HT45F3820v100.pdf

Ultrasonic Humidifier 8-Bit Flash MCU
HT45F3820
Revision: V1.00
Date: ������������
May 30, 2016
HT45F3820
Ultrasonic Humidifier 8-Bit Flash MCU
Table of Contents
Features............................................................................................................. 6
CPU Features.......................................................................................................................... 6
Peripheral Features.................................................................................................................. 6
General Description ......................................................................................... 7
Block Diagram................................................................................................... 8
Pin Assignment................................................................................................. 8
Pin Descriptions............................................................................................... 9
Absolute Maximum Ratings........................................................................... 10
D.C. Characteristics........................................................................................ 10
A.C. Characteristics........................................................................................ 12
LVD & LVR Electrical Characteristics........................................................... 13
Over Current / Voltage Protection Electrical Characteristics..................... 14
Power on Reset Electrical Characteristics................................................... 15
System Architecture....................................................................................... 15
Clocking and Pipelining.......................................................................................................... 15
Program Counter.................................................................................................................... 16
Stack...................................................................................................................................... 17
Arithmetic and Logic Unit – ALU............................................................................................ 17
Flash Program Memory.................................................................................. 18
Structure................................................................................................................................. 18
Special Vectors...................................................................................................................... 18
Look-up Table......................................................................................................................... 18
Table Program Example......................................................................................................... 19
In Circuit Programming.......................................................................................................... 20
On-Chip Debug Support – OCDS.......................................................................................... 20
RAM Data Memory.......................................................................................... 21
Structure................................................................................................................................. 21
General Purpose Data Memory............................................................................................. 21
Special Purpose Data Memory.............................................................................................. 22
Special Function Register Description......................................................... 23
Indirect Addressing Registers – IAR0, IAR1.......................................................................... 23
Memory Pointers – MP0, MP1............................................................................................... 23
Bank Pointer – BP.................................................................................................................. 24
Accumulator – ACC................................................................................................................ 24
Program Counter Low Register – PCL................................................................................... 24
Look-up Table Registers – TBLP, TBHP, TBLH...................................................................... 25
Status Register – STATUS..................................................................................................... 25
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May 30, 2016
HT45F3820
Ultrasonic Humidifier 8-Bit Flash MCU
EEPROM Data Memory................................................................................... 27
EEPROM Data Memory Structure......................................................................................... 27
EEPROM Registers............................................................................................................... 27
Reading Data from the EEPROM ......................................................................................... 29
Writing Data to the EEPROM................................................................................................. 29
Write Protection...................................................................................................................... 29
EEPROM Interrupt................................................................................................................. 29
Programming Considerations................................................................................................. 30
Oscillators....................................................................................................... 31
Oscillator Overview................................................................................................................ 31
System Clock Configurations................................................................................................. 31
Internal RC Oscillator – HIRC................................................................................................ 32
Internal 32kHz Oscillator – LIRC............................................................................................ 32
Operating Modes and System Clocks.......................................................... 33
System Clocks....................................................................................................................... 33
System Operating Modes....................................................................................................... 34
Control Registers................................................................................................................... 35
Operating Mode Switching .................................................................................................... 37
Standby Current Considerations............................................................................................ 41
Wake-up................................................................................................................................. 41
Watchdog Timer.............................................................................................. 42
Watchdog Timer Clock Source............................................................................................... 42
Watchdog Timer Control Register.......................................................................................... 42
Watchdog Timer Operation.................................................................................................... 43
Reset and Initialisation................................................................................... 45
Reset Functions..................................................................................................................... 45
Reset Initial Conditions.......................................................................................................... 47
Input/Output Ports.......................................................................................... 49
Pull-high Resistors................................................................................................................. 50
Port A Wake-up...................................................................................................................... 50
I/O Port Control Registers...................................................................................................... 51
I/O Port Source Current Control............................................................................................. 51
I/O Port Output Slew Rate Control......................................................................................... 52
Pin-shared Function............................................................................................................... 52
I/O Pin Structures................................................................................................................... 54
Programming Considerations................................................................................................. 54
Timer Modules – TM....................................................................................... 55
Introduction............................................................................................................................ 55
TM Operation......................................................................................................................... 55
TM Clock Source.................................................................................................................... 55
TM Interrupts.......................................................................................................................... 56
TM External Pins.................................................................................................................... 56
TM Input/Output Pin Control Register.................................................................................... 56
Programming Considerations................................................................................................. 57
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HT45F3820
Ultrasonic Humidifier 8-Bit Flash MCU
Standard Type TM – STM............................................................................... 58
Standard TM Operation.......................................................................................................... 58
Standard Type TM Register Description................................................................................ 58
Standard Type TM Operating Modes..................................................................................... 62
Periodic Type TM – PTM................................................................................. 71
Periodic TM Operation .......................................................................................................... 71
Periodic Type TM Register Description ................................................................................. 71
Periodic Type TM Operating Modes ...................................................................................... 76
Nebuliser Resonance Detector...................................................................... 85
Water Shortage Protection............................................................................. 85
Over Current/Voltage Protection................................................................... 85
OCVP Operation.................................................................................................................... 85
OCVP Control Registers........................................................................................................ 86
Input Voltage Range............................................................................................................... 90
Offset Calibration................................................................................................................... 90
Interrupts......................................................................................................... 91
Interrupt Registers.................................................................................................................. 91
Interrupt Operation................................................................................................................. 96
External Interrupts.................................................................................................................. 97
OCVP Interrupt....................................................................................................................... 98
Multi-function Interrupts.......................................................................................................... 98
Time Base Interrupts.............................................................................................................. 98
EEPROM Interrupt............................................................................................................... 100
LVD Interrupt........................................................................................................................ 100
TM Interrupts........................................................................................................................ 100
Interrupt Wake-up Function.................................................................................................. 101
Programming Considerations............................................................................................... 101
Low Voltage Detector – LVD........................................................................ 102
LVD Register........................................................................................................................ 102
LVD Operation...................................................................................................................... 103
Configuration Options.................................................................................. 103
Application Circuits...................................................................................... 104
Instruction Set............................................................................................... 105
Introduction.......................................................................................................................... 105
Instruction Timing................................................................................................................. 105
Moving and Transferring Data.............................................................................................. 105
Arithmetic Operations........................................................................................................... 105
Logical and Rotate Operation.............................................................................................. 106
Branches and Control Transfer............................................................................................ 106
Bit Operations...................................................................................................................... 106
Table Read Operations........................................................................................................ 106
Other Operations.................................................................................................................. 106
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May 30, 2016
HT45F3820
Ultrasonic Humidifier 8-Bit Flash MCU
Instruction Set Summary............................................................................. 107
Table Conventions................................................................................................................ 107
Instruction Definition.................................................................................... 109
Package Information.....................................................................................118
8-pin SOP (150mil) Outline Dimensions...............................................................................119
10-pin SOP (150mil) Outline Dimensions............................................................................ 120
Rev. 1.00
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May 30, 2016
HT45F3820
Ultrasonic Humidifier 8-Bit Flash MCU
Note that 8-pin MCU package types are not marketed in the following
countries: UK, Germany, The Netherlands, France and Italy.
Features
CPU Features
• Operating Voltage:
♦♦
fSYS=12MHz: 2.7V ~ 5.5V
♦♦
fSYS=32kHz: 2.2V ~ 5.5V
• Up to 0.33μs instruction cycle with 12MHz system clock at VDD=5V
• Power down and wake-up functions to reduce power consumption
• Oscillators:
♦♦
Internal High Speed RC – HIRC
♦♦
Internal Low Speed 32kHz RC – LIRC
• Multi-mode operation: NORMAL, SLOW, IDLE and SLEEP
• All instructions executed in one or two instruction cycles
• Table read instructions
• 63 powerful instructions
• 4-level subroutine nesting
• Bit manipulation instruction
Peripheral Features
• Flash Program Memory: 1K×16
• RAM Data Memory: 64×8
• EEPROM Memory: 32×8
• Watchdog Timer function
• 8 bidirectional I/O lines
• Two pin-shared external interrupts
• Multiple Timer Modules for time measure, input capture, compare match output, PWM output
function or single pulse output function
♦♦
10-bit PTM × 1
♦♦
10-bit STM × 1
• Over Current/Voltage Protection (OCVP) Function with interrupt
• Dual Time-Base functions for generation of fixed time interrupt signals
• Low voltage reset function
• Low voltage detect function
• Flash program memory can be re-programmed up to 100,000 times
• Flash program memory data retention > 10 years
• EEPROM data memory can be re-programmed up to 1,000,000 times
• EEPROM data memory data retention > 10 years
• Package Types: 8-pin SOP/10-pin SOP
Rev. 1.00
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May 30, 2016
HT45F3820
Ultrasonic Humidifier 8-Bit Flash MCU
General Description
The HT45F3820 is a device dedicated for use in ultrasonic nebuliser applications. The application
principle for ultrasonic nebulisers is to use electronic high-frequency oscillation and ceramic
nebulising chip high-frequency resonance to break up the liquid water molecules thus generating
a fine mist without requiring heating or any chemical substances. Compared with the heating
nebulisation method, the ultrasonic method can result in 90% energy savings. Additionally, during
the nebulisation process, it can release a large number of negative ions which can precipitate smoke
and dust particles in air by electrostatic reaction and also can effectively remove formaldehyde,
carbon monoxide, bacteria and other harmful substances thus generating cleaner air and reducing the
possibility of disease transmission.
The device is a Flash Memory type 8-bit high performance RISC architecture microcontroller
containing special internal circuitry for ultrasonic nebuliser applications. Offering users the convenience
of Flash Memory multi-programming features, this device also includes a wide range of functions
and features. Other memory includes an area of RAM Data Memory as well as an area of EEPROM
memory for storage of non-volatile data such as serial numbers, calibration data etc. Analog feature
includes an over current/voltage protection 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.
The device also includes fully integrated low and high speed oscillators which can be flexibly
used for different applications. The ability to operate and switch dynamically between a range of
operating modes using different clock sources gives users the ability to optimise microcontroller
operation and minimise power consumption.
While the inclusion of flexible I/O programming features, Time-Base functions along with an
adjustable ultrasonic nebuliser resonant frequency generator and many other features ensure that the
device will find excellent use in different ultrasonic nebuliser applications.
This device can use the nebuliser resonance detector to detect the nebuliser resonant frequency,
and use the nebuliser resonant frequency selection to output PFM resonant frequency for nebuliser
control, it can also use the water shortage protection and OCVP functions for water shortage
detection.
Rev. 1.00
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May 30, 2016
HT45F3820
Ultrasonic Humidifier 8-Bit Flash MCU
Block Diagram
Flash/EEPROM
Programming Circuitry
EEPROM
Data
Memory
Flash
Program
Memory
Watchdog
Timer
Low
Voltage
Detect
8-bit
RISC
MCU
Core
Low
Voltage
Reset
RAM
Data
Memory
Reset
Circuit
Interrupt
Controller
Internal RC
Oscillators
Time
Base
Nebuliser Resonant Slew Rate
Frequency Selection Controller
I/O
Nebuliser Resonance
Detector & Water Shortage
Protection
Timer
Modules
Over Current/Voltage
Protection
OCVPS[1:0]
Pin Assignment
PTP/PA1
1
8
VSS
�
7
PA0/ICPDA/OCDSDA
PA�/ICPCK/OCDSCK
VDD
�
�
OCVPAI0/STP/PA4/VREF
OCVPAI0/INT0/PTCK/PA�
4
5
OCVPCI/INT1/STCK/PA5
HT45F3820
8 SOP-A
OCVPAI0/PA�
PTP/PA1
1
10
VSS
VDD
�
9
PA0/ICPDA/OCDSDA
�
8
OCVPAI0/PA7
4
7
PA�/ICPCK/OCDSCK
OCVPAI0/STP/PA4/VREF
OCVPAI0/INT0/PTCK/PA�
5
�
OCVPCI/INT1/STCK/PA5
HT45F3820
10 SOP-A
PTP/PA1
1
1�
OCVP0AI0/PA�
VSS
�
15
PA0/ICPDA
VDD
OCVPAI0/PA7
�
14
PA�/ICPCK
4
1�
OCVPAI0/STP/PA4/VREF
OCVPAI0/INT0/PTCK/PA�
5
1�
NC
�
11
NC
7
10
OCVPCI/INT1/STCK/PA5
NC
NC
OCDSCK
8
9
OCDSDA
HT45V3820
16 SOP-A
Note: 1. If the pin-shared pin functions have multiple output functions, the desired pin-shared function is determined
using corresponding software control bits.
2. The actual device and its equivalent OCDS EV device share the same package type, however the OCDS
EV device part number is HT45V3820. Pins OCDSCK and OCDSDA which are pin-shared with PA2
and PA0 are only used for the OCDS EV device.
Rev. 1.00
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May 30, 2016
HT45F3820
Ultrasonic Humidifier 8-Bit Flash MCU
Pin Descriptions
With the exception of the power pins, all pins on this device can be referenced to by their Port name,
e.g. PA0, PA1 etc, which refer to the digital I/O function of the pins. However these Port pins are
also shared with other function such as Timer Module pins etc. The function of each pin is listed
in the following table, however the details behind how each pin is configured is contained in other
sections of the datasheet.
Pin Name
PA0/ ICPDA/
OCDSDA
PTP/PA1
PA2/ ICPCK/
OCDSCK
OCVPAI0/INT0/
PTCK/PA3
OCVPAI0/STP/
VREF/PA4
OCVPCI/INT1/
STCK/PA5
Function
OPT
PA0
PAPU
PAWU
ST
General purpose I/O. Register enabled pull-up and
CMOS
wake-up.
ICPDA
—
ST
CMOS In-circuit programming data/address pin
OCDSDA
—
ST
CMOS
On-chip debug support data/address pin, for EV chip
only
PA1
PAPU
PAWU
CTRL3
ST
CMOS
General purpose I/O. Register enabled pull-up and
wake-up.
PTP
CTRL3
ST
CMOS PTM output
PA2
PAPU
PAWU
ST
CMOS
O/T
Description
General purpose I/O. Register enabled pull-up and
wake-up.
ICPCK
—
ST
—
In-circuit programming clock pin
OCDSCK
—
ST
—
On-chip debug support clock pin, for EV chip only
PA3
PAPU
PAWU
CTRL3
ST
CMOS
General purpose I/O. Register enabled pull-up and
wake-up.
OCVPAI0
CTRL2
CTRL3
ST
—
OCVPAI0 input path 0
INT0
CTRL3
INTEG
ST
—
External interrupt 0
PTCK
CTRL3
PTMC0
ST
—
PTM clock input
PA4
PAPU
PAWU
CTRL3
ST
CMOS
CMOS STM output or capture input
General purpose I/O. Register enabled pull-up and
wake-up.
STP
CTRL3
ST
VREF
CTRL3
AN
—
DAC Voltage reference
OCVPAI0
CTRL2
CTRL3
ST
—
OCVPAI0 input path 0, nebuliser resonance detector
& water shortage protection
PA5
PAPU
PAWU
CTRL3
ST
CMOS
OCVPCI
CTRL3
AN
—
Comparator non-inverted signal input
INT1
CTRL3
INTEG
ST
—
External interrupt 1
STCK
CTRL3
STMC0
ST
—
STM clock input
PA6
PAPU
PAWU
ST
CMOS
OCVPAI0
CTRL2
CTRL3
ST
—
PA7
PAPU
PAWU
ST
CMOS
OCVPAI0
CTRL2
CTRL3
ST
—
OCVPAI0/PA6
OCVPAI0/PA7
Rev. 1.00
I/T
9
General purpose I/O. Register enabled pull-up and
wake-up.
General purpose I/O. Register enabled pull-up and
wake-up.
OCVPAI0 input path 0
General purpose I/O. Register enabled pull-up and
wake-up.
OCVPAI0 input path 0
May 30, 2016
HT45F3820
Ultrasonic Humidifier 8-Bit Flash MCU
Function
OPT
I/T
O/T
VDD
Pin Name
VDD
—
PWR
—
Positive power supply
Description
VSS
VSS
—
PWR
—
Negative Power Supply
Legend: I/T: Input type
O/T: Output type
OPT: Optional by register option
PWR: Power
ST: Schmitt Trigger input
CMOS: CMOS output
Absolute Maximum Ratings
Supply Voltage.................................................................................................VSS−0.3V to VSS+6.0V
Input Voltage...................................................................................................VSS−0.3V to VDD+0.3V
Storage Temperature.....................................................................................................-50˚C to 125˚C
Operating Temperature...................................................................................................-40˚C to 85˚C
IOL Total...................................................................................................................................... 80mA
IOH 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
Parameter
VDD
Conditions
Typ.
Max.
Unit
Operating Voltage (HIRC)
—
fSYS=fHIRC=12MHz
2.7
—
5.5
V
—
fSYS=fLIRC=32kHz
2.2
—
5.5
V
3V
No load, all peripherals off,
fSYS=fHIRC=12MHz
—
2.2
3.3
mA
—
5
7.5
mA
No load, all peripherals off,
fSYS=fLIRC=32kHz
—
10
20
μA
—
30
50
μA
No load, all peripherals off,
WDT off
—
0.2
0.8
μA
—
0.5
1
μA
No load, all peripherals off,
WDT on
—
1.3
5
μA
—
2.2
10
μA
No load, all peripherals off,
fSUB on
—
1.3
3
μA
—
2.2
5
μA
No load, all peripherals off,
fSUB on, fSYS=fHIRC=12MHz
—
0.6
1.2
mA
—
1.2
2.4
mA
0
—
1.5
V
0
—
0.2
VDD
V
IDD
Operating Current (LIRC)
5V
3V
5V
3V
Standby Current (SLEEP0
Mode)
5V
Standby Current (SLEEP1
Mode)
5V
Standby Current (IDLE0 Mode)
Standby Current (IDLE1 Mode,
HIRC)
3V
3V
5V
3V
5V
5V
VIL
Input Low Voltage for I/O Ports
VIH
Input High Voltage for I/O Ports
Rev. 1.00
Min.
Operating Voltage (LIRC)
Operating Current (HIRC)
ISTB
Test Conditions
—
—
—
5V
—
3.5
—
5
V
—
0.8
VDD
—
VDD
V
—
10
May 30, 2016
HT45F3820
Ultrasonic Humidifier 8-Bit Flash MCU
Symbol
IOL
IOH
Parameter
Sink Current for I/O Ports
(PA7~PA2, PA0)
Sink current for PA1 With Slew
Rate Control
Source Current for I/O Ports
(PA7~PA2, PA0)
Source current for PA1 With
Slew Rate Control
SRRISE
SRFALL
RPH
Rev. 1.00
Test Conditions
VDD
Min.
Typ.
Max.
Unit
3V
VOL=0.1VDD
16
32
—
mA
5V
VOL=0.1VDD
32
65
—
mA
3V
VOL=0.2VDD
24
60
—
mA
5V
VOL=0.2VDD
60
150
—
mA
3V
VOH=0.9VDD, SLEDC[m+1, m]=00B
(m=0 or 2 or 4 or 6)
-0.7
-1.5
—
mA
5V
VOH=0.9VDD, SLEDC[m+1, m]=00B
(m=0 or 2 or 4 or 6)
-1.5
-2.9
—
mA
3V
VOH=0.9VDD, SLEDC[m+1, m]=01B
(m=0 or 2 or 4 or 6)
-1.3
-2.5
—
mA
5V
VOH=0.9VDD, SLEDC[m+1, m]=01B
(m=0 or 2 or 4 or 6)
-2.5
-5.1
—
mA
3V
VOH=0.9VDD, SLEDC[m+1, m]=10B
(m=0 or 2 or 4 or 6)
-1.8
-3.6
—
mA
5V
VOH=0.9VDD, SLEDC[m+1, m]=10B
(m=0 or 2 or 4 or 6)
-3.6
-7.3
—
mA
3V
VOH=0.9VDD, SLEDC[m+1, m]=11B
(m=0 or 2 or 4 or 6)
-4
-8
—
mA
5V
VOH=0.9VDD, SLEDC[m+1, m]=11B
(m=0 or 2 or 4 or 6)
-8
-16
—
mA
3V
VOH=0.8VDD
-24
-60
—
mA
5V
VOH=0.8VDD
-60
-150
—
mA
5V
SLEWC[m+1, m]=00B
(m=0 or 2 or 4 or 6), 0.5V ~ 4.5V,
CLOAD=1000pF
200
—
—
V/μs
5V
SLEWC[m+1, m]=01B
(m=0 or 2 or 4 or 6), 0.5V ~ 4.5V,
CLOAD=1000pF
—
60
—
V/μs
5V
SLEWC[m+1, m]=10B
(m=0 or 2 or 4 or 6), 0.5V ~ 4.5V,
CLOAD=1000pF
—
30
—
V/μs
5V
SLEWC[m+1, m]=11B
(m=0 or 2 or 4 or 6), 0.5V ~ 4.5V,
CLOAD=1000pF
—
15
—
V/μs
5V
SLEWC[m+1, m]=00B
(m=0 or 2 or 4 or 6), 4.5V ~ 0.5V,
CLOAD=1000pF
200
—
—
V/μs
5V
SLEWC[m+1, m]=01B
(m=0 or 2 or 4 or 6), 4.5V ~ 0.5V,
CLOAD=1000pF
—
60
—
V/μs
5V
SLEWC[m+1, m]=10B
(m=0 or 2 or 4 or 6), 4.5V ~ 0.5V,
CLOAD=1000pF
—
30
—
V/μs
5V
SLEWC[m+1, m]=11B
(m=0 or 2 or 4 or 6), 4.5V ~ 0.5V,
CLOAD=1000pF
—
15
—
V/μs
3V
—
20
60
100
kΩ
5V
—
10
30
50
kΩ
Output Rising Edge Slew Rate
for PA1
Output Falling Edge Slew Rate
for PA1
Pull-high Resistance for I/O
Ports
Conditions
11
May 30, 2016
HT45F3820
Ultrasonic Humidifier 8-Bit Flash MCU
A.C. Characteristics
Ta=25°C
Symbol
fSYS
fHIRC
Parameter
Test Conditions
VDD
Conditions
Typ.
Max.
Unit
MHz
System Clock (HIRC)
2.7V ~ 5.5V fSYS=fHIRC=12MHz
—
12
—
System Clock (LIRC)
2.2V ~ 5.5V fSYS=fLIRC=32kHz
—
32
—
kHz
High Speed Internal RC
Oscillator (HIRC)
3V
Ta=25°C
-2%
12
+2%
MHz
5V
Ta=25°C
-2%
12
+2%
MHz
2.7V ~ 5.5V Ta=25°C
-5%
12
+5%
MHz
3V
Ta=0°C ~ 70°C
- 7%
12
+7%
MHz
5V
Ta=0°C ~ 70°C
- 7%
12
+7%
MHz
3V
Ta= -40°C ~ 85°C
-10%
12
+10% MHz
5V
Ta= -40°C ~ 85°C
-7%
12
+7%
MHz
2.7V ~ 5.5V Ta=0°C ~ 70°C
-7%
12
+7%
MHz
2.7V ~ 5.5V Ta= -40°C ~ 85°C
-10%
12
+10% MHz
Ta=25°C
-10%
32
+10%
kHz
Ta= -40°C ~ 85°C
-40%
32
+40%
kHz
3V
3V ± 0.3V
fLIRC
Min.
Low Speed Internal RC
Oscillator (LIRC)
2.2V ~ 5.5V Ta= -40°C ~ 85°C
-50%
32
+60%
kHz
Ta=25°C
-10%
32
+10%
kHz
Ta= -40°C ~ 85°C
-40%
32
+40%
kHz
2.2V ~ 5.5V Ta= -40°C ~ 85°C
-50%
32
+50%
kHz
5V
5V ± 0.5V
tINT
External Interrupt Minimum
Pulse Width
—
—
1
3.3
5
μs
tEERD
EEPROM Read Time
—
—
—
2
4
tSYS
tEEWR
EEPROM Write Time
—
—
—
2
4
ms
—
—
25
50
100
ms
tRSTD
System Reset Delay Time
(Power-on Reset, LVR Hardware
Reset, LVR Software Reset,
WDT Software Reset)
System reset delay time
(WDT Time-out Hardware Cold
Reset)
—
—
8.3
16.7
33.3
ms
System Start-up Timer Period
(Wake-up from Power Down
Mode and fSYS off)
System Start-up Timer Period
(Slow Mode ↔ Normal Mode)
tSST
System Start-up Timer Period
(Wake-up from Power Down
Mode and fSYS on)
System Start-up Timer Period
(WDT Time-out Hardware Cold
Reset)
—
fSYS=fH ~ fH / 64, fH=fHIRC
16
—
—
tHIRC
—
fSYS=fSUB=fLIRC
2
—
—
tLIRC
—
fHIRC off → on (HTO=1)
16
—
—
tHIRC
—
fSYS=fHIRC ~ fHIRC /64
2
—
—
tH
—
fSYS=fLIRC
2
—
—
tSUB
0
—
—
tH
—
—
Note: 1. tSYS=1/fSYS; tSUB=1/fSUB; tHIRC=1/fHIRC
2. To maintain the accuracy of the internal HIRC oscillator frequency, a 0.1μF decoupling capacitor should
be connected between VDD and VSS and located as close to the device as possible.
3. Frequency accuracy (trim at VDD=3V/5V, FADJH=01H, FADJL=00H).
Rev. 1.00
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HT45F3820
Ultrasonic Humidifier 8-Bit Flash MCU
LVD & LVR Electrical Characteristics
Ta=25°C
Symbol
VLVR
VLVD
Parameter
Low Voltage Reset Voltage
Low Voltage Detector Voltage
ILVR
Additional PowerConsumption
if LVR is used
ILVD
Additional PowerConsumption
if LVD is used
Test Conditions
VDD
—
Conditions
Min.
Typ.
Max.
Unit
LVR enable, 2.1V
2.1
V
LVR enable, 2.55V
2.55
V
LVR enable, 3.15V
-5%
3.15
+5%
V
LVR enable, 3.8V
3.8
V
—
LVDEN=1, VLVD=2.0V
2.0
V
—
LVDEN=1, VLVD=2.2V
2.2
V
—
LVDEN=1, VLVD=2.4V
2.4
V
—
LVDEN=1, VLVD=2.7V
2.7
—
LVDEN=1, VLVD=3.0V
—
LVDEN=1, VLVD=3.3V
3.3
—
LVDEN=1, VLVD=3.6V
3.6
V
—
LVDEN=1, VLVD=4.0V
4.0
V
-5%
3.0
+5%
V
V
V
5V±3% LVR disable → LVR enable
—
60
90
μA
LVD disable → LVD enable
(LVR disable)
—
75
115
μA
LVD disable → LVD enable
(LVR enable)
—
60
90
μA
5V±3%
tLVR
LVR Minimum Low Voltage
Width to Reset
—
—
120
240
480
μs
tLVD
LVD Minimum Low Voltage
Width to Interrupt
—
—
60
120
240
μs
tLVDS
LVDO Stable Time
tSRESET
Software Reset Width to Reset
—
For LVR enable, LVD off → on
—
—
15
μs
—
For LVR disable, LVD off → on
—
—
150
μs
45
90
120
μs
—
—
Note: VLVR or VLVD is the MCU operating voltage level under which a LVR reset or LVD interrupt occurs.
Rev. 1.00
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HT45F3820
Ultrasonic Humidifier 8-Bit Flash MCU
Over Current / Voltage Protection Electrical Characteristics
Ta=25°C
Symbol
IOCVP
VOS_CMP
VHYS
VCM_CMP
VOS_OPA
VCM_OPA
VOR
Ga
Parameter
Operating Current
Comparator Input Offset
Voltage
Hysteresis
Comparator Common Mode
Voltage Range
OPA Input Offset Voltage
OPA Common Mode Voltage
Range
OPA Maximum Output Voltage
Range
PGA Gain Accuracy
DNL
Differential Non-linearity
INL
Integral Non-linearity
Rev. 1.00
Test Conditions
Typ.
Max.
Unit
—
—
1250
μA
—
730
1250
μA
3V
Without calibration
(OCVPCOF[4:0]=10000B)
-15
—
15
mV
5V
Without calibration
(OCVPCOF[4:0]=10000B)
-15
—
15
mV
3V
With calibration
-4
—
4
mV
5V
With calibration
-4
—
4
mV
60
mV
VDD
3V
5V
Conditions
DAC VREF=2.5V
Min.
3V
—
20
40
5V
—
20
40
60
mV
V
3V
—
VSS
—
VDD
- 1.4
5V
—
VSS
—
VDD
- 1.4
V
3V
Without calibration
(OCVPOOF[5:0]=100000B)
-15
—
15
mV
5V
Without calibration
(OCVPOOF[5:0]=100000B)
-15
—
15
mV
3V
With calibration
-4
—
4
mV
5V
With calibration
-4
—
4
mV
V
3V
—
VSS
—
VDD
- 1.4
5V
—
VSS
—
VDD
- 1.4
V
3V
—
VSS
+ 0.1
—
VDD
- 0.1
V
5V
—
VSS
+ 0.1
—
VDD
- 0.1
V
In non-inverting mode, R2/R1≤50,
using internal resistor, and input
voltage > 80mV
-5
—
5
%
In non-inverting mode, R2/R1=65
or 80 , using internal resistor, and
input voltage > 50mV
-8
—
8
%
In non-inverting mode, R2/R1=130,
using internal resistor, and input
voltage > 35mV
-10
—
10
%
In inverting mode, R2/R1≤50,
using internal resistor, and input
voltage < -80mV
-5
—
5
%
In inverting mode, R2/R1=65 or 80,
using internal resistor, and input
voltage < -50mV
-8
—
8
%
In inverting mode, R2/R1=130,
using internal resistor, and input
voltage < -35mV
-10
—
10
%
3V
DAC VREF=VDD
—
—
±2
LSB
5V
DAC VREF=VDD
—
—
±1
LSB
3V
DAC VREF=VDD
—
—
±2
LSB
5V
DAC VREF=VDD
—
—
±1.5
LSB
3V/
5V
14
May 30, 2016
HT45F3820
Ultrasonic Humidifier 8-Bit Flash MCU
Power on Reset Electrical 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
RRPOR
VDD Rising 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
VDD
tPOR
RRPOR
VPOR
Time
System Architecture
A key factor in the high-performance features of the Holtek range of microcontrollers is attributed
to their internal system architecture. The device takes advantage of the usual features found within
RISC microcontrollers providing increased speed of operation and Periodic performance. The
pipelining scheme is implemented in such a way that instruction fetching and instruction execution
are overlapped, hence instructions are effectively executed in one cycle, with the exception of branch
or call instructions. An 8-bit wide ALU is used in practically all instruction set operations, which
carries out arithmetic operations, logic operations, rotation, increment, decrement, branch decisions,
etc. The internal data path is simplified by moving data through the Accumulator and the ALU.
Certain internal registers are implemented in the Data Memory and can be directly or indirectly
addressed. The simple addressing methods of these registers along with additional architectural
features ensure that a minimum of external components is required to provide a functional I/O
control system with maximum reliability and flexibility. This makes the device suitable for low-cost,
high-volume production for controller applications.
Clocking and Pipelining
The main system clock, derived from either an HIRC or LIRC oscillator is subdivided into four
internally generated non-overlapping clocks, T1~T4. The Program Counter is incremented at the
beginning of the T1 clock during which time a new instruction is fetched. The remaining T2~T4
clocks carry out the decoding and execution functions. In this way, one T1~T4 clock cycle forms
one instruction cycle. Although the fetching and execution of instructions takes place in consecutive
instruction cycles, the pipelining structure of the microcontroller ensures that instructions are
effectively executed in one instruction cycle. The exception to this are instructions where the
contents of the Program Counter are changed, such as subroutine calls or jumps, in which case the
instruction will take one more instruction cycle to execute.
Rev. 1.00
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HT45F3820
Ultrasonic Humidifier 8-Bit Flash MCU
fSYS
(S�stem Clock)
Phase Clock T1
Phase Clock T�
Phase Clock T�
Phase Clock T4
Program Counter
Pipelining
PC
PC+1
PC+�
Fetch Inst. (PC)
Execute Inst. (PC-1)
Fetch Inst. (PC+1)
Execute Inst. (PC)
Fetch Inst. (PC+�)
Execute Inst. (PC+1)
System Clock and Pipelining
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.
1
�OV A�[1�H]
�
CALL DELAY
�
CPL [1�H]
4
:
5
:
� DELAY: NOP
Fetch Inst. 1
Execute Inst. 1
Fetch Inst. �
Execute Inst. �
Fetch Inst. �
Flush Pipeline
Fetch Inst. �
Execute Inst. �
Fetch Inst. 7
Instruction Fetching
Program Counter
During program execution, the Program Counter is used to keep track of the address of the
next instruction to be executed. It is automatically incremented by one each time an instruction
is executed except for instructions, such as "JMP" or "CALL" that demand a jump to a nonconsecutive Program Memory address. Only the lower 8 bits, known as the Program Counter Low
Register, are directly addressable by the application program.
When executing instructions requiring jumps to non-consecutive addresses such as a jump instruction,
a subroutine call, interrupt or reset, etc., the microcontroller manages program control by loading
the required address into the Program Counter. For conditional skip instructions, once the condition
has been met, the next instruction, which has already been fetched during the present instruction
execution, is discarded and a dummy cycle takes its place while the correct instruction is obtained.
Program Counter
Program Counter High byte
PCL Register
PC9~PC8
PCL7~PCL0
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.
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HT45F3820
Ultrasonic Humidifier 8-Bit Flash MCU
Stack
This is a special part of the memory which is used to save the contents of the Program Counter
only. The stack is 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.
Program Counter
Top of Stack
Stack Level 1
Stack Level �
Stack
Pointer
Bottom of Stack
Stack Level �
Program �emor�
Stack Level 4
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. 1.00
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May 30, 2016
HT45F3820
Ultrasonic Humidifier 8-Bit Flash MCU
Flash Program Memory
The Program Memory is the location where the user code or program is stored. For this device the
Program Memory is Flash type, which means it can be programmed and re-programmed a large
number of times, allowing the user the convenience of code modification on the same device.
By using the appropriate programming tools, this Flash device offers users the flexibility to
conveniently debug and develop their applications while also offering a means of field programming
and updating.
Structure
The Program Memory has a capacity of 1K×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.
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.
000H
Reset
004H
Interrupt
Vector
0�4H
�FFH
1� bits
Program Memory Structure
Look-up Table
Any location within the Program Memory can be defined as a look-up table where programmers can
store fixed data. To use the look-up table, the table pointer must first be setup by placing the address
of the look up data to be retrieved in the table pointer register, TBLP and TBHP. These registers
define the total address of the look-up table.
After setting up the table pointer, the table data can be retrieved from the Program Memory using
the "TABRD[m]" or "TABRDL[m]" instructions, respectively. When the instruction is executed,
the lower order table byte from the Program Memory will be transferred to the user defined
Data Memory register [m] as specified in the instruction. The higher order table data byte from
the Program Memory will be transferred to the TBLH special register. Any unused bits in this
transferred higher order byte will be read as "0".
The accompanying diagram illustrates the addressing data flow of the look-up table.
Rev. 1.00
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May 30, 2016
HT45F3820
Ultrasonic Humidifier 8-Bit Flash MCU
Program �emor�
Address
Last Page or
TBHP Register
TBLP Register
Data
1� bits
Register TBLH
User Selected
Register
High B�te
Low B�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 "300H" which refers to the start
address of the last page within the 1K words Program Memory of the 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 "306H" or 6 locations after the start of the TBHP
specified page. Note that the value for the table pointer is referenced to the first address specified by
the TBHP and TBLP registers if the "TABRD [m]" instruction is being used. The high byte of the
table data which in this case is equal to zero will be transferred to the TBLH register automatically
when the "TABRD [m]" instruction is executed.
Because the TBLH register is a read-only register and cannot be restored, care should be taken
to ensure its protection if both the main routine and Interrupt Service Routine use table read
instructions. If using the table read instructions, the Interrupt Service Routines may change the
value of the TBLH and subsequently cause errors if used again by the main routine. As a rule it is
recommended that simultaneous use of the table read instructions should be avoided. However, in
situations where simultaneous use cannot be avoided, the interrupts should be disabled prior to the
execution of any main routine table-read instructions. Note that all table related instructions require
two instruction cycles to complete their operation.
Table Read Program Example
tempreg1 db ? ; temporary register #1
tempreg2 db ? ; temporary register #2
:
mov a,06h ; initialise low table pointer-note that this address is referenced
mov tblp,a ; to the last page or specific page
mov a,03h ; initialise high table pointer
mov tbhp,a
:
tabrd tempreg1 ; transfers value in table referenced by table pointer
; data at program memory address "306H" transferred to tempreg1 and TBLH
dec tblp ; reduce value of table pointer by one
tabrd tempreg2 ; transfers value in table referenced by table pointer
; data at program memory address "305H" transferred to tempreg2 and TBLH
; in this example the data "1AH" is transferred to tempreg1 and data "0FH" to
; register tempreg2, the value 00H will be transferred to the high byte
; register TBLH
:
org 300h; sets initial address of program memory
dc 00Ah, 00Bh, 00Ch, 00Dh, 00Eh, 00Fh, 01Ah, 01Bh
:
Rev. 1.00
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HT45F3820
Ultrasonic Humidifier 8-Bit Flash MCU
In Circuit Programming
The provision of Flash type Program Memory provides the user with a means of convenient and easy
upgrades and modifications to their programs on the same device. As an additional convenience,
Holtek has provided a means of programming the microcontroller in-circuit using a 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 Write Pins
MCU Programming Pins
ICPDA
PA0
Programming Serial Data/Address
Function
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 device are beyond the scope of this document and will
be supplied in supplementary literature.
During the programming process, the user must take care of the ICPDA and ICPCK pins for data
and clock programming purpose to ensure that no other outputs are connected to these two pins.
Writer Connector
Signals
�CU Programming
Pins
Writer_VDD
VDD
ICPDA
PA0
ICPCK
PA�
Writer_VSS
VSS
*
*
To other Circuit
Note: * may be resistor or capacitor. The resistance of * must be greater than 1kΩ or the capacitance
of * must be less than 1nF.
On-Chip Debug Support – OCDS
The device has an EV chip named HT45V3820 which is used to emulate the HT45F3820 device.
This EV chip device also provides an "On-Chip Debug" function to debug the real MCU device
during the development process. The EV chip and the real MCU device are almost functionally
compatible except for the "On-Chip Debug" function. Users can use the EV chip device to emulate
the real chip device behavior by connecting the OCDSDA and OCDSCK pins to the Holtek 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 EV chip for debugging, other
functions which are shared with the OCDSDA and OCDSCK pins in the device will have no effect
in the EV chip. However, the two OCDS pins which are pin-shared with the ICP programming pins
are still used as the Flash Memory programming pins for ICP. For more detailed OCDS information,
refer to the corresponding document named "Holtek e-Link for 8-bit MCU OCDS User’s Guide".
Rev. 1.00
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May 30, 2016
HT45F3820
Ultrasonic Humidifier 8-Bit Flash MCU
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
GND
VSS
Ground
RAM Data Memory
The Data Memory is a volatile area of 8-bit wide RAM internal memory and is the location where
temporary information is stored.
Structure
Divided into two sections, the first of these is an area of RAM, known as the Special Purpose Data
Memory. Here are located registers which are necessary for correct operation of the device. Many
of these registers can be read from and written to directly under program control, however, some
remain protected from user manipulation. The second area of Data Memory is known as the General
Purpose Data Memory, which is reserved for general purpose use. All locations within this area are
read and write accessible under program control.
The overall Data Memory is subdivided into two banks. The Special Purpose Data Memory registers are
accessible in all banks, with the exception of the EEC register at address 40H, which is only accessible
in Bank 1. Switching between the different Data Memory banks is achieved by setting the Bank Pointer
to the correct value. The start address of the Data Memory for the device is the address 00H.
Special Purpose Data Memory
General Purpose Data Memory
Address
Capacity
Address
Bank 0: 00H~7FH
Bank 1: 00H~7FH
64×8
Bank 0: 80H~BFH
000H
EEC
Special Purpose
Data �emor�
Bank 1
07FH
080H
General Purpose
Data �emor�
0BFH
Bank 0
Data Memory Structure
General Purpose Data Memory
All microcontroller programs require an area of read/write memory where temporary data can be
stored and retrieved for use later. It is this area of RAM memory that is known as General Purpose
Data Memory. This area of Data Memory is fully accessible by the user programing for both reading
and writing operations. By using the bit operation instructions individual bits can be set or reset under
program control giving the user a large range of flexibility for bit manipulation in the Data Memory.
Rev. 1.00
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HT45F3820
Ultrasonic Humidifier 8-Bit Flash MCU
Special Purpose Data Memory
This area of Data Memory is where registers, necessary for the correct operation of the
microcontroller, are stored. Most of the registers are both readable and writeable but some are
protected and are readable only, the details of which are located under the relevant Special Function
Register section. Note that for locations that are unused, any read instruction to these addresses will
return the value "00H".
Bank 0
Bank 0� 1
Bank 1
IAR0
�5H
Unused
01H
�P0
��H
Unused
0�H
IAR1
�7H
Unused
0�H
�P1
�8H
Unused
04H
BP
�9H
CTRL�
05H
ACC
�AH
CTRL�
0�H
PCL
�BH
00H
07H
TBLP
�CH
08H
TBLH
�DH
09H
TBHP
�EH
Unused
0AH
STATUS
�FH
0BH
S�OD
40H
0CH
LVDC
41H
0DH
INTEG
4�H
Unused
0EH
INTC0
4�H
SLEWC
0FH
INTC1
44H
SLEDC
10H
INTC�
45H
Unused
11H
Unused
4�H
PT�C0
1�H
�FI0
47H
PT�C1
1�H
�FI1
48H
PT�DL
14H
PA
49H
PT�DH
15H
PAC
4AH
PT�AL
1�H
PAPU
4BH
PT�AH
Unused
17H
PAWU
4CH
PT�RPL
18H
�FI�
4DH
PT�RPH
19H
Unused
4EH
1AH
WDTC
4FH
1BH
TBC
50H
1CH
Unused
51H
1DH
Unused
5�H
1EH
EEA
5�H
1FH
EED
54H
�0H
Unused
55H
�1H
Unused
5�H
��H
Unused
57H
��H
Unused
58H
�4H
FADJL
59H
�5H
FADJH
5AH
EEC
Unused
Unused
��H
CTRL
5BH
OCVPC0
�7H
LVRC
5CH
OCVPC1
�8H
Unused
5DH
OCVPC�
�9H
Unused
5EH
OCVPDA
�AH
Unused
5FH
OCVPOCAL
�BH
Unused
�0H
OCVPCCAL
�CH
Unused
�1H
�DH
Unused
�EH
Unused
�FH
ST�C0
�0H
ST�C1
�1H
ST�DL
��H
ST�DH
��H
ST�AL
�4H
ST�AH
Unused
7FH
: Unused� read as 00H
Special Purpose Data Memory Structure
Rev. 1.00
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HT45F3820
Ultrasonic Humidifier 8-Bit Flash MCU
Special Function Register Description
Most of the Special Function Register details will be described in the relevant functional section.
However, several registers require a separate description in this section.
Indirect Addressing Registers – IAR0, IAR1
The Indirect Addressing Registers, IAR0 and IAR1, although having their locations in normal RAM
register space, do not actually physically exist as normal registers. The method of indirect addressing
for RAM data manipulation uses these Indirect Addressing Registers and Memory Pointers, in
contrast to direct memory addressing, where the actual memory address is specified. Actions on the
IAR0 and IAR1 registers will result in no actual read or write operation to these registers but rather
to the memory location specified by their corresponding Memory Pointers, MP0 or MP1. Acting as a
pair, IAR0 and MP0 can together access data from Bank 0 while the IAR1 and MP1 register pair can
access data from any bank. As the Indirect Addressing Registers are not physically implemented,
reading the Indirect Addressing Registers indirectly will return a result of "00H" and writing to the
registers indirectly will result in no operation.
Memory Pointers – MP0, MP1
Two Memory Pointers, known as MP0 and MP1 are provided. These Memory Pointers are
physically implemented in the Data Memory and can be manipulated in the same way as normal
registers providing a convenient way with which to address and track data. When any operation to
the relevant Indirect Addressing Registers is carried out, the actual address that the microcontroller
is directed to is the address specified by the related Memory Pointer. MP0, together with Indirect
Addressing Register, IAR0, are used to access data from Bank 0, while MP1 and IAR1 are used to
access data from all banks according to BP register. Direct Addressing can only be used within Bank
0, all other Banks must be addressed indirectly using MP1 and IAR1.
The following example shows how to clear a section of four Data Memory locations already defined
as locations adres1 to adres4.
Indirect Addressing Program Example
data .section ´data´
adres1 db ?
adres2 db ?
adres3 db ?
adres4 db ?
block db ?
code .section at 0 ´code´
org 00h
start:
mov a,04h ; setup size of block
mov block,a
mov a,offset adres1 ; Accumulator loaded with first RAM address
mov mp0,a ; setup memory pointer with first RAM address
loop:
clr IAR0 ; clear the data at address defined by mp0
inc mp0; increment memory pointer
sdz block ; check if last memory location has been cleared
jmp loop
continue:
The important point to note here is that in the example shown above, no reference is made to specific
Data Memory addresses.
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Bank Pointer – BP
For this device, the Data Memory is divided into two banks, Bank0 and Bank1. Selecting the
required Data Memory area is achieved using the Bank Pointer. Bit 0 of the Bank Pointer is used to
select Data Memory Bank 0 or 1.
The Data Memory is initialised to Bank 0 after a reset, except for a WDT time-out reset in the Power
down Mode, in which case, the Data Memory bank remains unaffected. It should be noted that the
Special Purpose Data Memory is not affected by the bank selection, which means that the Special
Function Registers can be accessed from within any bank. Directly addressing the Data Memory
will always result in Bank 0 being accessed irrespective of the value of the Bank Pointer. Accessing
data from Bank1 must be implemented using Indirect Addressing.
BP Register
Bit
7
6
5
4
3
2
1
0
Name
—
—
—
—
—
—
—
DMBP0
R/W
—
—
—
—
—
—
—
R/W
POR
—
—
—
—
—
—
—
0
Bit 7 ~ 1
Unimplemented, read as "0"
Bit 0DMBP0: Select Data Memory Banks
0: Bank 0
1: Bank 1
Accumulator – ACC
The Accumulator is central to the operation of any microcontroller and is closely related with
operations carried out by the ALU. The Accumulator is the place where all intermediate results
from the ALU are stored. Without the Accumulator it would be necessary to write the result of
each calculation or logical operation such as addition, subtraction, shift, etc., to the Data Memory
resulting in higher programming and timing overheads. Data transfer operations usually involve
the temporary storage function of the Accumulator; for example, when transferring data between
one user-defined register and another, it is necessary to do this by passing the data through the
Accumulator as no direct transfer between two registers is permitted.
Program Counter Low Register – PCL
To provide additional program control functions, the low byte of the Program Counter is made
accessible to programmers by locating it within the Special Purpose area of the Data Memory. By
manipulating this register, direct jumps to other program locations are easily implemented. Loading
a value directly into this PCL register will cause a jump to the specified Program Memory location,
however, as the register is only 8-bit wide, only jumps within the current Program Memory page are
permitted. When such operations are used, note that a dummy cycle will be inserted.
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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 pointers and indicate the location
where the table data is located. Their value must be setup before any table read commands are
executed. Their value can be changed, for example using the "INC" or "DEC" instruction, allowing
for easy table data pointing and reading. TBLH is the location where the high order byte of the table
data is stored after a table read data instruction has been executed. Note that the lower order table
data byte is transferred to a user defined location.
Status Register – STATUS
This 8-bit register contains the zero flag (Z), carry flag (C), auxiliary carry flag (AC), overflow flag
(OV), power down flag (PDF), and watchdog time-out flag (TO). These arithmetic/logical operation
and system management flags are used to record the status and operation of the microcontroller.
With the exception of the TO and PDF flags, bits in the status register can be altered by instructions
like most other registers. Any data written into the status register will not change the TO or PDF flag.
In addition, operations related to the status register may give different results due to the different
instruction operations. The TO flag can be affected only by a system power-up, a WDT time-out or
by executing the "CLR WDT" or "HALT" instruction. The PDF flag is affected only by executing
the "HALT" or "CLR WDT" instruction or during a system power-up.
The Z, OV, AC and C flags generally reflect the status of the latest operations.
• C is set if an operation results in a carry during an addition operation or if a borrow does not take
place during a subtraction operation; otherwise C is cleared. C is also affected by a rotate through
carry instruction.
• AC is set if an operation results in a carry out of the low nibbles in addition, or no borrow from
the high nibble into the low nibble in subtraction; otherwise AC is cleared.
• Z is set if the result of an arithmetic or logical operation is zero; otherwise Z is cleared.
• OV is set if an operation results in a carry into the highest-order bit but not a carry out of the
highest-order bit, or vice versa; otherwise OV is cleared.
• PDF is cleared by a system power-up or executing the "CLR WDT" instruction. PDF is set by
executing the "HALT" instruction.
• TO is cleared by a system power-up or executing the "CLR WDT" or "HALT" instruction. TO is
set by a WDT time-out.
In addition, on entering an interrupt sequence or executing a subroutine call, the status register will
not be pushed onto the stack automatically. If the contents of the status registers are important and if
the subroutine can corrupt the status register, precautions must be taken to correctly save it.
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STATUS Register
Bit
7
6
5
4
3
2
1
0
Name
—
—
TO
PDF
OV
Z
AC
C
R/W
—
—
R
R
R/W
R/W
R/W
R/W
POR
—
—
0
0
x
x
x
x
"x" unknown
Bit 7~6
Unimplemented, read as "0"
Bit 5TO: Watchdog Time-out flag
0: After power up or executing the "CLR WDT" or "HALT" instruction
1: A watchdog time-out occurred.
Bit 4PDF: Power down flag
0: After power up or executing the "CLR WDT" instruction
1: By executing the "HALT" instruction
Bit 3OV: Overflow flag
0: No overflow
1: An operation results in a carry into the highest-order bit but not a carry out of the
highest-order bit or vice versa.
Bit 2Z: Zero flag
0: The result of an arithmetic or logical operation is not zero
1: The result of an arithmetic or logical operation is zero
Bit 1AC: Auxiliary flag
0: No auxiliary carry
1: An operation results in a carry out of the low nibbles in addition, or no borrow
from the high nibble into the low nibble in subtraction
Bit 0C: Carry flag
0: No carry-out
1: An operation results in a carry during an addition operation or if a borrow does
not take place during a subtraction operation
C is also affected by a rotate through carry instruction.
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EEPROM Data Memory
One of the special features in the device is its internal EEPROM Data Memory. EEPROM, which
stands for Electrically Erasable Programmable Read Only Memory, is by its nature a non-volatile
form of memory, with data retention even when its power supply is removed. By incorporating
this kind of data memory, a whole new host of application possibilities are made available to the
designer. The availability of EEPROM storage allows information such as product identification
numbers, calibration values, specific user data, system setup data or other product information to
be stored directly within the product microcontroller. The process of reading and writing data to the
EEPROM memory has been reduced to a very trivial affair.
EEPROM Data Memory Structure
The EEPROM Data Memory capacity is up to 32×8 bits. Unlike the Program Memory and RAM
Data Memory, the EEPROM Data Memory is not directly mapped and is therefore not directly
accessible in the same way as the other types of memory. Read and Write operations to the
EEPROM are carried out in single byte operations using an address and data register in Bank 0 and
a single control register in Bank 1.
EEPROM Registers
Three registers control the overall operation of the internal EEPROM Data Memory. These are the
address register, EEA, the data register, EED and a single control register, EEC. As both the EEA
and EED registers are located in Bank 0, they can be directly accessed in the same way as any other
Special Function Register. The EEC register however, being located in Bank 1, cannot be directly
addressed directly and can only be read from or written to indirectly using the MP1 Memory Pointer
and Indirect Addressing Register, IAR1. Because the EEC control register is located at address 40H
in Bank 1, the MP1 Memory Pointer must first be set to the value 40H and the Bank Pointer register,
BP, set to the value, 01H, before any operations on the EEC register are executed.
Bit
Register
Name
7
6
5
4
3
2
1
0
EEA
—
—
—
D4
D3
D2
D1
D0
EED
D7
D6
D5
D4
D3
D2
D1
D0
EEC
—
—
—
—
WREN
WR
RDEN
RD
EEPROM Control Register List
EEA Register
Rev. 1.00
Bit
7
6
5
4
3
2
1
0
Name
­—
­—
­—
D4
D3
D2
D1
D0
R/W
­—
­—
­—
R/W
R/W
R/W
R/W
R/W
POR
­—
­—
­—
0
0
0
0
0
Bit 7 ~ 5
Unimplemented, read as "0"
Bit 4 ~ 0
Data EEPROM address
Data EEPROM address bit 4 ~ 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 ~ 0
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 cannot be set to "1" at the same time in one instruction. The
WR and RD cannot 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. Note that setting the WR bit
high will not initiate a write cycle if the WREN bit has not been set. As the EEPROM write cycle is
controlled using an internal timer whose operation is asynchronous to microcontroller system clock,
a certain time will elapse before the data will have been written into the EEPROM. Detecting when
the write cycle has finished can be implemented either by polling the WR bit in the EEC register or
by using the EEPROM interrupt. When the write cycle terminates, the WR bit will be automatically
cleared to zero by the microcontroller, informing the user that the data has been written to the
EEPROM. The application program can therefore poll the WR bit to determine when the write cycle
has ended.
Write Protection
Protection against inadvertent write operation is provided in several ways. After the device is
powered on, the Write enable bit in the control register will be cleared preventing any write
operations. Also at power-on the Bank Pointer, BP, will be reset to zero, which means that Data
Memory Bank 0 will be selected. As the EEPROM control register is located in Bank 1, this adds a
further measure of protection against spurious write operations. During normal program operation,
ensuring that the Write Enable bit in the control register is cleared will safeguard against incorrect
write operations.
EEPROM Interrupt
The EEPROM write interrupt is generated when an EEPROM write cycle has ended. The EEPROM
interrupt must first be enabled by setting the DEE bit in the relevant interrupt register. However as
the EEPROM is contained within a Multi-function Interrupt, the associated multi-function interrupt
enable bit must also be set. When an EEPROM write cycle ends, the DEF request flag and its
associated multi-function interrupt request flag will both be set. If the global, EEPROM and Multifunction interrupts are enabled and the stack is not full, a jump to the associated Multi-function
Interrupt vector will take place. When the interrupt is serviced only the Multi-function interrupt flag
will be automatically reset, the EEPROM interrupt flag must be manually reset by the application
program. More details can be obtained in the Interrupt section.
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Programming Considerations
Care must be taken that data is not inadvertently written to the EEPROM. Protection can be
Periodic by ensuring that the Write Enable bit is normally cleared to zero when not writing. Also
the Bank Pointer could be normally cleared to zero as this would inhibit access to Bank 1 where
the EEPROM control register exist. Although certainly not necessary, consideration might be given
in the application program to the checking of the validity of new write data by a simple read back
process. 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 completed, 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 MP1, A
MOV A, 01H
MOV BP, A
SET IAR1.1
SET IAR1.0
BACK:
SZ IAR1.0
JMP BACK
CLR IAR1
CLR BP
MOV A, EED
MOV READ_DATA, A
; user defined address
; setup memory pointer MP1
; MP1 points to EEC register
; setup Bank Pointer
; set RDEN bit, enable read operations
; start Read Cycle-set RD bit
; check for read cycle end
; disable EEPROM 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 MP1, A
MOV A, 01H
MOV BP, A
CLR EMI
SET IAR1.3
SET IAR1.2
SET EMI
BACK:
SZ IAR1.2
JMP BACK
CLR IAR1
CLR BP
Rev. 1.00
; user defined address
; user defined data
;
;
;
;
setup memory pointer MP1
MP1 points to EEC register
setup Bank Pointer
BP points to data memory bank 1
; set WREN bit, enable write operations
; start Write Cycle-set WR bit – executed immediately after
; set WREN bit
; check for write cycle end
; disable EEPROM write
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Oscillators
Various oscillator options offer the user a wide range of functions according to their various
application requirements. The flexible features of the oscillator functions ensure that the best
optimisation can be achieved in terms of speed and power saving. Oscillator selections and operation
are selected through 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. Fully integrated internal oscillators, requiring
no external components, are provided to form a 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.
Internal High Speed RC
HIRC
12MHz (adjustable)
Internal Low Speed RC
LIRC
32kHz
Oscillator Types
System Clock Configurations
There are two methods of generating the system clock, a high speed internal RC oscillator and a low
speed internal RC oscillator. Selecting whether the low or high speed oscillator is used as the system
oscillator is implemented using the HLCLK bit and CKS2 ~ CKS0 bits in the SMOD register and as
the system clock can be dynamically selected.
The actual source clock used for the high speed and the low speed oscillators is chosen via registers.
The frequency of the slow speed or high speed system clock is also determined using the HLCLK
bit and CKS2 ~ CKS0 bits in the SMOD register. Note that two oscillator selections must be made
namely one high speed and one low speed system oscillators. It is not possible to choose a nooscillator selection for either the high or low speed oscillator.
fH/�
High Speed Oscillator
HIRC
fH/4
Frequenc�
Adjusting
Circuit
fH
fH/8
Prescaler
fH/1�
fSYS
fH/��
fH/�4
ADJ[8:0] bits
fSUB
LIRC
Low Speed Oscillator
HLCLK� CKS[�:0] bits
System Clock Configurations
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Ultrasonic Humidifier 8-Bit Flash MCU
Internal RC Oscillator – HIRC
The internal high speed RC oscillator is a fully integrated system oscillator requiring no external
components. The internal RC oscillator has a frequency of 12MHz which can be adjusted by
changing the ADJ[8:0] bits field value. 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, it requires no external pins for
its operation.
The ADJ[8:0] bit field in the FADJH and FADJL registers is used to adjust the HIRC oscillation
frequency. The HIRC oscillator is supposed to have a frequency of 12MHz with the default
ADJ[8:0] field value, 100000000B. The greater value the ADJ[8:0] field is written, the lower
frequency the HIRC oscillator has. The HIRC oscillator will have a maximum adjusted frequency
when the ADJ[8:0] field is set to 000000000B. Note that a certain time delay for the HIRC oscillator
stabilization should be allowed when the HIRC oscillation frequency is changed by configuring the
ADJ[8:0] field. The new HIRC frequency cannot be used until the updated frequency is stable.
FADJL Register
Bit
7
6
5
4
3
2
1
0
Name
ADJ7
ADJ6
ADJ5
ADJ4
ADJ3
ADJ2
ADJ1
ADJ0
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 7~0ADJ7~ADJ0: HIRC frequency adjustment control bit 7 ~ bit 0
FADJH Register
Bit
7
6
5
4
3
2
1
0
Name
­—
­—
­—
­—
­—
­—
­—
ADJ8
R/W
­—
­—
­—
­—
­—
­—
­—
R/W
POR
­—
­—
­—
­—
­—
­—
­—
1
Bit 7~1
Unimplemented, read as "0"
Bit 0ADJ8: HIRC frequency adjustment control bit 8
Internal 32kHz Oscillator – LIRC
The Internal 32kHz system oscillator is the low frequency oscillator. 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.
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Operating Modes and System Clocks
Present day applications require that their microcontrollers have high performance but often still
demand that they consume as little power as possible, conflicting requirements that are especially
true in battery powered portable applications. The fast clocks required for high performance will
by their nature increase current consumption and of course vice-versa, lower speed clocks reduce
current consumption. As Holtek has provided this device with both high and low speed clock
sources and the means to switch between them dynamically, the user can optimise the operation of
their microcontroller to achieve the best performance/power ratio.
System Clocks
The device has many different clock sources for both the CPU and peripheral function operation. By
providing the user with a wide range of clock options using 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 oscillator. The low speed system clock source can be
sourced from the LIRC oscillator. The other choice, which is a divided version of the high speed
system oscillator has a range of fH/2~fH/64.
fH/�
High Speed Oscillator
HIRC
fH/4
Frequenc�
Adjusting
Circuit
fH
fH/8
Prescaler
fSYS
fH/��
fH/�4
ADJ[8:0] bits
LIRC
fH/1�
fSUB
HLCLK� CKS[�:0] bits
Low Speed Oscillator
fSUB
To peripherals
fS
fTBC
WDT
fTB
fSYS/4
Time
Base
TBCK
Device Clock Configurations
Note: When the system clock source fSYS is switched to fSUB from fH, the high speed oscillator will
stop to conserve the power. Thus there is no fH~fH/64 for peripheral circuit to use.
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System Operating 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
fH
fSUB
NORMAL Mode
On
fH~fH/64
On
On
SLOW Mode
On
fSUB
Off
On
ILDE0 Mode
Off
Off
Off
On
IDLE1 Mode
Off
On
On/Off
On
SLEEP0 Mode (Note)
Off
Off
Off
Off
SLEEP1 Mode
Off
Off
Off
On
Note: If the Watchdog Timer configuration option is "Always enabled" which means the fSUB clock
must always be on, there is not SLEEP0 mode.
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 the high speed oscillator. This
mode operates allowing the microcontroller to operate normally with a clock source will come from
the high speed oscillator, HIRC. 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 fSUB. 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
If the WDT configuration option is "Always enabled", there is not SLEEP0 mode. If the WDT
configuration option is "controlled by WDTC register" the MCU can enter the SLEEP0 mode. The
SLEEP Mode is entered when an HALT instruction is executed and when the IDLEN bit in the
SMOD register is low. In the SLEEP0 mode the CPU will be stopped, and the fSUB and fS clocks
will be stopped too, and the Watchdog Timer function is disabled. In this mode, the LVDEN is must
cleared to zero. If the LVDEN is set high, it won’t enter the SLEEP0 Mode.
SLEEP1 Mode
The SLEEP Mode is entered when an HALT instruction is executed and when the IDLEN bit in
the SMOD register is low. In the SLEEP1 mode the CPU will be stopped. However the fSUB and fS
clocks will continue to operate if the LVDEN is "1" or the Watchdog Timer function is enabled.
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 to drive some peripheral functions.
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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 to drive some peripheral functions.
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.
Control Registers
The SMOD and CTRL registers are used to control 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
1
1
0
—
0
0
1
0
Bit 7 ~ 5
CKS2 ~ CKS0: The system clock selection when HLCLK is "0"
000: fSUB
001: fSUB
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 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: LIRC System OSC SST ready flag
0: Not ready
1: Ready
This is the low speed system oscillator SST 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 change to a high level after 1~2 cycles.
Bit 2HTO: HIRC System OSC SST ready flag
0: Not ready
1: Ready
This is the high speed system oscillator SST ready flag which indicates when the high
speed system oscillator is stable after a wake-up has occurred. 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 power on reset or a wake-up has occurred, the flag
will change to a high level after 15~16 clock cycles if the HIRC oscillator is used.
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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
Name
FSYSON
—
—
R/W
R/W
—
—
POR
0
—
—
—
1
0
—
—
—
—
LVRF
LRF
WRF
R/W
R/W
—
R/W
x
0
0
"x" unknown
Bit 7
FSYSON: fSYS Control in IDLE Mode
0: Disable
1: Enable
Bit 6 ~ 3
Unimplemented, read as "0"
Bit 2LVRF: LVR function reset flag
Described elsewhere
Bit 1LRF: LVRC control register software reset flag
Described elsewhere
Bit 0WRF: WDTC control register software reset flag
Described elsewhere
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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.
IDLE1
HALT instruction executed
CPU stop
IDLEN=1
FSYSON=1
fSYS on
fSUB on
NORMAL
fSYS=fH~fH/�4
fH on
CPU run
fSYS on
fSUB on
IDLE0
HALT instruction executed
CPU stop
IDLEN=1
FSYSON=0
fSYS off
fSUB on
SLEEP0
HALT instruction executed
fSYS off
CPU stop
IDLEN=0
fSUB off
WDT & LVD off
SLEEP1
HALT instruction executed
fSYS off
CPU stop
IDLEN=0
fSUB on
WDT or LVD on
SLOW
fSYS=fSUB
fSUB on
CPU run
fSYS on
fSUB on
fH off
Note: If the Watchdog Timer configuration option is "Always enabled" which means the fSUB clock
must always be on, there is not SLEEP0 mode.
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NORMAL Mode to SLOW Mode Switching
When running in the NORMAL Mode, which uses the high speed system oscillator, and therefore
consumes more power, the system clock can switch to run in the SLOW Mode by setting the
HLCLK bit to "0" and setting the CKS2~CKS0 bits to "000" or "001" in the SMOD register. This
will then use the low speed system oscillator which will consume less power. Users may decide to
do this for certain operations which do not require high performance and can subsequently reduce
power consumption.
The SLOW Mode is sourced from the LIRC oscillator and therefore requires this oscillator to be
stable before full mode switching occurs. This is monitored using the LTO bit in the SMOD register.
NORMAL Mode
CKS�~CKS0 = 00xB &
HLCLK = 0
SLOW Mode
WDT and LVD are all off
IDLEN=0
HALT instruction is executed
SLEEP0 Mode
WDT or LVD is on
IDLEN=0
HALT instruction is executed
SLEEP1 Mode
IDLEN=1� FSYSON=0
HALT instruction is executed
IDLE0 Mode
IDLEN=1� FSYSON=1
HALT instruction is executed
IDLE1 Mode
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SLOW Mode to NORMAL Mode Switching
In SLOW Mode the system uses 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.
SLOW Mode
CKS2~CKS0 ≠ 000B or 001B
as HLCLK = 0 or HLCLK = 1
NORMAL Mode
WDT and LVD are all off
IDLEN=0
HALT instruction is executed
SLEEP0 Mode
WDT or LVD is on
IDLEN=0
HALT instruction is executed
SLEEP1 Mode
IDLEN=1, FSYSON=0
HALT instruction is executed
IDLE0 Mode
IDLEN=1, FSYSON=1
HALT instruction is executed
IDLE1 Mode
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 are both off. When this instruction is executed under the conditions described above,
the following will occur:
• The system clock and the fSUB clock will be stopped and the application program will stop at the
"HALT" instruction.
• The Data Memory contents and registers will maintain their present condition.
• The WDT will be cleared and stopped.
• The I/O ports will maintain their present conditions.
• In the status register, the Power Down flag, PDF, will be set and the Watchdog time-out flag, TO,
will be cleared.
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Ultrasonic Humidifier 8-Bit Flash MCU
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 is on. When this instruction is executed under the conditions described above, the
following will occur:
• The system clock will be stopped and the application program will stop at the "HALT" instruction
but the WDT or LVD will remain with the clock source coming with the fSUB clock.
• The Data Memory contents and registers will maintain their present condition.
• The WDT will be cleared and resume counting as the WDT is enabled.
• The I/O ports will maintain their present conditions.
• In the status register, the Power Down flag, PDF, will be set and the Watchdog time-out flag, TO,
will be cleared.
Entering the IDLE0 Mode
There is only one way for the device to enter the IDLE0 Mode and that is to execute the "HALT"
instruction in the application program with the IDLEN bit in SMOD register equal to "1" and the
FSYSON bit in CTRL register equal to "0". When this instruction is executed under the conditions
described above, the following will occur:
• The system clock will be stopped and the application program will stop at the "HALT" instruction,
but the low frequency fSUB clock will be on.
• The Data Memory contents and registers will maintain their present condition.
• The WDT will be cleared and resume counting.
• The I/O ports will maintain their present conditions as it is enabled.
• In the status register, the Power Down flag, PDF, will be set and the Watchdog time-out flag, TO,
will be cleared.
Entering the IDLE1 Mode
There is only one way for the device to enter the IDLE1 Mode and that is to execute the "HALT"
instruction in the application program with the IDLEN bit in SMOD register equal to "1" and the
FSYSON bit in CTRL register equal to "1". When this instruction is executed under the conditions
described above, the following will occur:
• The system clock and the low frequency fSUB will be on and the application program will stop at
the "HALT" instruction.
• The Data Memory contents and registers will maintain their present condition.
• The WDT will be cleared and resume counting as it is enabled.
• The I/O ports will maintain their present conditions.
• In the status register, the Power Down flag, PDF, will be set and the Watchdog time-out flag, TO,
will be cleared.
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Ultrasonic Humidifier 8-Bit Flash MCU
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. In the IDLE1 Mode
the system oscillator is on, if the system oscillator is from the high speed system oscillator, the
additional standby current will also be perhaps in the order of several hundred micro-amps.
Wake-up
After the system enters the SLEEP or IDLE Mode, it can be woken up from one of various sources
listed as follows:
• An external falling edge on Port A
• A system interrupt
• A WDT overflow
If the device is woken up by a WDT overflow, a Watchdog Timer reset will be initiated. The 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 wakeup 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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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 fS clock which is in turn supplied
by the LIRC oscillator. The Watchdog Timer source clock is then subdivided by a ratio of 28 to
218 to give longer timeouts, the actual value being chosen using the WS2~WS0 bits in the WDTC
register. The LIRC internal oscillator has an approximate period of 32kHz at a supply voltage of 5V.
However, it should be noted that this specified internal clock period can vary with VDD, temperature
and process variations.
Watchdog Timer Control Register
A single register, WDTC, controls the required timeout period as well as the enable/disable
operation. This register together with the configuration option control the overall operation of the
Watchdog Timer.
WDTC Register
Bit
7
6
5
4
3
2
1
0
Name
WE4
WE3
WE2
WE1
WE0
WS2
WS1
WS0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
1
0
1
0
0
1
1
Bit 7~3WE4~WE0: WDT function enable/disable control
If the WDT configuration option is "Always enabled":
10101 or 01010: Enable
Others: Reset MCU
If the WDT configuration option is "Controlled by WDTC register":
10101: Disable
01010: Enable
Others: Reset MCU
When these bits are changed by the environmental noise or software setting to reset
the microcontroller, the reset operation will be activated after a delay time, tSRESET and
the WRF bit in the CTRL register will be set high.
Bit 2~0WS2~WS0: WDT time-out period selection
000: 28/fS
001: 210/fS
010: 212/fS
011: 214/fS
100: 215/fS
101: 216/fS
110: 217/fS
111: 218/fS
These three bits determine the division ratio of the Watchdog Timer source clock,
which in turn determines the timeout period.
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CTRL Register
Bit
7
6
5
4
3
2
1
0
Name
FSYSON
—
—
—
—
LVRF
LRF
WRF
R/W
R/W
—
—
—
—
R/W
R/W
R/W
POR
0
—
—
—
—
x
0
0
"x" unknown
Bit 7FSYSON: fSYS Control in IDLE Mode
Described elsewhere.
Bit 6~3
Unimplemented, read as "0"
Bit 2LVRF: LVR function reset flag
Described elsewhere.
Bit 1LRF: LVRC Control register software reset flag
Described elsewhere.
Bit 0WRF: WDTC Control register software reset flag
0: Not occur
1: Occurred
This bit is set high by the WDT Control register software reset and cleared by the
application program. Note that this bit can only be cleared to zero by the application
program.
Watchdog Timer Operation
The Watchdog Timer operates by providing a device reset when its timer overflows. This means
that in the application program and during normal operation the user has to strategically clear the
Watchdog Timer before it overflows to prevent the Watchdog Timer from executing a reset. This is
done using the clear watchdog instructions. If the program malfunctions for whatever reason, jumps
to an unknown location, or enters an endless loop, these clear instructions will not be executed in the
correct manner, in which case the Watchdog Timer will overflow and reset the device. With regard
to the Watchdog Timer enable/disable function, there are also five bits, WE4~WE0, in the WDTC
register to offer additional enable/disable and reset control of the Watchdog Timer. If the WDT
configuration option is that the WDT function is always enabled, the WE4~WE0 bits still have
effects on the WDT function. When the WE4~WE0 bits value is equal to 01010B or 10101B, the
WDT function is enabled. However, if the WE4~WE0 bits are changed to any other values except
01010B and 10101B, which is caused by the environmental noise or software setting, it will reset
the microcontroller after 2~3 fSUB clock cycles. If the WDT configuration option is that the WDT
function is controlled by the WDTC register, the WE4~WE0 values can determine which mode the
WDT operates in. The WDT function will be disabled when the WE4~WE0 bits are set to a value of
10101B. The WDT function will be enabled if the WE4~WE0 bits value is equal to 01010B. If the
WE4~WE0 bits are set to any other values except 01010B and 10101B by the environmental noise
or software setting, it will reset the device after 2~3 fSUB clock cycles. After power on these bits will
have the value of 01010B.
WDT Configuration Option
Always Enabled
WE4 ~ WE0 Bits
WDT Function
01010B or 10101B
Enable
Any other values
Reset MCU
10101B
Disable
01010B
Enable
Any other values
Reset MCU
Controlled by WDTC Register
Watchdog Timer Enable/Disable Control
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Under normal program operation, a Watchdog Timer time-out will initialise a device reset and set
the status bit TO. However, if the system is in the SLEEP or IDLE Mode, when a Watchdog Timer
time-out occurs, the TO bit in the status register will be set and only the Program Counter and Stack
Pointer will be reset. Three methods can be adopted to clear the contents of the Watchdog Timer.
The first is a WDT reset, which means a certain value except 01010B and 10101B written into the
WE4~WE0 bit filed, the second is using the Watchdog Timer software clear instructions and the
third is via a HALT instruction.
There is only one method of using software instruction to clear the Watchdog Timer. That is to use
the single "CLR WDT" instruction to clear the WDT.
The maximum time out period is when the 218 division ratio is selected. As an example, with a
32kHz LIRC oscillator as its source clock, this will give a maximum watchdog period of around 8
second for the 218 division ratio, and a minimum timeout of 7.8ms for the 28 division ration.
WDTC Register
WE4~WE0 bits
Reset �CU
CLR
“CLR WDT” Instruction
“HALT” Instruction
LIRC
fS
8-stage Divider
fS/�8
WS�~WS0
WDT Prescaler
WDT Time-out
8-to-1 �UX
Watchdog Timer
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Reset and Initialisation
A reset function is a fundamental part of any microcontroller ensuring that the device can be set
to some predetermined condition irrespective of outside parameters. The most important reset
condition is after power is first applied to the microcontroller. In this case, internal circuitry will
ensure that the microcontroller, after a short delay, will be in a well defined state and ready to
execute the first program instruction. After this power-on reset, certain important internal registers
will be set to defined states before the program commences. One of these registers is the Program
Counter, which will be reset to zero forcing the microcontroller to begin program execution from the
lowest Program Memory address.
Another type of reset is when the Watchdog Timer overflows and resets the microcontroller. All
types of reset operations result in different register conditions being setup. Another reset exists in the
form of a Low Voltage Reset, LVR, where a full reset is implemented in situations where the power
supply voltage falls below a certain threshold.
Reset Functions
There are several ways in which a microcontroller reset can occur, through events occurring
internally:
Power-on Reset
The most fundamental and unavoidable reset is the one that occurs after power is first applied to
the microcontroller. As well as ensuring that the Program Memory begins execution from the first
memory address, a power-on reset also ensures that certain other registers are preset to known
conditions. All the I/O port and port control registers will power up in a high condition ensuring that
all pins will be first set to inputs.
VDD
Power-on Reset
tRSTD
SST Time-out
Power-On Reset Timing Chart
Low Voltage Reset – LVR
The microcontroller contains a low voltage reset circuit in order to monitor the supply voltage of the
device. The LVR function is always enabled with a specific LVR voltage, VLVR. If the supply voltage
of the device drops to within a range of 0.9V~VLVR such as might occur when changing the battery,
the LVR will automatically reset the device internally and the LVRF bit in the CTRL register will
also be set high. For a valid LVR signal, a low voltage, i.e., a voltage in the range between 0.9V~VLVR
must exist for greater than the value tLVR specified in the LVD&LVR characteristics table. If the low
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 is defined by the LVS7~LVS0 bits in the LVRC register. If the LVS7~LVS0 bits
are changed to any other value except some certain values defined in the LVRC register by the
environmental noise, the LVR will reset the device after 2~3 LIRC clock cycles. When this happens,
the LRF bit in the CTRL register will be set high. After power on the register will have the value of
01010101B. Note that the LVR function will be automatically disabled when the device enters the
power down mode.
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Ultrasonic Humidifier 8-Bit Flash MCU
LVR
tRSTD + tSST
Internal Reset
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 ~ 0
LVS7 ~ LVS0: LVR Voltage Select control
01010101: 2.1V
00110011: 2.55V
10011001: 3.15V
10101010: 3.8V
Other values: MCU reset – register is reset to POR value
When an actual low voltage condition occurs, an MCU reset will be generated. The
reset operation will be activated after the low voltage condition keeps more than a
tLVR time. In this situation this register contents will remain the same after such a reset
occurs.
Any register value, other than the defined values above, will also result in the
generation of an MCU reset. The reset operation will be activated after a delay time,
tSRESET. However in this situation this register contents will be reset to the POR value.
• CTRL Register
Bit
7
6
5
4
3
2
1
0
Name
FSYSON
—
—
—
—
LVRF
LRF
WRF
R/W
R/W
—
—
—
—
R/W
R/W
R/W
POR
0
—
—
—
—
x
0
0
"x" unknown
Bit 7
FSYSON: fSYS Control in IDLE Mode
Described elsewhere
Bit 6 ~ 3
Unimplemented, read as "0"
Bit 2LVRF: LVR function reset flag
0: Not occurred
1: Occurred
This bit is set high when a specific low voltage reset situation condition occurs. This
bit can only be cleared to zero by application program.
Bit 1LRF: LVRC control register software reset flag
0: Not occurred
1: Occurred
This bit is set high when the LVRC register contains any undefined LVR voltage
register value. This in effect acts like a software reset function. This bit can only be
cleared to zero by application program.
Bit 0WRF: WDTC control register software reset flag
Described elsewhere
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Watchdog Time-out Reset during Normal Operation
The Watchdog time-out Reset during normal operation is the same as a LVR reset except that the
Watchdog time-out flag TO will be set high.
WDT Time-out
tRSTD + tSST
Internal Reset
WDT Time-out Reset during Normal Operation Timing Chart
Watchdog Time-out Reset during SLEEP or IDLE Mode
The Watchdog time-out Reset during SLEEP or IDLE Mode is a little different from other kinds
of reset. Most of the conditions remain unchanged except that the Program Counter and the Stack
Pointer will be cleared to zero and the TO flag will be set high. Refer to the A.C. Characteristics for
tSST details.
WDT Time-out
tSST
Internal Reset
WDT Time-out Reset during SLEEP or IDLE Timing Chart
Reset Initial Conditions
The different types of reset described affect the reset flags in different ways. These flags, known
as PDF and TO are located in the status register and are controlled by various microcontroller
operations, such as the SLEEP or IDLE Mode function or Watchdog Timer. The reset flags are
shown in the table:
TO
PDF
0
0
Power-on reset
RESET Conditions
u
u
LVR reset during NORMAL or SLOW Mode operation
1
u
WDT time-out reset during NORMAL or SLOW Mode operation
1
1
WDT time-out reset during IDLE or SLEEP Mode operation
Note: "u" stands for unchanged
The following table indicates the way in which the various components of the microcontroller are
affected after a power-on reset occurs.
Item
Rev. 1.00
Condition After RESET
Program Counter
Reset to zero
Interrupts
All interrupts will be disabled
WDT
Clear after reset, WDT begins counting
Timer Modules
Timer Modules will be turned off
Input/Output Ports
I/O ports will be setup as inputs
Stack Pointer
Stack Pointer will point to the top of the stack
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The different kinds of resets all affect the internal registers of the microcontroller in different ways.
To ensure reliable continuation of normal program execution after a reset occurs, it is important to
know what condition the microcontroller is in after a particular reset occurs. The following table
describes how each type of reset affects each of the microcontroller internal registers.
Reset
(Power On)
WDT Time-out
(Normal Operation)
WDT Time-out
(SLEEP/IDLE)
MP0
xxxx xxxx
uuuu uuuu
uuuu uuuu
MP1
xxxx xxxx
uuuu uuuu
uuuu uuuu
BP
---- ---0
---- ---0
---- ---u
ACC
xxxx xxxx
uuuu uuuu
uuuu uuuu
Register
Rev. 1.00
PCL
0000 0000
0000 0000
0000 0000
TBLP
xxxx xxxx
uuuu uuuu
uuuu uuuu
TBLH
xxxx xxxx
uuuu uuuu
uuuu uuuu
TBHP
---- -xxx
---- -uuu
---- -uuu
STATUS
--00 xxxx
--1u uuuu
- - 11 u u u u
SMOD
11 0 - 0 0 1 0
11 0 - 0 0 1 0
uuu- uuuu
LVDC
--00 -000
--00 -000
--uu -uuu
INTEG
---- 0000
---- 0000
---- uuuu
INTC0
--00 -000
--00 -000
--uu -uuu
INTC1
0000 0000
0000 0000
uuuu uuuu
INTC2
--00 --00
--00 --00
--uu --uu
MFI0
--00 --00
--00 --00
--uu --uu
MFI1
--00 --00
--00 --00
--uu --uu
PA
1111 1111
1111 1111
uuuu uuuu
PAC
1111 1111
1111 1111
uuuu uuuu
PAPU
0000 0000
0000 0000
uuuu uuuu
PAWU
0000 0000
0000 0000
uuuu uuuu
MFI2
--00 --00
--00 --00
--uu --uu
WDTC
0 1 0 1 0 0 11
0 1 0 1 0 0 11
uuuu uuuu
TBC
0 0 11 - 111
0 0 11 - 111
uuuu -uuu
EEA
--00 0000
--00 0000
--uu uuuu
EED
0000 0000
0000 0000
uuuu uuuu
EEC
---- 0000
---- 0000
---- uuuu
FADJL
0000 0000
0000 0000
uuuu uuuu
FADJH
---- ---1
---- ---1
---- ---u
CTRL
0--- -x00
0--- -000
u--- -uuu
LVRC
0101 0101
0101 0101
uuuu uuuu
STMC0
0000 0000
0000 0000
uuuu uuuu
STMC1
0000 0000
0000 0000
uuuu uuuu
STMDL
0000 0000
0000 0000
uuuu uuuu
STMDH
---- --00
---- --00
---- --uu
STMAL
0000 0000
0000 0000
uuuu uuuu
STMAH
---- --00
---- --00
---- --uu
CTRL2
---- --00
---- --00
---- --uu
CTRL3
-000 0000
-000 0000
-uuu uuuu
SLEWC
---- --00
---- --00
---- --uu
SLEDC
---- 0000
---- 0000
---- uuuu
PTMC0
0000 0---
0000 0---
uuuu u---
PTMC1
0000 0000
0000 0000
uuuu uuuu
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Reset
(Power On)
WDT Time-out
(Normal Operation)
WDT Time-out
(SLEEP/IDLE)
PTMDL
0000 0000
0000 0000
uuuu uuuu
PTMDH
---- --00
---- --00
---- --uu
PTMAL
0000 0000
0000 0000
uuuu uuuu
PTMAH
---- --00
---- --00
---- --uu
PTMRPL
0000 0000
0000 0000
uuuu uuuu
PTMRPH
---- --00
---- --00
---- --uu
OCVPC0
11 0 0 1 0 0 0
11 0 0 1 0 0 0
uuuu uuuu
OCVPC1
0000 --00
0000 --00
uuuu --uu
OCVPC2
-000 0000
-000 0000
-uuu uuuu
OCVPDA
0000 0000
0000 0000
uuuu uuuu
Register
OCVPOCAL
0010 0000
0010 0000
uuuu uuuu
OCVPCCAL
0001 0000
0001 0000
uuuu uuuu
Note: "-" stands for unimplemented
"u" stands for unchanged
"x" stands for unknown
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 name PA. 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.
Bit
Register
Name
7
6
5
4
3
2
1
0
PA
PA7
PA6
PA5
PA4
PA3
PA2
PA1
PA0
PAC
PAC7
PAC6
PAC5
PAC4
PAC3
PAC2
PAC1
PAC0
PAPU
PAPU7
PAPU6
PAPU5
PAPU4
PAPU3
PAPU2
PAPU1
PAPU0
PAWU
PAWU7
PAWU6
PAWU5
PAWU4
PAWU3
PAWU2
PAWU1
PAWU0
I/O Logic Function Registers List
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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, and are implemented using weak PMOS
transistors.
Note that only when the I/O ports are configured as digital input or NMOS output, the internal pullhigh functions can be enabled using the PAPU registers. In other conditions, internal pull-high
functions are disabled.
PAPU Register
Bit
7
6
5
4
3
2
1
0
Name
PAPU7
PAPU6
PAPU5
PAPU4
PAPU3
PAPU2
PAPU1
PAPU0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
0
0
0
0
0
0
0
Bit 7 ~ 0PAPU7~PAPU0: Port A Pin Pull-high Control
0: Disable
1: Enable
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.
Note that only when the Port A pins are configured as general purpose I/Os and the device is in the
HALT status, the Port A wake-up functions can be enabled using the relevant bits in the PAWU
register. In other conditions, the wake-up functions are disabled.
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 Pin Wake-up Control
0: Disable
1: Enable
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I/O Port Control Registers
Each I/O port has its own control register known as PAC, to control the input/output configuration.
With this control register, each CMOS output or input can be reconfigured dynamically under
software control. Each pin of the I/O ports is directly mapped to a bit in its associated port control
register. For the I/O pin to function as an input, the corresponding bit of the control register must
be written as a "1". This will then allow the logic state of the input pin to be directly read by
instructions. When the corresponding bit of the control register is written as a "0", the I/O pin will
be setup as a CMOS output. If the pin is currently setup as an output, instructions can still be used
to read the output register. However, it should be noted that the program will in fact only read the
status of the output data latch and not the actual logic status of the output pin.
PAC Register
Bit
7
6
5
4
3
2
1
0
Name
PAC7
PAC6
PAC5
PAC4
PAC3
PAC2
PAC1
PAC0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
1
1
1
1
1
1
1
1
Bit 7 ~ 0PAC7~PAC0: Port A Pin Input/Output Type Selection
0: Output
1: Input
I/O Port Source Current Control
The device supports different source current driving capability for PA port. With the corresponding
selection register, SLEDC, each I/O port can support four levels of the source current driving
capability. Users should refer to the D.C. characteristics section to select the desired source current
for different applications.
SLEDC Register
Bit
7
6
5
4
3
2
1
0
Name
—
—
—
—
SLEDC3
SLEDC2
SLEDC1
SLEDC0
R/W
—
—
—
—
R/W
R/W
R/W
R/W
POR
—
—
—
—
0
0
0
0
Bit 7~4
Unimplemented, read as "0"
Bit 3~2SLEDC3~SLEDC2: PA7~PA4 Source Current Selection
00: Source current=Level 0 (min.)
01: Source current=Level 1
10: Source current=Level 2
11: Source current=Level 3 (max.)
Bit 1~0SLEDC1~SLEDC0: PA3, PA2, PA0 Source Current Selection
00: Source current=Level 0 (min.)
01: Source current=Level 1
10: Source current=Level 2
11: Source current=Level 3 (max.)
Note: Users should refer to the D.C. Characteristics section to obtain the exact value for different
applications.
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I/O Port Output Slew Rate Control
The device supports different output slew rate driving capability for PA1 port. With the
corresponding selection register, SLEWC, PA1 port can support four levels of the output slew rate
driving capability. Users should refer to the D.C. characteristics section to select the desired output
slew rate for different applications.
SLEWC Register
Bit
7
6
5
4
3
2
Name
—
—
—
—
—
—
R/W
—
—
—
—
—
—
R/W
R/W
POR
—
—
—
—
—
—
0
0
Bit 7~2
1
0
SLEWC1 SLEWC0
Unimplemented, read as "0"
Bit 1~0SLEWC1~SLEWC0: PA1 Output Slew Rate Selection
00: Slew Rate=Level 0 (min.)
01: Slew Rate=Level 1
10: Slew Rate=Level 2
11: Slew Rate=Level 3 (max.)
Note: Users should refer to the D.C. Characteristics section to obtain the exact value for different
applications.
Pin-shared Function
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
desired function of the multi-function I/O pins is selected by a series of registers via the application
program control.
Pin-shared Function Selection Registers
The most important point to note is to make sure that the desired pin-shared function is properly
selected and also deselected. To select the desired pin-shared function, the pin-shared function
should first be correctly selected using the corresponding pin-shared control register. After that the
corresponding peripheral functional setting should be configured and then the peripheral function
can be enabled. To correctly deselect the pin-shared function, the peripheral function should first be
disabled and then the corresponding pin-shared function control register can be modified to select
other pin-shared functions.
When the pin-shared input function is selected to be used, the corresponding input and output
functions selection should be properly managed. For example, if the OCVP is used, the
corresponding output pin-shared function should be configured as the OCVPAI0/ OCVPCI function
by configuring the CTRL3 register and the OCVPAI0 signal intput should be properly selected using
the CTRL2 register. However, if the external interrupt function is selected to be used, the relevant
output pin-shared function should be selected as an I/O function and the interrupt input signal should
be selected.
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• CTRL3 Register
Bit
7
6
5
4
3
2
1
0
Name
—
IOCN6
IOCN5
IOCN4
IOCN3
IOCN2
IOCN1
IOCN0
R/W
—
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
—
0
0
0
0
0
0
0
Bit 7
Unimplemented, read as "0"
Bit 6
IOCN6: PA7 pin-shared function selection
0: PA7
1: OCVPAI0
Bit 5
IOCN5: PA6 pin-shared function selection
0: PA6
1: OCVPAI0
Bit 4
IOCN4: PA5 pin-shared function selection
0: INT1/STCK/PA5
1: OCVPCI
The INT1 or STCK pin function is furtherly selected using the corresponding function
selection bits in the interrupt control register or STM control register.
Bit 3~2
IOCN3 ~ IOCN2: PA4 pin-shared function selection
00: PA4
01: STP
10: OCVPAI0
11: VREF
Bit 1
IOCN1: PA3 pin-shared function selection
0: INT0/PTCK/PA3
1: OCVPAI0
The INT0 or PTCK pin function is furtherly selected using the corresponding function
selection bits in the interrupt control register or PTM control register.
Bit 0IOCN0: PA1 pin-shared function selection
0: PA1
1: PTP
• CTRL2 Register
Rev. 1.00
Bit
7
6
5
4
3
2
Name
—
—
—
—
—
—
1
0
OCVPS1 OCVPS0
R/W
—
—
—
—
—
—
R/W
R/W
POR
—
—
—
—
—
—
0
0
Bit 7~2
Unimplemented, read as "0"
Bit 1~0
OCVPS1 ~ OCVPS0: OCVPAI0 Input Source Pin Selection
00: OCVPAI0 on PA4
01: OCVPAI0 on PA3
10: OCVPAI0 on PA6
11: OCVPAI0 on PA7
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I/O Pin Structures
The accompanying diagram illustrates the internal structures of the logic I/O fuction. As the exact
logical construction of the I/O pin will differ from this diagram, it is supplied as a guide only to
assist with the functional understanding of the logic function I/O pins. The wide range of pin-shared
structures does not permit all types to be shown.
VDD
Control Bit
Data Bus
Write Control Register
Chip Reset
Read Control Register
D
Weak
Pull-up
CK Q
S
I/O pin
Data Bit
D
Write Data Register
Q
Pull-high
Register
Select
Q
CK Q
S
Read Data Register
S�stem Wake-up
�
U
X
wake-up Select
PA onl�
Logic Function Input/Output Structure
Programming Considerations
Within the user program, one of the first things to consider is port initialisation. After a reset, all of
the I/O data and port control registers will be set high. This means that all I/O pins will default to
an input state, the level of which depends on the other connected circuitry and whether pull-high
selections have been chosen. If the port control registers, PAC, is then programmed to setup some
pins as outputs, these output pins will have an initial high output value unless the associated port
data register, PA, is 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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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 the 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, Standard and Periodic TM sections.
Introduction
The device contains a 10-bit Standard TM named STM and a 10-bit Periodic TM, named PTM.
Although similar in nature, the different TM types vary in their feature complexity. The common
features to the Standard and Periodic TMs will be described in this section and the detailed operation
will be described in corresponding sections. The main features and differences between the two
types of TM are summarised in the accompanying table.
Function
STM
PTM
Timer/Counter
√
√
I/P Capture
√
√
Compare Match Output
√
√
PWM Channels
1
1
Single Pulse Output
PWM Alignment
PWM Adjustment Period & Duty
1
1
Edge
Edge
Duty or Period
Duty or Period
TM Function Summary
STM
PTM
10-bit STM
10-bit PTM
TM Name/Type Reference
TM Operation
The two different types of TMs offer a diverse range of functions, from simple timing operations
to PWM signal generation. The key to understanding how the TM operates is to see it in terms of
a free running counter whose value is then compared with the value of pre-programmed internal
comparators. When the free running counter has the same value as the pre-programmed comparator,
known as a compare match situation, a TM interrupt signal will be generated which can clear the
counter and perhaps also change the condition of the TM output pin. The internal TM counter is
driven by a user selectable clock source, which can be an internal clock or an external pin.
TM Clock Source
The clock source which drives the main counter in the TM can originate from various sources. The
selection of the required clock source is implemented using the xTCK2~xTCK0 bits in the xTM
control registers, where "x" can stand for S or P Type TM. The clock source can be a ratio of either
the system clock fSYS or the internal high clock fH, the fSUB clock source or the external xTCK pin.
The xTCK pin clock source is used to allow an external signal to drive the TM as an external clock
source or for event counting.
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TM Interrupts
The Standard and Periodic type TMs each has two internal interrupts, 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 xTCK. The TM
input pin, xTCK, is essentially a clock source for the TM and is selected using the xTCK2~xTCK0
bits in the xTMC0 register. This external TM input pin allows an external clock source to drive the
internal TM. The TM input pin can be chosen to have either a rising or falling active edge.
For the STM and PTM, there is another input pin xTP, which also can be the STM or PTM output
pin. The STM or PTM pin is the capture input pin whose active edge can be a rising edge, a
falling edge or both rising and falling edges. The active edge transition type is selected using the
STIO1~STIO0 bits in the STMC1 register or PTIO1~PTIO0 bits in the PTMC1 register. For the
PTM, there is another capture input, PTCK, for PTM capture input mode, which can be used as the
external trigger input source.
The TMs each have one output pins, named xTP. The TM output pin can be selected using the
corresponding pin-shared function selection bits described in the Pin-shared Function section. 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 xTPn output
pin is also the pin where the TM generates the PWM output waveform.
As the TM input or output pins are pin-shared with other functions, the TM external pin function
must first be setup using registers. A single bit in the Pin-shared Function Selection Registers
determines if its associated pin is to be used as an external TM pin or if it is to have another
function.
STM
PTM
Input
Output
Input
Output
STCK/STP
STP
PTCK/PTP
PTP
TM External Pins
TM Input/Output Pin Control Register
Selecting to have a TM input/output or whether to retain its other shared function is implemented
using one register, with a single bit in the register corresponding to a TM input/output pin. Setting
the bit high will setup the corresponding pin as a TM input/output, if reset to zero the pin will retain
its original other function.
TCK input
STCK
ST�
CCR capture input
STP
CCR output
STM Function Pin Control Block Diagram
Rev. 1.00
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TCK input
CCR capture input
PTCK
PT�
CCR capture input
CCR output
PTP
PTM Function Pin Control Block Diagram
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 these registers 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 xTMAL
and PTMRPL, in the following access procedures. Accessing the CCRA or CCRP low byte register
without following these access procedures will result in unpredictable values.
xT� Counter Register (Read onl�)
xT�DL
xT�DH
8-bit
Buffer
xT�AL
xT�AH
xT� CCRA Register
(Read/Write)
PT�RPL
PT�RPH
PT� CCRP Register (Read/Write)
Data Bus
The following steps show the read and write procedures:
• Writing Data to CCRA or CCRP
♦♦
Step 1. Write data to Low Byte xTMAL or PTMRPL
––note that here data is only written to the 8-bit buffer.
♦♦
Step 2. Write data to High Byte xTMAH or PTMRPH
––here data is written directly to the high byte registers and simultaneously data is latched
from the 8-bit buffer to the Low Byte registers.
• Reading Data from the Counter Registers and CCRA or CCRP
Rev. 1.00
♦♦
Step 1. Read data from the High Byte xTMDH, xTMAH or PTMRPH
––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 xTMDL, xTMAL or PTMRPL
––this step reads data from the 8-bit buffer.
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Standard Type TM – STM
The Standard Type TM contains five operating modes, which are Compare Match Output, Timer/
Event Counter, Capture Input, Single Pulse Output and PWM Output modes. The Standard TM can
be controlled with one external input pin and can drive one external output pin.
CCRP
fSYS/4
fSYS
fH/1�
fH/�4
fSUB
fSUB
STCK
000
001
010
011
100
101
110
111
�-bit Comparator P
Comparator P �atch
ST�PF Interrupt
STOC
b7~b9
10-bit Count-up Counter
STON
STPAU
STCK�~STCK0
STCCLR
b0~b9
10-bit Comparator A
Output
Control
Polarit�
Control
Pin
Control
ST�1� ST�0
STIO1� STIO0
STPOL
IOCN�~IOCN�
Counter Clear 0
1
Comparator A �atch
STP
ST�AF Interrupt
STIO1� STIO0
Edge
Detector
CCRA
Standard Type TM Block Diagram
Standard TM Operation
At its core is a 10-bit count-up counter which is driven by a user selectable internal 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 3-bit
wide whose value is compared with the highest 3 bits in the counter while the CCRA is the 10 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 STON 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 STM interrupt signal will also usually be generated. The Standard
Type TM can operate in a number of different operational modes, can be driven by different clock
sources and can also control an output pin. All operating setup conditions are selected using relevant
internal registers.
Standard Type TM Register Description
Overall operation of the Standard TM is controlled using series of registers. A read only register
pair exists to store the internal counter 10-bit value, while a read/write register pair exists to store
the internal 10-bit CCRA value. The remaining two registers are control registers which setup the
different operating and control modes as well as three CCRP bits.
Bit
Register
Name
7
6
5
4
3
2
1
0
STMC0
STPAU
STCK2
STCK1
STCK0
STON
STRP2
STRP1
STRP0
STMC1
STM1
STM0
STIO1
STIO0
STOC
STPOL
STDPX
STCCLR
STMDL
D7
D6
D5
D4
D3
D2
D1
D0
STMDH
—
—
—
—
—
—
D9
D8
STMAL
D7
D6
D5
D4
D3
D2
D1
D0
STMAH
—
—
—
—
—
—
D9
D8
10-bit Standard TM Register List
Rev. 1.00
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STMC0 Register
Bit
7
6
5
4
3
2
1
0
Name
STPAU
STCK2
STCK1
STCK0
STON
STRP2
STRP1
STRP0
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 7STPAU: STM 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 STM 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 6~4STCK2~STCK0: Select STM Counter clock
000: fSYS/4
001: fSYS
010: fH/16
011: fH/64
100: fSUB
101: fSUB
110: STCK rising edge clock
111: STCK falling edge clock
These three bits are used to select the clock source for the STM. The external pin clock
source can be chosen to be active on the rising or falling edge. The clock source fSYS is
the system clock, while fH and fSUB are other internal clocks, the details of which can
be found in the oscillator section.
Bit 3STON: STM Counter On/Off Control
0: Off
1: On
This bit controls the overall on/off function of the STM. Setting the bit high enables
the counter to run, clearing the bit disables the STM. Clearing this bit to zero will
stop the counter from counting and turn off the STM 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 STM is in
the Compare Match Output Mode or the PWM output Mode or Single Pulse Output
Mode then the STM output pin will be reset to its initial condition, as specified by the
STOC bit, when the STON bit changes from low to high.
Bit 2~0
Rev. 1.00
STRP2 ~ STRP0: STM CCRP 3-bit register, compared with the STM Counter bit 9~bit 7
Comparator P Match Period
000: 1024 STM clocks
001: 128 STM clocks
010: 256 STM clocks
011: 384 STM clocks
100: 512 STM clocks
101: 640 STM clocks
110: 768 STM clocks
111: 896 STM 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 STCCLR bit is set to
zero. Setting the STCCLR bit to zero ensures that a compare match with the CCRP
values will reset the internal counter. As the CCRP bits are only compared with the
highest three counter bits, the compare values exist in 128 clock cycle multiples.
Clearing all three bits to zero is in effect allowing the counter to overflow at its
maximum value.
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STMC1 Register
Rev. 1.00
Bit
7
6
5
4
3
2
1
0
Name
STM1
STM0
STIO1
STIO0
STOC
STPOL
STDPX
STCCLR
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
STM1 ~ STM0: Select STM Operating Mode
00: Compare Match Output Mode
01: Capture Input Mode
10: PWM Output Mode or Single Pulse Output Mode
11: Timer/Counter Mode
These bits setup the required operating mode for the STM. To ensure reliable operation
the STM should be switched off before any changes are made to the STM1 and STM0
bits. In the Timer/Counter Mode, the STM output pin state is undefined.
Bit 5~4
STIO1 ~ STIO0: Select STM function
Compare Match Output Mode
00: No change
01: Output low
10: Output high
11: Toggle output
PWM output 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 STP
01: Input capture at falling edge of STP
10: Input capture at falling/rising edge of STP
11: Input capture disabled
Timer/counter Mode
Unused
These two bits are used to determine how the STM output pin changes state when a
certain condition is reached. The function that these bits select depends upon in which
mode the STM is running.
In the Compare Match Output Mode, the STIO1~STIO0 bits determine how the STM
output pin changes state when a compare match occurs from the Comparator A. The
STM 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 STIO1~STIO0
bits are both zero, then no change will take place on the output. The initial value of
the STM output pin should be setup using the STOC bit. Note that the output level
requested by the STIO1~STIO0 bits must be different from the initial value setup
using the STOC bit otherwise no change will occur on the STM output pin when a
compare match occurs. After the STM output pin changes state, it can be reset to its
initial level by changing the level of the STON bit from low to high.
In the PWM Output Mode, the STIO1 and STIO0 bits determine how the STM 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 STIO1 and STIO0 bits only after the STM has been switched off. Unpredictable
PWM outputs will occur if the STIO1 and STIO0 bits are changed when the STM is
running.
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Bit 3STOC: STM Output control bit
Compare Match Output Mode
0: Initial low
1: Initial high
PWM output Mode/ Single Pulse Output Mode
0: Active low
1: Active high
This is the output control bit for the STM output pin. Its operation depends upon
whether STM is being used in the Compare Match Output Mode or in the PWM
output Mode/ Single Pulse Output Mode. It has no effect if the STM is in the Timer/
Counter Mode. In the Compare Match Output Mode it determines the logic level
of the STM output pin before a compare match occurs. In the PWM output Mode it
determines if the PWM signal is active high or active low. In the Single Pulse Output
Mode it determines the logic level of the STM output pin when the STON bit changes
from low to high.
Bit 2STPOL: STM Output polarity Control
0: Non-invert
1: Invert
This bit controls the polarity of the STM output pin. When the bit is set high the STM
output pin will be inverted and not inverted when the bit is zero. It has no effect if the
STM is in the Timer/Counter Mode.
Bit 1STDPX: STM 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 0STCCLR: Select STM Counter clear condition
0: STM Comparator P match
1: STM Comparator A match
This bit is used to select the method which clears the counter. Remember that the
Standard TM contains two comparators, Comparator A and Comparator P, either of
which can be selected to clear the internal counter. With the STCCLR 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 STCCLR bit is not
used in the PWM output mode, Single Pulse or Input Capture Mode.
STMDL Register
Bit
7
6
5
4
3
2
1
0
Name
D7
D6
D5
D4
D3
D2
D1
D0
R/W
R
R
R
R
R
R
R
R
POR
0
0
0
0
0
0
0
0
Bit 7~0
STM Counter Low Byte Register bit 7 ~ bit 0
STM 10-bit Counter bit 7 ~ bit 0
STMDH Register
Rev. 1.00
Bit
7
6
5
4
3
2
1
0
Name
—
—
—
—
—
—
D9
D8
R/W
—
—
—
—
—
—
R
R
POR
—
—
—
—
—
—
0
0
Bit 7~2
Unimplemented, read as "0"
Bit 1~0
STM Counter High Byte Register bit 1 ~ bit 0
STM 10-bit Counter bit 9 ~ bit 8
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STMAL Register
Bit
7
6
5
4
3
2
1
0
Name
D7
D6
D5
D4
D3
D2
D1
D0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
0
0
0
0
0
0
0
Bit 7~0
STM CCRA Low Byte Register bit 7 ~ bit 0
STM 10-bit CCRA bit 7 ~ bit 0
STMAH 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 1~0
STM CCRA High Byte Register bit 1 ~ bit 0
STM 10-bit CCRA bit 9 ~ bit 8
Standard Type TM Operating Modes
The Standard Type TM can operate in one of five operating modes, Compare Match Output Mode,
PWM Output Mode, Single Pulse Output Mode, Capture Input Mode or Timer/Counter Mode. The
operating mode is selected using the STM1 and STM0 bits in the STMC1 register.
Compare Match Output Mode
To select this mode, bits STM1 and STM0 in the STMC1 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 STCCLR bit is low, there are two ways in which the counter can be cleared. One is when
a compare match from Comparator P, the other is when the CCRP bits are all zero which allows the
counter to overflow. Here both STMAF and STMPF interrupt request flags for Comparator A and
Comparator P respectively, will both be generated.
If the STCCLR bit in the STMC1 register is high then the counter will be cleared when a compare
match occurs from Comparator A. However, here only the STMAF interrupt request flag will be
generated even if the value of the CCRP bits is less than that of the CCRA registers. Therefore when
STCCLR is high no STMPF interrupt request flag will be generated. In the Compare Match Output
Mode, the CCRA cannot be set to "0". If the CCRA bits are all zero, the counter will overflow when
it reaches its maximum 10-bit, 3FF Hex, value, however here the STMAF interrupt request flag will
not be generated.
As the name of the mode suggests, after a comparison is made, the STM output pin, will change
state. The STM output pin condition however only changes state when an STMAF interrupt request
flag is generated after a compare match occurs from Comparator A. The STMPF interrupt request
flag, generated from a compare match occurs from Comparator P, will have no effect on the STM
output pin. The way in which the STM output pin changes state are determined by the condition of
the STIO1 and STIO0 bits in the STMC1 register. The STM output pin can be selected using the
STIO1 and STIO0 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 STM output pin, which is setup after
the STON bit changes from low to high, is setup using the STOC bit. Note that if the STIO1 and
STIO0 bits are zero then no pin change will take place.
Rev. 1.00
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Counter Value
Counter overflow
CCRP=0
0x�FF
STCCLR = 0; STM [1:0] = 00
CCRP > 0
Counter cleared b� CCRP value
CCRP > 0
Counter
Restart
Resume
CCRP
Pause
CCRA
Stop
Time
STON
STPAU
STPOL
CCRP Int.
flag ST�PF
CCRA Int.
flag ST�AF
Output pin set to
initial Level Low
if STOC=0
Output not affected b� ST�AF
flag. Remains High until reset b�
STON bit
Output Toggle with
ST�AF flag
Here STIO [1:0] = 11
Toggle Output select
Note STIO [1:0] = 10
Active High Output select
Output Inverts
when STPOL is high
Output Pin
Reset to Initial value
Output controlled b�
other pin-shared function
Compare Match Output Mode – STCCLR=0
Note: 1. With STCCLR=0 a Comparator P match will clear the counter
2. The STM output pin controlled only by the STMAF flag
3. The output pin reset to initial state by a STON bit rising edge
Rev. 1.00
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Counter Value
STCCLR = 1; STM [1:0] = 00
CCRA = 0
Counter overflow
CCRA > 0 Counter cleared b� CCRA value
0x�FF
CCRA=0
Resume
CCRA
Pause
Stop
Counter Restart
CCRP
Time
STON
STPAU
STPOL
No ST�AF flag
generated on
CCRA overflow
CCRA Int.
flag ST�AF
CCRP Int.
flag ST�PF
ST�PF not
generated
Output pin set to
initial Level Low
if STOC=0
Output does
not change
Output not affected b�
ST�AF flag. Remains High
until reset b� STON bit
Output Toggle with
ST�AF flag
Here STIO [1:0] = 11
Toggle Output select
Note STIO [1:0] = 10
Active High Output select
Output Inverts
when STPOL is high
Output Pin
Reset to Initial value
Output controlled b�
other pin-shared function
Compare Match Output Mode – STCCLR=1
Note: 1. With STCCLR=1 a Comparator A match will clear the counter
2. The STM output pin controlled only by the STMAF flag
3. The output pin reset to initial state by a STON rising edge
4. The STMPF flag is not generated when STCCLR=1
Rev. 1.00
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Timer/Counter Mode
To select this mode, bits STM1 and STM0 in the STMC1 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 STM
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 STM output pin is not used in
this mode, the pin can be used as a normal I/O pin or other pin-shared function by setting pin-share
function register.
PWM Output Mode
To select this mode, bits STM1 and STM0 in the STMC1 register should be set to 10 respectively
and also the STIO1 and STIO0 bits should be set to 10 respectively. The PWM function within
the STM 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
STM 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 output mode, the STCCLR bit has no effect as the
PWM period. Both of the CCRA and CCRP registers are used to generate the PWM waveform, one
register is used to clear the internal counter and thus control the PWM waveform frequency, while
the other one is used to control the duty cycle. Which register is used to control either frequency
or duty cycle is determined using the STDPX bit in the STMC1 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 STOC bit in the STMC1 register is used to
select the required polarity of the PWM waveform while the two STIO1 and STIO0 bits are used to
enable the PWM output or to force the STM output pin to a fixed high or low level. The STPOL bit
is used to reverse the polarity of the PWM output waveform.
• 10-bit STM, PWM Output Mode, Edge-aligned Mode, STDPX=0
CCRP
001b
010b
011b
100b
101b
110b
111b
000b
Period
128
256
384
512
640
768
896
1024
Duty
CCRA
If fSYS=4MHz, TM clock source is fSYS/4, CCRP=100b and CCRA =128,
The STM PWM output frequency=(fSYS/4)/512=fSYS/2048=1.9531kHz, duty=128/512=25%.
If the Duty value defined by the CCRA register is equal to or greater than the Period value, then the
PWM output duty is 100%.
• 10-bit STM, PWM Output Mode, Edge-aligned Mode, STDPX=1
CCRP
001b
010b
011b
100b
Period
Duty
101b
110b
111b
000b
768
896
1024
CCRA
128
256
384
512
640
The PWM output period is determined by the CCRA register value together with the STM clock
while the PWM duty cycle is defined by the CCRP register value.
Rev. 1.00
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Counter Value
STDPX = 0; STM [1:0] = 10
Counter cleared
b� CCRP
Counter Reset when
STON returns high
CCRP
Pause Resume
CCRA
Counter Stop if
STON bit low
Time
STON
STPAU
STPOL
CCRA Int.
flag ST�AF
CCRP Int.
flag ST�PF
ST� O/P Pin
(STOC=1)
ST� O/P Pin
(STOC=0)
PW� Dut� C�cle
set b� CCRA
PW� Period
set b� CCRP
PW� resumes
operation
Output controlled b�
Output Inverts
other pin-shared function
when STPOL = 1
PWM Output Mode – STDPX=0
Note: 1. Here STDPX=0 – Counter cleared by CCRP
2. A counter clear sets PWM Period
3. The internal PWM function continues running even when STIO[1:0]=00 or 01
4. The STCCLR bit has no influence on PWM operation
Rev. 1.00
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Counter Value
STDPX = 1; ST� [1:0] = 10
Counter cleared
b� CCRA
Counter Reset when
STON returns high
CCRA
Pause Resume
CCRP
Counter Stop if
STON bit low
Time
STON
STPAU
STPOL
CCRP Int.
flag ST�PF
CCRA Int.
flag ST�AF
ST� O/P Pin
(STOC=1)
ST� O/P Pin
(STOC=0)
PW� Dut� C�cle
set b� CCRP
PW� Period
set b� CCRA
PW� resumes
operation
Output controlled b�
Output Inverts
other pin-shared function
when STPOL = 1
PWM Output Mode – STDPX=1
Note: 1. Here STDPX=1 – Counter cleared by CCRA
2. A counter clear sets PWM Period
3. The internal PWM function continues even when STIO[1:0]=00 or 01
4. The STCCLR bit has no influence on PWM operation
Rev. 1.00
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Single Pulse Mode
To select this mode, bits STM1 and STM0 in the STMC1 register should be set to 10 respectively
and also the STIO1 and STIO0 bits should be set to 11 respectively. The Single Pulse Output Mode,
as the name suggests, will generate a single shot pulse on the STM output pin.
The trigger for the pulse output leading edge is a low to high transition of the STON bit, which can
be implemented using the application program. However in the Single Pulse Mode, the STON bit
can also be made to automatically change from low to high using the external STCK pin, which will
in turn initiate the Single Pulse output. When the STON bit transitions to a high level, the counter
will start running and the pulse leading edge will be generated. The STON bit should remain high
when the pulse is in its active state. The generated pulse trailing edge will be generated when the
STON bit is cleared to zero, which can be implemented using the application program or when a
compare match occurs from Comparator A.
S/W Command
SET“STON”
or
STCK Pin
Transition
CCRA
Leading Edge
CCRA
Trailing Edge
STON bit
1
0
STON bit
0
1
S/W Command
CLR“STON”
or
CCRA Compare
�atch
STP Output Pin
Pulse Width = CCRA Value
Single Pulse Generation
Counter Value
STM [1:0] = 10 ; STIO [1:0] = 11
Counter stopped
b� CCRA
Counter Reset when
STON returns high
CCRA
Pause
Counter Stops
b� software
Resume
CCRP
Time
STON
Software
Trigger
Auto. set b�
STCK pin
Cleared b�
CCRA match
STCK pin
Software
Trigger
Software
Trigger
Software
Software Trigger
Clear
STCK pin
Trigger
STPAU
STPOL
No CCRP Interrupts
generated
CCRP Int.
Flag ST�PF
CCRA Int.
Flag ST�AF
ST� O/P Pin
(STOC=1)
ST� O/P Pin
(STOC=0)
Output Inverts
when STPOL = 1
Pulse Width
set b� CCRA
Single Pulse Mode
Note: 1. Counter stopped by CCRA match
2. CCRP is not used
3. The pulse is triggered by setting the STON bit high
4. In the Single Pulse Mode, STIO [1:0] must be set to "11" and cannot be changed.
Rev. 1.00
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However a compare match from Comparator A will also automatically clear the STON bit and thus
generate the Single Pulse output trailing edge. In this way the CCRA value can be used to control the
pulse width. A compare match from Comparator A will also generate a STM interrupt. The counter
can only be reset back to zero when the STON bit changes from low to high when the counter
restarts. In the Single Pulse Mode CCRP is not used. The STCCLR and STDPX bits are not used in
this Mode.
Capture Input Mode
To select this mode bits STM1 and STM0 in the STMC1 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 measurement. The external signal
is supplied on the STP, whose active edge can be either a rising edge, a falling edge or both rising
and falling edges; the active edge transition type is selected using the STIO1 and STIO0 bits in
the STMC1 register. The counter is started when the STON bit changes from low to high which is
initiated using the application program.
When the required edge transition appears on the STP the present value in the counter will be
latched into the CCRA registers and a STM interrupt generated. Irrespective of what events occur on
the STP the counter will continue to free run until the STON 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 STM 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 STIO1 and STIO0 bits can
select the active trigger edge on the STP to be a rising edge, falling edge or both edge types. If
the STIO1 and STIO0 bits are both set high, then no capture operation will take place irrespective
of what happens on the STP, however it must be noted that the counter will continue to run. The
STCCLR and STDPX bits are not used in this Mode.
Rev. 1.00
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Counter Value
STM [1:0] = 01
Counter cleared
b� CCRP
Counter Counter
Stop
Reset
CCRP
YY
Pause
Resume
XX
Time
STON
STPAU
Active
edge
Active
edge
Active edge
ST� capture
pin STP
CCRA Int.
Flag ST�AF
CCRP Int.
Flag ST�PF
XX
CCRA Value
STIO [1:0]
Value
00 – Rising edge
YY
01 – Falling edge
XX
10 – Both edges
YY
11 – Disable Capture
Capture Input Mode
Note: 1. STM[1:0]=01 and active edge set by the STIO[1:0] bits
2. A TM Capture input pin active edge transfers the counter value to CCRA
3. The STCCLR and STDPX bits are not used
4. No output function – STOC and STPOL bits are not used
5. CCRP determines the counter value and the counter has a maximum count value when CCRP is equal to
zero.
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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 one external input pin and can drive one external output pin.
CCRP
10-bit Comparator P
fSYS/4
fSYS
fH/1�
fH/�4
fSUB
000
fSUB
101
001
PT�PF Interrupt
PTOC
b0~b9
010
011
10-bit Count-up Counter
100
110
PTCK
Comparator P �atch
PTON
PTPAU
Counter Clear
PTCCLR
b0~b9
111
PTCK�~PTCK0
10-bit Comparator A
CCRA
Output
Control
Polarit�
Control
Pin
Control
PT�1� PT�0
PTIO1� PTIO0
PTPOL
IOCN0
0
1
Comparator A �atch
PTP
PT�AF Interrupt
PTIO1� PTIO0
PTCAPTS
Edge
Detector
0
IOCN0
Pin
Control
1
Periodic Type TM Block Diagram
Periodic TM Operation
The Periodic Type TM core is a 10-bit count-up counter which is driven by a user selectable internal
or external clock source. There are also two internal comparators with the names, Comparator A
and Comparator P. These comparators will compare the value in the counter with CCRP and CCRA
registers. The CCRP comparator is 10-bit wide.
The only way of changing the value of the 10-bit counter using the application program, is to
clear the counter by changing the PTON 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 PTM 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 more than one output pin. All operating setup
conditions are selected using relevant internal registers.
Periodic Type TM Register Description
Overall operation of the Periodic Type 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 value 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
PTMC0
PTPAU
PTCK2
PTCK1
PTCK0
PTON
—
—
—
PTMC1
PTM1
PTM0
PTIO1
PTIO0
PTOC
PTPOL
PTMDL
D7
D6
D5
D4
D3
D2
D1
D0
PTMDH
—
—
—
—
—
—
D9
D8
PTCAPTS PTCCLR
PTMAL
D7
D6
D5
D4
D3
D2
D1
D0
PTMAH
—
—
—
—
—
—
D9
D8
PTMRPL
D7
D6
D5
D4
D3
D2
D1
D0
PTMRPH
—
—
—
—
—
—
D9
D8
10-bit Periodic TM Register List
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Ultrasonic Humidifier 8-Bit Flash MCU
PTMC0 Register
Bit
7
6
5
4
3
2
1
0
Name
PTPAU
PTCK2
PTCK1
PTCK0
PTON
—
—
—
R/W
R/W
R/W
R/W
R/W
R/W
—
—
—
POR
0
0
0
0
0
—
—
—
Bit 7PTPAU: PTM 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 PTM 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 6~4PTCK2~PTCK0: Select PTM Counter clock
000: fSYS/4
001: fSYS
010: fH/16
011: fH/64
100: fSUB
101: fSUB
110: PTCK rising edge clock
111: PTCK falling edge clock
These three bits are used to select the clock source for the PTM. The external pin clock
source can be chosen to be active on the rising or falling edge. The clock source fSYS is
the system clock, while fH and fSUB are other internal clocks, the details of which can
be found in the oscillator section.
Bit 3PTON: PTM Counter On/Off Control
0: Off
1: On
This bit controls the overall on/off function of the PTM. Setting the bit high enables
the counter to run, clearing the bit disables the PTM. Clearing this bit to zero will
stop the counter from counting and turn off the PTM 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 PTM is in the Compare Match Output Mode, PWM output Mode or Single Pulse
Output Mode then the PTM output pin will be reset to its initial condition, as specified
by the PTOC bit, when the PTON bit changes from low to high.
Bit 2~0
Rev. 1.00
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Ultrasonic Humidifier 8-Bit Flash MCU
PTMC1 Register
Bit
7
6
5
4
3
2
Name
PTM1
PTM0
PTIO1
PTIO0
PTOC
PTPOL
1
0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
0
0
0
0
0
0
0
PTCAPTS PTCCLR
Bit 7~6PTM1~PTM0: Select PTM Operating Mode
00: Compare Match Output Mode
01: Capture Input Mode
10: PWM Output Mode or Single Pulse Output Mode
11: Timer/Counter Mode
These bits setup the required operating mode for the PTM. To ensure reliable operation
the PTM should be switched off before any changes are made to the PTM1 and PTM0
bits. In the Timer/Counter Mode, the PTM output pin state is undefined.
Bit 5~4PTIO1~PTIO0: Select PTM pin PTP or PTCK function
Compare Match Output Mode
00: No change
01: Output low
10: Output high
11: Toggle output
PWM Output 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 PTP or PTCK
01: Input capture at falling edge of PTP or PTCK
10: Input capture at falling/rising edge of PTP or PTCK
11: Input capture disabled
Timer/Counter Mode
Unused
These two bits are used to determine how the PTM output pin changes state when a
certain condition is reached. The function that these bits select depends upon in which
mode the PTM is running.
In the Compare Match Output Mode, the PTIO1 and PTIO0 bits determine how the
PTM output pin changes state when a compare match occurs from the Comparator A.
The PTM 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 PTM output
pin should be setup using the PTOC bit in the PTMC1 register. Note that the output
level requested by the PTIO1 and PTIO0 bits must be different from the initial value
setup using the PTOC bit otherwise no change will occur on the PTM output pin when
a compare match occurs. After the PTM output pin changes state, it can be reset to its
initial level by changing the level of the PTON bit from low to high.
In the PWM Output Mode, the PTIO1 and PTIO0 bits determine how the PTM
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 PTIO1 and PTIO0 bits only after the TM has been switched off.
Unpredictable PWM outputs will occur if the PTIO1 and PTIO0 bits are changed
when the PTM is running.
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Bit 3PTOC: PTM PTP Output control bit
Compare Match Output Mode
0: Initial low
1: Initial high
PWM Output Mode/Single Pulse Output Mode
0: Active low
1: Active high
This is the output control bit for the PTM output pin. Its operation depends upon
whether PTM is being used in the Compare Match Output Mode or in the PWM
Output Mode/Single Pulse Output Mode. It has no effect if the PTM is in the Timer/
Counter Mode. In the Compare Match Output Mode it determines the logic level of
the PTM output pin before a compare match occurs. In the PWM Output Mode it
determines if the PWM signal is active high or active low.
Bit 2PTPOL: PTM PTP Output polarity Control
0: Non-invert
1: Invert
This bit controls the polarity of the PTP output pin. When the bit is set high the PTM
output pin will be inverted and not inverted when the bit is zero. It has no effect if the
PTM is in the Timer/Counter Mode.
Bit 1PTCAPTS: PTM Capture Trigger Source Selection
0: From PTP pin
1: From PTCK pin
Bit 0PTCCLR: Select PTM Counter clear condition
0: PTM Comparator P match
1: PTM Comparator 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 PTCCLR 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 PTCCLR bit is not
used in the PWM Output Mode, Single Pulse or Capture Input Mode.
PTMDL Register
Bit
7
6
5
4
3
2
1
0
Name
D7
D6
D5
D4
D3
D2
D1
D0
R/W
R
R
R
R
R
R
R
R
POR
0
0
0
0
0
0
0
0
2
1
0
Bit 7~0D7~D0: PTM Counter Low Byte Register bit 7 ~ bit 0
PTM 10-bit Counter bit 7 ~ bit 0
PTMDH Register
Bit
7
6
5
4
3
Name
—
—
—
—
—
—
D9
D8
R/W
—
—
—
—
—
—
R
R
POR
—
—
—
—
—
—
0
0
Bit 7~2
Unimplemented, read as "0"
Bit 1~0D9~D8: PTM Counter High Byte Register bit 1 ~ bit 0
PTM 10-bit Counter bit 9 ~ bit 8
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PTMAL 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: PTM CCRA Low Byte Register bit 7 ~ bit 0
PTM 10-bit CCRA bit 7 ~ bit 0
PTMAH 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 1~0D9~D8: PTM CCRA High Byte Register bit 1 ~ bit 0
PTM 10-bit CCRA bit 9 ~ bit 8
PTMRPL 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: PTM CCRP Low Byte Register bit 7 ~ bit 0
PTM 10-bit CCRP bit 7 ~ bit 0
PTMRPH 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 1~0D9~D8: PTM CCRP High Byte Register bit 1 ~ bit 0
PTM 10-bit CCRP bit 9 ~ bit 8
Rev. 1.00
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Ultrasonic Humidifier 8-Bit Flash MCU
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 PTM1 and PTM0 bits in the PTMC1 register.
Compare Match Output Mode
To select this mode, bits PTM1 and PTM0 in the PTMC1 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 PTCCLR bit is low, there are two ways in which the counter can be cleared. One is when
a compare match from Comparator P, the other is when the CCRP bits are all zero which allows the
counter to overflow. Here both PTMAF and PTMPF interrupt request flags for Comparator A and
Comparator P respectively, will both be generated.
If the PTCCLR bit in the PTMC1 register is high then the counter will be cleared when a compare
match occurs from Comparator A. However, here only the PTMAF interrupt request flag will be
generated even if the value of the CCRP bits is less than that of the CCRA registers. Therefore when
PTCCLR is high no PTMPF interrupt request flag will be generated. In the Compare Match Output
Mode, the CCRA can not be cleared to zero.
If the CCRA bits are all zero, the counter will overflow when its reaches its maximum 10-bit, 3FF
Hex, value, however here the PTMAF interrupt request flag will not be generated.
As the name of the mode suggests, after a comparison is made, the PTM output pin, will change
state. The PTM output pin condition however only changes state when a PTMAF interrupt request
flag is generated after a compare match occurs from Comparator A. The PTMPF interrupt request
flag, generated from a compare match occurs from Comparator P, will have no effect on the PTM
output pin. The way in which the PTM output pin changes state are determined by the condition of
the PTIO1 and PTIO0 bits in the PTMC1 register. The PTM output pin can be selected using the
PTIO1 and PTIO0 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 PTM output pin, which is setup after
the PTON bit changes from low to high, is setup using the PTOC bit. Note that if the PTIO1 and
PTIO0 bits are zero then no pin change will take place.
Rev. 1.00
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Ultrasonic Humidifier 8-Bit Flash MCU
Counter Value
Counter overflow
CCRP > 0
Counter cleared by CCRP value
CCRP=0
0x3FF
CCRP > 0
PTCCLR = 0; PTM[1:0] = 00
Counter
Restart
Resume
CCRP
Pause
CCRA
Stop
Time
PTON
PTPAU
PTPOL
CCRP Int. Flag
PTMPF
CCRA Int. Flag
PTMAF
PTM O/P Pin
Output pin set to
initial Level Low if
PTOC=0
Output not affected by PTMAF
flag. Remains High until reset by
PTON bit
Output Toggle with
PTMAF flag
Here PTIO [1:0] = 11
Toggle Output select
Note PTIO [1:0] = 10 Active
High Output select
Output Inverts
when PTPOL is high
Output Pin
Reset to Initial value
Output controlled by other
pin-shared function
Compare Match Output Mode – PTCCLR=0
Note: 1. With PTCCLR=0 a Comparator P match will clear the counter
2. The PTM output pin is controlled only by the PTMAF flag
3. The output pin is reset to its initial state by a PTON bit rising edge
Rev. 1.00
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Ultrasonic Humidifier 8-Bit Flash MCU
Counter Value
PTCCLR = 1; PTM[1:0] = 00
CCRA = 0
Counter overflow
CCRA > 0 Counter cleared by CCRA value
0x3FF
CCRA=0
Resume
CCRA
Pause
Stop
Counter Restart
CCRP
Time
PTON
PTPAU
PTPOL
No PTMAF flag
generated on
CCRA overflow
CCRA Int. Flag
PTMAF
CCRP Int. Flag
PTMPF
PTMPF not
generated
Output does
not change
PTM O/P Pin
Output pin set
to initial Level
Low if PTOC=0
Output Toggle with
PTMAF flag
Here PTIO [1:0] = 11
Toggle Output select
Output not affected by
PTMAF flag. Remains High
until reset by PTON bit
Note PTIO [1:0] = 10
Active High Output select
Output Inverts
when PTPOL is high
Output Pin
Reset to Initial value
Output controlled by other
pin-shared function
Compare Match Output Mode – PTCCLR=1
Note: 1. With PTCCLR=1 a Comparator A match will clear the counter
2. The PTM output pin is controlled only by the PTMAF flag
3. The output pin is reset to its initial state by a PTON bit rising edge
4. A PTMPF flag is not generated when PTCCLR=1
Rev. 1.00
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Timer/Counter Mode
To select this mode, bits PTM1 and PTM0 in the PTMC1 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 PTM1 and PTM0 in the PTMC1 register should be set to 10 respectively.
The PWM function within the PTM 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 PTM 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 Output Mode, the PTCCLR 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. 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 PTOC bit in the PTMC1 register is used to
select the required polarity of the PWM waveform while the two PTIO1 and PTIO0 bits are used to
enable the PWM output or to force the PTM output pin to a fixed high or low level. The PTPOL bit
is used to reverse the polarity of the PWM output waveform.
• 10-bit PTM, PWM Output Mode, Edge-aligned Mode
CCRP
1~1023
0
Period
1~1023
1024
Duty
CCRA
If fSYS=12MHz, PTM clock source select fSYS/4, CCRP=512 and CCRA=128,
The PTM PWM output frequency=(fSYS/4)/512=fSYS/2048=5.8594kHz, duty=128/(2×256)=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. 1.00
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Ultrasonic Humidifier 8-Bit Flash MCU
Counter Value
PTM[1:0] = 10
Counter cleared by
CCRP
Counter Reset when
PTON returns high
CCRP
Pause
Resume
Counter Stop if
PTON bit low
CCRA
Time
PTON
PTPAU
PTPOL
CCRA Int. Flag
PTMAF
CCRP Int. Flag
PTMPF
PTM O/P Pin
(PTOC=1)
PTM O/P Pin
(PTOC=0)
PWM Duty Cycle
set by CCRA
PWM Period
set by CCRP
Output controlled by other
pin-shared function
PWM resumes
operation
Output Inverts
When PTPOL = 1
PWM Output Mode
Note: 1. Counter cleared by CCRP
2. A counter clear sets the PWM Period
3. The internal PWM function continues running even when PTIO[1:0]=00 or 01
4. The PTCCLR bit has no influence on PWM operation
Rev. 1.00
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Ultrasonic Humidifier 8-Bit Flash MCU
Single Pulse Mode
To select this mode, bits PTM1 and PTM0 in the PTMC1 register should be set to 10 respectively
and also the PTIO1 and PTIO0 bits should be set to 11 respectively. The Single Pulse Output Mode,
as the name suggests, will generate a single shot pulse on the PTM output pin.
The trigger for the pulse output leading edge is a low to high transition of the PTON bit, which can
be implemented using the application program. However in the Single Pulse Mode, the PTON bit
can also be made to automatically change from low to high using the external PTCK pin, which will
in turn initiate the Single Pulse output. When the PTON bit transitions to a high level, the counter
will start running and the pulse leading edge will be generated. The PTON bit should remain high
when the pulse is in its active state. The generated pulse trailing edge will be generated when the
PTON 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 PTON bit and thus
generate the Single Pulse output trailing edge. In this way the CCRA value can be used to control the
pulse width. A compare match from Comparator A will also generate a PTM interrupt. The counter
can only be reset back to zero when the PTON bit changes from low to high when the counter
restarts. In the Single Pulse Mode CCRP is not used. The PTCCLR bit is not used in this Mode.
S/W Command
SET“PTON”
or
PTCK Pin
Transition
CCRA
Leading Edge
CCRA
Trailing Edge
PTON bit
0à1
PTON bit
1à0
S/W Command
CLR“PTON”
or
CCRA Compare
Match
PTP Output Pin
Pulse Width = CCRA Value
Single Pulse Generation
Rev. 1.00
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Ultrasonic Humidifier 8-Bit Flash MCU
Counter Value
PTM[1:0] = 10 ; PTIO[1:0] = 11
Counter stopped by
CCRA
Counter Reset when
PTON returns high
CCRA
Pause
Counter Stops by
software
Resume
CCRP
Time
PTON
Software
Trigger
Auto. set by
PTCK pin
Software
Trigger
Cleared by
CCRA match
PTCK pin
Software
Software Trigger
Clear
Software
Trigger
PTCK pin
Trigger
PTPAU
PTPOL
CCRP Int. Flag
PTMPF
No CCRP Interrupts
generated
CCRA Int. Flag
PTMAF
PTM O/P Pin
(PTOC=1)
PTM O/P Pin
(PTOC=0)
Output Inverts
when PTPOL = 1
Pulse Width set
by CCRA
Single Pulse Mode
Note: 1. Counter stopped by CCRA
2. CCRP is not used
3. The pulse is triggered by the PTCK pin or by setting the PTON bit high
4. A PTCK pin active edge will automatically set the PTON bit high
5. In the Single Pulse Mode, PTIO[1:0] must be set to "11" and cannot be changed.
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Capture Input Mode
To select this mode bits PTM1 and PTM0 in the PTMC1 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 PTP or PTCK pin which is selected using the PTCAPTS bit in the PTMC1 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 PTIO1 and PTIO0 bits in the PTMC1 register.
The counter is started when the PTON bit changes from low to high which is initiated using the
application program.
When the required edge transition appears on the PTP or PTCK pin the present value in the counter
will be latched into the CCRA registers and a PTM interrupt generated. Irrespective of what events
occur on the PTP or PTCK pin, the counter will continue to free run until the PTON 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 PTM 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 PTIO1 and PTIO0 bits can select the active trigger edge on the PTP or PTCK pin to be a rising
edge, falling edge or both edge types. If the PTIO1 and PTIO0 bits are both set high, then no capture
operation will take place irrespective of what happens on the PTP or PTCK pin, however it must be
noted that the counter will continue to run.
As the PTP or PTCK pin is pin shared with other functions, care must be taken if the PTM 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 PTCCLR, PTOC and PTPOL bits are not
used in this Mode.
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Counter Value
PTM[1:0] = 01
Counter cleared by
CCRP
Counter
Stop
Counter
Reset
CCRP
YY
Resume
Pause
XX
Time
PTON
PTPAU
Active
edge
Active
edge
Active edge
PTM Capture Pin
PTP or PTCK
CCRA Int. Flag
PTMAF
CCRP Int. Flag
PTMPF
CCRA Value
PTIO [1:0] Value
XX
00 - Rising edge
YY
XX
01 - Falling edge 10 - Both edges
YY
11 - Disable Capture
Capture Input Mode
Note: 1. PTM[1:0]=01 and active edge set by the PTIO[1:0] bits
2. A PTM Capture input pin active edge transfers the counter value to CCRA
3. PTCCLR bit not used
4. No output function – PTOC and PTPOL 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. 1.00
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Ultrasonic Humidifier 8-Bit Flash MCU
Nebuliser Resonance Detector
Please refer Holtek Applicatoin Notes.
Water Shortage Protection
Please refer Holtek Applicatoin Notes.
Over Current/Voltage Protection
The device includes an over current/voltage protection function which provides an over current or
over voltage protection protection mechanism for applications. The current on the OCVPAI0 pin
is converted to a relevant voltage level according to the current value using the OCVP operational
amplifier. It is then compared with a reference voltage generated by an 8-bit D/A converter. The
voltage on the OCVPCI pin is compared with a reference voltage generated by the 8-bit D/A converter.
When the OCVPF flag changes from 0 to 1 and if the corresponding interrupt control is enabled, an
OCVP interrupt will be generated to indicate a specific current or voltage condition has occurred.
VREF
VDD
OCVPEN
OCVPDA[7:0]
8-bit
DAC
OCVPVRS
S0
OCVPAI0
Pin
Control
S1
OCVPS[1:0]
S3
OCVPCOUT
OCVPEN
S2
S4
S5
OCVPO
OCVPEN
fDEB=fSYS
CMP
Debounce
OPA
R1
OCVPINT
OCVPSPOL
OCVPCI
OCVPCHY
2kΩ or 4kΩ
OCVPDEB[2:0]
OCVPCPS
OCVPG2XEN
S6
OCVPSWn
(n=0~6)
R2
S7
OCVPSW7
OCVPG[2:0]
OCVP Block Diagram
OCVP Operation
The OCVP circuit is used to prevent the input current or voltage from being in an unexpected level
range. The current on the OCVPAI0 pin is converted to a voltage and then amplified by the OCVP
operational amplifier with a programmable gain from 1 to 65 selected by the OCVPG2~OCVPG0
bits in the OCVPC2 register. This is known as the Programmable Gain Amplifier or PGA. This
PGA can also be configured to operate in the non-inverting, inverting or input offset cancellation
mode determined by the OCVPSW7~OCVPSW0 bits in the OCVPC0 register. After the current
is converted and amplified to a specific voltage level, it will be compared with a reference voltage
provided by an 8-bit D/A converter. The voltage on the OCVPCI pin is also can be selected to
compare with a reference provided by the 8-bit D/A converter.
To compare the OCVPAO output signal or the OCVPCI input signal with the D/A converter output
voltage is selected using the OCVPCPS bit in the OCVPC1 register. The 8-bit D/A converter power
can be supplied by the external power pin, VDD or VREF, selected by the OCVPVRS bit in the
OCVPC1 register. The comparator output, OCVPCOUT, will first be filtered with a certain debounce time period selected by the OCVPDEB2~OCVPDEB0 bits in the OCVPC2 register. Then
a filtered OCVP digital comparator output, OCVPO, is obtained to indicate whether a user-defined
current or voltage condition occurs or not.
Rev. 1.00
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If the OCVPSPOL bit is cleared to 0 and the comparator inputs force the OCVPO bit to change from 0
to 1, or if the OCVPSPOL bit is set to 1 and the comparator inputs force the OCVPO bit changes from
1 to 0, the corresponding interrupt will be generated if the relevant interrupt control bit is enabled.
It is important to note that, only an OCVPINT rising edge can trigger an OCVP interrupt request, so
the OCVPSPOL bit must be properly configured according to user’s application requirements. The
comparator in the OCVP circuit also has hysteresis function controlled by OCVPCHY bit.
Note that the debounce clock, fDEB, comes from the system clock, fSYS. The DAC output voltage is
controlled by the OCVPDA register and the DAC output is defined as below:
DAC VOUT=(DAC reference voltage/256) × D[7:0]
OCVP Control Registers
Overall operation of the OCVP function is controlled using several registers. The CTRL2 register
is used to select the OCVP input signal input pin. One register is used to provide the reference
voltages for the OCVP circuit. Two registers are used for the operational amplifier and comparator
input offset calibration. The remaining three registers are control registers which control the
OCVP function, D/A converter reference voltage select, switches on/off control, PGA gain select,
comparator non-inverting input select, comparator de-bounce time, comparator hysteresis function
and comparator output polarity control, etc. For a more detailed description regarding the input
offset voltage cancellation procedures, refer to the corresponding input offset cancellation sections.
Bit
Register
Name
7
6
5
4
3
2
1
0
CTRL2
—
—
—
—
—
—
OCVPS1
OCVPS0
OCVPDA
D7
D6
D5
D4
D3
D2
D1
D0
OCVPC0
OCVPSW7
OCVPSW6
OCVPSW5
OCVPSW4
OCVPSW3
OCVPSW2
OCVPSW1
OCVPSW0
OCVPC1
OCVPEN
OCVPCHY
OCVPO
OCVPSPOL
—
—
OCVPCPS
OCVPVRS
OCVPC2
—
OCVPG2XEN
OCVPG2
OCVPG1
OCVPG0
OCVPDEB2 OCVPDEB1 OCVPDEB0
OCVPOCAL OCVPOOFM
OCVPORSP
OCVPOOF5 OCVPOOF4 OCVPOOF3 OCVPOOF2 OCVPOOF1 OCVPOOF0
OCVPCCAL OCVPCOUT
OCVPCOFM
OCVPCRSP OCVPCOF4
OCVPCOF3 OCVPCOF2 OCVPCOF1 OCVPCOF0
OCVP Register List
CTRL2 Register
Rev. 1.00
Bit
7
6
5
4
3
2
Name
—
—
—
—
—
—
R/W
—
—
—
—
—
—
R/W
R/W
POR
—
—
—
—
—
—
0
0
Bit 7~2
Unimplemented, read as "0"
Bit 1~0
OCVPS1 ~ OCVPS0: OCVPAI0 Input Source Pin Selection
00: OCVPAI0 on PA4
01: OCVPAI0 on PA3
10: OCVPAI0 on PA6
11: OCVPAI0 on PA7
86
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0
OCVPS1 OCVPS0
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Ultrasonic Humidifier 8-Bit Flash MCU
OCVPC0 Register
Bit
Name
7
6
5
4
3
2
1
0
OCVPSW7 OCVPSW6 OCVPSW5 OCVPSW4 OCVPSW3 OCVPSW2 OCVPSW1 OCVPSW0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
1
1
0
0
1
0
0
0
Bit 7OCVPSW7: OCVP switch S7 on/off control
0: Off
1: On
Bit 6OCVPSW6: OCVP switch S6 on/off control
0: Off
1: On
Bit 5OCVPSW5: OCVP switch S5 on/off control
0: Off
1: On
Bit 4OCVPSW4: OCVP switch S4 on/off control
0: Off
1: On
Bit 3OCVPSW3: OCVP switch S3 on/off control
0: Off
1: On
Bit 2OCVPSW2: OCVP switch S2 on/off control
0: Off
1: On
Bit 1OCVPSW1: OCVP switch S1 on/off control
0: Off
1: On
Bit 0OCVPSW0: OCVP switch S0 on/off control
0: Off
1: On
OCVPC1 Register
Bit
Name
7
6
5
OCVPEN OCVPCHY OCVPO
4
3
2
OCVPSPOL
—
—
1
0
OCVPCPS OCVPVRS
R/W
R/W
R/W
R
R/W
—
—
R/W
R/W
POR
0
0
0
0
—
—
0
0
Bit 7OCVPEN: OCVP function enable control
0: Disable
1: Enable
When this bit is cleared to 0, the overall OCVP operation will be disabled and the
comparator output, OCVPCOUT, will be equal to 0.
Bit 6OCVPCHY: OCVP Comparator Hysteresis function control
0: Disable
1: Enable
Bit 5OCVPO: OCVP Comparator debounce output
This bit is the debounce version of the OCVPCOUT bit.
Bit 4OCVPSPOL: OCVPO polarity control
0: Non-invert
1: Invert
Bit 3~2
Rev. 1.00
Unimplemented, read as "0"
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Bit 1OCVPCPS: OCVP Comparator non-inverting input selection
0: From OCVPAO signal
1: From OCVPCI pin
Bit 0OCVPVRS: OCVP D/A Converter reference voltage selection
0: From VDD
1: From VREF pin
OCVPC2 Register
Bit
7
Name
—
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
6
5
4
3
2
1
0
OCVPG2XEN OCVPG2 OCVPG1 OCVPG0 OCVPDEB2 OCVPDEB1 OCVPDEB0
Unimplemented, read as "0"
Bit 6OCVPG2XEN: R2/R1 ratio doubling enable control
0: Disable (R1=4kΩ)
1: Enable (R1=2kΩ)
When this bit is 1, the R2/R1 ratio selected by the OCVPG2~OCVPG0 bits will be
doubled.
Bit 5~3OCVPG2~OCVPG0: PGA R2/R1 ratio selection
000: R2/R1=1
001: R2/R1=4
010: R2/R1=6
011: R2/R1=10
100: R2/R1=15
101: R2/R1=25
110: R2/R1=40
111: R2/R1=65
The internal resistors, R1 and R2, should be used when the gain is determined by
these bits. This means the S4 or S5 switch together with the S7 switch should be on.
Otherwise, the gain accuracy will not be guaranteed. When the OCVPG2XEN bit is
set to 1 to enable the R2/R1 ratio doubling function, the above R2/R1 values will be
doubled. The calculating formula of the PGA gain for the inverting and non-inverting
mode is described in the "Input Voltage Range" section.
Bit 2~0OCVPDEB2~OCVPDEB0: OCVP Comparator output debounce time control
000: Bypass, no debounce
001: (1~2) × tDEB
010: (3~4) × tDEB
011: (7~8) × tDEB
100: (15~16) × tDEB
101: (31~32) × tDEB
110: (63~64) × tDEB
111: (127~128) × tDEB
Note: fDEB=fSYS, tDEB=1/fDEB
OCVPDA Register
Bit
7
6
5
4
3
2
1
0
Name
D7
D6
D5
D4
D3
D2
D1
D0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
0
0
0
0
0
0
0
Bit 7~0
Rev. 1.00
OCVP D/A Converter Data Register bit 7 ~ bit 0
OCVP D/A Converter Output=(DAC reference voltage/256) × D[7:0]
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OCVPOCAL Register
Bit
7
6
5
4
3
2
1
0
Name OCVPOOFM OCVPORSP OCVPOOF5 OCVPOOF4 OCVPOOF3 OCVPOOF2 OCVPOOF1 OCVPOOF0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
0
1
0
0
0
0
0
Bit 7OCVPOOFM: OCVP Operational Amplifier operating mode selection
0: Normal operating mode
1: Offset cancellation mode
This bit is used to select the OCVP operating mode. To select the operational amplifier
input offset cancellation mode, the OCVPSW7~OCVPSW0 bits must first be set to
28H and then the OCVPOOFM bit must be set to 1 followed by the OCVPCOFM
bit being cleared to 0. Refer to the "Operational Amplifier Input Offset Cancellation"
section for the detailed offset cancellation procedures.
Bit 6OCVPORSP: OCVP Operational Amplifier input offset voltage cancellation reference
selection
0: Operational amplifier inverting input is selected
1: Operational amplifier non-verting input is selected
Bit 5~0OCVPOOF5~OCVPOOF0: OCVP Operational Amplifier input offset voltage cancellation
value
This 6-bit field is used to perform the operational amplifier input offset cancellation
operation and the value for the OCVP operational amplifier input offset cancellation
can be restored into this bit field. More detailed information is described in the
"Operational Amplifier Input Offset Cancellation" section.
OCVPCCAL Register
Bit
7
6
5
4
3
2
1
0
Name
OCVPCOUT
OCVPCOFM
OCVPCRSP
OCVPCOF4
OCVPCOF3
OCVPCOF2
OCVPCOF1
OCVPCOF0
R/W
R
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
0
0
1
0
0
0
0
Bit 7OCVPCOUT: OCVP Comparator output
0: Non-verting input voltage < DAC output voltage
1: Non-verting input voltage > DAC output voltage
This bit is used to indicate whether the non-verting input voltage is greater than the
DAC output voltage. If the OCVPCOUT is set to 1, the non-verting input voltage is
greater than the DAC output voltage. Otherwise, the non-verting input voltage is less
than the DAC output voltage. This bit value can be output on the OCVPCOUT pin.
Bit 6OCVPCOFM: OCVP Comparator operating mode selection
0: Normal operating mode
1: Offset cancellation mode
This bit is used to select the OCVP comparator operating mode. To select the
comparator input offset cancellation mode, the OCVPSW7~OCVPSW0 bits must
first be set to 28H and then the OCVPCOFM bit must be set to 1 followed by
the OCVPOOFM bit being cleared to 0. Refer to the "Comparator Input Offset
Cancellation" section for the detailed offset cancellation procedures.
Bit 5OCVPCRSP: OCVP Comparator input offset voltage cancellation reference selection
0: Inverting input as the reference input
1: Non-inverting input is selected as the reference input
Bit 4~0
Rev. 1.00
OCVPCOF4~OCVPCOF0: OCVP Comparator input offset voltage cancellation value
This 5-bit field is used to perform the comparator input offset cancellation operation
and the value for the OCVP comparator input offset cancellation can be restored into
this bit field. More detailed information is described in the "Comparator Input Offset
Cancellation" section.
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Input Voltage Range
Together with different PGA operating modes, the input voltage can be positive or negative to
provide diverse applications for the device. The PGA output for the positive or negative input voltage
is respectively calculated based on different formulas and described by the following examples.
• For VIN > 0, the PGA operates in the non-inverting mode and the PGA output is obtained using
the formula below:
V OUT  (1 
R2
) x V IN
R1
• When the PGA operates in the non-inverting mode, a unity gain buffer is provided. If
OCVPSW6~OCVPSW4 bits are set to "000", the PGA gain will be 1 and the PGA will act as a unity
gain buffer. The switches S6, S5 and S4 will be off internally and the output voltage of PGA is:
VOUT  VIN
• If S3 and S4 are on, the input node is OCVPAI0. For input voltage 0 >VIN >-0.4, the PGA operates
in the inverting mode and the PGA output is obtained using the formula below. Note that if the
input voltage VIN is negative, it can not be lower than -0.4V which will result in current leakage.
V OUT  
R2
x V IN
R1
Offset Calibration
To operate in the input offset cancellation mode for the OCVP circuit, the OCVPSW7~OCVPSW0
bits should first be set to 28H. For operational amplifier and comparator input offset cancellation, the
procedures are similar except for setting the respective control bits.
Operational Amplifier Input Offset Cancellation
Step 1. Set OCVPSW [7:0]=28H (S3 and S5 are on, other switches are off), OCVPOOFM=1,
OCVPCOFM=0 and OCVPORSP=1, the OCVP will operate in the operational amplifier
input offset cancellation mode.
Step 2. Set OCVPDA [7:0]=40H
Step 3. Set OCVPOOF [5:0]=000000 and read the OCVPCOUT bit.
Step 4. Increase the OCVPOOF [5:0] value by 1 and then read the OCVPCOUT bit.
If the OCVPCOUT bit state has not changed, then repeat Step 4 until the OCVPCOUT bit
state has changed.
If the OCVPCOUT bit state has changed, record the OCVPOOF value as VOOS1 and then
go to Step 5.
Step 5. Set OCVPOOF [5:0]=111111 and read the OCVPCOUT bit.
Step 6. Decrease the OCVPOOF [5:0] value by 1 and then read the OCVPCOUT bit.
If the OCVPCOUT bit state has not changed, then repeat Step 6 until the OCVPCOUT bit
state has changed.
If the OCVPCOUT bit state has changed, record the OCVPOOF value as VOOS2 and then
go to Step 7.
Step 7. Restore the operational amplifier input offset cancellation value VOOS into the OCVPOOF
[5:0] bit field. The offset cancellation procedure is now finished.
Where VOOS 
Rev. 1.00
VOOS1  VOOS�
�
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Ultrasonic Humidifier 8-Bit Flash MCU
Comparator input Offset Cancellation
Before the offset calibration, the hysteresis voltage should be zero by setting the OCVPCHY bit to 0.
Step 1. Set OCVPSW [7:0]=28H, OCVPCOFM=1, OCVPOOFM=0 and OCVPCRSP=0, the OCVP
will now operate in the comparator input offset cancellation mode.
Step 2. Set OCVPDA [7:0]=40H
Step 3. Set OCVPCOF [4:0]=00000 and read the OCVPCOUT bit.
Step 4. Increase the OCVPCOF [4:0] value by 1 and then read the OCVPCOUT bit.
If the OCVPCOUT bit state has not changed, then repeat Step 4 until the OCVPCOUT bit
state has changed.
If the OCVPCOUT bit state has changed, record the OCVPCOF value as VCOS1 and then
go to Step 5.
Step 5. Set OCVPCOF [4:0]=11111 and read the OCVPCOUT bit.
Step 6. Decrease the OCVPCOF [4:0] value by 1 and then read the OCVPCOUT bit.
If the OCVPCOUT bit state has not changed, then repeat Step 6 until the OCVPCOUT bit
state has changed.
If the OCVPCOUT bit state has changed, record the OCVPCOF value as VCOS2 and then
go to Step 7.
Step 7. Restore the comparator input offset cancellation value VCOS into the OCVPCOF [4:0] bit
field. The offset cancellation procedure is now finished.
Where VCOS  VCOS1  VCOS�
�
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 LVD 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
interrupt functions. The external interrupt is generated by the action of the external INT0 and INT1
pins, while the internal interrupts are generated by various internal functions such as the Timer
Modules (TMs), Over Current/Voltage Protection function (OCVP), Time Base, LVD and EEPROM.
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 interrupt registers fall into three categories. The first is the INTC0~INTC2
registers which setup the primary interrupts, the second is the MFI0~MFI2 registers which setup the
Multi-function interrupts. Finally there is an INTEG register to setup the external interrupt trigger
edge type.
Each register contains a number of enable bits to enable or disable individual registers as well as
interrupt flags to indicate the presence of an interrupt request. The naming convention of these
follows a specific pattern. First is listed an abbreviated interrupt type, then the (optional) number of
that interrupt followed by either an "E" for enable/disable bit or "F" for request flag.
Rev. 1.00
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Enable Bit
Request Flag
Global
Function
EMI
—
—
OCVP
OCVPE
OCVPF
—
INTn Pin
INTnE
INTnF
n=0 or 1
Multi-function
MFnE
MFnF
n=0~2
Time Base
TBnE
TBnF
n=0 or 1
LVE
LVF
—
LVD
EEPROM
Timer Module
Notes
DEE
DEF
—
STMAE
STMAF
—
STMPE
STMPF
—
PTMAE
PTMAF
—
PTMPE
PTMPF
—
Interrupt Register Bit Naming Conventions
Bit
Register
Name
7
6
5
4
3
2
1
0
INTEG
—
—
—
—
INT1S1
INT1S0
INT0S1
INT0S0
INTC0
—
—
INT0F
OCVPF
—
INT0E
OCVPE
EMI
INTC1
TB0F
MF2F
MF1F
MF0F
TB0E
MF2E
MF1E
MF0E
INTC2
—
—
INT1F
TB1F
—
—
INT1E
TB1E
MFI0
—
—
STMAF
STMPF
—
—
STMAE
STMPE
MFI1
—
—
PTMAF
PTMPF
—
—
PTMAE
PTMPE
MFI2
—
—
DEF
LVF
—
—
DEE
LVE
Interrupt Register List
INTEG Register
Rev. 1.00
Bit
7
6
5
4
3
2
1
0
Name
—
—
—
—
INT1S1
INT1S0
INT0S1
INT0S0
R/W
—
—
—
—
R/W
R/W
R/W
R/W
POR
—
—
—
—
0
0
0
0
Bit 7 ~ 4 Unimplemented, read as "0"
Bit 3 ~ 2
INT1S1, INT1S0: Defines INT1 interrupt active edge
00: Disabled Interrupt
01: Rising Edge Interrupt
10: Falling Edge Interrupt
11: Dual Edge Interrupt
Bit 1 ~ 0
INT0S1, INT0S0: Defines INT0 interrupt active edge
00: Disabled Interrupt
01: Rising Edge Interrupt
10: Falling Edge Interrupt
11: Dual Edge Interrupt
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INTC0 Register
Bit
7
6
5
4
3
2
1
0
Name
—
—
INT0F
OCVPF
—
INT0E
OCVPE
EMI
R/W
—
—
R/W
R/W
—
R/W
R/W
R/W
POR
—
—
0
0
—
0
0
0
Bit 7~6
Unimplemented, read as "0"
Bit 5INT0F: External interrupt 0 request flag
0: No request
1: Interrupt request
Bit 4OCVPF: Over current/voltage protection interrupt request flag
0: No request
1: Interrupt request
Bit 3
Unimplemented, read as "0"
Bit 2 INT0E: External interrupt 0 control
0: Disable
1: Enable
Bit 1OCVPE: Over current/voltage protection interrupt control
0: Disable
1: Enable
Bit 0EMI: Global Interrupt Control
0: Disable
1: Enable
INTC1 Register
Bit
7
6
5
4
3
2
1
0
Name
TB0F
MF2F
MF1F
MF0F
TB0E
MF2E
MF1E
MF0E
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
TB0F: Time Base 0 request flag
0: No request
1: Interrupt request
Bit 6MF2F: Multi-function interrupt 2 request flag
0: No request
1: Interrupt request
Bit 5MF1F: Multi-function interrupt 1request flag
0: No request
1: Interrupt request
Bit 4MF0F: Multi-function interrupt 0 request flag
0: No request
1: Interrupt request
Bit 3 TB0E: Time Base 0 interrupt control
0: Disable
1: Enable
Bit 2MF2E: Multi-function interrupt 2 control
0: Disable
1: Enable
Bit 1MF1E: Multi-function interrupt 1 control
0: Disable
1: Enable
Bit 0MF0E: Multi-function interrupt 0 control
0: Disable
1: Enable
Rev. 1.00
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INTC2 Register
Bit
7
6
5
4
3
2
1
0
Name
—
—
INT1F
TB1F
—
—
INT1E
TB1E
R/W
—
—
R/W
R/W
—
—
R/W
R/W
POR
—
—
0
0
—
—
0
0
Bit 7~6
Unimplemented, read as "0"
Bit 5INT1F: External interrupt 1 request flag
0: No request
1: Interrupt request
Bit 4TB1F: Time Base 1 interrupt request flag
0: No request
1: Interrupt request
Bit 3~2
Unimplemented, read as "0"
Bit 1 INT1E: External interrupt 1 control
0: Disable
1: Enable
Bit 0TB1E: Time Base 1 interrupt control
0: Disable
1: Enable
MFI0 Register
Rev. 1.00
Bit
7
6
5
4
3
2
1
0
Name
—
—
STMAF
STMPF
—
—
STMAE
STMPE
R/W
—
—
R/W
R/W
—
—
R/W
R/W
POR
—
—
0
0
—
—
0
0
Bit 7 ~ 6
Unimplemented, read as "0"
Bit 5
STMAF: STM comparator A match interrupt request flag
0: No request
1: Interrupt request
Bit 4
STMPF: STM comparator P match interrupt request flag
0: No request
1: Interrupt request
Bit 3 ~ 2
Unimplemented, read as "0"
Bit 1
STMAE: STM comparator A match interrupt control
0: Disable
1: Enable
Bit 0
STMPE: STM comparator P match interrupt control
0: Disable
1: Enable
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Ultrasonic Humidifier 8-Bit Flash MCU
MFI1 Register
Bit
7
6
5
4
3
2
1
0
Name
—
—
PTMAF
PTMPF
—
—
PTMAE
PTMPE
R/W
—
—
R/W
R/W
—
—
R/W
R/W
POR
—
—
0
0
—
—
0
0
Bit 7 ~ 6
Unimplemented, read as "0"
Bit 5
PTMAF: PTM comparator A match interrupt request flag
0: No request
1: Interrupt request
Bit 4
PTMPF: PTM comparator P match interrupt request flag
0: No request
1: Interrupt request
Bit 3 ~ 2
Unimplemented, read as "0"
Bit 1
PTMAE: PTM comparator A match interrupt control
0: Disable
1: Enable
Bit 0
PTMPE: PTM comparator P match interrupt control
0: Disable
1: Enable
MFI2 Register
Bit
7
6
5
4
3
2
1
0
Name
—
—
DEF
LVF
—
—
DEE
LVE
R/W
—
—
R/W
R/W
—
—
R/W
R/W
POR
—
—
0
0
—
—
0
0
Bit 7 ~ 6
Unimplemented, read as "0"
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 3~2
Unimplemented, read as "0"
Bit 1DEE: Data EEPROM interrupt control
0: Disable
1: Enable
Bit 0LVE: LVD interrupt control
0: Disable
1: Enable
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Interrupt Operation
When the conditions for an interrupt event occur, such as a TM Comparator P or Comparator A
match 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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Ultrasonic Humidifier 8-Bit Flash MCU
EMI auto disabled
in ISR
Legend
xxF
Request Flag, no auto reset in ISR
xxF
Request Flag, auto reset in ISR
xxE
Enable Bits
Interrupt
Name
OCVP
Request
Flags
OCVPF
Enable
Bits
OCVPE
Master
Enable
EMI
INT0 Pin
INT0F
INT0E
EMI
08H
M. Funct. 0
MF0F
MF0E
EMI
10H
Vector
Priority
04H
High
STM P
STMPF
STMPE
STM A
STMAF
STMAE
PTM P
PTMPF
PTMPE
PTM A
PTMAF
PTMAE
M. Funct. 1
MF1F
MF1E
EMI
14H
M. Funct. 2
MF2F
MF2E
EMI
18H
Time Base 0
TB0F
TB0E
EMI
1CH
Time Base 1
TB1F
TB1E
EMI
20H
INT1 Pin
INT1F
INT1E
EMI
24H
LVD
LVF
LVE
EEPROM
DEF
DEE
Interrupts contained within
Multi-Function Interrupts
Low
Interrupt Structure
External Interrupts
The external interrupts are controlled by signal transitions on the pins INT0~INT1. An external
interrupt request will take place when the external interrupt request flags, INT0F~INT1F, are set,
which will occur when a transition, whose type is chosen by the edge select bits, appears on the
external interrupt pins. To allow the program to branch to its respective interrupt vector address, the
global interrupt enable bit, EMI, and respective external interrupt enable bit, INT0E~INT1E, must
first be set. Additionally the correct interrupt edge type must be selected using the INTEG register to
enable the external interrupt function and to choose the trigger edge type. As the external interrupt
pins are pin-shared with I/O pins, they can only be configured as external interrupt pins if their
external interrupt enable bit in the corresponding interrupt register has been set. The pin must also be
setup as an input by setting the corresponding bit in the port control register as well as the relevant
pin-shared function selection bits. When the interrupt is enabled, the stack is not full and the correct
transition type appears on the external interrupt pin, a subroutine call to the external interrupt vector,
will take place. When the interrupt is serviced, the external interrupt request flags, INT0F~INT1F,
will be automatically reset and the EMI bit will be automatically cleared to disable other interrupts.
Note that any pull-high resistor selections on the external interrupt pins will remain valid even if the
pin is used as an external interrupt input.
The INTEG register is used to select the type of active edge that will trigger the external interrupt.
A choice of either rising or falling or both edge types can be chosen to trigger an external interrupt.
Note that the INTEG register can also be used to disable the external interrupt function.
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OCVP Interrupt
An OCVP interrupt request will take place when the OCVP Interrupt request flag, OCVPF, is set,
which occurs when the OCVP circuit detects a specific current or voltage condition. To allow the
program to branch to its respective interrupt vector address, the global interrupt enable bit, EMI,
and the OCVP Interrupt enable bit, OCVPE, must first be set. When the interrupt is enabled, the
stack is not full and a user-defined current or voltage condition occurs, a subroutine call to the
OCVP Interrupt vector, will take place. When the OCVP Interrupt is serviced, the EMI bit will be
automatically cleared to disable other interrupts and the OCVP interrupt request flag will be also
automatically cleared.
Multi-function Interrupts
Within the device there are three 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 and EEPROM Interrupt.
A Multi-function interrupt request will take place when any of the Multi-function interrupt request
flags, MFnF are set. The Multi-function interrupt flags will be set when any of their included
functions generate an interrupt request flag. To allow the program to branch to its respective interrupt
vector address, when the Multi-function interrupt is enabled and the stack is not full, and either one
of the interrupts contained within each of Multi-function interrupt occurs, a subroutine call to one of
the Multi-function interrupt vectors will take place. When the interrupt is serviced, the related MultiFunction request flag, will be automatically reset and the EMI bit will be automatically cleared to
disable other interrupts.
However, it must be noted that, although the Multi-function Interrupt flags will be automatically
reset when the interrupt is serviced, the request flags from the original source of the Multifunction interrupts, namely the TM Interrupts, LVD Interrupt and EEPROM Interrupt will not be
automatically reset and must be manually reset by the application program.
Time Base Interrupts
The function of the Time Base interrupts is to provide regular time signal in the form of an internal
interrupt. They are controlled by the overflow signals from their respective timer functions. When
these happens their respective interrupt request flags, TB0F or TB1F will be set. To allow the
program to branch to their respective interrupt vector addresses, the global interrupt enable bit, EMI
and Time Base enable bits, TB0E or TB1E, must first be set. When the interrupt is enabled, the stack
is not full and the Time Base overflows, a subroutine call to their respective vector locations will
take place. When the interrupt is serviced, the respective interrupt request flag, TB0F or TB1F, will
be automatically reset and the EMI bit will be cleared to disable other interrupts.
The purpose of the Time Base Interrupt is to provide an interrupt signal at fixed time periods. Their
clock sources originate from the internal clock source fTB. This fTB input clock passes through a
divider, the division ratio of which is selected by programming the appropriate bits in the TBC
register to obtain longer interrupt periods whose value ranges. The clock source that generates fTB,
which in turn controls the Time Base interrupt period, can originate from several different sources
which is selected using the TBCK bit in the TBC register.
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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 bit
0: Disable
1: Enable
Bit 6TBCK: Select fTB Clock Source
0: fTBC
1: fSYS/4
Bit 5 ~ 4
TB11 ~ TB10: Select Time Base 1 Time-out Period
00: 212/fTB
01: 213/fTB
10: 214/fTB
11: 215/fTB
Bit 3
Unimplemented, read as "0"
Bit 2 ~ 0
TB02 ~ TB00: Select Time Base 0 Time-out Period
000: 28/fTB
001: 29/fTB
010: 210/fTB
011: 211/fTB
100: 212/fTB
101: 213/fTB
110: 214/fTB
111: 215/fTB
TB0�~TB00
fSYS/4
LIRC
fTBC
�
U
X
÷�8~�15
Time Base 0 Interrupt
÷�1�~�15
Time Base 1 Interrupt
fTB
TBCK bit
TB11~TB10
Time Base Interrupt
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Ultrasonic Humidifier 8-Bit Flash MCU
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, MF2E, must first be set. When the interrupt is
enabled, the stack is not full and an EEPROM Write cycle ends, a subroutine call to the respective
EEPROM Interrupt vector, will take place. When the EEPROM Interrupt is serviced, the EMI bit
will be automatically cleared to disable other interrupts, however only the Multi-function interrupt
request flag will be also automatically cleared. As the DEF flag will not be automatically cleared, it
has to be cleared by the application program.
LVD Interrupt
The LVD 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, and Low Voltage Interrupt
enable bit, LVE, and associated Multi-function interrupt enable bit, MF2E, 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 LVD 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 LVD interrupt request flag, LVF, will not be
automatically cleared, it has to be cleared by the application program.
TM Interrupts
The Standard and Periodic Type TMs each have two interrupts. All of the TM interrupts are
contained within the Multi-function Interrupts. For the different Type TMs there are two interrupt
request flags xTMPF and xTMAF and two enable bits xTMPE and xTMAE. 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 comparator A match situation happens.
To allow the program to branch to its respective interrupt vector address, the global interrupt enable
bit, EMI, and the respective TM Interrupt enable bit, and associated Multi-function interrupt enable
bit, MFnF, 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 TM 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.
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Ultrasonic Humidifier 8-Bit Flash MCU
Interrupt Wake-up Function
Each of the interrupt functions has the capability of waking up the microcontroller when in the
SLEEP or IDLE Mode. A wake-up is generated when an interrupt request flag changes from low to
high and is independent of whether the interrupt is enabled or not. Therefore, even though the device
is in the SLEEP or IDLE Mode and its system oscillator stopped, situations such as external edge
transitions on the external interrupt pins or a low power supply voltage may cause their respective
interrupt flag to be set high and consequently generate an interrupt. Care must therefore be taken if
spurious wake-up situations are to be avoided. If an interrupt wake-up function is to be disabled then
the corresponding interrupt request flag should be set high before the device enters the SLEEP or
IDLE Mode. The interrupt enable bits have no effect on the interrupt wake-up function.
Programming Considerations
By disabling the relevant interrupt enable bits, a requested interrupt can be prevented from being
serviced, however, once an interrupt request flag is set, it will remain in this condition in the
interrupt register until the corresponding interrupt is serviced or until the request flag is cleared by
the application program.
Where a certain interrupt is contained within a Multi-function interrupt, then when the interrupt
service routine is executed, as only the Multi-function interrupt request flags, MF0F~MF2F, will
be automatically cleared, the individual request flag for the function needs to be cleared by the
application program.
It is recommended that programs do not use the "CALL" instruction within the interrupt service
subroutine. Interrupts often occur in an unpredictable manner or need to be serviced immediately.
If only one stack is left and the interrupt is not well controlled, the original control sequence will be
damaged once a CALL subroutine is executed in the interrupt subroutine.
Every interrupt has the capability of waking up the microcontroller when it is in SLEEP or IDLE
Mode, the wake up being generated when the interrupt request flag changes from low to high. If it is
required to prevent a certain interrupt from waking up the microcontroller then its respective request
flag should be first set high before enter SLEEP or IDLE Mode.
As only the Program Counter is pushed onto the stack, then when the interrupt is serviced, if the
contents of the accumulator, status register or other registers are altered by the interrupt service
program, their contents should be saved to the memory at the beginning of the interrupt service
routine.
To return from an interrupt subroutine, either a RET or RETI instruction may be executed. The RETI
instruction in addition to executing a return to the main program also automatically sets the EMI
bit high to allow further interrupts. The RET instruction however only executes a return to the main
program leaving the EMI bit in its present zero state and therefore disabling the execution of further
interrupts.
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Low Voltage Detector – LVD
The device has a Low Voltage Detector function, also known as LVD. This enables the device to
monitor the power supply voltage, VDD, and provides 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 Detected
1: Low Voltage Detected
Bit 4LVDEN: Low Voltage Detector Control
0: Disable
1: Enable
Rev. 1.00
Bit 3 Unimplemented, read as "0"
Bit 2~0
VLVD2 ~ 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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Ultrasonic Humidifier 8-Bit Flash MCU
LVD Operation
The Low Voltage Detector function operates by comparing the power supply voltage, VDD, with a
pre-specified voltage level stored in the LVDC register. This has a range of between 2.0V and 4.0V.
When the power supply voltage, VDD, falls below this pre-determined value, the LVDO bit will be
set high indicating a low power supply voltage condition. The Low Voltage Detector function is
supplied by a reference voltage which will be automatically enabled. After enabling the Low Voltage
Detector, a time delay tLVDS should be allowed for the circuitry to stabilise before reading the LVDO
bit. Note also that as the VDD voltage may rise and fall rather slowly, at the voltage nears that of
VLVD, there may be multiple bit LVDO transitions.
VDD
VLVD
LVDEN
LVDO
tLVDS
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. 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.
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.
Options
Watchdog Timer Option
1
Rev. 1.00
Watchdog Timer Enable/disable Selection:
Controlled by WDTC register
Always enabled
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Application Circuits
+24V
L1
4.7μH
+5V
C1
4
24VIN
7
C3
104
+
8
PTP/PA1
VDD
OCVPAI0/INT0/PTCK/PA3
PA2/ICPCK
OCVPCI/INT1/STCK/PA5
PA0/ICPDA
VSS
5
2
Nebuliser
R1
20KΩ
R2
20KΩ
C5
104
R3
1Ω
+5V
C8
104
VIN
7805
GND
U2
2
C6 +
10μF/50V
6
C4
104
C2 HT45F3820_8SOP
10μF/10V
+24V
1
OCVP0AI0/STP/PA4/VREF
1
1
104/400V
U3
3
3
2
U1
CON1 +24V
2
1
Vout
3
C9
104
+ C7
10μF/10V
GND GND
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Instruction Set
Introduction
Central to the successful operation of any microcontroller is its instruction set, which is a set of
program instruction codes that directs the microcontroller to perform certain operations. In the case
of Holtek microcontroller, a comprehensive and flexible set of over 60 instructions is provided to
enable programmers to implement their application with the minimum of programming overheads.
For easier understanding of the various instruction codes, they have been subdivided into several
functional groupings.
Instruction Timing
Most instructions are implemented within one instruction cycle. The exceptions to this are branch,
call, or table read instructions where two instruction cycles are required. One instruction cycle is
equal to 4 system clock cycles, therefore in the case of an 8MHz system oscillator, most instructions
would be implemented within 0.5μs and branch or call instructions would be implemented within
1μs. Although instructions which require one more cycle to implement are generally limited to
the JMP, CALL, RET, RETI and table read instructions, it is important to realize that any other
instructions which involve manipulation of the Program Counter Low register or PCL will also take
one more cycle to implement. As instructions which change the contents of the PCL will imply a
direct jump to that new address, one more cycle will be required. Examples of such instructions
would be "CLR PCL" or "MOV PCL, A". For the case of skip instructions, it must be noted that if
the result of the comparison involves a skip operation then this will also take one more cycle, if no
skip is involved then only one cycle is required.
Moving and Transferring Data
The transfer of data within the microcontroller program is one of the most frequently used
operations. Making use of three kinds of MOV instructions, data can be transferred from registers to
the Accumulator and vice-versa as well as being able to move specific immediate data directly into
the Accumulator. One of the most important data transfer applications is to receive data from the
input ports and transfer data to the output ports.
Arithmetic Operations
The ability to perform certain arithmetic operations and data manipulation is a necessary feature of
most microcontroller applications. Within the Holtek microcontroller instruction set are a range of
add and subtract instruction mnemonics to enable the necessary arithmetic to be carried out. Care
must be taken to ensure correct handling of carry and borrow data when results exceed 255 for
addition and less than 0 for subtraction. The increment and decrement instructions INC, INCA, DEC
and DECA provide a simple means of increasing or decreasing by a value of one of the values in the
destination specified.
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Logical and Rotate Operation
The standard logical operations such as AND, OR, XOR and CPL all have their own instruction
within the Holtek microcontroller instruction set. As with the case of most instructions involving
data manipulation, data must pass through the Accumulator which may involve additional
programming steps. In all logical data operations, the zero flag may be set if the result of the
operation is zero. Another form of logical data manipulation comes from the rotate instructions such
as RR, RL, RRC and RLC which provide a simple means of rotating one bit right or left. Different
rotate instructions exist depending on program requirements. Rotate instructions are useful for serial
port programming applications where data can be rotated from an internal register into the Carry
bit from where it can be examined and the necessary serial bit set high or low. Another application
which rotate data operations are used is to implement multiplication and division calculations.
Branches and Control Transfer
Program branching takes the form of either jumps to specified locations using the JMP instruction
or to a subroutine using the CALL instruction. They differ in the sense that in the case of a
subroutine call, the program must return to the instruction immediately when the subroutine has
been carried out. This is done by placing a return instruction "RET" in the subroutine which will
cause the program to jump back to the address right after the CALL instruction. In the case of a JMP
instruction, the program simply jumps to the desired location. There is no requirement to jump back
to the original jumping off point as in the case of the CALL instruction. One special and extremely
useful set of branch instructions are the conditional branches. Here a decision is first made regarding
the condition of a certain data memory or individual bits. Depending upon the conditions, the
program will continue with the next instruction or skip over it and jump to the following instruction.
These instructions are the key to decision making and branching within the program perhaps
determined by the condition of certain input switches or by the condition of internal data bits.
Bit Operations
The ability to provide single bit operations on Data Memory is an extremely flexible feature of all
Holtek microcontrollers. This feature is especially useful for output port bit programming where
individual bits or port pins can be directly set high or low using either the "SET [m].i" or "CLR [m].
i" instructions respectively. The feature removes the need for programmers to first read the 8-bit
output port, manipulate the input data to ensure that other bits are not changed and then output the
port with the correct new data. This read-modify-write process is taken care of automatically when
these bit operation instructions are used.
Table Read Operations
Data storage is normally implemented by using registers. However, when working with large
amounts of fixed data, the volume involved often makes it inconvenient to store the fixed data in
the Data Memory. To overcome this problem, Holtek microcontrollers allow an area of Program
Memory to be set as a table where data can be directly stored. A set of easy to use instructions
provides the means by which this fixed data can be referenced and retrieved from the Program
Memory.
Other Operations
In addition to the above functional instructions, a range of other instructions also exist such as
the "HALT" instruction for Power-down operations and instructions to control the operation of
the Watchdog Timer for reliable program operations under extreme electric or electromagnetic
environments. For their relevant operations, refer to the functional related sections.
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Instruction Set Summary
The following table depicts a summary of the instruction set categorised according to function and
can be consulted as a basic instruction reference using the following listed conventions.
Table Conventions
x: Bits immediate data
m: Data Memory address
A: Accumulator
i: 0~7 number of bits
addr: Program memory address
Mnemonic
Description
Cycles
Flag Affected
Add Data Memory to ACC
Add ACC to Data Memory
Add immediate data to ACC
Add Data Memory to ACC with Carry
Add ACC to Data memory with Carry
Subtract immediate data from the ACC
Subtract Data Memory from ACC
Subtract Data Memory from ACC with result in Data Memory
Subtract Data Memory from ACC with Carry
Subtract Data Memory from ACC with Carry, result in Data Memory
Decimal adjust ACC for Addition with result in Data Memory
1
1Note
1
1
1Note
1
1
1Note
1
1Note
1Note
Z, C, AC, OV
Z, C, AC, OV
Z, C, AC, OV
Z, C, AC, OV
Z, C, AC, OV
Z, C, AC, OV
Z, C, AC, OV
Z, C, AC, OV
Z, C, AC, OV
Z, C, AC, OV
C
1
1
1
1Note
1Note
1Note
1
1
1
1Note
1
Z
Z
Z
Z
Z
Z
Z
Z
Z
Z
Z
Increment Data Memory with result in ACC
Increment Data Memory
Decrement Data Memory with result in ACC
Decrement Data Memory
1
1Note
1
1Note
Z
Z
Z
Z
Rotate Data Memory right with result in ACC
Rotate Data Memory right
Rotate Data Memory right through Carry with result in ACC
Rotate Data Memory right through Carry
Rotate Data Memory left with result in ACC
Rotate Data Memory left
Rotate Data Memory left through Carry with result in ACC
Rotate Data Memory left through Carry
1
1Note
1
1Note
1
1Note
1
1Note
None
None
C
C
None
None
C
C
Arithmetic
ADD A,[m]
ADDM A,[m]
ADD A,x
ADC A,[m]
ADCM A,[m]
SUB A,x
SUB A,[m]
SUBM A,[m]
SBC A,[m]
SBCM A,[m]
DAA [m]
Logic Operation
AND A,[m]
Logical AND Data Memory to ACC
OR A,[m]
Logical OR Data Memory to ACC
XOR A,[m]
Logical XOR Data Memory to ACC
ANDM A,[m]
Logical AND ACC to Data Memory
ORM A,[m]
Logical OR ACC to Data Memory
XORM A,[m]
Logical XOR ACC to Data Memory
AND A,x
Logical AND immediate Data to ACC
OR A,x
Logical OR immediate Data to ACC
XOR A,x
Logical XOR immediate Data to ACC
CPL [m]
Complement Data Memory
CPLA [m]
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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HT45F3820
Ultrasonic Humidifier 8-Bit Flash MCU
Mnemonic
Description
Cycles
Flag Affected
Move Data Memory to ACC
Move ACC to Data Memory
Move immediate data to ACC
1
1Note
1
None
None
None
Clear bit of Data Memory
Set bit of Data Memory
1Note
1Note
None
None
Jump unconditionally
Skip if Data Memory is zero
Skip if Data Memory is zero with data movement to ACC
Skip if bit i of Data Memory is zero
Skip if bit i of Data Memory is not zero
Skip if increment Data Memory is zero
Skip if decrement Data Memory is zero
Skip if increment Data Memory is zero with result in ACC
Skip if decrement Data Memory is zero with result in ACC
Subroutine call
Return from subroutine
Return from subroutine and load immediate data to ACC
Return from interrupt
2
1Note
1Note
1Note
1Note
1Note
1Note
1Note
1Note
2
2
2
2
None
None
None
None
None
None
None
None
None
None
None
None
None
Read table (specific page) to TBLH and Data Memory
Read table (current page) to TBLH and Data Memory
Read table (last page) to TBLH and Data Memory
2Note
2Note
2Note
None
None
None
No operation
Clear Data Memory
Set Data Memory
Clear Watchdog Timer
Pre-clear Watchdog Timer
Pre-clear Watchdog Timer
Swap nibbles of Data Memory
Swap nibbles of Data Memory with result in ACC
Enter power down mode
1
1Note
1Note
1
1
1
1Note
1
1
None
None
None
TO, PDF
TO, PDF
TO, PDF
None
None
TO, PDF
Data Move
MOV A,[m]
MOV [m],A
MOV A,x
Bit Operation
CLR [m].i
SET [m].i
Branch Operation
JMP addr
SZ [m]
SZA [m]
SZ [m].i
SNZ [m].i
SIZ [m]
SDZ [m]
SIZA [m]
SDZA [m]
CALL addr
RET
RET A,x
RETI
Table Read Operation
TABRD [m]
TABRDC [m]
TABRDL [m]
Miscellaneous
NOP
CLR [m]
SET [m]
CLR WDT
CLR WDT1
CLR WDT2
SWAP [m]
SWAPA [m]
HALT
Note: 1. For skip instructions, if the result of the comparison involves a skip then two cycles are required, if no
skip takes place only one cycle is required.
2. Any instruction which changes the contents of the PCL will also require 2 cycles for execution.
3. For the “CLR WDT1” and “CLR WDT2” instructions the TO and PDF flags may be affected by the
execution status. The TO and PDF flags are cleared after both “CLR WDT1” and “CLR WDT2”
instructions are consecutively executed. Otherwise the TO and PDF flags remain unchanged.
Rev. 1.00
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HT45F3820
Ultrasonic Humidifier 8-Bit Flash MCU
Instruction Definition
ADC A,[m]
Description
Operation
Affected flag(s)
Add Data Memory to ACC with Carry
The contents of the specified Data Memory, Accumulator and the carry flag are added.
The result is stored in the Accumulator.
ACC ← ACC + [m] + C
OV, Z, AC, C
ADCM A,[m]
Description
Operation
Affected flag(s)
Add ACC to Data Memory with Carry
The contents of the specified Data Memory, Accumulator and the carry flag are added. The result is stored in the specified Data Memory.
[m] ← ACC + [m] + C
OV, Z, AC, C
Add Data Memory to ACC
ADD A,[m]
Description
The contents of the specified Data Memory and the Accumulator are added.
The result is stored in the Accumulator.
Operation
Affected flag(s)
ACC ← ACC + [m]
OV, Z, AC, C
ADD A,x
Description
Operation
Affected flag(s)
Add immediate data to ACC
The contents of the Accumulator and the specified immediate data are added. The result is stored in the Accumulator.
ACC ← ACC + x
OV, Z, AC, C
ADDM A,[m]
Description
Operation
Affected flag(s)
Add ACC to Data Memory
The contents of the specified Data Memory and the Accumulator are added. The result is stored in the specified Data Memory.
[m] ← ACC + [m]
OV, Z, AC, C
AND A,[m]
Description
Operation
Affected flag(s)
Logical AND Data Memory to ACC
Data in the Accumulator and the specified Data Memory perform a bitwise logical AND operation. The result is stored in the Accumulator.
ACC ← ACC ″AND″ [m]
Z
AND A,x
Description
Operation
Affected flag(s)
Logical AND immediate data to ACC
Data in the Accumulator and the specified immediate data perform a bit wise logical AND operation. The result is stored in the Accumulator.
ACC ← ACC ″AND″ x
Z
ANDM A,[m]
Description
Operation
Affected flag(s)
Logical AND ACC to Data Memory
Data in the specified Data Memory and the Accumulator perform a bitwise logical AND
operation. The result is stored in the Data Memory.
[m] ← ACC ″AND″ [m]
Z
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HT45F3820
Ultrasonic Humidifier 8-Bit Flash MCU
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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HT45F3820
Ultrasonic Humidifier 8-Bit Flash MCU
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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HT45F3820
Ultrasonic Humidifier 8-Bit Flash MCU
JMP addr
Description
Operation
Affected flag(s)
Jump unconditionally
The contents of the Program Counter are replaced with the specified address. Program
execution then continues from this new address. As this requires the insertion of a dummy
instruction while the new address is loaded, it is a two cycle instruction.
Program Counter ← addr
None
MOV A,[m]
Description
Operation
Affected flag(s)
Move Data Memory to ACC
The contents of the specified Data Memory are copied to the Accumulator.
ACC ← [m]
None
MOV A,x
Description
Operation
Affected flag(s)
Move immediate data to ACC
The immediate data specified is loaded into the Accumulator.
ACC ← x
None
MOV [m],A
Description
Operation
Affected flag(s)
Move ACC to Data Memory
The contents of the Accumulator are copied to the specified Data Memory.
[m] ← ACC
None
NOP
Description
Operation
Affected flag(s)
No operation
No operation is performed. Execution continues with the next instruction.
No operation
None
OR A,[m]
Description
Operation
Affected flag(s)
Logical OR Data Memory to ACC
Data in the Accumulator and the specified Data Memory perform a bitwise
logical OR operation. The result is stored in the Accumulator.
ACC ← ACC ″OR″ [m]
Z
OR A,x
Description
Operation
Affected flag(s)
Logical OR immediate data to ACC
Data in the Accumulator and the specified immediate data perform a bitwise logical OR operation. The result is stored in the Accumulator.
ACC ← ACC ″OR″ x
Z
ORM A,[m]
Description
Operation
Affected flag(s)
Logical OR ACC to Data Memory
Data in the specified Data Memory and the Accumulator perform a bitwise logical OR operation. The result is stored in the Data Memory.
[m] ← ACC ″OR″ [m]
Z
RET
Description
Operation
Affected flag(s)
Return from subroutine
The Program Counter is restored from the stack. Program execution continues at the restored
address.
Program Counter ← Stack
None
Rev. 1.00
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HT45F3820
Ultrasonic Humidifier 8-Bit Flash MCU
RET A,x
Description
Operation
Affected flag(s)
Return from subroutine and load immediate data to ACC
The Program Counter is restored from the stack and the Accumulator loaded with the specified immediate data. Program execution continues at the restored address.
Program Counter ← Stack
ACC ← x
None
RETI
Description
Operation
Affected flag(s)
Return from interrupt
The Program Counter is restored from the stack and the interrupts are re-enabled by setting the
EMI bit. EMI is the master interrupt global enable bit. If an interrupt was pending when the RETI instruction is executed, the pending Interrupt routine will be processed before returning to the main program.
Program Counter ← Stack
EMI ← 1
None
RL [m]
Description
Operation
Affected flag(s)
Rotate Data Memory left
The contents of the specified Data Memory are rotated left by 1 bit with bit 7 rotated into bit 0.
[m].(i+1) ← [m].i; (i=0~6)
[m].0 ← [m].7
None
RLA [m]
Description
Operation
Affected flag(s)
Rotate Data Memory left with result in ACC
The contents of the specified Data Memory are rotated left by 1 bit with bit 7 rotated into bit 0.
The rotated result is stored in the Accumulator and the contents of the Data Memory remain
unchanged.
ACC.(i+1) ← [m].i; (i=0~6)
ACC.0 ← [m].7
None
RLC [m]
Description
Operation
Affected flag(s)
Rotate Data Memory left through Carry
The contents of the specified Data Memory and the carry flag are rotated left by 1 bit. Bit 7
replaces the Carry bit and the original carry flag is rotated into bit 0.
[m].(i+1) ← [m].i; (i=0~6)
[m].0 ← C
C ← [m].7
C
RLCA [m]
Description
Operation
Affected flag(s)
Rotate Data Memory left through Carry with result in ACC
Data in the specified Data Memory and the carry flag are rotated left by 1 bit. Bit 7 replaces the
Carry bit and the original carry flag is rotated into the bit 0. The rotated result is stored in the
Accumulator and the contents of the Data Memory remain unchanged.
ACC.(i+1) ← [m].i; (i=0~6)
ACC.0 ← C
C ← [m].7
C
RR [m]
Description
Operation
Affected flag(s)
Rotate Data Memory right
The contents of the specified Data Memory are rotated right by 1 bit with bit 0 rotated into bit 7.
[m].i ← [m].(i+1); (i=0~6)
[m].7 ← [m].0
None
Rev. 1.00
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HT45F3820
Ultrasonic Humidifier 8-Bit Flash MCU
RRA [m]
Description
Operation
Affected flag(s)
Rotate Data Memory right with result in ACC
Data in the specified Data Memory is rotated right by 1 bit with bit 0 rotated into bit 7. The rotated result is stored in the Accumulator and the contents of the Data Memory remain unchanged.
ACC.i ← [m].(i+1); (i=0~6)
ACC.7 ← [m].0
None
RRC [m]
Description
Operation
Affected flag(s)
Rotate Data Memory right through Carry
The contents of the specified Data Memory and the carry flag are rotated right by 1 bit. Bit 0
replaces the Carry bit and the original carry flag is rotated into bit 7.
[m].i ← [m].(i+1); (i=0~6)
[m].7 ← C
C ← [m].0
C
RRCA [m]
Description
Operation
Affected flag(s)
Rotate Data Memory right through Carry with result in ACC
Data in the specified Data Memory and the carry flag are rotated right by 1 bit. Bit 0 replaces the Carry bit and the original carry flag is rotated into bit 7. The rotated result is stored in the Accumulator and the contents of the Data Memory remain unchanged.
ACC.i ← [m].(i+1); (i=0~6)
ACC.7 ← C
C ← [m].0
C
SBC A,[m]
Description
Operation
Affected flag(s)
Subtract Data Memory from ACC with Carry
The contents of the specified Data Memory and the complement of the carry flag are
subtracted from the Accumulator. The result is stored in the Accumulator. Note that if the result of subtraction is negative, the C flag will be cleared to 0, otherwise if the result is
positive or zero, the C flag will be set to 1.
ACC ← ACC − [m] − C
OV, Z, AC, C
SBCM A,[m]
Description
Operation
Affected flag(s)
Subtract Data Memory from ACC with Carry and result in Data Memory
The contents of the specified Data Memory and the complement of the carry flag are subtracted from the Accumulator. The result is stored in the Data Memory. Note that if the result of subtraction is negative, the C flag will be cleared to 0, otherwise if the result is positive or zero, the C flag will be set to 1.
[m] ← ACC − [m] − C
OV, Z, AC, C
SDZ [m]
Description
Operation
Affected flag(s)
Skip if decrement Data Memory is 0
The contents of the specified Data Memory are first decremented by 1. If the result is 0 the following instruction is skipped. As this requires the insertion of a dummy instruction while the next instruction is fetched, it is a two cycle instruction. If the result is not 0 the program proceeds with the following instruction.
[m] ← [m] − 1
Skip if [m]=0
None
Rev. 1.00
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May 30, 2016
HT45F3820
Ultrasonic Humidifier 8-Bit Flash MCU
SDZA [m]
Description
Operation
Affected flag(s)
Skip if decrement Data Memory is zero with result in ACC
The contents of the specified Data Memory are first decremented by 1. If the result is 0, the following instruction is skipped. The result is stored in the Accumulator but the specified Data Memory contents remain unchanged. As this requires the insertion of a dummy
instruction while the next instruction is fetched, it is a two cycle instruction. If the result is not 0,
the program proceeds with the following instruction.
ACC ← [m] − 1
Skip if ACC=0
None
SET [m]
Description
Operation
Affected flag(s)
Set Data Memory
Each bit of the specified Data Memory is set to 1.
[m] ← FFH
None
SET [m].i
Description
Operation
Affected flag(s)
Set bit of Data Memory
Bit i of the specified Data Memory is set to 1.
[m].i ← 1
None
SIZ [m]
Description
Operation
Affected flag(s)
Skip if increment Data Memory is 0
The contents of the specified Data Memory are first incremented by 1. If the result is 0, the
following instruction is skipped. As this requires the insertion of a dummy instruction while the next instruction is fetched, it is a two cycle instruction. If the result is not 0 the program
proceeds with the following instruction.
[m] ← [m] + 1
Skip if [m]=0
None
SIZA [m]
Description
Operation
Affected flag(s)
Skip if increment Data Memory is zero with result in ACC
The contents of the specified Data Memory are first incremented by 1. If the result is 0, the following instruction is skipped. The result is stored in the Accumulator but the specified
Data Memory contents remain unchanged. As this requires the insertion of a dummy
instruction while the next instruction is fetched, it is a two cycle instruction. If the result is not
0 the program proceeds with the following instruction.
ACC ← [m] + 1
Skip if ACC=0
None
SNZ [m].i
Description
Operation
Affected flag(s)
Skip if bit i of Data Memory is not 0
If bit i of the specified Data Memory is not 0, the following instruction is skipped. As this
requires the insertion of a dummy instruction while the next instruction is fetched, it is a two cycle instruction. If the result is 0 the program proceeds with the following instruction.
Skip if [m].i ≠ 0
None
SUB A,[m]
Description
Operation
Affected flag(s)
Subtract Data Memory from ACC
The specified Data Memory is subtracted from the contents of the Accumulator. The result is stored in the Accumulator. Note that if the result of subtraction is negative, the C flag will be cleared to 0, otherwise if the result is positive or zero, the C flag will be set to 1.
ACC ← ACC − [m]
OV, Z, AC, C
Rev. 1.00
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HT45F3820
Ultrasonic Humidifier 8-Bit Flash MCU
SUBM A,[m]
Description
Operation
Affected flag(s)
Subtract Data Memory from ACC with result in Data Memory
The specified Data Memory is subtracted from the contents of the Accumulator. The result is stored in the Data Memory. Note that if the result of subtraction is negative, the C flag will be cleared to 0, otherwise if the result is positive or zero, the C flag will be set to 1.
[m] ← ACC − [m]
OV, Z, AC, C
SUB A,x
Description
Operation
Affected flag(s)
Subtract immediate data from ACC
The immediate data specified by the code is subtracted from the contents of the Accumulator. The result is stored in the Accumulator. Note that if the result of subtraction is negative, the C flag will be cleared to 0, otherwise if the result is positive or zero, the C flag will be set to 1.
ACC ← ACC − x
OV, Z, AC, C
SWAP [m]
Description
Operation
Affected flag(s)
Swap nibbles of Data Memory
The low-order and high-order nibbles of the specified Data Memory are interchanged.
[m].3~[m].0 ↔ [m].7~[m].4
None
SWAPA [m]
Description
Operation
Affected flag(s)
Swap nibbles of Data Memory with result in ACC
The low-order and high-order nibbles of the specified Data Memory are interchanged. The result is stored in the Accumulator. The contents of the Data Memory remain unchanged.
ACC.3~ACC.0 ← [m].7~[m].4
ACC.7~ACC.4 ← [m].3~[m].0
None
SZ [m]
Description
Operation
Affected flag(s)
Skip if Data Memory is 0
If the contents of the specified Data Memory is 0, the following instruction is skipped. As this requires the insertion of a dummy instruction while the next instruction is fetched, it is a two cycle instruction. If the result is not 0 the program proceeds with the following instruction.
Skip if [m]=0
None
SZA [m]
Description
Operation
Affected flag(s)
Skip if Data Memory is 0 with data movement to ACC
The contents of the specified Data Memory are copied to the Accumulator. If the value is zero, the following instruction is skipped. As this requires the insertion of a dummy instruction while the next instruction is fetched, it is a two cycle instruction. If the result is not 0 the program proceeds with the following instruction.
ACC ← [m]
Skip if [m]=0
None
SZ [m].i
Description
Operation
Affected flag(s)
Skip if bit i of Data Memory is 0
If bit i of the specified Data Memory is 0, the following instruction is skipped. As this requires
the insertion of a dummy instruction while the next instruction is fetched, it is a two cycle
instruction. If the result is not 0, the program proceeds with the following instruction.
Skip if [m].i=0
None
Rev. 1.00
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May 30, 2016
HT45F3820
Ultrasonic Humidifier 8-Bit Flash MCU
TABRD [m]
Description
Operation
Affected flag(s)
Read table (specific page) to TBLH and Data Memory
The low byte of the program code (specific page) addressed by the table pointer pair (TBHP and TBLP) is moved to the specified Data Memory and the high byte moved to TBLH.
[m] ← program code (low byte)
TBLH ← program code (high byte)
None
TABRDC [m]
Description
Operation
Affected flag(s)
Read table (current page) to TBLH and Data Memory
The low byte of the program code (current page) addressed by the table pointer (TBLP) is moved to the specified Data Memory and the high byte moved to TBLH.
[m] ← program code (low byte)
TBLH ← program code (high byte)
None
TABRDL [m]
Description
Operation
Affected flag(s)
Read table (last page) to TBLH and Data Memory
The low byte of the program code (last page) addressed by the table pointer (TBLP) is moved to the specified Data Memory and the high byte moved to TBLH.
[m] ← program code (low byte)
TBLH ← program code (high byte)
None
XOR A,[m]
Description
Operation
Affected flag(s)
Logical XOR Data Memory to ACC
Data in the Accumulator and the specified Data Memory perform a bitwise logical XOR operation. The result is stored in the Accumulator.
ACC ← ACC ″XOR″ [m]
Z
XORM A,[m]
Description
Operation
Affected flag(s)
Logical XOR ACC to Data Memory
Data in the specified Data Memory and the Accumulator perform a bitwise logical XOR operation. The result is stored in the Data Memory.
[m] ← ACC ″XOR″ [m]
Z
XOR A,x
Description
Operation
Affected flag(s)
Logical XOR immediate data to ACC
Data in the Accumulator and the specified immediate data perform a bitwise logical XOR operation. The result is stored in the Accumulator.
ACC ← ACC ″XOR″ x
Z
Rev. 1.00
117
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HT45F3820
Ultrasonic Humidifier 8-Bit Flash MCU
Package Information
Note that the package information provided here is for consultation purposes only. As this
information may be updated at regular intervals users are reminded to consult the Holtek website for
the latest version of the Package/Carton Information.
Additional supplementary information with regard to packaging is listed below. Click on the relevant
section to be transferred to the relevant website page.
• Package Information (include Outline Dimensions, Product Tape and Reel Specifications)
• The Operation Instruction of Packing Materials
• Carton information
Rev. 1.00
118
May 30, 2016
HT45F3820
Ultrasonic Humidifier 8-Bit Flash MCU
8-pin SOP (150mil) Outline Dimensions
Symbol
Dimensions in inch
Min.
Nom.
Max.
A
—
0.236 BSC
—
B
—
0.154 BSC
—
0.020
C
0.012
—
C’
—
0.193 BSC
—
D
—
—
0.069
E
—
0.050 BSC
—
F
0.004
—
0.010
G
0.016
—
0.050
H
0.004
—
0.010
α
0°
—
8°
Symbol
A
Rev. 1.00
Dimensions in mm
Min.
Nom.
Max.
—
6.00 BSC
—
B
—
3.90 BSC
—
C
0.31
—
0.51
C’
—
4.90 BSC
—
D
—
—
1.75
E
—
1.27 BSC
—
F
0.10
—
0.25
G
0.40
—
1.27
H
0.10
—
0.25
α
0°
—
8°
119
May 30, 2016
HT45F3820
Ultrasonic Humidifier 8-Bit Flash MCU
10-pin SOP (150mil) Outline Dimensions
Symbol
Dimensions in inch
Min.
Nom.
Max.
A
—
0.236 BSC
—
B
—
0.154 BSC
—
C
0.012
—
0.018
C′
—
0.193 BSC
—
D
—
—
0.069
E
—
0.039 BSC
—
F
0.004
—
0.010
G
0.016
—
0.050
H
0.004
—
0.010
α
0°
—
8°
Symbol
Rev. 1.00
Dimensions in mm
Min.
Nom.
Max.
—
A
—
6.00 BSC
B
—
3.90 BSC
—
C
0.30
—
0.45
C′
—
4.90 BSC
—
D
—
—
1.75
E
—
1.00 BSC
—
F
0.10
—
0.25
G
0.40
—
1.27
H
0.10
—
0.25
α
0°
—
8°
120
May 30, 2016
HT45F3820
Ultrasonic Humidifier 8-Bit Flash MCU
Copyright© 2016 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. 1.00
121
May 30, 2016