit Flash MCU with LCD & EEPROM
Single Pulse Output Mode
To select this mode, the required bit pairs, TnM1 and TnM0 should be set to 10 respectively and also
the corresponding TnIO1 and TnIO0 bits should be set to 11 respectively. The Single Pulse Output
Mode, as the name suggests, will generate a single shot pulse on the TM output pin.
The trigger for the pulse output leading edge is a low to high transition of the TnON bit, which can
be implemented using the application program. However in the Single Pulse Mode, the TnON bit
can also be made to automatically change from low to high using the external TCKn pin, which will
in turn initiate the Single Pulse output. When the TnON bit transitions to a high level, the counter
will start running and the pulse leading edge will be generated. The TnON bit should remain high
when the pulse is in its active state. The generated pulse trailing edge will be generated when the
TnON bit is cleared to zero, which can be implemented using the application program or when a
compare match occurs from Comparator A.
However a compare match from Comparator A will also automatically clear the TnON bit and thus
generate the Single Pulse output trailing edge. In this way the CCRA value can be used to control the
pulse width. A compare match from Comparator A will also generate TM interrupts. The counter can
only be reset back to zero when the TnON bit changes from low to high when the counter restarts. In
the Single Pulse Mode CCRP is not used. The TnCCLR bit is also not used.
            Single Pulse Generation (n=0)
Rev. 1.50
75
August 13, 2014
TinyPower
TM
Co�nter Val�e
HT67F488/HT67F489
A/D 8-Bit Flash MCU with LCD & EEPROM
TnM [1:0] = 10 ; TnIO [1:0] = 11
Co�nter stopped
by CCR�
Co�nter Reset when
TnON ret�rns hi�h
CCR�
Pa�se
Co�nter Stops
by software
Res�me
CCRP
Time
TnON
Software
Tri��er
��to. set by
TCKn pin
Cleared by
CCR� match
TCKn pin
Software
Tri��er
Software
Software Tri��er
Clear
Software
Tri��er
TCKn pin
Tri��er
TnP�U
TnPOL
No CCRP Interr�pts
�enerated
CCRP Int.
Fla� TnPF
CCR� Int.
Fla� Tn�F
TM O/P Pin
(TnOC=1)
TM O/P Pin
(TnOC=0)
O�tp�t Inverts
when TnPOL = 1
P�lse Width
set by CCR�
Single Pulse Mode (n=0)
Note: 1. Counter stopped by CCRA
2. CCRP is not used
3. The pulse is triggered by the TCKn pin or by setting the TnON bit high
4. A TCKn pin active edge will automatically set the TnON bit high
5. In the Single Pulse Mode, TnIO [1:0] must be set to “11” and can not be changed.
Rev. 1.50
76
August 13, 2014
HT67F488/HT67F489
TinyPowerTM A/D 8-Bit Flash MCU with LCD & EEPROM
Capture Input Mode
To select this mode bits TnM1 and TnM0 in the TMnC1 register should be set to 01 respectively.
This mode enables external signals to capture and store the present value of the internal counter
and can therefore be used for applications such as pulse width measurements. The external signal is
supplied on the TPn_0, TPn_1 or TCKn pin, selected by the TnCAPTS bit in the TMnC0 register.
The input pin active edge can be either a rising edge, a falling edge or both rising and falling edges;
the active edge transition type is selected using the TnIO1 and TnIO0 bits in the TMnC1 register.
The counter is started when the TnON bit changes from low to high which is initiated using the
application program.
When the required edge transition appears on the TPn_0, TPn_1 or TCKn pin the present value in
the counter will be latched into the CCRA register and a TM interrupt generated. Irrespective of
what events occur on the TPn_0, TPn_1 or TCKn pin the counter will continue to free run until the
TnON bit changes from high to low. When a CCRP compare match occurs the counter will reset
back to zero; in this way the CCRP value can be used to control the maximum counter value. When
a CCRP compare match occurs from Comparator P, a TM interrupt will also be generated. Counting
the number of overflow interrupt signals from the CCRP can be a useful method in measuring long
pulse widths. The TnIO1 and TnIO0 bits can select the active trigger edge on the TPn_0, TPn_1
or TCKn pin to be a rising edge, falling edge or both edge types. If the TnIO1 and TnIO0 bits are
both set high, then no capture operation will take place irrespective of what happens on the TPn_0,
TPn_1 or TCKn pin, however it must be noted that the counter will continue to run.
As the TPn_0, TPn_1 or TCKn pin is pin shared with other functions, care must be taken if the TMn
is in the Capture Input Mode. This is because if the pin is setup as an output, then any transitions on
this pin may cause an input capture operation to be executed. The TnCCLR, TnOC and TnPOL bits
are not used in this Mode.
Rev. 1.50
77
August 13, 2014
TinyPower
TM
HT67F488/HT67F489
A/D 8-Bit Flash MCU with LCD & EEPROM
Counter Value
TnM [1:0] = 01
Counter cleared
by CCRP
Counter Counter
Stop
Reset
CCRP
YY
Pause
Resume
XX
Time
TnON
TnPAU
TM capture
pin TPn_x
or TCKn
Active
edge
Active
edge
Active edge
CCRA Int.
Flag TnAF
CCRP Int.
Flag TnPF
CCRA
Value
TnIO [1:0]
Value
XX
00 – Rising edge
YY
01 – Falling edge
XX
10 – Both edges
YY
11 – Disable Capture
Capture Input Mode (n=0)
Note: 1. TnM[1:0] = 01 and active edge set by the TnIO[1:0] bits
2. A TM Capture input pin active edge transfers counter value to CCRA
3. The TnCCLR bit is not used
4. No output function – TnOC and TnPOL bits are not used
5. CCRP determines the counter value and the counter has a maximum count value when CCRP is equal to
zero
Rev. 1.50
78
August 13, 2014
HT67F488/HT67F489
TinyPowerTM A/D 8-Bit Flash MCU with LCD & EEPROM
Compact Type TM – CTM
Although the simplest form of the three 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 external output
pin.
Name
TM No.
TM Input Pin
TM Output Pin
10-bit CTM
1, 2, 3
TCK1, TCK2, TCK3
TP1, TP2, TP3
Compact TM Operation
At its core is a 10-bit count-up counter which is driven by a user selectable internal or external clock
source. There are also two internal comparators with the names, Comparator A and Comparator
P. These comparators will compare the value in the counter with CCRP and CCRA registers. The
CCRP is three bits wide whose value is compared with the highest three bits in the counter while the
CCRA is the ten bits and therefore compares with all counter bits.
The only way of changing the value of the 10-bit counter using the application program, is to
clear the counter by changing the TnON bit from low to high. The counter will also be cleared
automatically by a counter overflow or a compare match with one of its associated comparators.
When these conditions occur, a TM interrupt signal will also usually be generated. The Compact
Type TM can operate in a number of different operational modes, can be driven by different clock
sources including an input pin and can also control an output pin. All operating setup conditions are
selected using relevant internal registers.
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             
 
 
 
      Compact Type TM Block Digram (n=1~3)
Rev. 1.50
79
August 13, 2014
TinyPower
TM
HT67F488/HT67F489
A/D 8-Bit Flash MCU with LCD & 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
TMnC0
TnPAU
TnCK2
TnCK1
TnCK0
TnON
TnRP2
TnRP1
TnRP0
TMnC1
TnM1
TnM0
TnIO1
TnIO0
TnOC
TnPOL
TnDPX
TnCCLR
TMnDL
D7
D6
D5
D4
D3
D2
D1
D0
TMnDH
—
—
—
—
—
—
D9
D8
TMnAL
D7
D6
D5
D4
D3
D2
D1
D0
TMnAH
—
—
—
—
—
—
D9
D8
Compact TM Register List (n=1~3)
TMnC0 Register
Bit
7
6
5
4
3
2
1
0
Name
TnPAU
TnCK2
TnCK1
TnCK0
TnON
TnRP2
TnRP1
TnRP0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
0
0
0
0
0
0
0
Bit 7TnPAU: TMn Counter Pause Control
0: Run
1: Pause
The counter can be paused by setting this bit high. Clearing the bit to zero restores
normal counter operation. When in a Pause condition the TM will remain powered up
and continue to consume power. The counter will retain its residual value when this bit
changes from low to high and resume counting from this value when the bit changes
to a low value again.
Bit 6~4TnCK2~TnCK0: Select TMn Counter clock
000: fSYS/4
001: fH
010: fH/16
011: fH/64
100: fTBC
101: fTBC
110: TCKn rising edge clock
111: TCKn falling edge clock
These three bits are used to select the clock source for the TM. 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 3TnON: TMn Counter On/Off Control
0: Off
1: On
This bit controls the overall on/off function of the TM. Setting the bit high enables the
counter to run, clearing the bit disables the TM. Clearing this bit to zero will stop the
counter from counting and turn off the TM which will reduce its power consumption.
When the bit changes state from low to high the internal counter value will be reset
to zero, however when the bit changes from high to low, the internal counter will
retain its residual value. If the TM is in the Compare Match Output Mode then the TM
output pin will be reset to its initial condition, as specified by the TnOC bit, when the
TnON bit changes from low to high.
Rev. 1.50
80
August 13, 2014
HT67F488/HT67F489
TinyPowerTM A/D 8-Bit Flash MCU with LCD & EEPROM
Bit 2~0TnRP2~TnRP0: TMn CCRP 3-bit register, compared with the TMn Counter bit 9~bit
7 Comparator P Match Period
000: 1024 TMn clocks
001: 128 TMn clocks
010: 256 TMn clocks
011: 384 TMn clocks
100: 512 TMn clocks
101: 640 TMn clocks
110: 768 TMn clocks
111: 896 TMn clocks
These three bits are used to setup the value on the internal CCRP 3-bit register, which
are then compared with the internal counter’s highest three bits. The result of this
comparison can be selected to clear the internal counter if the TnCCLR bit is set to
zero. Setting the TnCCLR bit to zero ensures that a compare match with the CCRP
values will reset the internal counter. As the CCRP bits are only compared with the
highest three counter bits, the compare values exist in 128 clock cycle multiples.
Clearing all three bits to zero is in effect allowing the counter to overflow at its
maximum value.
TMnC1 Register
Rev. 1.50
Bit
7
6
5
4
3
2
1
0
Name
TnM1
TnM0
TnIO1
TnIO0
TnOC
TnPOL
TnDPX
TnCCLR
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
0
0
0
0
0
0
0
Bit 7~6
TnM1, TnM0: Select TMn Operating Mode
00: Compare Match Output Mode
01: Undefined
10: PWM Mode
11: Timer/Counter Mode
These bits setup the required operating mode for the TM. To ensure reliable operation
the TM should be switched off before any changes are made to the TnM1 and TnM0
bits. In the Timer/Counter Mode, the TM output pin control must be disabled.
Bit 5~4
TnIO1, TnIO0: Select TPn 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 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.
81
August 13, 2014
TinyPower
TM
HT67F488/HT67F489
A/D 8-Bit Flash MCU with LCD & EEPROM
In the Compare Match Output Mode, the TnIO1 and TnIO0 bits determine how the
TM output pin changes state when a compare match occurs from the Comparator A.
The TM output pin can be setup to switch high, switch low or to toggle its present
state when a compare match occurs from the Comparator A. When the bits are both
zero, then no change will take place on the output. The initial value of the TM output
pin should be setup using the TnOC bit in the TMnC1 register. Note that the output
level requested by the TnIO1 and TnIO0 bits must be different from the initial value
setup using the TnOC bit otherwise no change will occur on the TM output pin when
a compare match occurs. After the TM output pin changes state, it can be reset to its
initial level by changing the level of the TnON bit from low to high.
In the PWM Mode, the TnIO1 and TnIO0 bits determine how the TM output pin
changes state when a certain compare match condition occurs. The PWM output
function is modified by changing these two bits. It is necessary to only change the
values of the TnIO1 and TnIO0 bits only after the TMn has been switched off.
Unpredictable PWM outputs will occur if the TnIO1 and TnIO0 bits are changed when
the TM is running.
Bit 3TnOC: TPn Output control bit
Compare Match Output Mode
0: Initial low
1: Initial high
PWM Mode
0: Active low
1: Active high
This is the output control bit for the TM output pin. Its operation depends upon
whether TM is being used in the Compare Match Output Mode or in the PWM Mode.
It has no effect if the TM is in the Timer/Counter Mode. In the Compare Match Output
Mode it determines the logic level of the TM output pin before a compare match
occurs. In the PWM Mode it determines if the PWM signal is active high or active
low.
Bit 2TnPOL: TPn Output polarity Control
0: Non-invert
1: Invert
This bit controls the polarity of the TPn output pin. When the bit is set high the TM
output pin will be inverted and not inverted when the bit is zero. It has no effect if the
TM is in the Timer/Counter Mode.
Bit 1TnDPX: TMn PWM period/duty Control
0: CCRP - period; CCRA - duty
1: CCRP - duty; CCRA - period
This bit, determines which of the CCRA and CCRP registers are used for period and
duty control of the PWM waveform.
Bit 0TnCCLR: Select TMn Counter clear condition
0: TMn Comparatror P match
1: TMn Comparatror A match
This bit is used to select the method which clears the counter. Remember that the
Compact TM contains two comparators, Comparator A and Comparator P, either of
which can be selected to clear the internal counter. With the TnCCLR bit set high,
the counter will be cleared when a compare match occurs from the Comparator A.
When the bit is low, the counter will be cleared when a compare match occurs from
the Comparator P or with a counter overflow. A counter overflow clearing method can
only be implemented if the CCRP bits are all cleared to zero. The TnCCLR bit is not
used in the PWM Mode.
Rev. 1.50
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HT67F488/HT67F489
TinyPowerTM A/D 8-Bit Flash MCU with LCD & 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 7~0D7~D0: TMn Counter Low Byte Register bit 7 ~ bit 0
TMn 10-bit Counter bit 7 ~ bit 0
TMnDH Register
Bit
7
6
5
4
3
2
1
0
Name
—
—
—
—
—
—
D9
D8
R/W
—
—
—
—
—
—
R
R
POR
—
—
—
—
—
—
0
0
2
1
0
Bit 7~2
Unimplemented, read as “0”
Bit 1~0D9~D8: TMn Counter High Byte Register bit 1 ~ bit 0
TMn 10-bit Counter bit 9 ~ bit 8
TMnAL Register
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
1
0
Bit 7~0D7~D0: TMn CCRA Low Byte Register bit 7 ~ bit 0
TMn 10-bit CCRA bit 7 ~ bit 0
TMnAH Register
Bit
7
6
5
4
3
2
Name
—
—
—
—
—
—
D9
D8
R/W
—
—
—
—
—
—
R/W
R/W
POR
—
—
—
—
—
—
0
0
Bit 7~2
Unimplemented, read as “0”
Bit 1~0D9~D8: TMn CCRA High Byte Register bit 1 ~ bit 0
TMn 10-bit CCRA bit 9 ~ bit 8
Rev. 1.50
83
August 13, 2014
TinyPower
TM
HT67F488/HT67F489
A/D 8-Bit Flash MCU with LCD & EEPROM
Compact Type TM Operating Modes
The Compact Type TM can operate in one of three operating modes, Compare Match Output Mode,
PWM Mode or Timer/Counter Mode. The operating mode is selected using the TnM1 and TnM0
bits in the TMnC1 register.
Compare Match Output Mode
To select this mode, bits TnM1 and TnM0 in the TMnC1 register, should be set to 00 respectively.
In this mode once the counter is enabled and running it can be cleared by three methods. These are
a counter overflow, a compare match from Comparator A and a compare match from Comparator P.
When the TnCCLR bit is low, there are two ways in which the counter can be cleared. One is when
a compare match occurs from Comparator P, the other is when the CCRP bits are all zero which
allows the counter to overflow. Here both TnAF and TnPF interrupt request flags for the Comparator
A and Comparator P respectively, will both be generated.
If the TnCCLR bit in the TMnC1 register is high then the counter will be cleared when a compare
match occurs from Comparator A. However, here only the TnAF interrupt request flag will be
generated even if the value of the CCRP bits is less than that of the CCRA registers. Therefore when
TnCCLR is high no TnPF interrupt request flag will be generated. If the CCRA bits are all zero, the
counter will overflow when its reaches its maximum 10-bit, 3FF Hex, value, however here the TnAF
interrupt request flag will not be generated.
As the name of the mode suggests, after a comparison is made, the TM output pin will change
state. The TM output pin condition however only changes state when a TnAF interrupt request flag
is generated after a compare match occurs from Comparator A. The TnPF interrupt request flag,
generated from a compare match occurs from Comparator P, will have no effect on the TM output
pin. The way in which the TM output pin changes state are determined by the condition of the
TnIO1 and TnIO0 bits in the TMnC1 register. The TM output pin can be selected using the TnIO1
and TnIO0 bits to go high, to go low or to toggle from its present condition when a compare match
occurs from Comparator A. The initial condition of the TM output pin, which is setup after the
TnON bit changes from low to high, is setup using the TnOC bit. Note that if the TnIO1 and TnIO0
bits are zero then no pin change will take place.
Rev. 1.50
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August 13, 2014
HT67F488/HT67F489
TinyPowerTM A/D 8-Bit Flash MCU with LCD & EEPROM
Co�nter Val�e
Co�nter overflow
CCRP=0
0x�FF
TnCCLR = 0; TnM [1:0] = 00
CCRP > 0
Co�nter cleared by CCRP val�e
CCRP > 0
Co�nter
Restart
Res�me
CCRP
Pa�se
CCR�
Stop
Time
TnON
TnP�U
TnPOL
CCRP Int.
Fla� TnPF
CCR� Int.
Fla� Tn�F
TM O/P Pin
O�tp�t pin set to
initial Level Low
if TnOC=0
O�tp�t not affected by Tn�F
fla�. Remains Hi�h �ntil reset
by TnON bit
O�tp�t To��le with
Tn�F fla�
Here TnIO [1:0] = 11
To��le O�tp�t select
Note TnIO [1:0] = 10
�ctive Hi�h O�tp�t select
O�tp�t Inverts
when TnPOL is hi�h
O�tp�t Pin
Reset to Initial val�e
O�tp�t controlled by
other pin-shared f�nction
Compare Match Output Mode - TnCCLR = 0 (n=1~3)
Note: 1. With TnCCLR=0, a Comparator P match will clear the counter
2. The TM output pin is controlled only by the TnAF flag
3. The output pin is reset to its initial state by a TnON bit rising edge
Rev. 1.50
85
August 13, 2014
TinyPower
TM
HT67F488/HT67F489
A/D 8-Bit Flash MCU with LCD & EEPROM
Co�nter Val�e
TnCCLR = 1; TnM [1:0] = 00
CCR� = 0
Co�nter overflow
CCR� > 0 Co�nter cleared by CCR� val�e
0x�FF
CCR�=0
Res�me
CCR�
Pa�se
Stop
Co�nter Restart
CCRP
Time
TnON
TnP�U
TnPOL
No Tn�F fla�
�enerated on
CCR� overflow
CCR� Int.
Fla� Tn�F
CCRP Int.
Fla� TnPF
TnPF not
�enerated
O�tp�t does
not chan�e
TM O/P Pin
O�tp�t pin set to
initial Level Low
if TnOC=0
O�tp�t not affected by
Tn�F fla�. Remains Hi�h
�ntil reset by TnON bit
O�tp�t To��le with
Tn�F fla�
Here TnIO [1:0] = 11
To��le O�tp�t select
Note TnIO [1:0] = 10
�ctive Hi�h O�tp�t select
O�tp�t Inverts
when TnPOL is hi�h
O�tp�t Pin
Reset to Initial val�e
O�tp�t controlled by
other pin-shared f�nction
Compare Match Output Mode - TnCCLR = 1 (n=1~3)
Note: 1. With TnCCLR=1, a Comparator A match will clear the counter
2. The TM output pin is controlled only by the TnAF flag
3. The output pin is reset to its initial state by a TnON bit rising edge
4. The TnPF flag is not generated when TnCCLR=1
Rev. 1.50
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HT67F488/HT67F489
TinyPowerTM A/D 8-Bit Flash MCU with LCD & EEPROM
Timer/Counter Mode
To select this mode, bits TnM1 and TnM0 in the TMnC1 register should be set to 11 respectively.
The Timer/Counter Mode operates in an identical way to the Compare Match Output Mode
generating the same interrupt flags. The exception is that in the Timer/Counter Mode the TM output
pin is not used. Therefore the above description and Timing Diagrams for the Compare Match
Output Mode can be used to understand its function. As the TM output pin is not used in this mode,
the pin can be used as a normal I/O pin or other pin-shared function.
PWM Output Mode
To select this mode, bits TnM1 and TnM0 in the TMnC1 register should be set to 10 respectively.
The PWM function within the TM is useful for applications which require functions such as motor
control, heating control, illumination control etc. By providing a signal of fixed frequency but
of varying duty cycle on the TM output pin, a square wave AC waveform can be generated with
varying equivalent DC RMS values.
As both the period and duty cycle of the PWM waveform can be controlled, the choice of generated
waveform is extremely flexible. In the PWM mode, the TnCCLR bit has no effect on the PWM
operation. Both of the CCRA and CCRP registers are used to generate the PWM waveform, one
register is used to clear the internal counter and thus control the PWM waveform frequency, while
the other one is used to control the duty cycle. Which register is used to control either frequency
or duty cycle is determined using the TnDPX bit in the TMnC1 register. The PWM waveform
frequency and duty cycle can therefore be controlled by the values in the CCRA and CCRP registers.
An interrupt flag, one for each of the CCRA and CCRP, will be generated when a compare match
occurs from either Comparator A or Comparator P. The TnOC bit in the TMnC1 register is used to
select the required polarity of the PWM waveform while the two TnIO1 and TnIO0 bits are used to
enable the PWM output or to force the TM output pin to a fixed high or low level. The TnPOL bit is
used to reverse the polarity of the PWM output waveform.
• CTM, PWM Mode, Edge-aligned Mode, TnDPX=0
CCRP
001b
010b
011b
100b
101b
110b
111b
000b
Period
128
256
384
512
640
768
896
1024
Duty
CCRA
If fSYS = 8MHz, TM clock source is fSYS/4, CCRP = 100b and CCRA = 128,
The CTM PWM output frequency = (fSYS/4)/512 = fSYS/2048 = 3.90625kHz, duty = 128/512 = 25%.
If the Duty value defined by the CCRA register is equal to or greater than the Period value, then the
PWM output duty is 100%.
• CTM, PWM Mode, Edge-aligned Mode, TnDPX=1
CCRP
001b
010b
011b
100b
128
256
384
512
Period
Duty
101b
110b
111b
000b
768
896
1024
CCRA
640
The PWM output period is determined by the CCRA register value together with the TM clock
while the PWM duty cycle is defined by the CCRP register value.
Rev. 1.50
87
August 13, 2014
TinyPower
TM
Co�nter Val�e
HT67F488/HT67F489
A/D 8-Bit Flash MCU with LCD & EEPROM
TnDPX = 0; TnM [1:0] = 10
Co�nter cleared
by CCRP
Co�nter Reset when
TnON ret�rns hi�h
CCRP
Pa�se Res�me
CCR�
Co�nter Stop if
TnON bit low
Time
TnON
TnP�U
TnPOL
CCR� Int.
Fla� Tn�F
CCRP Int.
Fla� TnPF
TM O/P Pin
(TnOC=1)
TM O/P Pin
(TnOC=0)
PWM D�ty Cycle
set by CCR�
PWM Period
set by CCRP
PWM res�mes
operation
O�tp�t controlled by
O�tp�t Inverts
other pin-shared f�nction
when TnPOL = 1
PWM Mode - TnDPX = 0 (n=1~3)
Note: 1. Here TnDPX=0 – Counter cleared by CCRP
2. A counter clear sets the PWM Period
3. The internal PWM function continues even when TnIO [1:0] = 00 or 01
4. The TnCCLR bit has no influence on PWM operation
Rev. 1.50
88
August 13, 2014
HT67F488/HT67F489
TinyPowerTM A/D 8-Bit Flash MCU with LCD & EEPROM
Co�nter Val�e
TnDPX = 1; TnM [1:0] = 10
Co�nter cleared
by CCR�
Co�nter Reset when
TnON ret�rns hi�h
CCR�
Pa�se Res�me
CCRP
Co�nter Stop if
TnON bit low
Time
TnON
TnP�U
TnPOL
CCRP Int.
Fla� TnPF
CCR� Int.
Fla� Tn�F
TM O/P Pin
(TnOC=1)
TM O/P Pin
(TnOC=0)
PWM D�ty Cycle
set by CCRP
PWM Period
set by CCR�
PWM res�mes
operation
O�tp�t controlled by
O�tp�t Inverts
other pin-shared f�nction
when TnPOL = 1
PWM Mode - TnDPX = 1 (n=1~3)
Note: 1. Here TnDPX = 1 – Counter cleared by CCRA
2. A counter clear sets the PWM Period
3. The internal PWM function continues even when TnIO [1:0] = 00 or 01
4. The TnCCLR bit has no influence on PWM operation
Rev. 1.50
89
August 13, 2014
TinyPower
TM
HT67F488/HT67F489
A/D 8-Bit Flash MCU with LCD & EEPROM
Analog to Digital Converter – ADC
The need to interface to real world analog signals is a common requirement for many electronic
systems. However, to properly process these signals by a microcontroller, they must first be
converted into digital signals by A/D converters. By integrating the A/D conversion electronic
circuitry into the microcontroller, the need for external components is reduced significantly with the
corresponding follow-on benefits of lower costs and reduced component space requirements.
A/D Overview
The devices contain 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.
Input Channels
A/D Channel Select Bits
Input Pins
10
ACS4, ACS3~ACS0
AN0~AN9
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.
Rev. 1.50
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HT67F488/HT67F489
TinyPowerTM A/D 8-Bit Flash MCU with LCD & EEPROM
Bit
Register
Name
7
6
5
4
ADRL(ADRFS=0)
D3
D2
D1
D0
—
—
—
—
ADRL(ADRFS=1)
D7
D6
D5
D4
D3
D2
D1
D0
ADRH(ADRFS=0)
D11
D10
D9
D8
D7
D6
D5
D4
ADRH(ADRFS=1)
—
—
—
—
D11
D10
D9
D8
ADCR0
START
EOCB
ADOFF
ADRFS
ACS3
ACS2
ACS1
ACS0
ADCR1
ACS4
VBGEN
—
VREFS
—
ADCK2
ADCK1
ADCK0
ACERL
ACE7
ACE6
ACE5
ACE4
ACE3
ACE2
ACE1
ACE0
ACERH
—
—
—
—
—
—
ACE9
ACE8
3
2
1
0
A/D Converter Register List
A/D Converter Data Registers – ADRL, ADRH
The devices, which have an internal 12-bit A/D converter, require two data registers, 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
D9
D8
D7
D6
D5
D4
D3
D2
D1
D0
0
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, ACERH
To control the function and operation of the A/D converter, three control registers known as
ADCR0, ADCR1, ACERL and ACERH are provided. These 8-bit registers define functions such
as the selection of which analog channel is connected to the internal A/D converter, the digitised
data format, the A/D clock source as well as controlling the start function and monitoring the A/D
converter end of conversion status. The ACS3~ACS0 bits in the ADCR0 register and the ACS4 bit
in the ADCR1 register define the ADC input channel number. As the device contains 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~ACS0 bits to determine which analog channel input pin
or internal VBG is actually connected to the internal A/D converter.
The ACERH and ACERL control registers contain the ACE9~ACE0 bits which determine which
pins on PB and PE Ports are used as analog inputs for the A/D converter input and which pins are
not to be used as the A/D converter input. Setting the corresponding bit high will select the A/D
input function, clearing the bit to zero will select either the I/O or other pin-shared function. When
the pin is selected to be an A/D input, its original function whether it is an I/O or other pin-shared
function will be removed. In addition, any internal pull-high resistors connected to these pins will be
automatically removed if the pin is selected to be an A/D input.
Rev. 1.50
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TinyPower
TM
HT67F488/HT67F489
A/D 8-Bit Flash MCU with LCD & EEPROM
ADCR0 Register
Bit
7
6
5
4
3
2
1
0
Name
START
EOCB
ADOFF
ADRFS
ACS3
ACS2
ACS1
ACS0
R/W
R/W
R
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
1
1
0
0
0
0
0
Bit 7START: Start the A/D conversion
0→1→0: Start
0→1: Reset the A/D converter and set EOCB to “1”
This bit is used to initiate an A/D conversion process. The bit is normally low but if set
high and then cleared low again, the A/D converter will initiate a conversion process.
When the bit is set high the A/D converter will be reset.
Bit 6EOCB: End of A/D conversion flag
0: A/D conversion ended
1: A/D conversion in progress
This read only flag is used to indicate when an A/D conversion process has completed.
When the conversion process is running, the bit will be high.
Bit 5ADOFF: ADC module power on/off control bit
0: ADC module power on
1: ADC module power off
This bit controls the power to the A/D internal function. This bit should be cleared
to zero to enable the A/D converter. If the bit is set high then the A/D converter will
be switched off reducing the 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: A/D data format control bit
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 3~0ACS3~ACS0: Select A/D channel (when ACS4 is “0”)
0000: AN0
0001: AN1
0010: AN2
0011: AN3
0100: AN4
0101: AN5
0110: AN6
0111: AN7
1000: AN8
1001~1111: AN9
These are the A/D channel select control bits. As there is only one internal hardware A/
D converter each of the ten A/D inputs must be routed to the internal converter using
these bits. If the ACS4 bit is set high, then the internal Bandgap VBG will be routed to
the A/D Converter.
Rev. 1.50
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HT67F488/HT67F489
TinyPowerTM A/D 8-Bit Flash MCU with LCD & EEPROM
ADCR1 Register
Bit
7
6
5
4
3
2
1
0
Name
ACS4
VBGEN
—
VREFS
—
ADCK2
ADCK1
ADCK0
R/W
R/W
R/W
—
R/W
—
R/W
R/W
R/W
POR
0
0
—
0
—
0
0
0
Bit 7ACS4: Select internal VBG as ADC input control
0: Disable
1: Enable
This bit enables VBG to be connected to the A/D converter. The VBGEN bit must
first have been set to enable the bandgap circuit VBG voltage to be used by the A/D
converter. When the ACS4 bit is set high, the bandgap VBG voltage will be routed to
the A/D converter and the other A/D input channels disconnected.
Bit 6VBGEN: Internal VBG 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 VBG can be used by the A/D converter. If
VBG 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
VBG 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: Selecte 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. When the A/D converter reference voltage is supplied on the external VREF pin
which is pin-shared with other functions, all of the pin-shared functions except VREF
on this pin are disabled.
Bit 3
Unimplemented, read as “0”
Bit 2~0ADCK2~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.
Rev. 1.50
93
August 13, 2014
TinyPower
TM
HT67F488/HT67F489
A/D 8-Bit Flash MCU with LCD & EEPROM
Bandgap reference voltage on/off true table:
ACS4
VBGEN
LVR/LVD
VBG
Bandgap Reference Voltage
x
x
0
Enable
Off to GND
On
0
Disable
Off to GND
x
Off
1
x
On
On
x: Don’t care
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 PB4 is A/D input or not
0: Not A/D input
1: A/D input, AN7
Bit 6ACE6: Define PE6 is A/D input or not
0: Not A/D input
1: A/D input, AN6
Bit 5ACE5: Define PE5 is A/D input or not
0: Not A/D input
1: A/D input, AN5
Bit 4ACE4: Define PE4 is A/D input or not
0: Not A/D input
1: A/D input, AN4
Bit 3ACE3: Define PB3 is A/D input or not
0: Not A/D input
1: A/D input, AN3
Bit 2ACE2: Define PB2 is A/D input or not
0: Not A/D input
1: A/D input, AN2
Bit 1ACE1: Define PB1 is A/D input or not
0: Not A/D input
1: A/D input, AN1
Bit 0ACE0: Define PB0 is A/D input or not
0: Not A/D input
1: A/D input, AN0
Rev. 1.50
94
August 13, 2014
HT67F488/HT67F489
TinyPowerTM A/D 8-Bit Flash MCU with LCD & EEPROM
ACERH Register
Bit
7
6
5
4
3
2
1
0
Name
—
—
—
—
—
—
ACE9
ACE8
R/W
—
—
—
—
—
—
R/W
R/W
POR
—
—
—
—
—
—
1
1
Bit 7~2
Unimplemented, read as “0”
Bit 1ACE9: Define PB5 is A/D input or not
0: Not A/D input
1: A/D input, AN9
Bit 0ACE8: Define PE7 is A/D input or not
0: Not A/D input
1: A/D input, AN8
A/D Operation
The START bit in the ADCR0 register is used to start and reset the A/D converter. When the
microcontroller sets this bit from low to high and then low again, an analog to digital conversion
cycle will be initiated. When the START bit is brought from low to high but not low again, the
EOCB bit in the ADCR0 register will be set high and the analog to digital converter will be reset.
It is the START bit that is used to control the overall start operation of the internal analog to digital
converter.
The EOCB bit in the ADCR0 register is used to indicate when the analog to digital conversion
process is complete. This bit will be automatically set to “0” by the microcontroller after a
conversion cycle has ended. In addition, the corresponding A/D interrupt request flag will be set
in the interrupt control register, and if the interrupts are enabled, an appropriate internal interrupt
signal will be generated. This A/D internal interrupt signal will direct the program flow to the
associated A/D internal interrupt address for processing. If the A/D internal interrupt is disabled,
the microcontroller can be used to poll the EOCB bit in the ADCR0 register to check whether it has
been cleared as an alternative method of detecting the end of an A/D conversion cycle.
The clock source for the A/D converter, which originates from the system clock fSYS, can be chosen
to be either fSYS or a subdivided version of fSYS The division ratio value is determined by the
ADCK2~ADCK0 bits in the ADCR1 register.
Although the A/D clock source is determined by the system clock fSYS, and by bits ADCK2~ADCK0,
there are some limitations on the A/D clock source speed range that can be selected. As the
recommended range of permissible A/D clock period, tADCK, is from 0.5μs to 10μs, care must be
taken for selected system clock frequencies. For example, if the system clock operates at a frequency
of 4MHz, the ADCK2~ADCK0 bits should not be set to 000B or 110B. Doing so will give A/D
clock periods that are less than the minimum A/D clock period or greater than the maximum 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.
Rev. 1.50
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TinyPower
TM
HT67F488/HT67F489
A/D 8-Bit Flash MCU with LCD & EEPROM
A/D Clock Period (tADCK)
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
fSYS
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. When the
ADOFF bit is cleared to zero to power on the A/D converter internal circuitry a certain delay, as
indicated in the timing diagram, must be allowed before an A/D conversion is initiated. Even if no
pins are selected for use as A/D inputs by clearing the ACE9~ACE0 bits in the ACERH and 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 PB and PE I/O pins as well as other
functions. The ACE9~ACE0 bits in the ACERH and ACERL registers, determine whether the
input pins are setup as A/D converter analog inputs or whether they have other functions. If the
ACE9~ACE0 bits for its corresponding pin is set high then the pins 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
PBC or PEC port control register to enable the A/D input as when the ACE9~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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TinyPowerTM A/D 8-Bit Flash MCU with LCD & EEPROM
     
   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~ACS0 bits which are also contained in the ADCR1 and ADCR0 registers.
• Step 4
Select which pins are to be used as A/D inputs and configure them by correctly programming the
ACE9~ACE0 bits in the ACERH and ACERL registers.
• Step 5
If the interrupts are to be used, the interrupt control registers must be correctly configured to
ensure the A/D converter interrupt function is active. The master interrupt control bit, EMI, and
the A/D converter interrupt bit, ADE, must both be set high to do this.
• Step 6
The analog to digital conversion process can now be initialised by setting the START bit in
the ADCR0 register from low to high and then low again. Note that this bit should have been
originally cleared to zero.
• Step 7
To check when the analog to digital conversion process is complete, the EOCB bit in the ADCR0
register can be polled. The conversion process is complete when this bit goes low. When this
occurs the A/D data registers ADRL and ADRH can be read to obtain the conversion value. As an
alternative method, if the interrupts are enabled and the stack is not full, the program can wait for
an A/D interrupt to occur.
Note: When checking for the end of the conversion process, if the method of polling the EOCB bit
in the ADCR0 register is used, the interrupt enable step above can be omitted.
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.
Rev. 1.50
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August 13, 2014
TinyPower
TM
HT67F488/HT67F489
A/D 8-Bit Flash MCU with LCD & EEPROM
�DOFF
tON�ST
�DC mod�le ON
off
on
off
�/D samplin� time
�/D samplin� time
t�DCS
ST�RT
on
t�DCS
EOCB
�CS�~�CS0
00011B
Power-on
Reset
00010B
00000B
Reset �/D
conversion
1. Define port confi��ration
�. Select analo� channel
Start of �/D conversion
Reset �/D
conversion
Start of �/D
conversion
End of �/D
conversion
t�DC
�/D conversion time
00001B
Start of �/D
conversion
Reset �/D
conversion
End of �/D
conversion
t�DC
�/D conversion time
A/D Conversion Timing
Programming Considerations
During microcontroller operations where the A/D converter is not being used, the A/D internal
circuitry can be switched off to reduce power consumption, by setting bit ADOFF high in the
ADCR0 register. When this happens, the internal A/D converter circuits will not consume power
irrespective of what analog voltage is applied to their input lines. If the A/D converter input lines are
used as normal I/Os, then care must be taken as if the input voltage is not at a valid logic level, then
this may lead to some increase in power consumption.
A/D Transfer Function
As the devices contain a 12-bit A/D converter, its full-scale converted digitised value is equal to
FFFH. Since the full-scale analog input value is equal to the VDD or VREF voltage, this gives a single
bit analog input value of VDD or VREF divided by 4096.
1 LSB = (VDD or VREF) ÷ 4096
The A/D Converter input voltage value can be calculated using the following equation:
A/D input voltage = A/D output digital value × (VDD or VREF) ÷ 4096
The diagram shows the ideal transfer function between the analog input value and the digitised
output value for the A/D converter. Except for the digitised zero value, the subsequent digitised
values will change at a point 0.5 LSB below where they would change without the offset, and the
last full scale digitised value will change at a point 1.5 LSB below the VDD or VREF level.
Rev. 1.50
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TinyPowerTM A/D 8-Bit Flash MCU with LCD & EEPROM
    
 
      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;
mov a, 03H
mov ADCR1, a ;
clr ADOFF
mov a, 0Fh ;
mov ACERL, a
mova,00h
mov ACERH,a
mov a, 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. 1.50
disable ADC interrupt
select fSYS/8 as A/D clock and switch off VBG
setup ACERL to configure pins AN0~AN3
enable and connect AN0 channel to A/D converter
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
99
August 13, 2014
TinyPower
TM
HT67F488/HT67F489
A/D 8-Bit Flash MCU with LCD & EEPROM
Example: using the interrupt method to detect the end of conversion
clr
ADE;
mov a, 03H
mov ADCR1, a ;
clr ADOFF
mov a, 0Fh ;
mov ACERL, a
mova,00h
mov ACERH,a
mov a, 00h
mov ADCR0, a ;
:
:
Start_conversion:
clr START
set START ;
clr START ;
clr ADF ;
set
ADE;
set EMI ;
:
:
;
ADC_:
mov acc_stack, a ;
mov a, STATUS
mov status_stack, a ;
:
:
mov a, ADRL ;
mov adrl_buffer, a ;
mov a, ADRH ;
mov adrh_buffer, a ;
:
:
EXIT_ISR:
mov a, status_stack
mov STATUS, a ;
mov a, acc_stack ;
clr ADF ;
reti
Rev. 1.50
disable ADC interrupt
select fSYS/8 as A/D clock and switch off VBG
setup ACERL to configure pins AN0~AN3
enable and connect AN0 channel to A/D converter
reset A/D
start A/D
clear ADC interrupt request flag
enable ADC interrupt
enable global interrupt
ADC interrupt service routine
save ACC to user defined memory
save STATUS to user defined memory
read
save
read
save
low byte conversion result value
result to user defined register
high byte conversion result value
result to user defined register
restore STATUS from user defined memory
restore ACC from user defined memory
clear ADC interrupt flag
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TinyPowerTM A/D 8-Bit Flash MCU with LCD & EEPROM
LCD Display Memory
The devices provide an area of embedded data memory for LCD display. This area is located from
80H to 93H of the RAM at Sector 1. The Memory Pointer MP1H is the switch between the RAM
and the LCD display memory. When the MP1H = 01H, data written into 80H~93H will affect the
LCD display. When the MP1H is written other than 01H, any data written into 80H~93H is meant to
access the general purpose data memory.
The LCD display memory can be read and written to only by indirect addressing mode using MP1L
and MP1H. When data is written into the display data area, it is automatically read by the LCD
driver which then generates the corresponding LCD driving signals. To turn the display on or off,
a “1” or a “0” is written to the corresponding bit of the display memory, respectively. The figure
illustrates the mapping between the display memory and LCD pattern for the device.
b7
b6
b5
b4
b3
b2
b1
b0
180H
SEG1
181H
SEG2
192H
SEG18
193H
SEG19
COM7
COM6
COM5
COM4
COM3
COM2
COM1
COM0
LCD Driver Output
The output number of the device LCD driver can be 20×4 or 20×8. The LCD driver is “R” type only.
The LCD clock source is from fSUB, which can be either the LXT or LIRC oscillator.
Rev. 1.50
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TinyPower
TM
HT67F488/HT67F489
A/D 8-Bit Flash MCU with LCD & EEPROM
LCD Control Register
LCDC0 Register
Bit
7
6
5
4
3
2
1
0
Name
LCDEN
TYPE
DTYC
BIAS
—
RSEL2
RSEL1
RSEL0
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 7LCDEN: LCD enable/disable control
0: Disable
1: Enable
Note that the LCD driver and A/D converter should not be enabled simultaneously
when the LCD output and A/D channel are shared with the same pin.
Bit 6TYPE: LCD Waveform Type selection
0: Type A
1: Type B
Bit 5DTYC: Define LCD Duty
0: 1/4 Duty ( LCD COM: COM0~COM3)
1: 1/8 Duty (LCD COM: COM0~COM7)
Note: If DTYC=1, then COM4~COM7 pins will be configured as LCD COM.
If DTYC=0, then COM4~COM7 pins will be configured as I/O.
Bit 4BIAS: Define LCD Bias
0: 1/3 Bias
1: 1/4 Bias
Bit 3
Unimplemented, read as “0”
Bit 2~0RSEL2~RSEL0: Total Bias Resistor RT selection
000: 1170K
001: 225K
010: 60K
011: Quick Charging Mode, switch between 60K and 1170K.
1xx: Quick Charging Mode, switch between 60K and 225K.
Note: The bias resistor for 1/3 bias is RT/3, 1/4 bias is RT/4.
The devices provide low power quick charging mode for LCD display. In quick charging mode,
the LCD will provide LCD bias current by RT=60K, at beginning of LCD display refreshes (i.e
the moment on LCD COM changes). After quick charging time, the bias resistor will change to
225K/1170K.
Rev. 1.50
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TinyPowerTM A/D 8-Bit Flash MCU with LCD & EEPROM
LCDC1 Register
Bit
7
6
5
4
3
2
1
0
Name
QCT2
QCT1
QCT0
—
VLCD3
VLCD2
VLCD1
VLCD0
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 7QCT2~QCT0: Quick charging time selection
000: 1×tSUB
001: 2×tSUB
010: 3×tSUB
011: 4×tSUB
100: 5×tSUB
101: 6×tSUB
110: 7×tSUB
111: 8×tSUB
tSUB = 1/fSUB
Bit 6 ~ 4
Unimplemented, read as "0"
Bit 3 ~ 0VLCD3~VLCD0: VLCD selection
0000: 8/16×VDD
0001: 9/16×VDD
0010: 10/16×VDD
0011: 11/16×VDD
0100: 12/16×VDD
0101: 13/16×VDD
0110: 14/16×VDD
0111: 15/16×VDD
1000~1111: 16/16×VDD
Rev. 1.50
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TinyPower
TM
HT67F488/HT67F489
A/D 8-Bit Flash MCU with LCD & EEPROM
SEGCR0 Register
Bit
7
6
5
4
3
2
1
0
Name
SEG7C
SEG6C
SEG5C
SEG4C
SEG3C
SEG2C
SEG1C
SEG0C
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 7SEG7C: Select SEG7 or PD7
0: SEG7
1: PD7
Bit 6SEG6C: Select SEG6 or PD6
0: SEG6
1: PD6
Bit 5SEG5C: Select SEG5 or PD5
0: SEG5
1: PD5
Bit 4SEG4C: Select SEG4 or PD4
0: SEG4
1: PD4
Bit 3SEG3C: Select SEG3 or PD3
0: SEG3
1: PD3
Bit 2SEG2C: Select SEG2 or PD2
0: SEG2
1: PD2
Bit 1SEG1C: Select SEG1 or PD1
0: SEG1
1: PD1
Bit 0SEG0C: Select SEG0 or PD0
0: SEG0
1: PD0
Rev. 1.50
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HT67F488/HT67F489
TinyPowerTM A/D 8-Bit Flash MCU with LCD & EEPROM
SEGCR1 Register
Bit
7
6
5
4
3
2
1
0
Name
SEG15C
SEG14C
SEG13C
SEG12C
SEG11C
SEG10C
SEG9C
SEG8C
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 7SEG15C: Select SEG15 or PC7
0: SEG15
1: PC7
Bit 6SEG14C: Select SEG14 or PC6
0: SEG14
1: PC6
Bit 5SEG13C: Select SEG13 or PC5
0: SEG13
1: PC5
Bit 4SEG12C: Select SEG12 or PC4
0: SEG12
1: PC4
Bit 3SEG11C: Select SEG11 or PC3
0: SEG11
1: PC3
Bit 2SEG10C: Select SEG10 or PC2
0: SEG10
1: PC2
Bit 1SEG9C: Select SEG9 or PC1
0: SEG9
1: PC1
Bit 0SEG8C: Select SEG8 or PC0
0: SEG8
1: PC0
SEGCR2 Register
Bit
7
6
5
4
3
2
1
0
Name
—
—
—
—
SEG19C
SEG18C
SEG17C
SEG16C
R/W
—
—
—
—
R/W
R/W
R/W
R/W
POR
—
—
—
—
0
0
0
0
Bit 7~4
Unimplemented, read as “0”
Bit 3SEG19C: Select SEG19 or PF7
0: SEG19
1: PF7
Bit 2SEG18C: Select SEG18 or PF6
0: SEG18
1: PF6
Bit 1SEG17C: Select SEG17 or PF5
0: SEG17
1: PF5
Bit 0SEG16C: Select SEG16 or PF4
0: SEG16
1: PF4
Rev. 1.50
105
August 13, 2014
TinyPower
TM
HT67F488/HT67F489
A/D 8-Bit Flash MCU with LCD & EEPROM
LCD Waveform
LCD Display Off Mode
COM0 ~ COM�
V�
VB
VC
VSS
�ll sen�ment o�tp�ts
V�
VB
VC
VSS
Normal Operation Mode
1 Frame
COM0
V�
VB
VC
VSS
COM1
V�
VB
VC
VSS
COM�
V�
VB
VC
VSS
COM�
V�
VB
VC
VSS
�ll se�ments are OFF
V�
VB
VC
VSS
COM0 side se�ments are ON
V�
VB
VC
VSS
COM1 side se�ments are ON
V�
VB
VC
VSS
COM� side se�ments are ON
V�
VB
VC
VSS
COM� side se�ments are ON
V�
VB
VC
VSS
COM0�1 side se�ments are ON
V�
VB
VC
VSS
COM0�� side se�ments are ON
V�
VB
VC
VSS
COM0�� side se�ments are ON
V�
VB
VC
VSS
(other combinations are omitted)
V�
VB
VC
VSS
�ll sen�ments are ON
LCD Driver Output – Type A - 1/4 Duty, 1/3 Bias
Note: VA=VLCD, VB=VLCD×2/3 and VC=VLCD×1/3.
Rev. 1.50
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TinyPowerTM A/D 8-Bit Flash MCU with LCD & EEPROM
LCD Display Off Mode
COM0 ~ COM�
V�
VB
VC
VSS
�ll sen�ment o�tp�ts
V�
VB
VC
VSS
Normal Operation Mode
1 Frame
COM0
V�
VB
VC
VSS
COM1
V�
VB
VC
VSS
COM�
V�
VB
VC
VSS
COM�
V�
VB
VC
VSS
�ll se�ments are OFF
V�
VB
VC
VSS
COM0 side se�ments are ON
V�
VB
VC
VSS
COM1 side se�ments are ON
V�
VB
VC
VSS
COM� side se�ments are ON
V�
VB
VC
VSS
COM� side se�ments are ON
V�
VB
VC
VSS
COM0�1 side se�ments are ON
V�
VB
VC
VSS
COM0�� side se�ments are ON
V�
VB
VC
VSS
COM0�� side se�ments are ON
V�
VB
VC
VSS
(other combinations are omitted)
V�
VB
VC
VSS
�ll sen�ments are ON
LCD Driver Output – Type B - 1/4 Duty, 1/3 Bias
Note: VA=VLCD, VB=VLCD×2/3 and VC=VLCD×1/3.
Rev. 1.50
107
August 13, 2014
TinyPower
TM
HT67F488/HT67F489
A/D 8-Bit Flash MCU with LCD & EEPROM
tLCD
LCD Se�ment
LCD Se�ment
VLCD
VLCD
VLCD x �/�
VLCD x �/�
COM0 VLCD x �/�
COM0 VLCD x �/�
VLCD x 1/�
VLCD x 1/�
VSS
VSS
VLCD
VLCD
VLCD x �/�
VLCD x �/�
COM1 VLCD x �/�
COM1 VLCD x �/�
VLCD x 1/�
VLCD x 1/�
VSS
VSS
VLCD
VLCD
VLCD x �/�
VLCD x �/�
COM� VLCD x �/�
COM� VLCD x �/�
VLCD x 1/�
VLCD x 1/�
VSS
VSS
VLCD
VLCD
VLCD x �/�
VLCD x �/�
COM� VLCD x �/�
COM� VLCD x �/�
VLCD x 1/�
VLCD x 1/�
VSS
VSS
VLCD
VLCD
VLCD x �/�
VLCD x �/�
COM� VLCD x �/�
COM� VLCD x �/�
VLCD x 1/�
VLCD x 1/�
VSS
VSS
VLCD
VLCD
VLCD x �/�
VLCD x �/�
COM5 VLCD x �/�
COM5 VLCD x �/�
VLCD x 1/�
VLCD x 1/�
VSS
VSS
VLCD
VLCD
VLCD x �/�
VLCD x �/�
COM6 VLCD x �/�
COM6 VLCD x �/�
VLCD x 1/�
VLCD x 1/�
VSS
VSS
VLCD
VLCD
VLCD x �/�
VLCD x �/�
COM7 VLCD x �/�
COM7 VLCD x �/�
VLCD x 1/�
VLCD x 1/�
VSS
VSS
VLCD
VLCD
VLCD x �/�
VLCD x �/�
SEG n VLCD x �/�
SEG n VLCD x �/�
VLCD x 1/�
VLCD x 1/�
VSS
VSS
VLCD
VLCD
VLCD x �/�
VLCD x �/�
SEG n+1 VLCD x �/�
SEG n+1 VLCD x �/�
VLCD x 1/�
VLCD x 1/�
VSS
VSS
VLCD
VLCD
VLCD x �/�
VLCD x �/�
SEG n+� VLCD x �/�
SEG n+� VLCD x �/�
VLCD x 1/�
VLCD x 1/�
VSS
VSS
VLCD
VLCD
VLCD x �/�
VLCD x �/�
SEG n+� VLCD x �/�
SEG n+� VLCD x �/�
VLCD x 1/�
VLCD x 1/�
VSS
VSS
State1
State1
(on)
(on)
State�
State�
(off)
(off)
LCD Driver Output – Type A - 1/8 Duty, 1/4 Bias
Rev. 1.50
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TinyPowerTM A/D 8-Bit Flash MCU with LCD & EEPROM
LED Driver
The devices contain an LED driver function offering high current output drive capability which can
be used to drive external LEDs.
LED Driver Operation
The various I/O pins of devices have a capability of providing LED high current drive outputs, as
shown in the accompanying table.
Device
LED Drive Pins
HT67F488
HT67F489
PD0~PD7 (high source current)
PE0~PE7 (high sink current)
LED Driver Register
IOHR0 Register
Bit
7
6
5
4
3
2
1
0
Name
IOHS31
IOHS30
IOHS21
IOHS20
IOHS11
IOHS10
IOHS01
IOHS00
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
IOHR1 Register
Bit
7
6
5
4
3
2
1
0
Name
IOHS71
IOHS70
IOHS61
IOHS60
IOHS51
IOHS50
IOHS41
IOHS40
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
IOHSn[1:0]: IOH capacity selection for PDn (n=0~7)
00: Fullly source driving capacity of GPIO
01: 1/3 source driving capacity of GPIO
10: 1/4 source driving capacity of GPIO
11: 1/6 source driving capacity of GPIO
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TinyPower
TM
HT67F488/HT67F489
A/D 8-Bit Flash MCU with LCD & EEPROM
UART Interface
The device contains an integrated full-duplex asynchronous serial communications UART interface
that enables communication with external devices that contain a serial interface. The UART function
has many features and can transmit and receive data serially by transferring a frame of data with
eight or nine data bits per transmission as well as being able to detect errors when the data is
overwritten or incorrectly framed. The UART function possesses its own internal interrupt which
can be used to indicate when a reception occurs or when a transmission terminates.
The integrated UART function contains the following features:
• Full-duplex, Universal Asynchronous Receiver and Transmitter (UART) communication
• 8 or 9 bits character length
• Even, odd or no parity options
• One or two stop bits
• Baud rate generator with 8-bit prescaler
• Parity, framing, noise and overrun error detection
• Support for interrupt on address detect (last character bit=1)
• Transmitter and receiver enabled independently
• 2-byte Deep FIFO Receive Data Buffer
• Transmit and Receive Multiple Interrupt Generation Sources:
♦♦
Transmitter Empty
♦♦
Transmitter Idle
♦♦
Receiver Full
♦♦
Receiver Overrun
♦♦
Address Mode Detect
T r a n s m itte r S h ift R e g is te r
M S B
R e c e iv e r S h ift R e g is te r
L S B
T X P in
M S B
R X P in
C L K
L S B
C L K
T X R R e g is te r
B a u d R a te
G e n e ra to r
M C U
R X R
R e g is te r
B u ffe r
D a ta B u s
UART External Pin Interfacing
To communicate with an external serial interface, the internal UART has two external pins known
as TX and RX. The TX pin is the UART transmitter pin, which can be used as a general purpose
I/O or other pin-shared functional pin if the pin is not configured as a UART transmitter, which
occurs when the TXEN bit in the UCR2 control register is equal to zero. Similarly, the RX pin is the
UART receiver pin, which can also be used as a general purpose I/O or other pin-shared functional
pin, if the pin is not configured as a receiver, which occurs if the RXEN bit in the UCR2 register
is equal to zero. Along with the UARTEN bit, the TXEN and RXEN bits, if set, will automatically
setup these I/O or other pin-shared functional pins to their respective TX output and RX input
conditions and disable any pull-high resistor option which may exist on the RX pin. If the TX and
RX pins are shared with the LCD outputs and the UART interface and LCD driver both are enabled
simultaneously, the LCD driver has the priority to use the corresponding pins as LCD outputs.
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HT67F488/HT67F489
TinyPowerTM A/D 8-Bit Flash MCU with LCD & EEPROM
UART Data Transfer Scheme
The block diagram shows the overall data transfer structure arrangement for the UART. The actual
data to be transmitted from the MCU is first transferred to the TXR register by the application
program. The data will then be transferred to the Transmit Shift Register from where it will be
shifted out, LSB first, onto the TX pin at a rate controlled by the Baud Rate Generator. Only the
TXR register is mapped onto the MCU Data Memory, the Transmit Shift Register is not mapped and
is therefore inaccessible to the application program.
Data to be received by the UART is accepted on the external RX pin, from where it is shifted in,
LSB first, to the Receiver Shift Register at a rate controlled by the Baud Rate Generator. When
the shift register is full, the data will then be transferred from the shift register to the internal RXR
register, where it is buffered and can be manipulated by the application program. Only the RXR
register is mapped onto the MCU Data Memory, the Receiver Shift Register is not mapped and is
therefore inaccessible to the application program.
It should be noted that the actual register for data transmission and reception, although referred to
in the text, and in application programs, as separate TXR and RXR registers, only exists as a single
shared register in the Data Memory. This shared register known as the TXR/RXR register is used for
both data transmission and data reception.
UART Status and Control Registers
There are five control registers associated with the UART function. The USR, UCR1 and UCR2
registers control the overall function of the UART, while the BRG register controls the Baud rate.
The actual data to be transmitted and received on the serial interface is managed through the TXR/
RXR data registers.
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
TXIF
USR
PERR
NF
FERR
OERR
RIDLE
RXIF
TIDLE
UCR1
UARTEN
BNO
PREN
PRT
STOPS
TXBRK
RX8
TX8
UCR2
TXEN
RXEN
BRGH
ADDEN
WAKE
RIE
TIIE
TEIE
TXR/RXR
TXRX7
TXRX6
TXRX5
TXRX4
TXRX3
TXRX2
TXRX1
TXRX0
BRG
BRG7
BRG6
BRG5
BRG4
BRG3
BRG2
BRG1
BRG0
UART Register List
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TinyPower
TM
HT67F488/HT67F489
A/D 8-Bit Flash MCU with LCD & EEPROM
USR Register
The USR register is the status register for the UART, which can be read by the program to determine
the present status of the UART. All flags within the USR register are read only. Further explanation
on each of the flags is given below:
Bit
7
6
5
4
3
2
1
0
Name
PERR
NF
FERR
OERR
RIDLE
RXIF
TIDLE
TXIF
R/W
R
R
R
R
R
R
R
R
POR
0
0
0
0
1
0
1
1
Bit 7PERR: Parity error flag
0: No parity error is detected
1: Parity error is detected
The PERR flag is the parity error flag. When this read only flag is “0”, it indicates a
parity error has not been detected. When the flag is “1”, it indicates that the parity of
the received word is incorrect. This error flag is applicable only if Parity mode (odd or
even) is selected. The flag can also be cleared by a software sequence which involves
a read to the status register USR followed by an access to the RXR data register.
Bit 6NF: Noise flag
0: No noise is detected
1: Noise is detected
The NF flag is the noise flag. When this read only flag is "0", it indicates no noise
condition. When the flag is "1", it indicates that the UART has detected noise on the
receiver input. The NF flag is set during the same cycle as the RXIF flag but will not
be set in the case of as overrun. The NF flag can be cleared by a software sequence
which will involve a read to the status register USR followed by an access to the RXR
data register.
Bit 5FERR: Framing error flag
0: No framing error is detected
1: Framing error is detected
The FERR flag is the framing error flag. When this read only flag is “0”, it indicates
that there is no framing error. When the flag is “1”, it indicates that a framing error
has been detected for the current character. The flag can also be cleared by a software
sequence which will involve a read to the status register USR followed by an access to
the RXR data register.
Bit 4OERR: Overrun error flag
0: No overrun error is detected
1: Overrun error is detected
The OERR flag is the overrun error flag which indicates when the receiver buffer has
overflowed. When this read only flag is “0”, it indicates that there is no overrun error.
When the flag is “1”, it indicates that an overrun error occurs which will inhibit further
transfers to the RXR receive data register. The flag is cleared by a software sequence,
which is a read to the status register USR followed by an access to the RXR data
register.
Bit 3RIDLE: Receiver status
0: Data reception is in progress (data being received)
1: No data reception is in progress (receiver is idle)
The RIDLE flag is the receiver status flag. When this read only flag is “0”, it indicates
that the receiver is between the initial detection of the start bit and the completion of
the stop bit. When the flag is “1”, it indicates that the receiver is idle. Between the
completion of the stop bit and the detection of the next start bit, the RIDLE bit is “1”
indicating that the UART receiver is idle and the RX pin stays in logic high condition.
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HT67F488/HT67F489
TinyPowerTM A/D 8-Bit Flash MCU with LCD & EEPROM
Bit 2RXIF: Receive RXR data register status
0: RXR data register is empty
1: RXR data register has available data
The RXIF flag is the receive data register status flag. When this read only flag is “0”,
it indicates that the RXR read data register is empty. When the flag is “1”, it indicates
that the RXR read data register contains new data. When the contents of the shift
register are transferred to the RXR register, an interrupt is generated if RIE=1 in the
UCR2 register. If one or more errors are detected in the received word, the appropriate
receive-related flags NF, FERR, and/or PERR are set within the same clock cycle. The
RXIF flag is cleared when the USR register is read with RXIF set, followed by a read
from the RXR register, and if the RXR register has no data available.
Bit 1TIDLE: Transmission idle
0: Data transmission is in progress (data being transmitted)
1: No data transmission is in progress (transmitter is idle)
The TIDLE flag is known as the transmission complete flag. When this read only
flag is “0”, it indicates that a transmission is in progress. This flag will be set to “1”
when the TXIF flag is “1” and when there is no transmit data or break character being
transmitted. When TIDLE is equal to “1”, the TX pin becomes idle with the pin state
in logic high condition. The TIDLE flag is cleared by reading the USR register with
TIDLE set and then writing to the TXR register. The flag is not generated when a data
character or a break is queued and ready to be sent.
Bit 0TXIF: Transmit TXR data register status
0: Character is not transferred to the transmit shift register
1: Character has transferred to the transmit shift register (TXR data register is
empty)
The TXIF flag is the transmit data register empty flag. When this read only flag is “0”,
it indicates that the character is not transferred to the transmitter shift register. When
the flag is “1”, it indicates that the transmitter shift register has received a character
from the TXR data register. The TXIF flag is cleared by reading the UART status
register (USR) with TXIF set and then writing to the TXR data register. Note that
when the TXEN bit is set, the TXIF flag bit will also be set since the transmit data
register is not yet full.
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TinyPower
TM
HT67F488/HT67F489
A/D 8-Bit Flash MCU with LCD & EEPROM
UCR1 Register
The UCR1 register together with the UCR2 register are the two UART control registers that are used
to set the various options for the UART function, such as overall on/off control, parity control, data
transfer bit length etc. Further explanation on each of the bits is given below:
Bit
7
6
5
4
3
2
1
0
Name
UARTEN
BNO
PREN
PRT
STOPS
TXBRK
RX8
TX8
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R
W
POR
0
0
0
0
0
0
x
0
“x” unknown
Bit 7UARTEN: UART function enable control
0: Disable UART. TX and RX pins are as I/O or other pin-shared functional pins
1: Enable UART. TX and RX pins function as UART pins
The UARTEN bit is the UART enable bit. If the TX and RX pins are shared with the
LCD outputs and the UART interface and LCD driver are both enabled simultaneously,
the LCD driver will have the priority to use the corresponding pins as LCD outputs.
When this bit is equal to “0”, the UART will be disabled and the RX pin as well as the
TX pin will be as General Purpose I/O or other pin-shared functional pins. When the
bit is equal to “1”, the UART will be enabled and the TX and RX pins will function as
defined by the TXEN and RXEN enable control bits.
When the UART is disabled, it will empty the buffer so any character remaining in
the buffer will be discarded. In addition, the value of the baud rate counter will be
reset. If the UART is disabled, all error and status flags will be reset. Also the TXEN,
RXEN, TXBRK, RXIF, OERR, FERR, PERR and NF bits will be cleared, while the
TIDLE, TXIF and RIDLE bits will be set. Other control bits in UCR1, UCR2 and
BRG registers will remain unaffected. If the UART is active and the UARTEN bit is
cleared, all pending transmissions and receptions will be terminated and the module
will be reset as defined above. When the UART is re-enabled, it will restart in the
same configuration.
Bit 6BNO: Number of data transfer bits selection
0: 8-bit data transfer
1: 9-bit data transfer
This bit is used to select the data length format, which can have a choice of either
8-bit or 9-bit format. When this bit is equal to “1”, a 9-bit data length format will be
selected. If the bit is equal to “0”, then an 8-bit data length format will be selected. If
9-bit data length format is selected, then bits RX8 and TX8 will be used to store the
9th bit of the received and transmitted data respectively.
Bit 5PREN: Parity function enable control
0: Parity function is disabled
1: Parity function is enabled
This is the parity enable bit. When this bit is equal to “1”, the parity function will be
enabled. If the bit is equal to “0”, then the parity function will be disabled. Replace the
most significant bit position with a parity bit.
Bit 4PRT: Parity type selection bit
0: Even parity for parity generator
1: Odd parity for parity generator
This bit is the parity type selection bit. When this bit is equal to “1”, odd parity type
will be selected. If the bit is equal to “0”, then even parity type will be selected.
Bit 3STOPS: Number of Stop bits selection
0: One stop bit format is used
1: Two stop bits format is used
This bit determines if one or two stop bits are to be used. When this bit is equal to “1”,
two stop bits are used. If this bit is equal to “0”, then only one stop bit is used.
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TinyPowerTM A/D 8-Bit Flash MCU with LCD & EEPROM
Bit 2TXBRK: Transmit break character
0: No break character is transmitted
1: Break characters transmit
The TXBRK bit is the Transmit Break Character bit. When this bit is “0”, there are
no break characters and the TX pin operates normally. When the bit is “1”, there are
transmit break characters and the transmitter will send logic zeros. When this bit is
equal to “1”, after the buffered data has been transmitted, the transmitter output is held
low for a minimum of a 13-bit length and until the TXBRK bit is reset.
Bit 1RX8: Receive data bit 8 for 9-bit data transfer format (read only)
This bit is only used if 9-bit data transfers are used, in which case this bit location will
store the 9th bit of the received data known as RX8. The BNO bit is used to determine
whether data transfers are in 8-bit or 9-bit format.
Bit 0TX8: Transmit data bit 8 for 9-bit data transfer format (write only)
This bit is only used if 9-bit data transfers are used, in which case this bit location
will store the 9th bit of the transmitted data known as TX8. The BNO bit is used to
determine whether data transfers are in 8-bit or 9-bit format.
UCR2 Register
The UCR2 register is the second of the two UART control registers and serves several purposes. One
of its main functions is to control the basic enable/disable operation of the UART Transmitter and
Receiver as well as enabling the various UART interrupt sources. The register also serves to control
the baud rate speed, receiver wake-up enable and the address detect enable. Further explanation on
each of the bits is given below:
Bit
7
6
5
4
3
2
1
0
Name
TXEN
RXEN
BRGH
ADDEN
WAKE
R/W
R/W
R/W
R/W
R/W
R/W
RIE
TIIE
TEIE
R/W
R/W
POR
0
0
0
0
0
0
R/W
0
0
Bit 7TXEN: UART Transmitter enabled control
0: UART transmitter is disabled
1: UART transmitter is enabled
The bit named TXEN is the Transmitter Enable Bit. When this bit is equal to “0”, the
transmitter will be disabled with any pending data transmissions being aborted. In
addition the buffers will be reset. In this situation the TX pin will be used as an I/O or
other pin-shared functional pin.
If the TXEN bit is equal to “1” and the UARTEN bit is also equal to “1”, the
transmitter will be enabled and the TX pin will be controlled by the UART. Clearing
the TXEN bit during a transmission will cause the data transmission to be aborted and
will reset the transmitter. If this situation occurs, the TX pin will be used as an I/O or
other pin-shared functional pin.
Bit 6RXEN: UART Receiver enabled control
0: UART receiver is disabled
1: UART receiver is enabled
The bit named RXEN is the Receiver Enable Bit. When this bit is equal to “0”, the
receiver will be disabled with any pending data receptions being aborted. In addition
the receive buffers will be reset. In this situation the RX pin will be used as an I/O or
other pin-shared functional pin. If the RXEN bit is equal to “1” and the UARTEN bit
is also equal to “1”, the receiver will be enabled and the RX pin will be controlled by
the UART. Clearing the RXEN bit during a reception will cause the data reception to
be aborted and will reset the receiver. If this situation occurs, the RX pin will be used
as an I/O or other pin-shared functional pin.
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TinyPower
TM
HT67F488/HT67F489
A/D 8-Bit Flash MCU with LCD & EEPROM
Bit 5BRGH: Baud Rate speed selection
0: Low speed baud rate
1: High speed baud rate
The bit named BRGH selects the high or low speed mode of the Baud Rate Generator.
This bit, together with the value placed in the baud rate register BRG, controls the
Baud Rate of the UART. If this bit is equal to “1”, the high speed mode is selected. If
the bit is equal to “0”, the low speed mode is selected.
Bit 4ADDEN: Address detect function enable control
0: Address detect function is disabled
1: Address detect function is enabled
The bit named ADDEN is the address detect function enable control bit. When this
bit is equal to “1”, the address detect function is enabled. When it occurs, if the 8th
bit, which corresponds to RX7 if BNO=0 or the 9th bit, which corresponds to RX8 if
BNO=1, has a value of “1”, then the received word will be identified as an address,
rather than data. If the corresponding interrupt is enabled, an interrupt request will be
generated each time the received word has the address bit set, which is the 8th or 9th
bit depending on the value of BNO. If the address bit known as the 8th or 9th bit of the
received word is “0” with the address detect function being enabled, an interrupt will
not be generated and the received data will be discarded.
Bit 3WAKE: RX pin falling edge wake-up function enable control
0: RX pin wake-up function is disabled
1: RX pin wake-up function is enabled
This bit enables or disables the receiver wake-up function. If this bit is equal to “1”
and the MCU is in the SLEEP mode, a falling edge on the RX input pin will wakeup the device. Please reference the UART RX pin wake-up functions in different
operating mode for the detail. If this bit is equal to “0” and the MCU is in the SLEEP
mode, any edge transitions on the RX pin will not wake-up the device.
Bit 2RIE: Receiver interrupt enable control
0: Receiver related interrupt is disabled
1: Receiver related interrupt is enabled
This bit enables or disables the receiver interrupt. If this bit is equal to “1” and when
the receiver overrun flag OERR or receive data available flag RXIF is set, the UART
interrupt request flag will be set. If this bit is equal to “0”, the UART interrupt request
flag will not be influenced by the condition of the OERR or RXIF flags.
Bit 1TIIE: Transmitter Idle interrupt enable control
0: Transmitter idle interrupt is disabled
1: Transmitter idle interrupt is enabled
This bit enables or disables the transmitter idle interrupt. If this bit is equal to “1” and
when the transmitter idle flag TIDLE is set, due to a transmitter idle condition, the
UART interrupt request flag will be set. If this bit is equal to “0”, the UART interrupt
request flag will not be influenced by the condition of the TIDLE flag.
Bit 0TEIE: Transmitter Empty interrupt enable control
0: Transmitter empty interrupt is disabled
1: Transmitter empty interrupt is enabled
This bit enables or disables the transmitter empty interrupt. If this bit is equal to “1”
and when the transmitter empty flag TXIF is set, due to a transmitter empty condition,
the UART interrupt request flag will be set. If this bit is equal to “0”, the UART
interrupt request flag will not be influenced by the condition of the TXIF flag.
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TinyPowerTM A/D 8-Bit Flash MCU with LCD & EEPROM
TXR/RXR Register
Bit
7
6
5
4
3
2
1
0
Name
TXRX7
TXRX6
TXRX5
TXRX4
TXRX3
TXRX2
TXRX1
TXRX0
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 7~0TXRX7~TXRX0: UART Transmit/Receive Data bit 7 ~ bit 0
BRG Register
Bit
7
6
5
4
3
2
1
0
Name
BRG7
BRG6
BRG5
BRG4
BRG3
BRG2
BRG1
BRG0
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 7~0BRG7~BRG0: Baud Rate values
By programming the BRGH bit in UCR2 Register which allows selection of the
related formula described above and programming the required value in the BRG
register, the required baud rate can be setup.
Note: Baud rate= fSYS/[64×(N+1)] if BRGH=0.
Baud rate= fSYS/[16×(N+1)] if BRGH=1.
Baud Rate Generator
To setup the speed of the serial data communication, the UART function contains its own dedicated
baud rate generator. The baud rate is controlled by its own internal free running 8-bit timer, the
period of which is determined by two factors. The first of these is the value placed in the baud rate
register BRG and the second is the value of the BRGH bit with the control register UCR2. The
BRGH bit decides if the baud rate generator is to be used in a high speed mode or low speed mode,
which in turn determines the formula that is used to calculate the baud rate. The value N in the BRG
register which is used in the following baud rate calculation formula determines the division factor.
Note that N is the decimal value placed in the BRG register and has a range of between 0 and 255.
UCR2 BRGH Bit
0
1
Baud Rate (BR)
fSYS / [64 (N+1)]
fSYS / [16 (N+1)]
By programming the BRGH bit which allows selection of the related formula and programming the
required value in the BRG register, the required baud rate can be setup. Note that because the actual
baud rate is determined using a discrete value, N, placed in the BRG register, there will be an error
associated between the actual and requested value. The following example shows how the BRG
register value N and the error value can be calculated.
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TinyPower
TM
HT67F488/HT67F489
A/D 8-Bit Flash MCU with LCD & EEPROM
Calculating the Register and Error Values
For a clock frequency of 4MHz, and with BRGH set to “0” determine the BRG register value N, the
actual baud rate and the error value for a desired baud rate of 4800.
From the above table the desired baud rate BR = fSYS / [64 (N+1)]
Re-arranging this equation gives N = [fSYS / (BR×64)] - 1
Giving a value for N = [4000000 / (4800×64)] - 1 = 12.0208
To obtain the closest value, a decimal value of 12 should be placed into the BRG register. This gives
an actual or calculated baud rate value of BR = 4000000 / [64×(12 + 1)] = 4808
Therefore the error is equal to (4808 - 4800) / 4800 = 0.16%
The following table shows actual values of baud rate and error values for the two values of BRGH.
fSYS=8MHz
Baud Rate
K/BPS
Baud Rates for BRGH=0
BRG
Kbaud
Baud Rates for BRGH=1
Error (%)
BRG
Kbaud
Error (%)
—
0.3
—
—
—
—
—
1.2
103
1.202
0.16
—
—
—
2.4
51
2.404
0.16
207
2.404
0.16
4.8
25
4.808
0.16
103
4.808
0.16
9.6
12
9.615
0.16
51
9.615
0.16
19.2
6
17.8857
-6.99
25
19.231
0.16
38.4
2
41.667
8.51
12
38.462
0.16
57.6
1
62.500
8.51
8
55.556
-3.55
115.2
0
125
8.51
3
125
8.51
250
—
—
—
1
250
0
Baud Rates and Error Values
UART Setup and Control
For data transfer, the UART function utilizes a non-return-to-zero, more commonly known as NRZ,
format. This is composed of one start bit, eight or nine data bits, and one or two stop bits. Parity
is supported by the UART hardware, and can be setup to be even, odd or no parity. For the most
common data format, 8 data bits along with no parity and one stop bit, denoted as 8, N, 1, is used
as the default setting, which is the setting at power-on. The number of data bits and stop bits, along
with the parity, are setup by programming the corresponding BNO, PRT, PREN, and STOPS bits
in the UCR1 register. The baud rate used to transmit and receive data is setup using the internal
8-bit baud rate generator, while the data is transmitted and received LSB first. Although the UART
transmitter and receiver are functionally independent, they both use the same data format and baud
rate. In all cases stop bits will be used for data transmission.
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Enabling/Disabling the UART
The basic on/off function of the internal UART function is controlled using the UARTEN bit in the
UCR1 register. If the UARTEN, TXEN and RXEN bits are set, then these two UART pins will act
as normal TX output pin and RX input pin respectively. If no data is being transmitted on the TX
pin, then it will default to a logic high value.
Clearing the UARTEN bit will disable the TX and RX pins and allow these two pins to be used as
normal I/O or other pin-shared functional pins. When the UART function is disabled the buffer will
be reset to an empty condition, at the same time discarding any remaining residual data. Disabling
the UART will also reset the error and status flags with bits TXEN, RXEN, TXBRK, RXIF, OERR,
FERR, PERR and NF being cleared while bits TIDLE, TXIF and RIDLE will be set. The remaining
control bits in the UCR1, UCR2 and BRG registers will remain unaffected. If the UARTEN bit in
the UCR1 register is cleared while the UART is active, then all pending transmissions and receptions
will be immediately suspended and the UART will be reset to a condition as defined above. If the
UART is then subsequently re-enabled, it will restart again in the same configuration.
Data, Parity and Stop bit Selection
The format of the data to be transferred is composed of various factors such as data bit length,
parity on/off, parity type, address bits and the number of stop bits. These factors are determined by
the setup of various bits within the UCR1 register. The BNO bit controls the number of data bits
which can be set to either 8 or 9, the PRT bit controls the choice of odd or even parity, the PREN
bit controls the parity on/off function and the STOPS bit decides whether one or two stop bits are to
be used. The following table shows various formats for data transmission. The address bit identifies
the frame as an address character. The number of stop bits, which can be either one or two, is
independent of the data length.
Start Bit
Data Bits
Address Bits
Parity Bits
Stop Bit
Example of 8-bit Data Formats
1
8
0
0
1
1
7
0
1
1
1
7
1
0
1
Example of 9-bit Data Formats
1
9
0
0
1
1
8
0
1
1
1
8
1
0
1
Transmitter Receiver Data Format
The following diagram shows the transmit and receive waveforms for both 8-bit and 9-bit data
formats.
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UART Transmitter
Data word lengths of either 8 or 9 bits can be selected by programming the BNO bit in the UCR1
register. When BNO bit is set, the word length will be set to 9 bits. In this case the 9th bit, which
is the MSB, needs to be stored in the TX8 bit in the UCR1 register. At the transmitter core lies the
Transmitter Shift Register, more commonly known as the TSR, whose data is obtained from the
transmit data register, which is known as the TXR register. The data to be transmitted is loaded
into this TXR register by the application program. The TSR register is not written to with new data
until the stop bit from the previous transmission has been sent out. As soon as this stop bit has been
transmitted, the TSR can then be loaded with new data from the TXR register, if it is available. It
should be noted that the TSR register, unlike many other registers, is not directly mapped into the
Data Memory area and as such is not available to the application program for direct read/write
operations. An actual transmission of data will normally be enabled when the TXEN bit is set, but
the data will not be transmitted until the TXR register has been loaded with data and the baud rate
generator has defined a shift clock source. However, the transmission can also be initiated by first
loading data into the TXR register, after which the TXEN bit can be set. When a transmission of
data begins, the TSR is normally empty, in which case a transfer to the TXR register will result in
an immediate transfer to the TSR. If during a transmission the TXEN bit is cleared, the transmission
will immediately cease and the transmitter will be reset. The TX output pin will then return to the I/O
or other pin-shared function.
Transmitting Data
When the UART is transmitting data, the data is shifted on the TX pin from the shift register, with
the least significant bit first. In the transmit mode, the TXR register forms a buffer between the
internal bus and the transmitter shift register. It should be noted that if 9-bit data format has been
selected, then the MSB will be taken from the TX8 bit in the UCR1 register. The steps to initiate a
data transfer can be summarized as follows:
• Make the correct selection of the BNO, PRT, PREN and STOPS bits to define the required word
length, parity type and number of stop bits.
• Setup the BRG register to select the desired baud rate.
• Set the TXEN bit to ensure that the TX pin is used as a UART transmitter pin.
• Access the USR register and write the data that is to be transmitted into the TXR register. Note
that this step will clear the TXIF bit.
• This sequence of events can now be repeated to send additional data.
• It should be noted that when TXIF=0, data will be inhibited from being written to the TXR
register. Clearing the TXIF flag is always achieved using the following software sequence:
♦♦
A USR register access
♦♦
A TXR register write execution
The read-only TXIF flag is set by the UART hardware and if set indicates that the TXR register is
empty and that other data can now be written into the TXR register without overwriting the previous
data. If the TEIE bit is set then the TXIF flag will generate an interrupt.
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During a data transmission, a write instruction to the TXR register will place the data into the TXR
register, which will be copied to the shift register at the end of the present transmission. When there
is no data transmission in progress, a write instruction to the TXR register will place the data directly
into the shift register, resulting in the commencement of data transmission, and the TXIF bit being
immediately set. When a frame transmission is complete, which happens after stop bits are sent
or after the break frame, the TIDLE bit will be set. To clear the TIDLE bit the following software
sequence is used:
• A USR register access
• A TXR register write execution
Note that both the TXIF and TIDLE bits are cleared by the same software sequence.
Transmit Break
If the TXBRK bit is set then break characters will be sent on the next transmission. Break character
transmission consists of a start bit, followed by 13×N ‘0’ bits and stop bits, where N=1, 2, etc. If a
break character is to be transmitted then the TXBRK bit must be first set by the application program,
then cleared to generate the stop bits. Transmitting a break character will not generate a transmit
interrupt. Note that a break condition length is at least 13 bits long. If the TXBRK bit is continually
kept at a logic high level then the transmitter circuitry will transmit continuous break characters.
After the application program has cleared the TXBRK bit, the transmitter will finish transmitting the
last break character and subsequently send out one or two stop bits. The automatic logic highs at the
end of the last break character will ensure that the start bit of the next frame is recognized.
UART Receiver
The UART is capable of receiving word lengths of either 8 or 9 bits. If the BNO bit is set, the word
length will be set to 9 bits with the MSB being stored in the RX8 bit of the UCR1 register. At the
receiver core lies the Receive Serial Shift Register, commonly known as the RSR. The data which
is received on the RX external input pin, is sent to the data recovery block. The data recovery block
operating speed is 16 times that of the baud rate, while the main receive serial shifter operates at the
baud rate. After the RX pin is sampled for the stop bit, the received data in RSR is transferred to the
receive data register, if the register is empty. The data which is received on the external RX input pin
is sampled three times by a majority detect circuit to determine the logic level that has been placed
onto the RX pin. It should be noted that the RSR register, unlike many other registers, is not directly
mapped into the Data Memory area and as such is not available to the application program for direct
read/write operations.
Receiving Data
When the UART receiver is receiving data, the data is serially shifted in on the external RX input
pin, LSB first. In the read mode, the RXR register forms a buffer between the internal bus and the
receiver shift register. The RXR register is a two byte deep FIFO data buffer, where two bytes can
be held in the FIFO while a third byte can continue to be received. Note that the application program
must ensure that the data is read from RXR before the third byte has been completely shifted
in, otherwise this third byte will be discarded and an overrun error OERR will be subsequently
indicated. The steps to initiate a data transfer can be summarized as follows:
• Make the correct selection of BNO, PRT, PREN and STOPS bits to define the word length, parity
type and number of stop bits.
• Setup the BRG register to select the desired baud rate.
• Set the RXEN bit to ensure that the RX pin is used as a UART receiver pin.
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At this point the receiver will be enabled which will begin to look for a start bit.
When a character is received the following sequence of events will occur:
• The RXIF bit in the USR register will be set when RXR register has data available, at least one
more character can be read.
• When the contents of the shift register have been transferred to the RXR register, then if the RIE
bit is set, an interrupt will be generated.
• If during reception, a frame error, noise error, parity error, or an overrun error has been detected,
then the error flags can be set.
The RXIF bit can be cleared using the following software sequence:
• A USR register access
• An RXR register read execution
Receive Break
Any break character received by the UART will be managed as a framing error. The receiver will
count and expect a certain number of bit times as specified by the values programmed into the BNO
and STOPS bits. If the break is much longer than 13 bit times, the reception will be considered as
complete after the number of bit times specified by BNO and STOPS. The RXIF bit is set, FERR
is set, zeros are loaded into the receive data register, interrupts are generated if appropriate and the
RIDLE bit is set. If a long break signal has been detected and the receiver has received a start bit,
the data bits and the invalid stop bit, which sets the FERR flag, the receiver must wait for a valid
stop bit before looking for the next start bit. The receiver will not make the assumption that the
break condition on the line is the next start bit. A break is regarded as a character that contains only
zeros with the FERR flag set. The break character will be loaded into the buffer and no further data
will be received until stop bits are received. It should be noted that the RIDLE read only flag will go
high when the stop bits have not yet been received. The reception of a break character on the UART
registers will result in the following:
• The framing error flag, FERR, will be set.
• The receive data register, RXR, will be cleared.
• The OERR, NF, PERR, RIDLE or RXIF flags will possibly be set.
Idle Status
When the receiver is reading data, which means it will be in between the detection of a start bit and
the reading of a stop bit, the receiver status flag in the USR register, otherwise known as the RIDLE
flag, will have a zero value. In between the reception of a stop bit and the detection of the next start
bit, the
RIDLE flag will have a high value, which indicates the receiver is in an idle condition.
Receiver interrupt
The read only receive interrupt flag RXIF in the USR register is set by an edge generated by the
receiver. An interrupt is generated if RIE=1, when a word is transferred from the Receive Shift
Register, RSR, to the Receive Data Register, RXR. An overrun error can also generate an interrupt if
RIE=1.
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Managing Receiver Errors
Several types of reception errors can occur within the UART module, the following section describes
the various types and how they are managed by the UART.
Overrun Error – OERR Flag
The RXR register is composed of a two byte deep FIFO data buffer, where two bytes can be held
in the FIFO register, while a third byte can continue to be received. Before this third byte has been
entirely shifted in, the data should be read from the RXR register. If this is not done, the overrun
error flag OERR will be consequently indicated.
In the event of an overrun error occurring, the following will happen:
• The OERR flag in the USR register will be set.
• The RXR contents will not be lost.
• The shift register will be overwritten.
• An interrupt will be generated if the RIE bit is set.
The OERR flag can be cleared by an access to the USR register followed by a read to the RXR
register.
Noise Error – NF Flag
Over-sampling is used for data recovery to identify valid incoming data and noise. If noise is
detected within a frame the following will occur:
• The read only noise flag, NF, in the USR register will be set on the rising edge of the RXIF bit.
• Data will be transferred from the Shift register to the RXR register.
• No interrupt will be generated. However this bit rises at the same time as the RXIF bit which
itself generates an interrupt.
Note that the NF flag is reset by a USR register read operation followed by an RXR register read
operation.
Framing Error – FERR Flag
The read only framing error flag, FERR, in the USR register, is set if a zero is detected instead of
stop bits. If two stop bits are selected, both stop bits must be high, otherwise the FERR flag will be
set. The FERR flag is buffered along with the received data and is cleared on any reset.
Parity Error – PERR Flag
The read only parity error flag, PERR, in the USR register, is set if the parity of the received word is
incorrect. This error flag is only applicable if the parity is enabled, PREN = 1, and if the parity type,
odd or even is selected. The read only PERR flag is buffered along with the received data bytes. It is
cleared on any reset. It should be noted that the FERR and PERR flags are buffered along with the
corresponding word and should be read before reading the data word.
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UART Module Interrupt Structure
Several individual UART conditions can generate a UART interrupt. When these conditions exist,
a low pulse will be generated to get the attention of the microcontroller. These conditions are a
transmitter data register empty, transmitter idle, receiver data available, receiver overrun, address
detect and an RX pin wake-up. When any of these conditions are created, if its corresponding
interrupt control is enabled and the stack is not full, the program will jump to its corresponding
interrupt vector where it can be serviced before returning to the main program. Four of these
conditions have the corresponding USR register flags which will generate a UART interrupt if its
associated interrupt enable control bit in the UCR2 register is set. The two transmitter interrupt
conditions have their own corresponding enable control bits, while the two receiver interrupt
conditions have a shared enable control bit. These enable bits can be used to mask out individual
UART interrupt sources.
The address detect condition, which is also a UART interrupt source, does not have an associated
flag, but will generate a UART interrupt when an address detect condition occurs if its function
is enabled by setting the ADDEN bit in the UCR2 register. An RX pin wake-up, which is also a
UART interrupt source, does not have an associated flag, but will generate a UART interrupt if the
microcontroller is woken up by a falling edge on the RX pin, if the WAKE and RIE bits in the UCR
register are set. Note that in the event of an RX wake-up interrupt occurring, there will be a certain
period of delay, commonly known as the System Start-up Time, for the oscillator to restart and
stabilize before the system resumes normal operation.
Note that the USR register flags are read only and cannot be cleared or set by the application
program, neither will they be cleared when the program jumps to the corresponding interrupt
servicing routine, as is the case for some of the other interrupts. The flags will be cleared
automatically when certain actions are taken by the UART, the details of which are given in the
UART register section. The overall UART interrupt can be disabled or enabled by the related
interrupt enable control bits in the interrupt control registers of the microcontroller to decide whether
the interrupt requested by the UART module is masked out or allowed.
USR Register
UCR2 Register
Transmitter Empty
Flag TXIF
TEIE
Transmitter Idle
Flag TIDLE
TIIE
0
1
RIE
0
1
Receiver Overrun
Flag OERR
OR
Receiver Data
Available RXIF
RX Pin
Wake-up
WAKE
ADDEN
0
1
UCR2 Register
0
1
UART Interrupt
Request Flag
UARF
INTC2
Register
UARE
INTC0
Register
EMI
0
1
0
1
RX7 if BNO=0
RX8 if BNO=1
UART Interrupt Scheme
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Address Detect Mode
Setting the Address Detect Mode bit, ADDEN, in the UCR2 register, enables this special mode. If
this bit is enabled then an additional qualifier will be placed on the generation of a Receiver Data
Available interrupt, which is requested by the RXIF flag. If the ADDEN bit is enabled, then when
data is available, an interrupt will only be generated, if the highest received bit has a high value.
Note that the MFE, URE and EMI interrupt enable bits must also be enabled for correct interrupt
generation. This highest address bit is the 9th bit if BNO=1 or the 8th bit if BNO=0. If this bit
is high, then the received word will be defined as an address rather than data. A Data Available
interrupt will be generated every time the last bit of the received word is set. If the ADDEN bit
is not enabled, then a Receiver Data Available interrupt will be generated each time the RXIF
flag is set, irrespective of the data last bit status. The address detect mode and parity enable are
mutually exclusive functions. Therefore if the address detect mode is enabled, then to ensure correct
operation, the parity function should be disabled by resetting the parity enable bit to zero.
ADDEN
0
1
Bit 9 if BNO=1,
Bit 8 if BNO=0
UART Interrupt Generated
0
√
1
√
0
×
1
√
ADDEN Bit Function
UART Module Power Down and Wake-up
When the MCU is in the Power Down Mode, the UART will cease to function. When the device
enters the Power Down Mode, all clock sources to the module are shutdown. If the MCU enters the
Power Down Mode while a transmission is still in progress, then the transmission will be paused
until the UART clock source derived from the microcontroller is activated. In a similar way, if the
MCU enters the Power Down Mode while receiving data, then the reception of data will likewise be
paused. When the MCU enters the Power Down Mode, note that the USR, UCR1, UCR2, transmit
and receive registers, as well as the BRG register will not be affected. It is recommended to make
sure first that the UART data transmission or reception has been finished before the microcontroller
enters the Power Down mode.
The UART function contains a receiver RX pin wake-up function, which is enabled or disabled
by the WAKE bit in the UCR2 register. If this bit, along with the UART enable bit, UARTEN, the
receiver enable bit, RXEN and the receiver interrupt bit, RIE, are all set before the MCU enters
the Power Down Mode, then a falling edge on the RX pin will wake up the MCU from the Power
Down Mode. Note that as it takes certain system clock cycles after a wake-up, before normal
microcontroller operation resumes, any data received during this time on the RX pin will be ignored.
For a UART wake-up interrupt to occur, in addition to the bits for the wake-up being set, the global
interrupt enable bit, EMI, and the UART interrupt enable bit, URE, must also be set. If these two
bits are not set then only a wake up event will occur and no interrupt will be generated. Note also
that as it takes certain system clock cycles after a wake-up before normal microcontroller resumes,
the UART interrupt will not be generated until after this time has elapsed.
Below table illustrates the UART RX wake-up functions in different operating mode.
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Operation
Mode
IDLE0 Mode
IDLE1 Mode
Description
RX wake-up function
CPU
fSYS
fH
fSUB
Off
Off
Off
On
When the CPU enters the IDLE0 mode, a falling edge on
the RX pin will not turn on the fSYS clock and not wake up the
CPU even if UCR2.2(RIE)=1 and UCR2.3(WAKE)=1.
On
When the UCR2.2(RIE)=1, UCR2.3(WAKE)=1 and the CPU
is entered in IDLE1 mode:
1. If the UART is not transfer and a falling edge occurred on
the RX pin, this will turn on fSYS and CPU is still off. If the
UART transmission is on going, CPU will be woken up in
the end of transfer.
2. If the UART transmission is on going, the CPU will be
woken up in the end of transfer.
Note: If RIE=0, WAKE=1 and the UART transmission is on
going, the CPU will not be woken up in the end of
receive.
Off
When the UCR2.2(RIE)=1, UCR2.3(WAKE)=1 and the CPU
is entered in IDLE1 mode:
1. If the UART is not transfer and a falling edge occurred on
the RX pin, this will turn on fSYS and CPU is still off. If the
UART transmission is on going, CPU will be woken up in
the end of transfer.
2. If the UART transmission is on going, the CPU will be
woken up in the end of transfer.
Note: If RIE=0, WAKE=1 and the UART transmission is on
going, the CPU will not be woken up in the end of
receive.
Off
IDLE1 Mode
Off
SLEEP0/1 Mode
Off
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On
On
On
On
(fSYS=fH~fH/64)
Off
When the UCR2.2(RIE)=1, UCR2.3(WAKE)=1 and the CPU
Off On/Off is entered in SLEEP mode, a falling edge on the RX pin will
turn on fSYS and wake-up CPU.
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Interrupts
Interrupts are an important part of any microcontroller system. When an external event or an
internal function such as a Timer Module or an A/D converter requires microcontroller attention,
their corresponding interrupt will enforce a temporary suspension of the main program allowing the
microcontroller to direct attention to their respective needs. The device contains several external
interrupt and internal interrupts functions. The external interrupt is generated by the action of the
external INT0~INT3 pins, while the internal interrupts are generated by various internal functions
such as TMs, Time Base, LVD, EEPROM, UART 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 first is the INTC0~INTC2 registers which setup the primary interrupts,
the second is the MFI0~MFI4 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
INTn Pin
Enable Bit
Request Flag
EMI
—
Notes
—
INTnE
INTnF
n=0~3
A/D Converter
ADE
ADF
—
Multi-function
MFnE
MFnF
n=0~4
Time Base
TBnE
TBnF
n=0 or 1
LVD
LVE
LVF
—
EEPROM
DEE
DEF
—
UARE
UARF
—
TnPE
TnPF
n=0~3
TnAE
TnAF
n=0~3
UART
TM
Interrupt Register Bit Naming Conventions
Note: The EEPROM Interrupt is only for the HT67F489.
Interrupt Register Contents
Bit
Register
Name
7
6
5
4
3
2
1
0
INTEG
INT3S1
INT3S0
INT2S1
INT2S0
INT1S1
INT1S0
INT0S1
INT0S0
INTC0
—
MF0F
INT1F
INT0F
MF0E
INT1E
INT0E
EMI
INTC1
ADF
MF3F
MF2F
MF1F
ADE
MF3E
MF2E
MF1E
INTC2
MF4F
INT3F
INT2F
UARF
MF4E
INT3E
INT2E
UARE
MFI0
—
—
T0AF
T0PF
—
—
T0AE
T0PE
MFI1
—
—
T1AF
T1PF
—
—
T1AE
T1PE
MFI2
—
—
T2AF
T2PF
—
—
T2AE
T2PE
MFI3
—
—
T3AF
T3PF
—
—
T3AE
T3PE
MFI4
TB1F
TB0F
DEF
LVF
TB1E
TB0E
DEE
LVE
Note: The EEPROM Interrupt is only for the HT67F489.
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INTEG Register
Bit
7
6
5
4
3
2
1
0
Name
INT3S1
INT3S0
INT2S1
INT2S0
INT1S1
INT1S0
INT0S1
INT0S0
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 7~6INT3S1~INT3S0: Interrupt edge control for INT3 pin
00: Disable
01: Rising edge
10: Falling edge
11: Both rising and falling edges
Bit 5~4INT2S1~INT2S0: Interrupt edge control for INT2 pin
00: Disable
01: Rising edge
10: Falling edge
11: Both rising and falling edges
Bit 3~2INT1S1~INT1S0: Interrupt edge control for INT1 pin
00: Disable
01: Rising edge
10: Falling edge
11: Both rising and falling edges
Bit 1~0INT0S1~INT0S0: Interrupt edge control for INT0 pin
00: Disable
01: Rising edge
10: Falling edge
11: Both rising and falling edges
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INTC0 Register
Bit
7
6
5
4
3
2
1
Name
—
MF0F
INT1F
INT0F
MF0E
INT1E
INT0E
EMI
R/W
—
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
—
0
0
0
0
0
0
0
Bit 7
0
Unimplemented, read as “0”
Bit 6MF0F: Multi-function Interrupt 0 Request Flag
0: No request
1: Interrupt request
Bit 5INT1F: INT1 Interrupt Request Flag
0: No request
1: Interrupt request
Bit 4INT0F: INT0 Interrupt Request Flag
0: No request
1: Interrupt request
Bit 3MF0E: Multi-function 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
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INTC1 Register
Bit
7
6
5
4
3
2
1
0
Name
ADF
MF3F
MF2F
MF1F
ADE
MF3E
MF2E
MF1E
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 7ADF: A/D Converter Interrupt Request Flag
0: No request
1: Interrupt request
Bit 6MF3F: Multi-function Interrupt 3 Request Flag
0: No request
1: Interrupt request
Bit 5MF2F: Multi-function Interrupt 2 Request Flag
0: No request
1: Interrupt request
Bit 4MF1F: Multi-function Interrupt 1 Request Flag
0: No request
1: Interrupt request
Bit 3ADE: A/D Converter Interrupt Control
0: Disable
1: Enable
Bit 2MF3E: Multi-function 3 Interrupt Control
0: Disable
1: Enable
Bit 1MF2E: Multi-function 2 Interrupt Control
0: Disable
1: Enable
Bit 0MF1E: Multi-function 1 Interrupt Control
0: Disable
1: Enable
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TinyPowerTM A/D 8-Bit Flash MCU with LCD & EEPROM
INTC2 Register
Bit
7
6
5
4
3
2
1
0
Name
MF4F
INT3F
INT2F
UARF
MF4E
INT3E
INT2E
UARE
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 7MF4F: Multi-function Interrupt 4 Request Flag
0: No request
1: Interrupt request
Bit 6INT3F: INT3 pin interrupt request flag
0: No request
1: Interrupt request
Bit 5INT2F: INT2 pin interrupt request flag
0: No request
1: Interrupt request
Bit 4UARF: UART interrupt request flag
0: No request
1: Interrupt request
Bit 3MF4E: Multi-function 4 Interrupt Control
0: Disable
1: Enable
Bit 2INT3E: INT3 pin interrupt control
0: Disable
1: Enable
Bit 1INT2E: INT2 pin interrupt control
0: Disable
1: Enable
Bit 0UARE: UART interrupt control
0: Disable
1: Enable
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TM
HT67F488/HT67F489
A/D 8-Bit Flash MCU with LCD & EEPROM
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
MFI1 Register
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
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MFI2 Register
Bit
7
6
5
4
3
2
1
0
Name
—
—
T2AF
T2PF
—
—
T2AE
T2PE
R/W
—
—
R/W
R/W
—
—
R/W
R/W
POR
—
—
0
0
—
—
0
0
Bit 7~6
Unimplemented, read as “0”
Bit 5T2AF: TM2 Comparator A match interrupt request flag
0: No request
1: Interrupt request
Bit 4T2PF: TM2 Comparator P match interrupt request flag
0: No request
1: Interrupt request
Bit 3~2
Unimplemented, read as “0”
Bit 1T2AE: TM2 Comparator A match interrupt control
0: Disable
1: Enable
Bit 0T2PE: TM2 Comparator P match interrupt control
0: Disable
1: Enable
MFI3 Register
Bit
7
6
5
4
3
2
1
0
Name
—
—
T3AF
T3PF
—
—
T3AE
T3PE
R/W
—
—
R/W
R/W
—
—
R/W
R/W
POR
—
—
0
0
—
—
0
0
Bit 7~6
Unimplemented, read as “0”
Bit 5T3AF: TM3 Comparator A match interrupt request flag
0: No request
1: Interrupt request
Bit 4T3PF: TM3 Comparator P match interrupt request flag
0: No request
1: Interrupt request
Bit 3~2
Unimplemented, read as “0”
Bit 1T3AE: TM3 Comparator A match interrupt control
0: Disable
1: Enable
Bit 0T3PE: TM3 Comparator P match interrupt control
0: Disable
1: Enable
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TM
HT67F488/HT67F489
A/D 8-Bit Flash MCU with LCD & EEPROM
MFI4 Register
Bit
7
6
5
4
3
2
1
Name
TB1F
TB0F
R/W
R/W
R/W
POR
0
0
0
DEF
LVF
TB1E
TB0E
DEE
LVE
R/W
R/W
R/W
R/W
R/W
R/W
0
0
0
0
0
0
Bit 7TB1F: Time Base 1 Interrupt Request Flag
0: No request
1: Interrupt request
Bit 6TB0F: Time Base 0 Interrupt Request Flag
0: No request
1: Interrupt request
Bit 5DEF: Data EEPROM interrupt request flag
0: No request
1: Interrupt request
Bit 4LVF: LVD interrupt request flag
0: No request
1: Interrupt request
Bit 3TB1E: Time Base 1 Interrupt Control
0: Disable
1: Enable
Bit 2TB0E: Time Base 0 Interrupt Control
0: Disable
1: Enable
Bit 1DEE: Data EEPROM Interrupt Control
0: Disable
1: Enable
Bit 0LVE: LVD Interrupt Control
0: Disable
1: Enable
Note: The EEPROM Interrupt is only for the HT67F489.
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TinyPowerTM A/D 8-Bit Flash MCU with LCD & EEPROM
Interrupt Operation
When the conditions for an interrupt event occur, such as a TM Comparator P, Comparator A match
or A/D conversion completion etc, the relevant interrupt request flag will be set. Whether the request
flag actually generates a program jump to the relevant interrupt vector is determined by the condition
of the interrupt enable bit. If the enable bit is set high then the program will jump to its relevant
vector, if the enable bit is zero then although the interrupt request flag is set an actual interrupt will
not be generated and the program will not jump to the relevant interrupt vector. The global interrupt
enable bit, if cleared to zero, will disable all interrupts.
When an interrupt is generated, the Program Counter, which stores the address of the next instruction
to be executed, will be transferred onto the stack. The Program Counter will then be loaded with a
new address which will be the value of the corresponding interrupt vector. The microcontroller will
then fetch its next instruction from this interrupt vector. The instruction at this vector will usually
be a “JMP” which will jump to another section of program which is known as the interrupt service
routine. Here is located the code to control the appropriate interrupt. The interrupt service routine
must be terminated with a “RETI”, which retrieves the original Program Counter address from
the stack and allows the microcontroller to continue with normal execution at the point where the
interrupt occurred.
The various interrupt enable bits, together with their associated request flags, are shown in the
Accompanying diagrams with their order of priority. Some interrupt sources have their own
individual vector while others share the same multi-function interrupt vector. Once an interrupt
subroutine is serviced, all the other interrupts will be blocked, as the global interrupt enable bit,
EMI bit will be cleared automatically. This will prevent any further interrupt nesting from occurring.
However, if other interrupt requests occur during this interval, although the interrupt will not be
immediately serviced, the request flag will still be recorded.
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.
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TinyPower
TM
HT67F488/HT67F489
A/D 8-Bit Flash MCU with LCD & EEPROM
Legend
xxF Request Flag – no auto reset in ISR
EMI auto disabled in ISR
xxF Request Flag – auto reset in ISR
Interrupt Request
Name
Flags
xxE Enable Bit
Interrupt
Name
INT0 Pin
INT0F
Enable
Bits
Master
Enable
Vector
INT0E
EMI
04H
EMI
08H
Request
Flags
Enable
Bits
INT1 Pin
INT1F
TM0 P
T0PF
T0PE
M. Funct. 0
MF0F
MF0E
EMI
0CH
TM0 A
T0AF
T0AE
TM1 P
T1PF
T1PE
M. Funct. 1
MF1F
MF1E
EMI
10H
TM1 A
T1AF
T1AE
TM2 P
T2PF
T2PE
M. Funct. 2
MF2F
MF2E
EMI
14H
TM2 A
T2AF
T2AE
TM3 P
T3PF
T3PE
M. Funct. 3
MF3F
MF3E
EMI
18H
TM3 A
T3AF
T3AE
A/D
ADF
ADE
EMI
1CH
UART
UARF
UARE
EMI
20H
INT2 Pin
INT2F
EMI
24H
INT3 Pin
INT3F
INT3E
EMI
28H
M. Funct. 4
MF4F
MF4E
EMI
2CH
LVD
LVF
LVE
EEPROM
DEF
DEE
Time Base 1
TB1F
TB1E
Time Base 0
TB0F
TB0E
Interrupts contained within
Multi-Function Interrupts
INT1E
INT2E
Priority
High
Low
HT67F489 only
Interrupt Structure
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TinyPowerTM A/D 8-Bit Flash MCU with LCD & EEPROM
External Interrupt
The external interrupt is controlled by signal transitions on the INTn pins. An external interrupt
request will take place when the external interrupt request flag, INTnF, is set, which will occur
when a transition, whose type is chosen by the edge select bits, appears on the external interrupt
pin. To allow the program to branch to its respective interrupt vector address, the global interrupt
enable bit, EMI, and respective external interrupt enable bit, INTnE, 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 pin is pin-shared
with I/O pin, it can only be configured as external interrupt pin if the 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 flag,
INTnF, 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 pin 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.
Multi-function Interrupt
Within these devices there are up to four Multi-function interrupts. Unlike the other independent
interrupts, these interrupts have no independent source, but rather are formed from other existing
interrupt sources, namely the TM Interrupts, LVD interrupt, EEPROM interrupt and Time Base
interrupt.
A Multi-function interrupt request will take place the Multi-function interrupt request flag, MFnF
is set. The Multi-function interrupt flag will be set when any of its 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 the Multi-function
interrupt vector will take place. When the interrupt is serviced, the related Multi-Function request
flag, MFnF, will be automatically reset and the EMI bit will be automatically cleared to disable other
interrupts.
However, it must be noted that, although the Multi-function Interrupt flags will be automatically
reset when the interrupt is serviced, the request flags from the original source of the Multi-function
interrupts, namely the TM Interrupts, LVD interrupt, EEPROM interrupt and Time Base interrupt,
will not be automatically reset and must be manually reset by the application program.
A/D Converter Interrupt
The A/D Converter Interrupt is 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.
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TM
HT67F488/HT67F489
A/D 8-Bit Flash MCU with LCD & EEPROM
UART Interrupt
Several individual UART conditions can generate a UART interrupt. When these conditions exist,
a low pulse will be generated to get the attention of the microcontroller. These conditions are a
transmitter data register empty, transmitter idle, receiver data available, receiver overrun, address
detect and an RX pin wake-up. To allow the program to branch to the respective interrupt vector
addresses, the global interrupt enable bit, EMI, and UART interrupt enable bit, UARE, must first
be set. When the interrupt is enabled, the stack is not full and any of these conditions are created,
a subroutine call to the UART Interrupt vector will take place. When the interrupt is serviced, the
UART Interrupt flag, UARF, will be automatically cleared. The EMI bit will also be automatically
cleared to disable other interrupts. However, the USR register flags will be cleared automatically
when certain actions are taken by the UART, the details of which are given in the UART section.
Time Base Interrupt
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, and associated Multi-function interrupt enable bit,
must first be set. When the interrupt is enabled, the stack is not full and the Time Base overflows, a
subroutine call to the Multi-function Interrupt vector will take place. When the Time Base 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 TB0F or TB1F flag
will not be automatically cleared, it has to be cleared by the application program.
The purpose of the Time Base Interrupt is to provide an interrupt signal at fixed time periods. Their
clock sources originate from the internal clock source fTB. This fTB input clock passes through a
divider, the division ratio of which is selected by programming the appropriate bits in the TBC
register to obtain longer interrupt periods whose value ranges. The clock source that generates fTB,
which in turn controls the Time Base interrupt period, can originate from several different sources,
as shown in the System Operating Mode section.
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TinyPowerTM A/D 8-Bit Flash MCU with LCD & EEPROM
TBC Register
Bit
7
6
5
4
3
2
1
0
Name
TBON
TBCK
TB11
TB10
—
TB02
TB01
TB00
R/W
R/W
R/W
R/W
R/W
—
R/W
R/W
R/W
POR
0
0
1
1
—
1
1
1
Bit 7TBON: TB0 and TB1 Control
0: Disable
1: Enable
Bit 6TBCK: Select fTB Clock
0: fTBC
1: fSYS/4
Bit 5~4
TB11, TB10: Select Time Base 1 Time-out Period
00: 4096/fTB
01: 8192/fTB
10: 16384/fTB
11: 32768/fTB
Bit 3
Unimplemented, read as “0”
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 Interrupt
EEPROM Interrupt
The EEPROM interrupt is contained within the Multi-function Interrupt. An EEPROM Interrupt
request will take place when the EEPROM Interrupt request flag, DEF, is set, which occurs
when an EEPROM Write cycle ends. To allow the program to branch to its respective interrupt
vector address, the global interrupt enable bit, EMI, and EEPROM Interrupt enable bit, DEE, and
associated Multi-function interrupt enable bit, must first be set. When the interrupt is enabled, the
stack is not full and an EEPROM Write cycle ends, a subroutine call to the respective EEPROM
Interrupt vector will take place. When the EEPROM Interrupt is serviced, the EMI bit will be
automatically cleared to disable other interrupts, however only the Multi-function interrupt request
flag will be also automatically cleared. As the DEF flag will not be automatically cleared, it has to be
cleared by the application program.
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TM
HT67F488/HT67F489
A/D 8-Bit Flash MCU with LCD & 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 Periodic Type TMs have two interrupts each. All of the TM interrupts are
contained within the Multi-function Interrupts. For each of the Compact and Periodic Type TMs
there are two interrupt request flags TnPF and TnAF and two enable bits TnPE and TnAE. A TM
interrupt request will take place when any of the TM request flags are set, a situation which occurs
when a TM comparator P or A match situation happens.
To allow the program to branch to its respective interrupt vector address, the global interrupt enable
bit, EMI, respective TM Interrupt enable bit, and relevant Multi-function Interrupt enable bit, MFnE,
must first be set. When the interrupt is enabled, the stack is not full and a TM comparator match
situation occurs, a subroutine call to the relevant Multi-function Interrupt vector locations will take
place. When the TM interrupt is serviced, the EMI bit will be automatically cleared to disable other
interrupts, however only the related MFnF flag will be automatically cleared. As the TM interrupt
request flags will not be automatically cleared, they have to be cleared by the application program.
Interrupt Wake-up Function
Each of the interrupt functions has the capability of waking up the microcontroller when in the
SLEEP or IDLE Mode. A wake-up is generated when an interrupt request flag changes from low to
high and is independent of whether the interrupt is enabled or not. Therefore, even though the device
is in the SLEEP or IDLE Mode and its system oscillator stopped, situations such as external edge
transitions on the external interrupt pins, a low power supply voltage or comparator input change
may cause their respective interrupt flag to be set high and consequently generate an interrupt. Care
must therefore be taken if spurious wake-up situations are to be avoided. If an interrupt wake-up
function is to be disabled then the corresponding interrupt request flag should be set high before the
device enters the SLEEP or IDLE Mode. The interrupt enable bits have no effect on the interrupt
wake-up function.
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TinyPowerTM A/D 8-Bit Flash MCU with LCD & 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, MFnF, will be
automatically cleared, the individual request flag for the function needs to be cleared by the
application program.
It is recommended that programs do not use the “CALL” instruction within the interrupt service
subroutine. Interrupts often occur in an unpredictable manner or need to be serviced immediately.
If only one stack is left and the interrupt is not well controlled, the original control sequence will be
damaged once a CALL subroutine is executed in the interrupt subroutine.
Every interrupt has the capability of waking up the microcontroller when it is in SLEEP or IDLE
Mode, the wake up being generated when the interrupt request flag changes from low to high. If it is
required to prevent a certain interrupt from waking up the microcontroller then its respective request
flag should be first set high before enter SLEEP or IDLE Mode.
As only the Program Counter is pushed onto the stack, then when the interrupt is serviced, if the
contents of the accumulator, status register or other registers are altered by the interrupt service
program, their contents should be saved to the memory at the beginning of the interrupt service
routine.
To return from an interrupt subroutine, either a RET or RETI instruction may be executed. The RETI
instruction in addition to executing a return to the main program also automatically sets the EMI
bit high to allow further interrupts. The RET instruction however only executes a return to the main
program leaving the EMI bit in its present zero state and therefore disabling the execution of further
interrupts.
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TM
HT67F488/HT67F489
A/D 8-Bit Flash MCU with LCD & 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: 4.0V
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TinyPowerTM A/D 8-Bit Flash MCU with LCD & 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 4.0V.
When the power supply voltage, VDD, falls below this pre-determined value, the LVDO bit will be
set high indicating a low power supply voltage condition. The Low Voltage Detector function is
supplied by a reference voltage which will be automatically enabled. When the device is powered
down the low voltage detector will remain active if the LVDEN bit is high. After enabling the Low
Voltage Detector, a time delay tLVDS should be allowed for the circuitry to stabilise before reading the
LVDO bit. Note also that as the VDD voltage may rise and fall rather slowly, at the voltage nears that
of VLVD, there may be multiple bit LVDO transitions.
LVD Operation
The Low Voltage Detector also has its own interrupt which is contained within one of the Multifunction interrupts, providing an alternative means of low voltage detection, in addition to polling
the LVDO bit. The interrupt will only be generated after a delay of tLVD after the LVDO bit has been
set high by a low voltage condition. When the device is powered down the Low Voltage Detector
will remain active if the LVDEN bit is high. In this case, the LVF interrupt request flag will be set,
causing an interrupt to be generated if VDD falls below the preset LVD voltage. This will cause the
device to wake-up from the SLEEP or IDLE Mode, however if the Low Voltage Detector wake up
function is not required then the LVF flag should be first set high before the device enters the SLEEP
or IDLE Mode.
When LVD function is enabled, it is recommenced to clear LVD flag first, and then enables interrupt
function to avoid mistake action.
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August 13, 2014
TinyPower
TM
HT67F488/HT67F489
A/D 8-Bit Flash MCU with LCD & EEPROM
Configuration Options
Configuration options refer to certain options within the MCU that are programmed into the device
during the programming process. During the development process, these options are selected using
the HT-IDE software development tools. As these options are programmed into the device using
the hardware programming tools, once they are selected they cannot be changed later using the
application program. All options must be defined for proper system function, the details of which are
shown in the table.
No.
1
Options
High Speed System Oscillator Selection
fH – HXT or HIRC
Application Circuits
V
D D
0 .0 1 F * *
V D D
A N 0 ~ A N 9
P A 0 ~ P A 7
P B 0 ~ P B 5
0 .1 F
P C 0 ~ P C 7
P D 0 ~ P D 7
P E 0 ~ P E 7
V S S
P F 4 ~ P F 7
S E G 0 ~ S E G 1 9
X T 1
O S C
C ir c u it
X T 2
C O M 0 ~ C O M 7
T X
R X
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TinyPowerTM A/D 8-Bit Flash MCU with LCD & EEPROM
Instruction Set
Instruction
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 Holtekmicrocontrollers, 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 several 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 such as 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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TinyPower
TM
HT67F488/HT67F489
A/D 8-Bit Flash MCU with LCD & EEPROM
Logical and Rotate Operations
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
where 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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HT67F488/HT67F489
TinyPowerTM A/D 8-Bit Flash MCU with LCD & EEPROM
Instruction Set Summary
The instructions related to the data memory access in the following table can be used when the
desired data memory is located in Data Memory section 0.
Table Conventions
x: Bits immediate data
m: Data Memory address
A: Accumulator
i: 0~7 number of bits
addr: Program memory address
Mnemonic
Description
Cycles
Flag Affected
Add Data Memory to ACC
Add ACC to Data Memory
Add immediate data to ACC
Add Data Memory to ACC with Carry
Add ACC to Data memory with Carry
Subtract immediate data from the ACC
Subtract Data Memory from ACC
Subtract Data Memory from ACC with result in Data Memory
Subtract immediate data from ACC with Carry
Subtract Data Memory from ACC with Carry, 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, SC
Z, C, AC, OV, SC
Z, C, AC, OV, SC
Z, C, AC, OV, SC
Z, C, AC, OV, SC
Z, C, AC, OV, SC, CZ
Z, C, AC, OV, SC, CZ
Z, C, AC, OV, SC, CZ
Z, C, AC, OV, SC, CZ
Z, C, AC, OV, SC, CZ
C
1
1
1
1Note
1Note
1Note
1
1
1
1Note
1
Z
Z
Z
Z
Z
Z
Z
Z
Z
Z
Z
Increment Data Memory with result in ACC
Increment Data Memory
Decrement Data Memory with result in ACC
Decrement Data Memory
1
1Note
1
1Note
Z
Z
Z
Z
Rotate Data Memory right with result in ACC
Rotate Data Memory right
Rotate Data Memory right through Carry with result in ACC
Rotate Data Memory right through Carry
Rotate Data Memory left with result in ACC
Rotate Data Memory left
Rotate Data Memory left through Carry with result in ACC
Rotate Data Memory left through Carry
1
1Note
1
1Note
1
1Note
1
1Note
None
None
C
C
None
None
C
C
Arithmetic
ADD A,[m]
ADDM A,[m]
ADD A,x
ADC A,[m]
ADCM A,[m]
SUB A,x
SUB A,[m]
SUBM A,[m]
SBC A,x
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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TinyPower
TM
Mnemonic
HT67F488/HT67F489
A/D 8-Bit Flash MCU with LCD & EEPROM
Description
Cycles Flag Affected
Data Move
MOV A,[m]
MOV [m],A
MOV A,x
Move Data Memory to ACC
Move ACC to Data Memory
Move immediate data to ACC
1
1Note
1
None
None
None
Clear bit of Data Memory
Set bit of Data Memory
1Note
1Note
None
None
Jump unconditionally
Skip if Data Memory is zero
Skip if Data Memory is zero with data movement to ACC
Skip if bit i of Data Memory is zero
Skip if Data Memory is not zero
Skip if 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
2Note
2Note
2Note
None
None
None
2Note
None
1
1Note
1Note
1
1Note
1
1
None
None
None
TO, PDF
None
None
TO, PDF
Bit Operation
CLR [m].i
SET [m].i
Branch
JMP addr
SZ [m]
SZA [m]
SZ [m].i
SNZ [m]
SIZ [m]
SDZ [m]
SIZA [m]
SDZA [m]
CALL addr
RET
RET A,x
RETI
Table Read
TABRD [m] Read table to TBLH and Data Memory
TABRDL [m] Read table (last page) to TBLH and Data Memory
ITABRD [m] Increment table pointer TBLP first and Read table to TBLH and Data Memory
Increment table pointer TBLP first and Read table (last page) to TBLH and
ITABRDL [m]
Data Memory
Miscellaneous
NOP
CLR [m]
SET [m]
CLR WDT
SWAP [m]
SWAPA [m]
HALT
No operation
Clear Data Memory
Set Data Memory
Clear Watchdog Timer
Swap nibbles of Data Memory
Swap nibbles of Data Memory with result in ACC
Enter power down mode
Note: 1. For skip instructions, if the result of the comparison involves a skip then up to three cycles are required, if
no skip takes place only one cycle is required.
2. Any instruction which changes the contents of the PCL will also require 2 cycles for execution.
3. For the “CLR WDT” instruction the TO and PDF flags may be affected by the execution status. The TO
and PDF flags are cleared after the “CLR WDT” instructions is executed. Otherwise the TO and PDF
flags remain unchanged.
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TinyPowerTM A/D 8-Bit Flash MCU with LCD & 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, SC
ADCM A,[m]
Description
Operation
Affected flag(s)
Add ACC to Data Memory with Carry
The contents of the specified Data Memory, Accumulator and the carry flag are added. The result is stored in the specified Data Memory.
[m] ← ACC + [m] + C
OV, Z, AC, C, SC
Add Data Memory to ACC
ADD A,[m]
Description
The contents of the specified Data Memory and the Accumulator are added.
The result is stored in the Accumulator.
Operation
Affected flag(s)
ACC ← ACC + [m]
OV, Z, AC, C, SC
ADD A,x
Description
Operation
Affected flag(s)
Add immediate data to ACC
The contents of the Accumulator and the specified immediate data are added. The result is stored in the Accumulator.
ACC ← ACC + x
OV, Z, AC, C, SC
ADDM A,[m]
Description
Operation
Affected flag(s)
Add ACC to Data Memory
The contents of the specified Data Memory and the Accumulator are added. The result is stored in the specified Data Memory.
[m] ← ACC + [m]
OV, Z, AC, C, SC
AND A,[m]
Description
Operation
Affected flag(s)
Logical AND Data Memory to ACC
Data in the Accumulator and the specified Data Memory perform a bitwise logical AND operation. The result is stored in the Accumulator.
ACC ← ACC ″AND″ [m]
Z
AND A,x
Description
Operation
Affected flag(s)
Logical AND immediate data to ACC
Data in the Accumulator and the specified immediate data perform a bit wise logical AND operation. The result is stored in the Accumulator.
ACC ← ACC ″AND″ x
Z
ANDM A,[m]
Description
Operation
Affected flag(s)
Logical AND ACC to Data Memory
Data in the specified Data Memory and the Accumulator perform a bitwise logical AND
operation. The result is stored in the Data Memory.
[m] ← ACC ″AND″ [m]
Z
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TinyPower
TM
HT67F488/HT67F489
A/D 8-Bit Flash MCU with LCD & 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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TinyPowerTM A/D 8-Bit Flash MCU with LCD & 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
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TinyPower
TM
HT67F488/HT67F489
A/D 8-Bit Flash MCU with LCD & 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
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TinyPowerTM A/D 8-Bit Flash MCU with LCD & 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
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TM
HT67F488/HT67F489
A/D 8-Bit Flash MCU with LCD & 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, SC, CZ
SBC A, x
Description
Operation
Affected flag(s)
Subtract immediate data from ACC with Carry
The immediate data and the complement of the carry flag are subtracted from the Accumulator. The result is stored in the Accumulator. Note that if the result of subtraction is negative, the C flag will be cleared to 0, otherwise if the result is positive or zero, the C flag will be set to 1.
ACC ← ACC - [m] - C
OV, Z, AC, C, SC, CZ
SBCM A,[m]
Description
Operation
Affected flag(s)
Subtract Data Memory from ACC with Carry and result in Data Memory
The contents of the specified Data Memory and the complement of the carry flag are subtracted from the Accumulator. The result is stored in the Data Memory. Note that if the result of subtraction is negative, the C flag will be cleared to 0, otherwise if the result is positive or zero, the C flag will be set to 1.
[m] ← ACC − [m] − C
OV, Z, AC, C, SC, CZ
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TinyPowerTM A/D 8-Bit Flash MCU with LCD & EEPROM
SDZ [m]
Description
Operation
Affected flag(s)
Skip if decrement Data Memory is 0
The contents of the specified Data Memory are first decremented by 1. If the result is 0 the following instruction is skipped. As this requires the insertion of a dummy instruction while the next instruction is fetched, it is a two cycle instruction. If the result is not 0 the program proceeds with the following instruction.
[m] ← [m] − 1
Skip if [m]=0
None
SDZA [m]
Description
Operation
Affected flag(s)
Skip if decrement Data Memory is zero with result in ACC
The contents of the specified Data Memory are first decremented by 1. If the result is 0, the following instruction is skipped. The result is stored in the Accumulator but the specified Data Memory contents remain unchanged. As this requires the insertion of a dummy
instruction while the next instruction is fetched, it is a two cycle instruction. If the result is not 0,
the program proceeds with the following instruction.
ACC ← [m] − 1
Skip if ACC=0
None
SET [m]
Description
Operation
Affected flag(s)
Set Data Memory
Each bit of the specified Data Memory is set to 1.
[m] ← FFH
None
SET [m].i
Description
Operation
Affected flag(s)
Set bit of Data Memory
Bit i of the specified Data Memory is set to 1.
[m].i ← 1
None
SIZ [m]
Description
Operation
Affected flag(s)
Skip if increment Data Memory is 0
The contents of the specified Data Memory are first incremented by 1. If the result is 0, the
following instruction is skipped. As this requires the insertion of a dummy instruction while the next instruction is fetched, it is a two cycle instruction. If the result is not 0 the program
proceeds with the following instruction.
[m] ← [m] + 1
Skip if [m]=0
None
SIZA [m]
Description
Operation
Affected flag(s)
Skip if increment Data Memory is zero with result in ACC
The contents of the specified Data Memory are first incremented by 1. If the result is 0, the following instruction is skipped. The result is stored in the Accumulator but the specified
Data Memory contents remain unchanged. As this requires the insertion of a dummy
instruction while the next instruction is fetched, it is a two cycle instruction. If the result is not
0 the program proceeds with the following instruction.
ACC ← [m] + 1
Skip if ACC=0
None
SNZ [m].i
Description
Operation
Affected flag(s)
Skip if Data Memory is not 0
If the specified Data Memory is not 0, the following instruction is skipped. As this requires the
insertion of a dummy instruction while the next instruction is fetched, it is a two cycle instruction. If the result is 0 the program proceeds with the following instruction.
Skip if [m].i ≠ 0
None
Rev. 1.50
155
August 13, 2014
TinyPower
TM
HT67F488/HT67F489
A/D 8-Bit Flash MCU with LCD & EEPROM
SNZ [m]
Description
Operation
Affected flag(s)
Skip if Data Memory is not 0
If the specified Data Memory is not 0, the following instruction is skipped. As this requires the
insertion of a dummy instruction while the next instruction is fetched, it is a two cycle instruction. If the result is 0 the program proceeds with the following instruction.
Skip if [m]≠ 0
None
SUB A,[m]
Description
Operation
Affected flag(s)
Subtract Data Memory from ACC
The specified Data Memory is subtracted from the contents of the Accumulator. The result is stored in the Accumulator. Note that if the result of subtraction is negative, the C flag will be cleared to 0, otherwise if the result is positive or zero, the C flag will be set to 1.
ACC ← ACC − [m]
OV, Z, AC, C, SC, CZ
SUBM A,[m]
Description
Operation
Affected flag(s)
Subtract Data Memory from ACC with result in Data Memory
The specified Data Memory is subtracted from the contents of the Accumulator. The result is stored in the Data Memory. Note that if the result of subtraction is negative, the C flag will be cleared to 0, otherwise if the result is positive or zero, the C flag will be set to 1.
[m] ← ACC − [m]
OV, Z, AC, C, SC, CZ
SUB A,x
Description
Operation
Affected flag(s)
Subtract immediate data from ACC
The immediate data specified by the code is subtracted from the contents of the Accumulator. The result is stored in the Accumulator. Note that if the result of subtraction is negative, the C flag will be cleared to 0, otherwise if the result is positive or zero, the C flag will be set to 1.
ACC ← ACC − x
OV, Z, AC, C, SC, CZ
SWAP [m]
Description
Operation
Affected flag(s)
Swap nibbles of Data Memory
The low-order and high-order nibbles of the specified Data Memory are interchanged.
[m].3~[m].0 ↔ [m].7~[m].4
None
SWAPA [m]
Description
Operation
Affected flag(s)
Swap nibbles of Data Memory with result in ACC
The low-order and high-order nibbles of the specified Data Memory are interchanged. The result is stored in the Accumulator. The contents of the Data Memory remain unchanged.
ACC.3~ACC.0 ← [m].7~[m].4
ACC.7~ACC.4 ← [m].3~[m].0
None
SZ [m]
Description
Operation
Affected flag(s)
Skip if Data Memory is 0
If the contents of the specified Data Memory is 0, the following instruction is skipped. As this requires the insertion of a dummy instruction while the next instruction is fetched, it is a two cycle instruction. If the result is not 0 the program proceeds with the following instruction.
Skip if [m]=0
None
Rev. 1.50
156
August 13, 2014
HT67F488/HT67F489
TinyPowerTM A/D 8-Bit Flash MCU with LCD & EEPROM
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
TABRD [m]
Description
Operation
Affected flag(s)
Read table (current page) to TBLH and Data Memory
The low byte of the program code (current page) addressed by the table pointer (TBLP) is moved to the specified Data Memory and the high byte moved to TBLH.
[m] ← program code (low byte)
TBLH ← program code (high byte)
None
TABRDL [m]
Description
Operation
Affected flag(s)
Read table (last page) to TBLH and Data Memory
The low byte of the program code (last page) addressed by the table pointer (TBLP) is moved to the specified Data Memory and the high byte moved to TBLH.
[m] ← program code (low byte)
TBLH ← program code (high byte)
None
ITABRD [m]
Description
Operation
Affected flag(s)
Increment table pointer low byte first and read table to TBLH and Data Memory
Increment table pointer low byte, TBLP, first and then the program code addressed by the table pointer (TBHP and TBLP) is moved to the specified Data Memory and the high byte moved to TBLH.
[m] ← program code (low byte)
TBLH ← program code (high byte)
None
ITABRDL [m]
Description
Operation
Affected flag(s)
Increment table pointer low byte first and read table (last page) to TBLH and Data Memory
Increment table pointer low byte, TBLP, first and then the low byte of the program code (last page) addressed by the table pointer (TBLP) is moved to the specified Data Memory and the high byte moved to TBLH.
[m] ← program code (low byte)
TBLH ← program code (high byte)
None
XOR A,[m]
Description
Operation
Affected flag(s)
Logical XOR Data Memory to ACC
Data in the Accumulator and the specified Data Memory perform a bitwise logical XOR operation. The result is stored in the Accumulator.
ACC ← ACC ″XOR″ [m]
Z
Rev. 1.50
157
August 13, 2014
TinyPower
TM
HT67F488/HT67F489
A/D 8-Bit Flash MCU with LCD & EEPROM
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. 1.50
158
August 13, 2014
HT67F488/HT67F489
TinyPowerTM A/D 8-Bit Flash MCU with LCD & 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. 1.50
159
August 13, 2014
TinyPower
TM
HT67F488/HT67F489
A/D 8-Bit Flash MCU with LCD & EEPROM
44-pin LQFP (10mm×10mm) (FP2.0mm) Outline Dimensions
Symbol
Nom.
Max.
A
—
0.472 BSC
—
B
—
0.394 BSC
—
C
—
0.472 BSC
—
D
—
0.394 BSC
—
E
—
0.032 BSC
—
F
0.012
0.015
0.018
G
0.053
0.055
0.057
H
—
—
0.063
I
0.002
—
0.006
J
0.018
0.024
0.030
K
0.004
—
0.008
α
0°
—
7°
Symbol
Rev. 1.50
Dimensions in inch
Min.
Dimensions in mm
Min.
Nom.
Max.
A
—
12.00 BSC
—
B
—
10.00 BSC
—
C
—
12.00 BSC
—
D
—
10.00 BSC
—
E
—
0.80 BSC
—
F
0.30
0.37
0.45
G
1.35
1.40
1.45
H
—
—
1.60
I
0.05
—
0.15
J
0.45
0.60
0.75
K
0.09
—
0.20
α
0°
—
7°
160
August 13, 2014
HT67F488/HT67F489
TinyPowerTM A/D 8-Bit Flash MCU with LCD & 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. 1.50
161
August 13, 2014