Holtek BS87C16A-3 Touch a/d flash mcu with ocvp Datasheet

Touch A/D Flash MCU with OCVP
BS87B12A-3/BS87C16A-3/BS87D20A-3
Revision: V1.20
Date: �����������������
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
Table of Contents
Features............................................................................................................. 7
CPU Features.......................................................................................................................... 7
Peripheral Features.................................................................................................................. 7
General Description.......................................................................................... 8
Selection Table.................................................................................................. 8
Block Diagram................................................................................................... 9
Pin Assignment................................................................................................. 9
Pin Descriptions............................................................................................. 13
Absolute Maximum Ratings........................................................................... 22
D.C. Characteristics........................................................................................ 23
Operating Voltage Characteristics.......................................................................................... 23
Standby Current Characteristics............................................................................................ 23
Operating Current Characteristics.......................................................................................... 24
A.C. Characteristics........................................................................................ 25
High Speed Internal Oscillator – HIRC – Frequency Accuracy.............................................. 25
Low Speed Oscillators Characteristics – LIRC & LXT *......................................................... 25
Operating Frequency Characteristic Curves.......................................................................... 26
System Start Up Time Characteristics................................................................................... 26
Input/Output Characteristics......................................................................... 27
Memory Characteristics................................................................................. 27
LVD/LVR Electrical Characteristics............................................................... 28
A/D Converter Characteristics....................................................................... 28
Reference Voltage Characteristics................................................................ 28
Touch Key Electrical Characteristics............................................................ 29
OCVP Electrical Characteristics.................................................................... 31
Software Controlled LCD Electrical Characteristics................................... 31
I2C Characteristics.......................................................................................... 32
Power-on Reset Characteristics.................................................................... 32
System Architecture....................................................................................... 33
Clocking and Pipelining.......................................................................................................... 33
Program Counter.................................................................................................................... 34
Stack...................................................................................................................................... 34
Arithmetic and Logic Unit – ALU............................................................................................ 35
Flash Program Memory.................................................................................. 36
Structure................................................................................................................................. 36
Special Vectors...................................................................................................................... 36
Look-up Table......................................................................................................................... 37
Table Program Example......................................................................................................... 37
Rev. 1.20
2
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
In Circuit Programming – ICP................................................................................................ 38
On-Chip Debug Support – OCDS.......................................................................................... 39
Data Memory................................................................................................... 40
Structure................................................................................................................................. 40
Data Memory Addressing....................................................................................................... 41
General Purpose Data Memory............................................................................................. 41
Special Purpose Data Memory.............................................................................................. 41
Special Function Register Description......................................................... 45
Indirect Addressing Registers – IAR0, IAR1, IAR2................................................................ 45
Memory Pointers – MP0, MP1H/MP1L, MP2H/MP2L............................................................ 45
Accumulator – ACC................................................................................................................ 46
Program Counter Low Register – PCL................................................................................... 47
Look-up Table Registers – TBLP, TBHP, TBLH...................................................................... 47
Status Register – STATUS..................................................................................................... 47
EEPROM Data Memory................................................................................... 49
EEPROM Data Memory Structure......................................................................................... 49
EEPROM Registers............................................................................................................... 49
Reading Data from the EEPROM.......................................................................................... 51
Writing Data to the EEPROM................................................................................................. 51
Write Protection...................................................................................................................... 51
EEPROM Interrupt................................................................................................................. 51
Programming Considerations................................................................................................. 52
Oscillators....................................................................................................... 53
Oscillator Overview................................................................................................................ 53
System Clock Configurations................................................................................................. 53
Internal High Speed RC Oscillator – HIRC............................................................................ 54
Internal 32kHz Oscillator – LIRC............................................................................................ 54
External 32.768 kHz Crystal Oscillator – LXT – for BS87C16A-3/BS87D20A-3.................... 55
Operating Modes and System Clocks.......................................................... 57
System Clocks....................................................................................................................... 57
System Operation Modes....................................................................................................... 58
Control Registers................................................................................................................... 59
Operating Mode Switching..................................................................................................... 61
Standby Current Considerations............................................................................................ 64
Wake-up................................................................................................................................. 65
Programming Considerations................................................................................................. 65
Watchdog Timer.............................................................................................. 66
Watchdog Timer Clock Source............................................................................................... 66
Watchdog Timer Control Register.......................................................................................... 66
Watchdog Timer Operation.................................................................................................... 67
Reset and Initialisation................................................................................... 68
Reset Functions..................................................................................................................... 68
Reset Initial Conditions.......................................................................................................... 71
Rev. 1.20
3
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
Input/Output Ports.......................................................................................... 76
Pull-high Resistors................................................................................................................. 77
Port A Wake-up...................................................................................................................... 78
I/O Port Control Registers...................................................................................................... 78
I/O Port Source Current Selection.......................................................................................... 79
Pin-remapping Function – BS87B12A-3 only......................................................................... 81
I/O Pin Structures................................................................................................................... 82
Programming Considerations................................................................................................. 82
Timer Modules – TM....................................................................................... 83
Introduction............................................................................................................................ 83
TM Operation......................................................................................................................... 83
TM Clock Source.................................................................................................................... 84
TM Interrupts.......................................................................................................................... 84
TM External Pins.................................................................................................................... 84
TM Input/Output Pin Control Register.................................................................................... 85
Programming Considerations................................................................................................. 88
Compact Type TM – CTM0, CTM1................................................................. 89
Compact Type TM Operation................................................................................................. 89
Compact Type TM Register Description................................................................................ 90
Compact Type TM Operation Modes..................................................................................... 94
Periodic Type TM – PTM............................................................................... 100
Periodic TM Operation......................................................................................................... 100
Periodic Type TM Register Description................................................................................ 101
Periodic Type TM Operation Modes..................................................................................... 105
Analog to Digital Converter..........................................................................114
A/D Overview........................................................................................................................114
Registers Descriptions..........................................................................................................115
A/D Converter Reference Voltage.........................................................................................118
A/D Converter Input Signals..................................................................................................118
A/D Converter Operation.......................................................................................................119
Conversion Rate and Timing Diagram................................................................................. 120
Summary of A/D Conversion Steps...................................................................................... 121
Programming Considerations............................................................................................... 122
A/D Transfer Function.......................................................................................................... 122
A/D Programming Examples................................................................................................ 123
Touch Key Function..................................................................................... 125
Touch Key Structure............................................................................................................. 125
Touch Key Register Definition.............................................................................................. 126
Touch Key Operation............................................................................................................ 131
Touch Key Interrupt.............................................................................................................. 132
Programming Considerations............................................................................................... 132
Serial Interface Module – SIM...................................................................... 133
SPI Interface........................................................................................................................ 133
I2C Interface......................................................................................................................... 139
Rev. 1.20
4
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
UART Interface.............................................................................................. 149
UART External Pins............................................................................................................. 149
UART Data Transfer Scheme.............................................................................................. 150
UART Status and Control Registers.................................................................................... 150
Baud Rate Generator........................................................................................................... 155
UART Setup and Control..................................................................................................... 156
UART Transmitter................................................................................................................ 157
UART Receiver.................................................................................................................... 159
Managing Receiver Errors................................................................................................... 160
UART Interrupt Structure..................................................................................................... 161
UART Power Down and Wake-up........................................................................................ 163
Over Current/Voltage Protection Function – OCVP................................... 164
OCVP Operation.................................................................................................................. 164
OCVP Control Registers...................................................................................................... 165
Input Voltage Range............................................................................................................. 169
Input Offset Cancellation...................................................................................................... 170
OCVP Interrupt..................................................................................................................... 171
Programming Considerations............................................................................................... 171
Software Controlled LCD Driver.................................................................. 172
LCD Operation..................................................................................................................... 172
LCD Control Registers......................................................................................................... 174
Low Voltage Detector – LVD........................................................................ 177
LVD Register........................................................................................................................ 177
LVD Operation...................................................................................................................... 178
Interrupts....................................................................................................... 179
Interrupt Registers................................................................................................................ 179
Interrupt Operation............................................................................................................... 185
External Interrupt.................................................................................................................. 189
Touch Key Module Interrupt................................................................................................. 189
OCVP Interrupt..................................................................................................................... 189
TM Interrupts........................................................................................................................ 189
Multi-function Interrupt – BS87C16A-3 & BS87D20A-3....................................................... 190
Serial Interface Module Interrupt.......................................................................................... 190
EEPROM Interrupt............................................................................................................... 191
UART Transfer Interrupt....................................................................................................... 191
LVD Interrupt........................................................................................................................ 191
A/D Converter Interrupt........................................................................................................ 191
Time Base Interrupts............................................................................................................ 192
Interrupt Wake-up Function.................................................................................................. 193
Programming Considerations............................................................................................... 194
Configuration Options.................................................................................. 195
Application Circuits...................................................................................... 196
Rev. 1.20
5
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
Instruction Set............................................................................................... 197
Introduction.......................................................................................................................... 197
Instruction Timing................................................................................................................. 197
Moving and Transferring Data.............................................................................................. 197
Arithmetic Operations........................................................................................................... 197
Logical and Rotate Operation.............................................................................................. 198
Branches and Control Transfer............................................................................................ 198
Bit Operations...................................................................................................................... 198
Table Read Operations........................................................................................................ 198
Other Operations.................................................................................................................. 198
Instruction Set Summary............................................................................. 199
Table Conventions................................................................................................................ 199
Extended Instruction Set...................................................................................................... 201
Instruction Definition.................................................................................... 203
Extended Instruction Definition............................................................................................ 212
Package Information.................................................................................... 219
20-pin NSOP (150mil) Outline Dimensions.......................................................................... 220
24-pin SOP (300mil) Outline Dimensions............................................................................ 221
28-pin SOP (300mil) Outline Dimensions............................................................................ 222
44-pin LQFP (10mm×10mm) (FP2.0mm) Outline Dimensions............................................ 223
Rev. 1.20
6
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
Features
CPU Features
• Operating Voltage:
♦♦
fSYS=8MHz: 2.7V~5.5V
♦♦
fSYS=12MHz: 2.7V~5.5V
♦♦
fSYS=16MHz: 4.5V~5.5V
• Up to 0.25μs instruction cycle with 16MHz system clock at VDD=5V
• Power down and wake-up functions to reduce power consumption
• Oscillator Type:
♦♦
Internal High Speed RC – HIRC
♦♦
Internal 32kHz RC – LIRC
♦♦
External 32.768kHz Crystal – LXT for BS87C16A-3 & BS87D20A-3 only
• Fully integrated internal 8/12/16 MHz oscillator requires no external components
• Multi-mode operation: FAST, SLOW, IDLE and SLEEP
• All instructions executed in one to three instruction cycles
• Table read instructions
• 115 powerful instructions
• Up to 8-level subroutine nesting
• Bit manipulation instruction
Peripheral Features
• Program Memory: Up to 8K × 16
• Data Memory: Up to 768 × 8
• True EEPROM Memory: 64 × 8
• Up to 20 touch key functions – fully integrated without requiring external components
• Watchdog Timer function
• Up to 42 bidirectional I/O lines
• Programming I/O source current
• Up to 4SCOM & 36SSEG lines Software controlled LCD driver with 1/3 bias
• One external interrupt lines shared with I/O pins
• Multiple Timer Modules for time measure, input capture, compare match output, PWM output
function or single pulse output function
• Dual Time-Base functions for generation of fixed time interrupt signals
• Multi-channel 12-bit resolution A/D converter
• Over Current/Voltage Protection – OCVP
• Serial Interfaces Module – SIM for SPI or I2C
• Fully-duplex Universal Asynchronous Receiver and Transmitter Interface – UART
• Low voltage reset function
• Low voltage detect function
• Wide range of package types
Rev. 1.20
7
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
General Description
The series of devices is the Flash Memory type 8-bit high performance RISC architecture
microcontroller with fully integrated touch key functions. With all touch key functions provided
internally and with the convenience of Flash Memory multi-programming features, this series of
devices has all the features to offer designers a reliable and easy means of implementing touch
switches within their product applications.
The touch key functions are fully integrated thus completely eliminating the need for external
components. In addition to the Flash Program Memory, other memory includes an area of RAM Data
Memory as well as an area of true EEPROM Memory for storage of non-volatile data such as serial
numbers, calibration data etc. Analog features include a multi-channel 12-bit A/D converter and a
Over Current/Voltage Protection module. Protective features such as an internal Watchdog Timer,
Low Voltage Reset and Low Voltage Detector functions coupled with excellent noise immunity and
ESD protection ensure that reliable operation is maintained in hostile electrical environments.
A full choice of internal, external high and low speed oscillators are provided including fully
integrated system oscillators which require no external components for its implementation. The
ability to operate and switch dynamically between a range of operating modes using different
clock sources gives users the ability to optimise microcontroller operation and minimise power
consumption. Easy communication with the outside world is provided using the fully integrated SPI
or I2C interface functions, while the inclusion of flexible I/O programming features, Timer Modules
and many other features further enhance device functionality and flexibility.
A UART module is contained within this series of devices. This interface can support applications
such as data communication networks between microcontrollers, low-cost data links between PCs
and peripheral devices, portable and battery operated device communication, etc.
The touch key devices will find excellent use in a huge range of modern Touch Key product applications
such as instrumentation, household appliances, electronically controlled tools to name but a few.
Selection Table
Most features are common to all devices. The main features distinguishing them are Memory
capacity, I/O count, Time Module number, SSEG lines and touch key number. The following table
summarises the main features of each device.
Part No.
Program
Data
Memory Memory
Data
EEPROM
I/O
External
Interrupt
A/D
Timer Module
BS87B12A-3
3k × 16
384 × 8
64 × 8
22
1
12-bit × 8
BS87C16A-3
4k × 16
512 × 8
64 × 8
30
1
12-bit × 8
BS87D20A-3
8k × 16
768 × 8
64 × 8
42
1
10-bit CTM × 1
10-bit PTM × 1
10-bit CTM × 1
10-bit PTM × 2
10-bit CTM × 2
12-bit × 8
10-bit PTM × 2
Part No.
Time
Base
SCOM/
SSEG
Touch
Key
UART
SIM
Stacks
Package
BS87B12A-3
2
4/16
12
1
√
6
20NSOP
24SOP
BS87C16A-3
2
4/20
16
1
√
6
24/28SOP
44LQFP
BS87D20A-3
2
4/36
20
1
√
8
28SOP
44LQFP
Note: As devices exist in more than one package format, the table reflects the situation for the
package with the most pins.
Rev. 1.20
8
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
Block Diagram
Flash/EEPROM
P�og�a��ing Ci��uit�y
(ICP/OCDS)
EEPROM
Data
Me�o�y
Flash
P�og�a�
Me�o�y
Wat�hdog
Ti�e�
Reset
Ci��uit
Low
Voltage
Dete�t
Low
Voltage
Reset
RAM Data
Me�o�y
Ti�e
Base
Inte��upt
Cont�olle�
8-�it
RISC
MCU
Co�e
* Exte�nal
LXT Os�.
Inte�nal
HIRC/LIRC
Os�illato�s
12-�it A/D
Conve�te�
OCVP
(Co�pa�ato�+OPA)
I/O
Ti�e�
Modules
SIM
(SPI/I2C)
SCOM/S
SEG
UART
Tou�h Keys
*: The LXT oscillator is only available for the BS87C16A-3 and BS87D20A-3 devices.
Pin Assignment
PB0/SSEG0/KEY1
1
20
PA3/SDI/SDA/RX
PB1/SSEG1/KEY2
2
19
PA0/SDO/PTCK0/SCOM2/ICPDA/OCDSDA
PB2/SSEG2/KEY3
3
18
PA2/SCS/PTP0I/SCOM3/ICPCK/OCDSCK
PB3/SSEG3/KEY4
4
17
PA7/SCK/SCL/TX/OCVPVR
PB4/SSEG4/KEY�
�
1�
VDD
PB�/SSEG�/KEY�
�
1�
VSS
PC0/SSEG8/KEY9/AN0/VREF
7
14
PA1/SCOM0/OCVPCOUT
PC1/SSEG9/KEY10/AN1
8
13
PA4/INT/CTCK0/SCOM1/OCVPAO
PC2/[CTP0B]/SSEG10/KEY11/AN2/[OCVPAI1]
9
12
PC�/PTP0/SSEG13/AN�/OCVPAI0
10
11
PC4/PTP0B/SSEG12/AN4/OCVPCI
PC3/[CTP0]/SSEG11/KEY12/AN3/[OCVPAI2]
BS87B12A-3/BS87BV12A
20 NSOP-A
PB0/SSEG0/KEY1
1
24
PA3/SDI/SDA/RX
PB1/SSEG1/KEY2
2
23
PA0/SDO/PTCK0/SCOM2/ICPDA/OCDSDA
PB2/SSEG2/KEY3
3
22
PA2/SCS/PTP0I/SCOM3/ICPCK/OCDSCK
PB3/SSEG3/KEY4
4
21
PA7/SCK/SCL/TX/OCVPVR
PB4/SSEG4/KEY�
�
20
VDD
PB�/SSEG�/KEY�
�
19
VSS
PB�/SSEG�/KEY7
7
18
PA1/SCOM0/OCVPCOUT
PB7/SSEG7/KEY8
8
17
PA4/INT/CTCK0/SCOM1/OCVPAO
PC0/SSEG8/KEY9/AN0/VREF
9
1�
PC7/CTP0/SSEG1�/AN7/OCVPAI2
PC1/SSEG9/KEY10/AN1
10
1�
PC�/CTP0B/SSEG14/AN�/OCVPAI1
PC2/[CTP0B]/SSEG10/KEY11/AN2/[OCVPAI1]
11
14
PC�/PTP0/SSEG13/AN�/OCVPAI0
PC3/[CTP0]/SSEG11/KEY12/AN3/[OCVPAI2]
12
13
PC4/PTP0B/SSEG12/AN4/OCVPCI
BS87B12A-3/BS87BV12A
24 SOP-A
Rev. 1.20
9
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
PB0/SSEG0/KEY1
1
24
PA3/SDI/SDA/RX
PB1/SSEG1/KEY2
2
23
PA0/SDO/PTCK0/SCOM2/ICPDA/OCDSDA
PB2/SSEG2/KEY3
3
22
PA2/SCS/PTP0I/SCOM3/ICPCK/OCDSCK
PB3/SSEG3/KEY4
4
21
PA7/SCK/SCL/TX/OCVPVR
PB4/SSEG4/KEY�
�
20
VDD
PB�/PTCK1/SSEG�/KEY�
�
19
VSS
PB�/PTP1/SSEG�/KEY7
7
18
PA1/SCOM0/OCVPCOUT
PB7/PTP1I/SSEG7/KEY8
8
17
PA4/INT/CTCK0/SCOM1/OCVPAO
PC0/SSEG8/KEY9/AN0/VREF
9
1�
PC7/CTP0/SSEG1�/KEY1�/AN7/OCVPAI2
PC1/SSEG9/KEY10/AN1
10
1�
PC�/CTP0B/SSEG14/KEY1�/AN�/OCVPAI1
PC2/SSEG10/KEY11/AN2
11
14
PC�/PTP0/SSEG13/KEY14/AN�/OCVPAI0
PC3/SSEG11/KEY12/AN3
12
13
PC4/PTP0B/SSEG12/KEY13/AN4/OCVPCI
BS87C16A-3/BS87CV16A
24 SOP-A
PB0/SSEG0/KEY1
1
28
PB1/SSEG1/KEY2
2
27
PA0/SDO/PTCK0/SCOM2/ICPDA/OCDSDA
PB2/SSEG2/KEY3
3
2�
PA2/SCS/PTP0I/SCOM3/ICPCK/OCDSCK
PB3/SSEG3/KEY4
4
2�
PA7/SCK/SCL/TX/OCVPVR
PB4/SSEG4/KEY�
�
24
VDD
PB�/PTCK1/SSEG�/KEY�
�
23
PD1/SSEG17/XT2
PB�/PTP1/SSEG�/KEY7
7
22
PD0/SSEG1�/XT1
PB7/PTP1I/SSEG7/KEY8
8
21
VSS
PD3/PTP1B/SSEG19
9
20
PA1/SCOM0/OCVPCOUT
PD2/SSEG18
10
19
PA4/INT/CTCK0/SCOM1/OCVPAO
PC0/SSEG8/KEY9/AN0/VREF
11
18
PC7/CTP0/SSEG1�/KEY1�/AN7/OCVPAI2
PC1/SSEG9/KEY10/AN1
12
17
PC�/CTP0B/SSEG14/KEY1�/AN�/OCVPAI1
PC2/SSEG10/KEY11/AN2
13
1�
PC�/PTP0/SSEG13/KEY14/AN�/OCVPAI0
PC3/SSEG11/KEY12/AN3
14
1�
PC4/PTP0B/SSEG12/KEY13/AN4/OCVPCI
PA3/SDI/SDA/RX
BS87C16A-3/BS87CV16A
28 SOP-A
Rev. 1.20
10
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
PA2/SCS/PTP0I/SCOM3/ICPCK/OCDSCK
NC
NC
PA0/SDO/PTCK0/SCOM2/ICPDA/OCDSDA
PA3/SDI/SDA/RX
NC
NC
NC
PB0/SSEG0/KEY1
PB1/SSEG1/KEY2
PB2/SSEG2/KEY3
PB3/SSEG3/KEY4
PB4/SSEG4/KEY�
PB�/PTCK1/SSEG�/KEY�
PB�/PTP1/SSEG�/KEY7
PB7/PTP1I/SSEG7/KEY8
NC
PD�
PD4
PD3/PTP1B/SSEG19
PD2/SSEG18
PC0/SSEG8/KEY9/AN0/VREF
44 43 42 41 40 39 38 37 3� 3� 34
1
33
2
32
3
31
4
30
�
29
BS87C16A-3/BS87CV16A
�
28
44 LQFP-A
7
27
8
2�
9
2�
10
24
11
23
12 13 14 1� 1� 17 18 19 20 21 22
PA7/SCK/SCL/TX/OCVPVR
VDD
PD1/SSEG17/XT2
PD0/SSEG1�/XT1
VSS
NC
PD7
PD�
PA1/SCOM0/OCVPCOUT
PA4/INT/CTCK0/SCOM1/OCVPAO
PC7/CTP0/SSEG1�/KEY1�/AN7/OCVPAI2
PC�/CTP0B/SSEG14/KEY1�/AN�/OCVPAI1
NC
NC
NC
PC�/PTP0/SSEG13/KEY14/AN�/OCVPAI0
PC4/PTP0B/SSEG12/KEY13/AN4/OCVPCI
PC3/SSEG11/KEY12/AN3
PC2/SSEG10/KEY11/AN2
NC
NC
PC1/SSEG9/KEY10/AN1
PB0/SSEG0/KEY1
1
28
PA3/SDI/SDA/RX
PB1/SSEG1/KEY2
2
27
PA0/SDO/PTCK0/SCOM2/ICPDA/OCDSDA
PB2/SSEG2/KEY3
3
2�
PA2/SCS/PTP0I/SCOM3/ICPCK/OCDSCK
PB3/SSEG3/KEY4
4
2�
PA7/SCK/SCL/TX/OCVPVR
PB4/SSEG4/KEY�
�
24
VDD
PB�/PTCK1/SSEG�/KEY�
�
23
PD1/SSEG17/XT2
PB�/PTP1/SSEG�/KEY7
7
22
PD0/SSEG1�/XT1
PB7/PTP1I/SSEG7/KEY8
8
21
VSS
PD3/PTP1B/SSEG19/KEY9
9
20
PA1/SCOM0/KEY20/OCVPCOUT
PD2/SSEG18/KEY10
10
19
PA4/INT/CTCK0/SCOM1/KEY19/OCVPAO
PC0/SSEG8/KEY11/AN0/VREF
11
18
PC7/CTP0/SSEG1�/KEY18/AN7/OCVPAI2
PC1/SSEG9/KEY12/AN1
12
17
PC�/CTP0B/SSEG14/KEY17/AN�/OCVPAI1
PC2/SSEG10/KEY13/AN2
13
1�
PC�/PTP0/SSEG13/KEY1�/AN�/OCVPAI0
PC3/SSEG11/KEY14/AN3
14
1�
PC4/PTP0B/SSEG12/KEY1�/AN4/OCVPCI
BS87D20A-3/BS87DV20A
28 SOP-A
Rev. 1.20
11
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
PA2/SCS/PTP0I/SCOM3/ICPCK/OCDSCK
PE0/SSEG24
PE1/SSEG2�
PA0/SDO/PTCK0/SCOM2/ICPDA/OCDSDA
PA3/SDI/SDA/RX
PF0/CTCK1/SSEG32
PE2/SSEG2�
PE3/SSEG27
PB0/SSEG0/KEY1
PB1/SSEG1/KEY2
PB2/SSEG2/KEY3
PB3/SSEG3/KEY4
PB4/SSEG4/KEY�
PB�/PTCK1/SSEG�/KEY�
PB�/PTP1/SSEG�/KEY7
PB7/PTP1I/SSEG7/KEY8
PF1/CTP1/SSEG33
PD�/SSEG21
PD4/SSEG20
PD3/PTP1B/SSEG19/KEY9
PD2/SSEG18/KEY10
PC0/SSEG8/KEY11/AN0/VREF
44 43 42 41 40 39 38 37 3� 3� 34
1
33
2
32
3
31
4
30
�
29
BS87D20A-3/BS87DV20A
�
28
44 LQFP-A
7
27
8
2�
9
2�
10
24
11
23
12 13 14 1� 1� 17 18 19 20 21 22
PA7/SCK/SCL/TX/OCVPVR
VDD
PD1/SSEG17/XT2
PD0/SSEG1�/XT1
VSS
PF3/SSEG3�
PD7/SSEG23
PD�/SSEG22
PA1/SCOM0/KEY20/OCVPCOUT
PA4/INT/CTCK0/SCOM1/KEY19/OCVPAO
PC7/CTP0/SSEG1�/KEY18/AN7/OCVPAI2
PC�/CTP0B/SSEG14/KEY17/AN�/OCVPAI1
PE7/SSEG31
PE�/SSEG30
PF2/CTP1B/SSEG34
PC�/PTP0/SSEG13/KEY1�/AN�/OCVPAI0
PC4/PTP0B/SSEG12/KEY1�/AN4/OCVPCI
PC3/SSEG11/KEY14/AN3
PC2/SSEG10/KEY13/AN2
PE�/SSEG29
PE4/SSEG28
PC1/SSEG9/KEY12/AN1
Note: 1. If the pin-shared pin functions have multiple outputs simultaneously, its pin name at the right side of the
"/" sign can be used for higher priority.
2. The OCDSDA and OCDSCK pins are the OCDS dedicated pins and only available for the BS87BV12A/
BS87CV16A/BS87DV20A device which is the OCDS EV chip for the BS87B12A-3/BS87C16A-3/
BS87D20A-3 device.
Rev. 1.20
12
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
Pin Descriptions
With the exception of the power pins, all pins on these devices can be referenced 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 the Analog to Digital Converter, 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.
As the Pin Description table shows the situation for the package with the most pins, not all pins in
the table will be available on small package sizes.
BS87B12A-3
Pad Name
PA0/SDO/PTCK0/
SCOM2/ICPDA/
OCDSDA
PA1/SCOM0/
OCVPCOUT
PA2/SCS/PTP0I/
SCOM3/ICPCK/
OCDSCK
PA3/SDI/SDA/RX
PA4/INT/CTCK0/
SCOM1/
OCVPAO
PA7/SCK/SCL/TX/
OCVPVR
Rev. 1.20
Function
OPT
I/T
O/T
Description
PA0
PAWU
PAPU
ST
CMOS
General purpose I/O. Register enabled pull-up
and wake-up.
CMOS SPI data output
SDO
SIMC0
—
PTCK0
PTM0C0
ST
SCOM2
SLCDC0
—
SCOM Software LCD COM output
ICPDA
—
ST
CMOS ICP Data/Address pin
OCDSDA
—
ST
CMOS OCDS Data/Address pin, for EV chip only.
PA1
PAWU
PAPU
ST
CMOS
—
PTM0 clock input
General purpose I/O. Register enabled pull-up
and wake-up.
SCOM0
SLCDC0
—
SCOM Software LCD COM output
OCVPCOUT
OCVPC3
—
CMOS OCVP comparator output
PA2
PAWU
PAPU
ST
CMOS
SCS
SIMC0
ST
CMOS SPI slave select
PTP0I
PTM0C0
PTM0C1
ST
SCOM3
SLCDC0
—
SCOM Software LCD COM output
ICPCK
—
ST
CMOS ICP Clock pin
OCDSCK
—
ST
—
PA3
PAWU
PAPU
ST
CMOS
SDI
SIMC0
ST
SDA
SIMC0
ST
RX
UCR1
ST
—
PA4
PAWU
PAPU
ST
CMOS
INT
INTEG
INTC0
ST
—
External Interrupt
—
CTM0 clock input
—
—
General purpose I/O. Register enabled pull-up
and wake-up.
PTM0 capture input
OCDS Clock pin, for EV chip only.
General purpose I/O. Register enabled pull-up
and wake-up.
SPI data input
NMOS I2C data line
CTCK0
CTM0C0
ST
SCOM1
SLCDC0
—
OCVPAO
OCVPC3
—
AN
PA7
PAWU
PAPU
ST
CMOS
UART RX serial data input
General purpose I/O. Register enabled pull-up
and wake-up.
SCOM Software LCD COM output
OCVP OPA output
General purpose I/O. Register enabled pull-up
and wake-up.
SCK
SIMC0
ST
CMOS SPI serial clock
SCL
SIMC0
ST
NMOS I2C clock line
CMOS UART TX serial data output
TX
UCR1
—
OCVPVR
OCVPC1
AN
13
—
OCVP DAC reference voltage input
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
Pad Name
PB0/SSEG0/KEY1
PB1/SSEG1/KEY2
PB2/SSEG2/KEY3
PB3/SSEG3/KEY4
PB4/SSEG4/KEY5
PB5/SSEG5/KEY6
PB6/SSEG6/KEY7
PB7/SSEG7/KEY8
PC0/SSEG8/KEY9/
AN0/VREF
PC1/SSEG9/KEY10/
AN1
PC2/[CTP0B]/
SSEG10/KEY11/
AN2/[OCVPAI1]
PC3/[CTP0]/SSEG11/
KEY12/AN3/
[OCVPAI2]
Rev. 1.20
Function
OPT
I/T
PB0
PBPU
ST
CMOS General purpose I/O. Register enabled pull-up.
CMOS Software LCD SEG output
SSEG0
SLCDC1
—
KEY1
TKM0C1
NSI
O/T
—
Description
Touch key input
PB1
PBPU
ST
CMOS General purpose I/O. Register enabled pull-up.
SSEG1
SLCDC1
—
CMOS Software LCD SEG output
KEY2
TKM0C1
NSI
PB2
PBPU
ST
CMOS General purpose I/O. Register enabled pull-up.
CMOS Software LCD SEG output
—
Touch key input
SSEG2
SLCDC1
—
KEY3
TKM0C1
NSI
PB3
PBPU
ST
CMOS General purpose I/O. Register enabled pull-up.
CMOS Software LCD SEG output
—
Touch key input
SSEG3
SLCDC1
—
KEY4
TKM0C1
NSI
PB4
PBPU
ST
CMOS General purpose I/O. Register enabled pull-up.
CMOS Software LCD SEG output
—
Touch key input
SSEG4
SLCDC1
—
KEY5
TKM1C1
NSI
PB5
PBPU
ST
CMOS General purpose I/O. Register enabled pull-up.
SSEG5
SLCDC1
—
CMOS Software LCD SEG output
KEY6
TKM1C1
NSI
—
—
Touch key input
Touch key input
PB6
PBPU
ST
CMOS General purpose I/O. Register enabled pull-up.
SSEG6
SLCDC1
—
CMOS Software LCD SEG output
KEY7
TKM1C1
NSI
PB7
PBPU
ST
CMOS General purpose I/O. Register enabled pull-up.
CMOS Software LCD SEG output
—
Touch key input
SSEG7
SLCDC1
—
KEY8
TKM1C1
NSI
PC0
PCPU
ST
CMOS General purpose I/O. Register enabled pull-up.
CMOS Software LCD SEG output
—
Touch key input
SSEG8
SLCDC2
—
KEY9
TKM2C1
NSI
—
Touch key input
AN0
ACERL
AN
—
A/D Converter analog input
VREF
TMPC0
AN
—
A/D Converter reference voltage input
PC1
PCPU
ST
CMOS General purpose I/O. Register enabled pull-up.
CMOS Software LCD SEG output
SSEG9
SLCDC2
—
KEY10
TKM2C1
NSI
—
Touch key input
AN1
ACERL
AN
—
A/D Converter analog input
PC2
PCPU
ST
CMOS General purpose I/O. Register enabled pull-up.
[CTP0B]
TMPC0
IFS
—
CMOS CTM0 inverted output
SSEG10
SLCDC2
—
CMOS Software LCD SEG output
KEY11
TKM2C1
NSI
—
Touch key input
AN2
ACERL
AN
—
A/D Converter analog input
[OCVPAI1]
OCVPC3
IFS
AN
—
OCVP OCP input signal 1
PC3
PCPU
ST
CMOS General purpose I/O. Register enabled pull-up.
[CTP0]
TMPC0
IFS
—
CMOS CTM0 non-inverted output
CMOS Software LCD SEG output
SSEG11
SLCDC2
—
KEY12
TKM2C1
NSI
—
Touch key input
AN3
ACERL
AN
—
A/D Converter analog input
[OCVPAI2]
OCVPC3
IFS
AN
—
OCVP OCP input signal 2
14
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
Pad Name
PC4/PTP0B/SSEG12/
AN4/OCVPCI
PC5/PTP0/SSEG13/
AN5/OCVPAI0
PC6/CTP0B/SSEG14/
AN6/OCVPAI1
PC7/CTP0/SSEG15/
AN7/OCVPAI2
Function
OPT
I/T
PC4
PCPU
ST
CMOS General purpose I/O. Register enabled pull-up.
O/T
Description
PTP0B
TMPC0
—
CMOS PTM0 inverted output
SSEG12
SLCDC2
—
CMOS Software LCD SEG output
AN4
ACERL
AN
—
A/D Converter analog input
OCVPCI
OCVPC3
AN
—
OCVP OCP input signal / Comparator noninverting input signal
PC5
PCPU
ST
CMOS General purpose I/O. Register enabled pull-up.
PTP0
TMPC0
—
CMOS PTM0 non-inverted output
SSEG13
SLCDC2
—
CMOS Software LCD SEG output
AN5
ACERL
AN
—
A/D Converter analog input
OCVPAI0
OCVPC3
AN
—
OCVP OCP input signal 0
PC6
PCPU
ST
CMOS General purpose I/O. Register enabled pull-up.
CTP0B
TMPC0
IFS
—
CMOS CTM0 inverted output
SSEG14
SLCDC2
—
CMOS Software LCD SEG output
AN6
ACERL
AN
—
A/D Converter analog input
OCVPAI1
OCVPC3
IFS
AN
—
OCVP OCP input signal 1
PC7
PCPU
ST
CMOS General purpose I/O. Register enabled pull-up.
CTP0
TMPC0
IFS
—
CMOS CTM0 non-inverted output
SSEG15
SLCDC2
—
CMOS Software LCD SEG output
AN7
ACERL
AN
—
A/D Converter analog input
OCVPAI2
OCVPC3
IFS
AN
—
OCVP OCP input signal 2
VDD
VDD
—
PWR
—
Positive power supply
VSS
VSS
—
PWR
—
Negative power supply, ground.
Legend: I/T: Input type;
CMOS: CMOS output;
ST: Schmitt Trigger input;
PWR: Power
Rev. 1.20
O/T: Output type;
NMOS: NMOS output;
AN: Analog signal;
15
OPT: Optional by register selection;
SCOM: SCOM output;
NSI: Non-standard input;
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
BS87C16A-3
Pad Name
PA0/SDO/PTCK0/
SCOM2/ICPDA/
OCDSDA
PA1/SCOM0/
OCVPCOUT
PA2/SCS/PTP0I/
SCOM3/ICPCK/
OCDSCK
PA3/SDI/SDA/RX
PA4/INT/CTCK0/
SCOM1/OCVPAO
PA7/SCK/SCL/TX/
OCVPVR
PB0/SSEG0/KEY1
PB1/SSEG1/KEY2
PB2/SSEG2/KEY3
PB3/SSEG3/KEY4
Rev. 1.20
Function
OPT
PA0
PAWU
PAPU
I/T
O/T
Description
ST
General purpose I/O. Register enabled pull-up
CMOS
and wake-up.
CMOS SPI data output
SDO
SIMC0
—
PTCK0
PTM0C0
ST
SCOM2
SLCDC0
—
—
PTM0 clock input
SCOM Software LCD COM output
ICPDA
—
ST
CMOS ICP Data/Address pin
OCDSDA
—
ST
CMOS OCDS Data/Address pin, for EV chip only.
PA1
PAWU
PAPU
ST
CMOS
General purpose I/O. Register enabled pull-up
and wake-up.
SCOM0
SLCDC0
—
SCOM Software LCD COM output
OCVPCOUT
OCVPC3
—
CMOS OCVP comparator output
PA2
PAWU
PAPU
ST
CMOS
SCS
SIMC0
ST
CMOS SPI slave select
PTP0I
PTM0C0
PTM0C1
ST
SCOM3
SLCDC0
—
SCOM Software LCD COM output
ICPCK
—
ST
CMOS ICP Clock pin
OCDSCK
—
ST
—
PA3
PAWU
PAPU
ST
CMOS
SDI
SIMC0
ST
SDA
SIMC0
ST
RX
UCR1
ST
—
PA4
PAWU
PAPU
ST
CMOS
INT
INTEG
INTC0
ST
—
External Interrupt
—
CTM0 clock input
—
—
General purpose I/O. Register enabled pull-up
and wake-up.
PTM0 capture input
OCDS Clock pin, for EV chip only.
General purpose I/O. Register enabled pull-up
and wake-up.
SPI data input
NMOS I2C data line
UART RX serial data input
General purpose I/O. Register enabled pull-up
and wake-up.
CTCK0
CTM0C0
ST
SCOM1
SLCDC0
—
OCVPAO
OCVPC3
—
PA7
PAWU
PAPU
ST
General purpose I/O. Register enabled pull-up
CMOS
and wake-up.
SCK
SIMC0
ST
CMOS SPI serial clock
SCL
SIMC0
ST
NMOS I2C clock line
CMOS UART TX serial data output
SCOM Software LCD COM output
AN
TX
UCR1
—
OCVPVR
OCVPC1
AN
—
OCVP OPA output
OCVP DAC reference voltage input
PB0
PBPU
ST
CMOS General purpose I/O. Register enabled pull-up.
SSEG0
SLCDC1
—
CMOS Software LCD SEG output
KEY1
TKM0C1
NSI
PB1
PBPU
ST
CMOS General purpose I/O. Register enabled pull-up.
SSEG1
SLCDC1
—
CMOS Software LCD SEG output
KEY2
TKM0C1
NSI
PB2
PBPU
ST
CMOS General purpose I/O. Register enabled pull-up.
SSEG2
SLCDC1
—
CMOS Software LCD SEG output
KEY3
TKM0C1
NSI
PB3
PBPU
ST
CMOS General purpose I/O. Register enabled pull-up.
SSEG3
SLCDC1
—
CMOS Software LCD SEG output
KEY4
TKM0C1
NSI
16
—
—
—
—
Touch key input
Touch key input
Touch key input
Touch key input
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
Pad Name
PB4/SSEG4/KEY5
PB5/PTCK1/SSEG5/
KEY6
PB6/PTP1/SSEG6/
KEY7
PB7/PTP1I/SSEG7/
KEY8
PC0/SSEG8/KEY9/
AN0/VREF
PC1/SSEG9/KEY10/
AN1
PC2/SSEG10/KEY11/
AN2
PC3/SSEG11/KEY12/
AN3
PC4/PTP0B/SSEG12/
KEY13/AN4/OCVPCI
PC5/PTP0/SSEG13/
KEY14/AN5/OCVPAI0
Rev. 1.20
Function
OPT
I/T
PB4
PBPU
ST
CMOS General purpose I/O. Register enabled pull-up.
O/T
SSEG4
SLCDC1
—
CMOS Software LCD SEG output
KEY5
TKM1C1
NSI
—
Description
Touch key input
PB5
PBPU
ST
PTCK1
PTM1C0
ST
CMOS General purpose I/O. Register enabled pull-up.
SSEG5
SLCDC1
—
KEY6
TKM1C1
NSI
PB6
PBPU
ST
CMOS General purpose I/O. Register enabled pull-up.
—
PTM1 clock input
CMOS Software LCD SEG output
—
Touch key input
PTP1
TMPC0
—
CMOS PTM1 non-inverted output
SSEG6
SLCDC1
—
CMOS Software LCD SEG output
KEY7
TKM1C1
NSI
PB7
PBPU
ST
PTP1I
PTM1C0
PTM1C1
ST
SSEG7
SLCDC1
—
KEY8
TKM1C1
NSI
—
Touch key input
CMOS General purpose I/O. Register enabled pull-up.
—
PTM1 capture input
CMOS Software LCD SEG output
—
Touch key input
PC0
PCPU
ST
CMOS General purpose I/O. Register enabled pull-up.
SSEG8
SLCDC2
—
CMOS Software LCD SEG output
KEY9
TKM2C1
NSI
—
Touch key input
AN0
ACERL
AN
—
A/D Converter analog input
VREF
TMPC0
AN
—
A/D Converter reference voltage input
PC1
PCPU
ST
CMOS General purpose I/O. Register enabled pull-up.
SSEG9
SLCDC2
—
CMOS Software LCD SEG output
KEY10
TKM2C1
NSI
—
Touch key input
AN1
ACERL
AN
—
A/D Converter analog input
PC2
PCPU
ST
CMOS General purpose I/O. Register enabled pull-up.
SSEG10
SLCDC2
—
CMOS Software LCD SEG output
KEY11
TKM2C1
NSI
—
Touch key input
AN2
ACERL
AN
—
A/D Converter analog input
PC3
PCPU
ST
CMOS General purpose I/O. Register enabled pull-up.
SSEG11
SLCDC2
—
CMOS Software LCD SEG output
KEY12
TKM2C1
NSI
—
Touch key input
AN3
ACERL
AN
—
A/D Converter analog input
PC4
PCPU
ST
CMOS General purpose I/O. Register enabled pull-up.
PTP0B
TMPC0
—
CMOS PTM0 inverted output
SSEG12
SLCDC2
—
CMOS Software LCD SEG output
KEY13
TKM3C1
NSI
—
Touch key input
AN4
ACERL
AN
—
A/D Converter analog input
OCVPCI
OCVPC3
AN
—
OCVP OCP input signal / Comparator noninverting input signal
PC5
PCPU
ST
CMOS General purpose I/O. Register enabled pull-up.
PTP0
TMPC0
—
CMOS PTM0 non-inverted output
SSEG13
SLCDC2
—
CMOS Software LCD SEG output
KEY14
TKM3C1
NSI
—
Touch key input
AN5
ACERL
AN
—
A/D Converter analog input
OCVPAI0
OCVPC3
AN
—
OCVP OCP input signal 0
17
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
Pad Name
PC6/CTP0B/SSEG14/
KEY15/AN6/OCVPAI1
PC7/CTP0/SSEG15/
KEY16/AN7/OCVPAI2
PD0/SEG16/XT1
PD1/SEG17/XT2
PD2/SEG18
PD3/PTP1B/SEG19
Function
OPT
I/T
PC6
PCPU
ST
CMOS General purpose I/O. Register enabled pull-up.
O/T
Description
CTP0B
TMPC0
—
CMOS CTM0 inverted output
SSEG14
SLCDC2
—
CMOS Software LCD SEG output
KEY15
TKM3C1
NSI
—
Touch key input
AN6
ACERL
AN
—
A/D Converter analog input
OCVPAI1
OCVPC3
AN
—
OCVP OCP input signal 1
PC7
PCPU
ST
CMOS General purpose I/O. Register enabled pull-up.
CTP0
TMPC0
—
CMOS CTM0 non-inverted output
SSEG15
SLCDC2
—
CMOS Software LCD SEG output
KEY16
TKM3C1
NSI
—
Touch key input
AN7
ACERL
AN
—
A/D Converter analog input
OCVPAI2
OCVPC3
AN
—
OCVP OCP input signal 2
PD0
PDPU
ST
CMOS General purpose I/O. Register enabled pull-up.
SSEG16
SLCDC3
—
CMOS Software LCD SEG output
XT1
CO
LXT
PD1
PDPU
ST
CMOS General purpose I/O. Register enabled pull-up.
SSEG17
SLCDC3
—
CMOS Software LCD SEG output
XT2
CO
—
PD2
PDPU
ST
CMOS General purpose I/O. Register enabled pull-up.
SSEG18
SLCDC3
—
CMOS Software LCD SEG output
—
LXT
LXT pin
LXT pin
PD3
PDPU
ST
CMOS General purpose I/O. Register enabled pull-up.
PTP1B
TMPC0
—
CMOS PTM1 inverted output
SSEG19
SLCDC3
—
CMOS Software LCD SEG output
PD4~PD7
PDPU
ST
CMOS General purpose I/O. Register enabled pull-up.
VDD
VDD
—
PWR
—
Positive power supply
VSS
VSS
—
PWR
—
Negative power supply, ground.
PD4~PD7
Legend: I/T: Input type;
O/T: Output type;
OPT: Optional by configuration option (CO) or register selection;
CMOS: CMOS output;
NMOS: NMOS output;
SCOM: SCOM output;
ST: Schmitt Trigger input;
AN: Analog signal;
NSI: Non-standard input;
PWR: Power;
LXT: Low frequency crystal oscillator
Rev. 1.20
18
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
BS87D20A-3
Pad Name
PA0/SDO/PTCK0/
SCOM2/ICPDA/
OCDSDA
PA1/SCOM0/KEY20/
OCVPCOUT
PA2/SCS/PTP0I/
SCOM3/ICPCK/
OCDSCK
PA3/SDI/SDA/RX
PA4/INT/CTCK0/
SCOM1/KEY19
OCVPAO
PA7/SCK/SCL/TX/
OCVPVR
PB0/SSEG0/KEY1
PB1/SSEG1/KEY2
PB2/SSEG2/KEY3
Rev. 1.20
Function
OPT
PA0
PAWU
PAPU
I/T
O/T
Description
ST
General purpose I/O. Register enabled pull-up
CMOS
and wake-up.
CMOS SPI data output
SDO
SIMC0
—
PTCK0
PTM0C0
ST
SCOM2
SLCDC0
—
—
PTM0 clock input
SCOM Software LCD COM output
ICPDA
—
ST
CMOS ICP Data/Address pin
OCDSDA
—
ST
CMOS OCDS Data/Address pin, for EV chip only.
PA1
PAWU
PAPU
ST
CMOS
SCOM0
SLCDC0
—
SCOM Software LCD COM output
KEY20
TKM4C1
NSI
OCVPCOUT
OCVPC3
—
CMOS OCVP comparator output
PA2
PAWU
PAPU
ST
CMOS
SCS
SIMC0
ST
CMOS SPI slave select
PTP0I
PTM0C0
PTM0C1
ST
SCOM3
SLCDC0
—
SCOM Software LCD COM output
ICPCK
—
ST
CMOS ICP Clock pin
OCDSCK
—
ST
—
PA3
PAWU
PAPU
ST
CMOS
SDI
SIMC0
ST
SDA
SIMC0
ST
RX
UCR1
ST
—
PA4
PAWU
PAPU
ST
CMOS
INT
INTEG
INTC0
ST
—
External Interrupt
—
CTM0 clock input
—
—
—
General purpose I/O. Register enabled pull-up
and wake-up.
Touch key input
General purpose I/O. Register enabled pull-up
and wake-up.
PTM0 capture input
OCDS Clock pin, for EV chip only.
General purpose I/O. Register enabled pull-up
and wake-up.
SPI data input
NMOS I2C data line
UART RX serial data input
General purpose I/O. Register enabled pull-up
and wake-up.
CTCK0
CTM0C0
ST
SCOM1
SLCDC0
—
KEY19
TKM4C1
NSI
—
Touch key input
OCVPAO
OCVPC3
—
AN
OCVP OPA output
PA7
PAWU
PAPU
ST
CMOS
SCOM Software LCD COM output
General purpose I/O. Register enabled pull-up
and wake-up.
SCK
SIMC0
ST
CMOS SPI serial clock
SCL
SIMC0
ST
NMOS I2C clock line
CMOS UART TX serial data output
TX
UCR1
—
OCVPVR
OCVPC1
AN
PB0
PBPU
ST
CMOS General purpose I/O. Register enabled pull-up.
CMOS Software LCD SEG output
—
OCVP DAC reference voltage input
SSEG0
SLCDC1
—
KEY1
TKM0C1
NSI
PB1
PBPU
ST
CMOS General purpose I/O. Register enabled pull-up.
CMOS Software LCD SEG output
SSEG1
SLCDC1
—
KEY2
TKM0C1
NSI
—
—
Touch key input
Touch key input
PB2
PBPU
ST
CMOS General purpose I/O. Register enabled pull-up.
SSEG2
SLCDC1
—
CMOS Software LCD SEG output
KEY3
TKM0C1
NSI
—
19
Touch key input
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
Pad Name
PB3/SSEG3/KEY4
PB4/SSEG4/KEY5
PB5/PTCK1/SSEG5/
KEY6
PB6/PTP1/SSEG6/
KEY7
PB7/PTP1I/SSEG7/
KEY8
PC0/SSEG8/KEY11/
AN0/VREF
PC1/SSEG9/KEY12/
AN1
PC2/SSEG10/
KEY13/AN2
PC3/SSEG11/KEY14/
AN3
PC4/PTP0B/
SSEG12/KEY15/
AN4/OCVPCI
PC5/PTP0/SSEG13/
KEY16/AN5/
OCVPAI0
Rev. 1.20
Function
OPT
I/T
PB3
PBPU
ST
CMOS General purpose I/O. Register enabled pull-up.
CMOS Software LCD SEG output
SSEG3
SLCDC1
—
KEY4
TKM0C1
NSI
O/T
—
Description
Touch key input
PB4
PBPU
ST
CMOS General purpose I/O. Register enabled pull-up.
SSEG4
SLCDC1
—
CMOS Software LCD SEG output
KEY5
TKM1C1
NSI
PB5
PBPU
ST
PTCK1
PTM1C0
ST
SSEG5
SLCDC1
—
KEY6
TKM1C1
NSI
—
Touch key input
CMOS General purpose I/O. Register enabled pull-up.
—
PTM1 clock input
CMOS Software LCD SEG output
—
Touch key input
PB6
PBPU
ST
CMOS General purpose I/O. Register enabled pull-up.
PTP1
TMPC
—
CMOS PTM1 non-inverted output
SSEG6
SLCDC1
—
CMOS Software LCD SEG output
KEY7
TKM1C1
NSI
PB7
PBPU
ST
PTP1I
PTM1C0
PTM1C1
ST
—
Touch key input
CMOS General purpose I/O. Register enabled pull-up.
—
PTM1 capture input
SSEG7
SLCDC1
—
KEY8
TKM1C1
NSI
CMOS Software LCD SEG output
PC0
PCPU
ST
CMOS General purpose I/O. Register enabled pull-up.
CMOS Software LCD SEG output
—
Touch key input
SSEG8
SLCDC2
—
KEY11
TKM2C1
NSI
—
Touch key input
AN0
ACERL
AN
—
A/D Converter analog input
VREF
TMPC
AN
—
A/D Converter reference voltage input
PC1
PCPU
ST
CMOS General purpose I/O. Register enabled pull-up.
CMOS Software LCD SEG output
SSEG9
SLCDC2
—
KEY12
TKM2C1
NSI
—
Touch key input
AN1
ACERL
AN
—
A/D Converter analog input
PC2
PCPU
ST
CMOS General purpose I/O. Register enabled pull-up.
CMOS Software LCD SEG output
SSEG10
SLCDC2
—
KEY13
TKM3C1
NSI
AN2
ACERL
AN
PC3
PCPU
ST
CMOS General purpose I/O. Register enabled pull-up.
CMOS Software LCD SEG output
—
Touch key input
—
A/D Converter analog input
SSEG11
SLCDC2
—
KEY14
TKM3C1
NSI
—
Touch key input
AN3
ACERL
AN
—
A/D Converter analog input
PC4
PCPU
ST
CMOS General purpose I/O. Register enabled pull-up.
PTP0B
TMPC
—
CMOS PTM0 inverted output
SSEG12
SLCDC2
—
CMOS Software LCD SEG output
KEY15
TKM3C1
NSI
—
Touch key input
AN4
ACERL
AN
—
A/D Converter analog input
OCVPCI
OCVPC3
AN
—
OCVP OCP input signal / Comparator noninverting input signal
PC5
PCPU
ST
CMOS General purpose I/O. Register enabled pull-up.
PTP0
TMPC
—
CMOS PTM0 non-inverted output
SSEG13
SLCDC2
—
CMOS Software LCD SEG output
KEY16
TKM3C1
NSI
—
AN5
ACERL
AN
—
A/D Converter analog input
OCVPAI0
OCVPC3
AN
—
OCVP OCP input signal 0
20
Touch key input
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
Pad Name
PC6/CTP0B/
SSEG14/KEY17/
AN6/OCVPAI1
PC7/CTP0/SSEG15/
KEY18/AN7/
OCVPAI2
PD0/SEG16/XT1
PD1/SEG17/XT2
PD2/SEG18/KEY10
PD3/PTP1B/SEG19/
KEY9
PD4/SSEG20
PD5/SSEG21
PD6/SSEG22
PD7/SSEG23
PE0/SSEG24
PE1/SSEG25
PE2/SSEG26
PE3/SSEG27
PE4/SSEG28
PE5/SSEG29
PE6/SSEG30
Rev. 1.20
Function
OPT
I/T
PC6
PCPU
ST
CMOS General purpose I/O. Register enabled pull-up.
O/T
Description
CTP0B
TMPC
—
CMOS CTM0 inverted output
SSEG14
SLCDC2
—
CMOS Software LCD SEG output
KEY17
TKM4C1
NSI
—
AN6
ACERL
AN
—
A/D Converter analog input
OCVPAI1
OCVPC3
AN
—
OCVP OCP input signal 1
Touch key input
PC7
PCPU
ST
CMOS General purpose I/O. Register enabled pull-up.
CTP0
TMPC
—
CMOS CTM0 non-inverted output
SSEG15
SLCDC2
—
CMOS Software LCD SEG output
KEY18
TKM4C1
NSI
—
Touch key input
AN7
ACERL
AN
—
A/D Converter analog input
OCVPAI2
OCVPC3
AN
—
OCVP OCP input signal 2
PD0
PDPU
ST
CMOS General purpose I/O. Register enabled pull-up.
SSEG16
SLCDC3
—
CMOS Software LCD SEG output
XT1
CO
LXT
PD1
PDPU
ST
CMOS General purpose I/O. Register enabled pull-up.
SSEG17
SLCDC3
—
CMOS Software LCD SEG output
XT2
CO
—
—
LXT
LXT pin
LXT pin
PD2
PDPU
ST
CMOS General purpose I/O. Register enabled pull-up.
SSEG18
SLCDC3
—
CMOS Software LCD SEG output
KEY10
TKM2C1
NSI
PD1
PDPU
ST
CMOS General purpose I/O. Register enabled pull-up.
—
Touch key input
PTP1B
TMPC
—
CMOS PTM1 inverted output
SSEG19
SLCDC3
—
CMOS Software LCD SEG output
KEY9
TKM2C1
NSI
—
Touch key input
CMOS General purpose I/O. Register enabled pull-up.
PD4
PDPU
ST
SSEG20
SLCDC3
—
CMOS Software LCD SEG output
PD5
PDPU
ST
CMOS General purpose I/O. Register enabled pull-up.
SSEG21
SLCDC3
—
CMOS Software LCD SEG output
PD6
PDPU
ST
CMOS General purpose I/O. Register enabled pull-up.
SSEG22
SLCDC3
—
CMOS Software LCD SEG output
PD7
PDPU
ST
CMOS General purpose I/O. Register enabled pull-up.
SSEG23
SLCDC3
—
CMOS Software LCD SEG output
CMOS General purpose I/O. Register enabled pull-up.
PE0
PEPU
ST
SSEG24
SLCDC4
—
CMOS Software LCD SEG output
PE1
PEPU
ST
CMOS General purpose I/O. Register enabled pull-up.
SSEG25
SLCDC4
—
CMOS Software LCD SEG output
PE2
PEPU
ST
CMOS General purpose I/O. Register enabled pull-up.
SSEG26
SLCDC4
—
CMOS Software LCD SEG output
PE3
PEPU
ST
CMOS General purpose I/O. Register enabled pull-up.
SSEG27
SLCDC4
—
CMOS Software LCD SEG output
PE4
PEPU
ST
CMOS General purpose I/O. Register enabled pull-up.
SSEG28
SLCDC4
—
CMOS Software LCD SEG output
PE5
PEPU
ST
CMOS General purpose I/O. Register enabled pull-up.
SSEG29
SLCDC4
—
CMOS Software LCD SEG output
PE6
PEPU
ST
CMOS General purpose I/O. Register enabled pull-up.
SSEG30
SLCDC4
—
CMOS Software LCD SEG output
21
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
Pad Name
PE7/SSEG31
PF0/CTCK1/SSEG32
PF1/CTP1/SSEG33
Function
OPT
I/T
PE7
PEPU
ST
O/T
Description
SSEG31
SLCDC4
—
CMOS Software LCD SEG output
PF0
PFPU
ST
CMOS General purpose I/O. Register enabled pull-up.
CTCK1
CTM1C0
ST
SSEG32
SLCDC5
—
CMOS Software LCD SEG output
CMOS General purpose I/O. Register enabled pull-up.
CMOS General purpose I/O. Register enabled pull-up.
—
CTM1 clock input
PF1
PFPU
ST
CTP1
TMPC1
ST
SSEG33
SLCDC5
—
CMOS Software LCD SEG output
CMOS General purpose I/O. Register enabled pull-up.
—
CTM1 non-inverted output
PF2
PFPU
ST
CTP1B
TMPC1
ST
SSEG34
SLCDC5
—
PF3
PFPU
ST
CMOS General purpose I/O. Register enabled pull-up.
SSEG35
SLCDC5
—
CMOS Software LCD SEG output
VDD
VDD
—
PWR
—
Positive power supply
VSS
VSS
—
PWR
—
Negative power supply, ground.
PF2/CTP1B/SSEG34
PF3/SSEG35
—
CTM1 inverted output
CMOS Software LCD SEG output
Legend: I/T: Input type;
O/T: Output type;
OPT: Optional by configuration option (CO) or register selection;
CMOS: CMOS output;
NMOS: NMOS output;
SCOM: SCOM output;
ST: Schmitt Trigger input;
AN: Analog signal;
NSI: Non-standard input;
PWR: Power;
LXT: Low frequency crystal oscillator
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.
Rev. 1.20
22
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
D.C. Characteristics
For data in the following tables, note that factors such as oscillator type, operating voltage, operating
frequency, pin load conditions, temperature and program instruction type, etc., can all exert an
influence on the measured values.
Operating Voltage Characteristics
Ta= -40°C to 85°C
Symbol
Parameter
Test Conditions
fSYS=8MHz
Operating Voltage – HIRC
Min.
Typ.
Max.
2.7
—
5.5
Unit
fSYS=12MHz
2.7
—
5.5
fSYS=16MHz
4.5
—
5.5
Operating Voltage – LXT
fSYS=32768Hz
2.7
—
5.5
V
Operating Voltage – LIRC
fSYS=32kHz
2.7
—
5.5
V
VDD
V
Standby Current Characteristics
Ta=25°C
Symbol
Standby Mode
SLEEP Mode
IDLE0 Mode – LIRC
Test Conditions
VDD
3V
5V
3V
5V
3V
IDLE0 Mode – LXT *
ISTB
5V
3V
5V
3V
5V
IDLE1 Mode – HIRC
3V
5V
5V
Conditions
WDT on
fSUB=fLIRC=on
fSUB=fLXT=on, LXTLP=1
fSUB=fLXT=on, LXTLP=0
fSUB on, fSYS=8MHz
fSUB on, fSYS=12MHz
fSUB on, fSYS=16MHz
Min.
Typ.
Max.
—
1.3
3.0
—
2.4
5.0
—
1.3
3.0
—
2.4
5.0
—
2.5
5.0
—
6
10
—
5
10
—
18
30
—
0.8
1.2
—
1.0
2.0
—
0.9
1.4
—
1.4
2.1
—
2.0
4.0
Unit μA
μA
μA
μA
mA
mA
mA
Notes: When using the characteristic table data, the following notes should be taken into consideration:
• Any digital inputs are setup in a non-floating condition.
• All measurements are taken under conditions of no load and with all peripherals in an off state.
• There are no DC current paths.
• All Standby Current values are taken after a HALT instruction execution thus stopping all instruction
execution.
• The LXT oscillator is only available for BS87C16A-3 and BS87D20A-3.
Rev. 1.20
23
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
Operating Current Characteristics
Ta=25°C
Symbol
Operating Mode
SLOW Mode – LIRC
Test Conditions
VDD
3V
5V
3V
SLOW Mode – LXT *
IDD
5V
3V
5V
3V
5V
FAST Mode – HIRC
3V
5V
5V
Conditions
fSYS=32kHz
fSYS=32768Hz, LXTLP=1
fSYS=32768Hz, LXTLP=0
fSYS=8MHz
fSYS=12MHz
fSYS=16MHz
Min.
Typ.
Max.
—
25
50
—
36
72
—
25
50
—
36
72
—
30
60
—
48
96
—
1.2
1.8
—
2.2
3.3
—
1.6
2.4
—
3.3
5.0
—
4.0
6.0
Unit
μA
μA
μA
mA
mA
mA
Notes: When using the characteristic table data, the following notes should be taken into consideration:
• Any digital inputs are setup in a non floating condition.
• All measurements are taken under conditions of no load and with all peripherals in an off state.
• There are no DC current paths.
• All Operating Current values are measured using a continuous NOP instruction program loop.
• The LXT oscillator is only available for BS87C16A-3 and BS87D20A-3.
Rev. 1.20
24
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
A.C. Characteristics
For data in the following tables, note that factors such as oscillator type, operating voltage, operating
frequency and temperature etc., can all exert an influence on the measured values.
High Speed Internal Oscillator – HIRC – Frequency Accuracy
During the program writing operation the writer will trim the HIRC oscillator at a user selected
HIRC frequency and user selected voltage of either 3V or 5V.
8/12/16 MHz
Symbol
Parameter
8 MHz Writer Trimmed
HIRC Frequency
12 MHz Writer Trimmed
HIRC Frequency
fHIRC
16 MHz Writer Trimmed
HIRC Frequency
Test Conditions
VDD
Temp.
3V/5V
2.7V~5.5V
3V/5V
2.7V~5.5V
5V
4.5V~5.5V
Min
Typ
Max
+1%
Unit
25°C
-1%
8
-40°C ~ 85°C
-2%
8
+2%
25°C
-2.5%
8
+2.5%
-40°C ~ 85°C
-3%
8
+3%
25°C
-1%
12
+1%
-40°C ~ 85°C
-2%
12
+2%
25°C
-2.5%
12
+2.5%
-40°C ~ 85°C
-3%
12
+3%
+1%
25°C
-1%
16
-40°C ~ 85°C
-2%
16
+2%
25°C
-2.5%
16
+2.5%
-40°C ~ 85°C
-3%
16
+3%
MHz
MHz
MHz
Notes: 1. The 3V/5V values for VDD are provided as these are the two selectable fixed voltages at which the
HIRC frequency is trimmed by the writer.
2. The row below the 3V/5V trim voltage row is provided to show the values for the full VDD range
operating voltage. It is recommended that the trim voltage is fixed at 3V for application voltage ranges
from 2.7V to 3.6V and fixed at 5V for application voltage ranges from 3.3V to 5.5V.
3. The minimum and maximum tolerance values provided in the table are only for the frequency at which
the writer trims the HIRC oscillator. After trimming at this chosen specific frequency any change in
HIRC oscillator frequency using the oscillator register control bits by the application program will give
a frequency tolerance to within ±20%.
Low Speed Oscillators Characteristics – LIRC & LXT *
Ta=25°C
Symbol
Parameter
Test Conditions
VDD
Temp.
Min.
Typ.
Max.
Unit
fLIRC
LIRC Oscillator Frequency
5V
25°C
-10%
32
+10%
kHz
fLXT
LXT Oscillator Frequency
—
—
—
32.768
—
kHz
*: The LXT oscillator is only available for BS87C16A-3 and BS87D20A-3.
Rev. 1.20
25
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
Operating Frequency Characteristic Curves
System Operating Frequency
16MHz
12MHz
8MHz
~
~
~
~
~
~
2.7V
4.5V
5.5V
Operating Voltage
System Start Up Time Characteristics
Ta= -40°C ~ 85°C
Symbol
tSST
tRSTD
tSRESET
Parameter
Test Conditions
Min.
Typ.
Max.
Unit
fSYS=fH ~ fH/64, fH=fHIRC
—
16
—
tHIRC
fSYS=fSUB=fLIRC
—
2
—
tLIRC
fSYS=fSUB=*fLXT
—
128
—
tLXT
fSYS=fH ~ fH/64, fH=fHIRC
—
2
—
tH
fSYS=fSUB=fLIRC or *fLXT
—
2
—
tSUB
—
fHIRC switches from off → on
—
16
—
tHIRC
—
*fLXT switches from off → on
—
128
—
tLXT
System Reset Delay Time
Reset Source from Power-on Reset
or LVR Hardware Reset
—
RRPOR=5V/ms
25
50
100
System Reset Delay Time
LVRC/WDTC Software Reset
—
—
System Reset Delay Time
Reset Source from WDT Overflow
—
—
8.3
16.7
33.3
Minimum Software Reset Width to
Reset
—
—
45
90
120
VDD
Conditions
System Start-up Time
Wake-up from Condition where fSYS
is off
—
—
—
System Start-up Time
Wake-up from Condition where fSYS
is on
—
—
System Speed Switch Time
FAST to Slow Mode or SLOW to
FAST Mode
ms
μs
Notes: 1. For the System Start-up time values, whether fSYS is on or off depends upon the mode type and the
chosen fSYS system oscillator. Details are provided in the System Operating Modes section.
2. The time units, shown by the symbols tHIRC etc. are the inverse of the corresponding frequency values as
provided in the frequency tables. For example tHIRC=1/fHIRC, tSYS=1/fSYS etc.
3. If the LIRC is used as the system clock and if it is off when in the SLEEP Mode, then an additional
LIRC start up time, tSTART, as provided in the LIRC frequency table, must be added to the tSST time in the
table above.
4. The System Speed Switch Time is effectively the time taken for the newly activated oscillator to start up.
5. The LXT oscillator is only available for BS87C16A-3 and BS87D20A-3.
Rev. 1.20
26
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
Input/Output Characteristics
Ta=25°C
Symbol
Test Conditions
Parameter
VDD
Conditions
Min.
Typ.
Max.
VIL
Input Low Voltage for I/O Ports or Input
Pins
5V
—
0
—
1.5
—
—
0
—
0.2VDD
VIH
Input High Voltage for I/O Ports or Input
Pins
5V
—
3.5
—
5.0
—
—
0.8VDD
—
VDD
IOL
Sink Current for I/O Pins
16
32
—
32
64
—
VOH=0.9VDD, PxPS=00,
x=A, B, C, D, E or F
-1.0
-2.0
—
-2.0
-4.0
—
VOH=0.9VDD, PxPS=01,
x=A, B, C, D, E or F
-1.75
-3.5
—
-3.5
-7.0
—
VOH=0.9VDD, PxPS=10,
x=A, B, C, D, E or F
-2.5
-5.0
—
-5.0
-10.0
—
VOH=0.9VDD, PxPS=11,
x=A, B, C, D, E or F
-5.5
-11.0
—
-11.0 -22.0
—
3V
5V
3V
5V
3V
IOH
5V
Source Current for I/O Pins
3V
5V
3V
5V
RPH
Pull-high Resistance for I/O Ports(Note)
VOL=0.1VDD
3V
—
20
60
100
5V
—
10
30
50
VIN=VDD or VIN=VSS
Unit
V
V
mA
mA
kΩ
ILEAK
Input leakage current
5V
—
—
±1
μA
tTPI
TM Capture Input Minimum Pulse Width
—
—
0.3
—
—
μs
tTCK
TM Clock Input Minimum Pulse Width
—
—
0.3
—
—
μs
tINT
Interrupt Input Pin Minimum Pulse Width
—
—
10
—
—
μs
Note: The RPH internal pull high resistance value is calculated by connecting to ground and enabling the input pin
with a pull-high resistor and then measuring the input sink current at the specified supply voltage level.
Dividing the voltage by this measured current provides the RPH value.
Memory Characteristics
Ta= -40°C~85°C
Symbol
VRW
Parameter
VDD for Read / Write
Test Conditions
Min.
Typ.
Max.
Unit
—
VDDmin
—
VDDmax
V
VDD
Conditions
—
Program Flash / Data EEPROM Memory
tDEW
Erase / Write cycle time
—
—
—
4
6
ms
IDDPGM
Programming / Erase current
on VDD
—
—
—
—
5.0
mA
EP
Cell Endurance
—
—
100K
—
—
E/W
tRETD
ROM Data Retention time
—
Ta=25°C
—
40
—
Year
—
Device in SLEEP Mode
1.0
—
—
V
RAM Data Memory
VDR
Rev. 1.20
RAM Data Retention voltage
27
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
LVD/LVR Electrical Characteristics
Ta=25°C
Symbol
VLVR
Parameter
Low Voltage Reset Voltage
Test Conditions
Min. Typ. Max. Unit
Conditions
VDD
— LVR enabled, voltage select 2.55V -5% 2.55 +5%
LVD enabled, voltage select 2.7V
VLVD
Low Voltage Detect Voltage
V
2.7
LVD enabled, voltage select 3.0V
3.0
— LVD enabled, voltage select 3.3V
-5% 3.3
LVD enabled, voltage select 3.6V
3.6
LVD enabled, voltage select 4.0V
4.0
+5%
V
15
μs
tLVDS
LVDO Stable Time
For LVR enable, VBGEN=0,
—
LVD off → on
tLVR
Minimum Low Voltage Width to Reset
—
—
120 240
480
μs
tLVD
Minimum Low Voltage Width to Interrupt —
—
60
240
μs
—
—
120
A/D Converter Characteristics
Ta=25°C
Symbol
Parameter
Test Conditions
VDD
Conditions
Min. Typ. Max. Unit
VDD
Operating Voltage
—
—
2.7
—
5.5
V
VADI
Input Voltage
—
—
0
—
VREF
V
VREF
Reference Voltage
—
—
2
—
VDD
V
VREF=VDD, tADCK=0.5μs or 10μs
—
—
±3
LSB
VREF=VDD, tADCK=0.5μs or 10μs
—
—
±4
LSB
3V
DNL
Differential Non-linearity
INL
Integral Non-linearity
IADC
Additional Current Consumption for A/D
Converter Enable
3V
tADCK
Clock Period
—
—
5V
3V
5V
5V
—
1
2
—
1.5
3
0.5
—
10
No load, tADCK =0.5μs
mA
μs
tON2ST
A/D Converter On-to-Start Time
—
—
4
—
—
μs
tADS
Sampling Time
—
—
—
4
—
tADCK
tADC
Conversion Time
(Including A/D Sample and Hold Time)
—
—
—
16
—
tADCK
Reference Voltage Characteristics
Ta=25°C
Symbol
Parameter
Test Conditions
VDD
Conditions
Min.
Typ.
Max.
Unit
VBG
Bandgap Reference Voltage
—
—
- 3%
1.09
+ 3%
V
IBG
Additional Current Consumption for
Bandgap Reference Voltage Enable
—
—
—
200
300
μA
tBG
VBG Turn-on Stable Time
—
—
—
—
200
μs
Note: The VBG voltage is used as the A/D converter internal signal input.
Rev. 1.20
28
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
Touch Key Electrical Characteristics
Ta=25°C
Touch Key RC Oscillator 500kHz mode selected
Symbol
Parameter
Only sensor (KEY) Oscillator
Operating Current
IKEYOSC
Test Conditions
VDD
3V
5V
3V
Only reference Oscillator
Operating Current
IREFOSC
5V
3V
5V
Conditions
*fSENOSC=500kHz
*fREFOSC=500kHz, MnTSS=0
*fREFOSC=500kHz, MnTSS=1
Min.
Typ.
Max.
—
30
60
—
60
120
—
30
60
—
60
120
—
30
60
—
60
120
Unit
μA
μA
μA
CKEYOSC
Sensor (KEY) Oscillator External
Capacitor
5V
*fSENOSC=500kHz
5
10
20
pF
CREFOSC
Reference Oscillator Internal
Capacitor
5V
*fREFOSC=500kHz
5
10
20
pF
fKEYOSC
Sensor (KEY) Oscillator Operating
Frequency
5V
*CEXT=7, 8, 9, 10, 11, 12, 13,
14, 15, … , 50pF
100
500
1000
kHz
fREFOSC
Reference Oscillator Operating
Frequency
5V
* CINT=7, 8, 9, 10, 11, 12, 13,
14, 15, … , 50pF
100
500
1000
kHz
Note: 1. fSENOSC=500kHz: Adjust KEYn external capacitor to make sure that the Sensor oscillator frequency is
equal to 500kHz.
2. fREFOSC=500kHz: Adjust Reference oscillator internal capacitor to make sure that the reference oscillator
frequency is equal to 500kHz.
Touch Key RC Oscillator 1000kHz mode selected
Symbol
Parameter
IKEYOSC
Only sensor (KEY) Oscillator
Operating Current
IREFOSC
Only reference Oscillator
Operating Current
Test Conditions
VDD
3V
5V
3V
5V
3V
5V
Conditions
*fSENOSC=1000kHz
*fREFOSC=1000kHz, MnTSS=0
*fREFOSC=1000kHz, MnTSS=1
Min.
Typ.
Max.
—
40
80
—
80
160
—
40
80
—
80
160
—
40
80
—
80
160
Unit
μA
μA
μA
CKEYOSC
Sensor (KEY) Oscillator External
Capacitor
5V
*fSENOSC=1000kHz
5
10
20
pF
CREFOSC
Reference Oscillator Internal
Capacitor
5V
*fREFOSC=1000kHz
5
10
20
pF
fKEYOSC
Sensor (KEY) Oscillator
Operating Frequency
5V
*CEXT=1, 2, 3, 4, 5, 6, 7, 8, 9, …
, 50pF
150
1000
2000
kHz
fREFOSC
Reference Oscillator Operating
Frequency
5V
* CINT=1, 2, 3, 4, 5, 6, 7, 8, 9,
… , 50pF
150
1000
2000
kHz
Note: 1. fSENOSC=1000kHz: Adjust KEYn external capacitor to make sure that the Sensor oscillator frequency is
equal to 1000kHz.
2. fREFOSC=1000kHz: Adjust Reference oscillator internal capacitor to make sure that the reference oscillator
frequency is equal to 1000kHz.
Rev. 1.20
29
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
Touch Key RC Oscillator 1500kHz mode selected
Symbol
Parameter
Only sensor (KEY) Oscillator
Operating Current
IKEYOSC
Test Conditions
VDD
3V
5V
3V
Only reference Oscillator
Operating Current
IREFOSC
5V
3V
5V
CKEYOSC
Sensor (KEY) Oscillator External
Capacitor
3V
CREFOSC
Reference Oscillator Internal
Capacitor
3V
fKEYOSC
Sensor (KEY) Oscillator
Operating Frequency
3V
fREFOSC
Reference Oscillator Operating
Frequency
3V
5V
5V
5V
5V
Conditions
*fSENOSC=1500kHz
*fREFOSC=1500kHz, MnTSS=0
*fREFOSC=1500kHz, MnTSS=1
*fSENOSC=1500kHz
*fREFOSC=1500kHz
Min.
Typ.
Max.
—
60
120
—
120
240
—
60
120
—
120
240
—
60
120
—
120
240
Unit
μA
μA
μA
4
8
16
pF
5
10
20
pF
4
8
16
pF
5
10
20
pF
*CEXT=1, 2, 3, 4, 5, 6, 7, 8, 9, … ,
50pF
150
1500
3000
kHz
150
1500
3000
kHz
* CINT=1, 2, 3, 4, 5, 6, 7, 8, 9, … ,
50pF
150
1500
3000
kHz
150
1500
3000
kHz
Note: 1. fSENOSC=1500kHz: Adjust KEYn external capacitor to make sure that the Sensor oscillator frequency is
equal to 1500kHz.
2. fREFOSC=1500kHz: Adjust Reference oscillator internal capacitor to make sure that the reference oscillator
frequency is equal to 1500kHz.
Touch Key RC Oscillator 2000kHz mode selected
Symbol
IKEYOSC
Parameter
Only sensor (KEY) Oscillator
Operating Current
Test Conditions
VDD
3V
5V
3V
IREFOSC
Only reference Oscillator
Operating Current
5V
3V
5V
CKEYOSC
Sensor (KEY) Oscillator External
Capacitor
3V
CREFOSC
Reference Oscillator Internal
Capacitor
3V
fKEYOSC
Sensor (KEY) Oscillator
Operating Frequency
3V
Reference Oscillator Operating
Frequency
3V
fREFOSC
5V
5V
5V
5V
Conditions
*fSENOSC=2000kHz
*fREFOSC=2000kHz, MnTSS=0
*fREFOSC=2000kHz, MnTSS=1
*fSENOSC=2000kHz
Min.
Typ.
Max.
—
80
160
—
160
320
—
80
160
—
160
320
—
80
160
—
160
320
Unit
μA
μA
μA
4
8
16
pF
5
10
20
pF
4
8
16
pF
5
10
20
pF
*CEXT=1, 2, 3, 4, 5, 6, 7, 8, 9, … ,
50pF
150
2000
4000
kHz
150
2000
4000
kHz
* CINT=1, 2, 3, 4, 5, 6, 7, 8, 9, … ,
50pF
150
2000
4000
kHz
150
2000
4000
kHz
*fREFOSC=2000kHz
Note: 1. fSENOSC=2000kHz: Adjust KEYn external capacitor to make sure that the Sensor oscillator frequency is
equal to 2000kHz.
2. fREFOSC=2000kHz: Adjust Reference oscillator internal capacitor to make sure that the reference oscillator
frequency is equal to 2000kHz.
Rev. 1.20
30
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
OCVP Electrical Characteristics
Ta=25°C
Symbol
Parameter
IOCVP
Additional Current Consumption for
OCVP Enable
VOS_CMP
Comparator Input Offset Voltage
VCM_CMP
Comparator Common Mode
Voltage Range
VOS_OPA
OPA Input Offset Voltage
Test Conditions
Typ.
Max.
—
—
1.25
—
0.73
1.25
-15
—
15
3V/5V With calibration
-4
—
4
3V/5V
VSS
—
VDD-1.4
-15
—
15
-4
—
4
VDD
Min.
Conditions
3V
DAC VREF=2.5V
5V
3V/5V
3V/5V
Without calibration,
OCVPCOF[4:0]=10000
—
Without calibration,
OCVPOOF[5:0]=100000
3V/5V With calibration
Unit
mA
mV
V
mV
VCM_OPA
OPA Common Mode Voltage Range 3V/5V
—
VSS
—
VDD-1.4
V
VHYS
Hysteresis
3V/5V
—
20
40
60
mV
VOR
OPA Maximum Output Voltage
Range
3V/5V
—
VSS+0.1
—
VDD-0.1
V
Ga
PGA Gain Accuracy (Note)
3V/5V
—
-5
—
5
%
VREF
DAC Reference Voltage
3V/5V OCVPVRS=1
2
—
VDD
V
—
—
±2
—
—
±1
—
—
±2
—
—
±1.5
DNL
Differential Non-linearity
INL
Integral Non-linearity
3V
5V
3V
5V
DAC VREF=VDD
DAC VREF=VDD
LSB
LSB
Note: The PGA gain accuracy is guaranteed only when the PGA output voltage meets the VOR specification.
Software Controlled LCD Electrical Characteristics
Ta=25°C
Symbol
IBIAS
Parameter
LCD bias current
Test Conditions
VDD
5V
Conditions
VSCOM
VSSEG
Rev. 1.20
LCD COM 2/3 Bias Level Output
LCD SEG 1/3 Bias Level Output
LCD SEG 2/3 Bias Level Output
Typ.
Max.
ISEL[1:0]=00
5.8
8.3
10.8
ISEL[1:0]=01
11.7
16.7
21.7
ISEL[1:0]=10
35
50
65
70
100
130
ISEL[1:0]=11
LCD COM 1/3 Bias Level Output
Min.
—
No load
—
No load
31
0.317VDD 0.333VDD 0.35VDD
0.634VDD 0.666VDD
0.7VDD
0.317VDD 0.333VDD 0.35VDD
0.634VDD 0.666VDD
0.7VDD
Unit
μA
V
V
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
I2C Characteristics
Ta=25°C
Symbol
Parameter
System Frequency for I2C Standard
Mode (100kHz)
Test Condition
VDD
Condition
—
fI2C
System Frequency for I2C Fast Mode
(400kHz)
—
Min. Typ. Max. Unit
No clock debounce
2
—
—
2 system clocks debounce
4
—
—
4 system clocks debounce
8
—
—
No clock debounce
5
—
—
2 system clocks debounce
10
—
—
4 system clocks debounce
20
—
—
MHz
MHz
Power-on Reset Characteristics
Ta=25°C
Symbol
Test Conditions
Parameter
VDD
Conditions
Min.
Typ. Max. Unit
VPOR
VDD Start Voltage to Ensure Power-on Reset
—
—
—
—
100
mV
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
RRPOR
VPOR
Ti�e
tPOR
Rev. 1.20
32
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
System Architecture
A key factor in the high-performance features of the Holtek range of microcontrollers is attributed
to their internal system architecture. The range of devices take advantage of the usual features found
within RISC microcontrollers providing increased speed of operation and enhanced performance.
The pipelining scheme is implemented in such a way that instruction fetching and instruction
execution are overlapped, hence instructions are effectively executed in one cycle, with the
exception of branch or call instructions. An 8-bit wide ALU is used in practically all instruction set
operations, which carries out arithmetic operations, logic operations, rotation, increment, decrement,
branch decisions, etc. The internal data path is simplified by moving data through the Accumulator
and the ALU. Certain internal registers are implemented in the Data Memory and can be directly
or indirectly addressed. The simple addressing methods of these registers along with additional
architectural features ensure that a minimum of external components is required to provide a
functional I/O and A/D control system with maximum reliability and flexibility. This makes these
devices suitable for low-cost, high-volume production for controller applications.
Clocking and Pipelining
The main system clock, derived from either a HIRC, LXT or LIRC oscillator is subdivided into
four internally generated non-overlapping clocks, T1~T4. Note that the LXT oscillator is only
available for the BS87C16A-3 and BS87D20A-3 devices. The Program Counter is incremented at
the beginning of the T1 clock during which time a new instruction is fetched. The remaining T2~T4
clocks carry out the decoding and execution functions. In this way, one T1~T4 clock cycle forms
one instruction cycle. Although the fetching and execution of instructions takes place in consecutive
instruction cycles, the pipelining structure of the microcontroller ensures that instructions are
effectively executed in one instruction cycle. The exception to this are instructions where the
contents of the Program Counter are changed, such as subroutine calls or jumps, in which case the
instruction will take one more instruction cycle to execute.
For instructions involving branches, such as jump or call instructions, two machine cycles are
required to complete instruction execution. An extra cycle is required as the program takes one
cycle to first obtain the actual jump or call address and then another cycle to actually execute the
branch. The requirement for this extra cycle should be taken into account by programmers in timing
sensitive applications.
fSYS
(System Clock)
Phase Clock T1
Phase Clock T2
Phase Clock T3
Phase Clock T4
Program Counter
Pipelining
PC
PC+1
Fetch Inst. (PC)
Execute Inst. (PC-1)
Fetch Inst. (PC+1)
Execute Inst. (PC)
PC+2
Fetch Inst. (PC+2)
Execute Inst. (PC+1)
System Clocking and Pipelining
Rev. 1.20
33
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
1
MOV A,[12H]
2
CALL DELAY
3
CPL [12H]
4
:
5
:
6 DELAY: NOP
Fetch Inst. 1
Execute Inst. 1
Fetch Inst. 2 Execute Inst. 2
Fetch Inst. 3
Flush Pipeline
Fetch Inst. 6
Execute Inst. 6
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
Device
High Byte
Low Byte (PCL)
BS87B12A-3
PC11~PC8
PC7~PC0
BS87C16A-3
PC11~PC8
PC7~PC0
BS87D20A-3
PC12~PC8
PC7~PC0
Program Counter
The lower byte of the Program Counter, known as the Program Counter Low register or PCL, is
available for program control and is a readable and writeable register. By transferring data directly
into this register, a short program jump can be executed directly; however, as only this low byte
is available for manipulation, the jumps are limited to the present page of memory that is 256
locations. When such program jumps are executed it should also be noted that a dummy cycle
will be inserted. Manipulating the PCL register may cause program branching, so an extra cycle is
needed to pre-fetch.
Stack
This is a special part of the memory which is used to save the contents of the Program Counter
only. The stack has multiple levels and is neither part of the data nor part of the program space,
and is neither readable nor writeable. The activated level is indexed by the Stack Pointer, and is
neither readable nor writeable. At a subroutine call or interrupt acknowledge signal, the contents of
the Program Counter are pushed onto the stack. At the end of a subroutine or an interrupt routine,
signaled by a return instruction, RET or RETI, the Program Counter is restored to its previous value
from the stack. After a device reset, the Stack Pointer will point to the top of the stack.
If the stack is full and an enabled interrupt takes place, the interrupt request flag will be recorded but
the acknowledge signal will be inhibited. When the Stack Pointer is decremented, by RET or RETI,
the interrupt will be serviced. This feature prevents stack overflow allowing the programmer to use
the structure more easily. However, when the stack is full, a CALL subroutine instruction can still
be executed which will result in a stack overflow. Precautions should be taken to avoid such cases
which might cause unpredictable program branching.
Rev. 1.20
34
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
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 2
Stack
Pointer
Stack Level 3
Bottom of Stack
Stack Level N
:
:
:
Program Memory
Note: N=6 for BS87B12A-3 & BS87C16A-3 while N=8 for BS87D20A-3.
Arithmetic and Logic Unit – ALU
The arithmetic-logic unit or ALU is a critical area of the microcontroller that carries out arithmetic
and logic operations of the instruction set. Connected to the main microcontroller data bus, the ALU
receives related instruction codes and performs the required arithmetic or logical operations after
which the result will be placed in the specified register. As these ALU calculation or operations may
result in carry, borrow or other status changes, the status register will be correspondingly updated to
reflect these changes. The ALU supports the following functions:
• Arithmetic operations:
ADD, ADDM, ADC, ADCM, SUB, SUBM, SBC, SBCM, DAA
LADD, LADDM, LADC, LADCM, LSUB, LSUBM, LSBC, LSBCM, LDAA
• Logic operations:
AND, OR, XOR, ANDM, ORM, XORM, CPL, CPLA
LAND, LOR, LXOR, LANDM, LORM, LXORM, LCPL, LCPLA
• Rotation:
RRA, RR, RRCA, RRC, RLA, RL, RLCA, RLC
LRRA, LRR, LRRCA, LRRC, LRLA, LRL, LRLCA, LRLC
• Increment and Decrement:
INCA, INC, DECA, DEC
LINCA, LINC, LDECA, LDEC
• Branch decision:
JMP, SZ, SZA, SNZ, SIZ, SDZ, SIZA, SDZA, CALL, RET, RETI
LSZ, LSZA, LSNZ, LSIZ, LSDZ, LSIZA, LSDZA
Rev. 1.20
35
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
Flash Program Memory
The Program Memory is the location where the user code or program is stored. For these devices
series the Program Memory are Flash type, which means it can be programmed and re-programmed
a large number of times, allowing the user the convenience of code modification on the same
device. By using the appropriate programming tools, these Flash devices offer users the flexibility to
conveniently debug and develop their applications while also offering a means of field programming
and updating.
Device
Capacity
BS87B12A-3
3K × 16
BS87C16A-3
4K × 16
BS87D20A-3
8K × 16
Structure
The Program Memory has a capacity of 3K×16 to 8K×16 bits. The Program Memory is addressed
by the Program Counter and also contains data, table information and interrupt entries. Table data,
which can be setup in any location within the Program Memory, is addressed by a separate table
pointer registers.
000H
BS87B12A-3
BS87C16A-3
BS87D20A-3
Initialisation Vector
Initialisation Vector
Initialisation Vector
Interrupt Vectors
Interrupt Vectors
Interrupt Vectors
Look-up Table
Look-up Table
Look-up Table
004H
03CH
n00H
nFFH
0BFFH
16 bits
0FFFH
16 bits
1FFFH
16 bits
Program Memory Structure
Special Vectors
Within the Program Memory, certain locations are reserved for the reset and interrupts. The location
000H is reserved for use by these devices reset for program initialisation. After a device reset is
initiated, the program will jump to this location and begin execution.
Rev. 1.20
36
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
Look-up Table
Any location within the Program Memory can be defined as a look-up table where programmers can
store fixed data. To use the look-up table, the table pointer must first be setup by placing the address
of the look up data to be retrieved in the table pointer register, TBLP and TBHP. These registers
define the total address of the look-up table.
After setting up the table pointer, the table data can be retrieved from the Program Memory using
the "TABRD [m]" or "TABRDL [m]" instructions respectively when the memory [m] is located in
sector 0. If the memory [m] is located in other sectors except sector 0, the data can be retrieved from
the program memory using the corresponding extended table read instruction such as "LTABRD [m]"
or "LTABRDL [m]" respectively. When the instruction is executed, the lower order table byte from
the Program Memory will be transferred to the user defined Data Memory register [m] as specified
in the instruction. The higher order table data byte from the Program Memory will be transferred to
the TBLH special register. 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.
Program Memory
Address
Last Page or
TBHP Register
TBLP Register
Data
16 bits
Register TBLH
User Selected
Register
High Byte
Low Byte
Table Program Example
The accompanying example shows how the table pointer and table data is defined and retrieved from
the device. This example uses raw table data located in the last page which is stored there using the
ORG statement. The value at this ORG statement is "1F00H" which refers to the start address of
the last page within the 8K Program Memory of the device. The table pointer low byte register is
setup here to have an initial value of "06H". This will ensure that the first data read from the data
table will be at the Program Memory address "1F06H" or 6 locations after the start of the last page.
Note that the value for the table pointer is referenced to the first address of the present page pointed
by the TBHP register 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/write register and can be restored, care should be taken
to ensure its protection if both the main routine and Interrupt Service Routine use table read
instructions. If using the table read instructions, the Interrupt Service Routines may change the
value of the TBLH and subsequently cause errors if used again by the main routine. As a rule it is
recommended that simultaneous use of the table read instructions should be avoided. However, in
situations where simultaneous use cannot be avoided, the interrupts should be disabled prior to the
execution of any main routine table-read instructions. Note that all table related instructions require
two instruction cycles to complete their operation.
Rev. 1.20
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Touch A/D Flash MCU with OCVP
Table Read Program Example
tempreg1 db ? ; temporary register #1
tempreg2 db ? ; temporary register #2
:
mov a,06h ; initialise low table pointer - note that this address is referenced
mov tblp,a ; to the last page or the page that tbhp pointed
mov a,1fh ; initialise high table pointer
mov tbhp,a
:
tabrd
tempreg1 ; transfers value in table referenced by table pointer data at program
; memory address "1F06H" transferred to tempreg1 and TBLH
dec tblp ; reduce value of table pointer by one
tabrd
tempreg2 ; transfers value in table referenced by table pointer data at program
; memory address "1F05H" transferred to tempreg2 and TBLH in this
; example the data "1AH" is transferred to tempreg1 and data "0FH" to
; register tempreg2
:
org 1F00h ; sets initial address of program memory
dc 00Ah, 00Bh, 00Ch, 00Dh, 00Eh, 00Fh, 01Ah, 01Bh
:
In Circuit Programming – ICP
The provision of Flash type Program Memory provides the user with a means of convenient and
easy upgrades and modifications to their programs on the same device.
As an additional convenience, Holtek has provided a means of programming the microcontroller incircuit using a 4-pin interface. This provides manufacturers with the possibility of manufacturing
their circuit boards complete with a programmed or un-programmed microcontroller, and then
programming or upgrading the program at a later stage. This enables product manufacturers to easily
keep their manufactured products supplied with the latest program releases without removal and reinsertion of the device.
Holtek Writer Pins
MCU Programming Pins
Pin Description
ICPDA
PA0
Programming Serial Data/Address
ICPCK
PA2
Programming Clock
VDD
VDD
Power Supply
VSS
VSS
Ground
The Program Memory and EEPROM data memory can be programmed serially in-circuit using this
4-wire interface. Data is downloaded and uploaded serially on a single pin with an additional line
for the clock. Two additional lines are required for the power supply. The technical details regarding
the in-circuit programming of the device are beyond the scope of this document and will be supplied
in supplementary literature.
During the programming process, the user must take care of the ICPDA and ICPCK pins for data
and clock programming purposes to ensure that no other outputs are connected to these two pins.
Rev. 1.20
38
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
W�ite� Conne�to�
Signals
MCU P�og�a��ing
Pins
W�ite�_VDD
VDD
ICPDA
PA0
ICPCK
PA2
W�ite�_VSS
VSS
*
*
To othe� Ci��uit
Note: * may be resistor or capacitor. The resistance of * must be greater than 1k or the capacitance
of * must be less than 1nF.
On-Chip Debug Support – OCDS
There are EV chips named BS87BV12A, BS87CV16A and BS87DV20A which are used to emulate
the real MCU device named BS87B12A-3, BS87C16A-3 and BS87D20A-3 respectively. The EV
chip device also provides the "On-Chip Debug" function to debug the real MCU device during
development process. The EV chips and real MCU devices are almost functional compatible except
the "On-Chip Debug" function. Users can use the EV chip device to emulate the real MCU device
behaviors by connecting the OCDSDA and OCDSCK pins to the Holtek HT-IDE development tools.
The OCDSDA pin is the OCDS Data/Address input/output pin while the OCDSCK pin is the OCDS
clock input pin. When users use the EV chip device for debugging, the corresponding pin functions
shared with the OCDSDA and OCDSCK pins in the real MCU 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. 1.20
Holtek e-Link Pins
EV Chip OCDS Pins
Pin Description
OCDSDA
OCDSDA
On-Chip Debug Support Data/Address input/output
OCDSCK
OCDSCK
On-Chip Debug Support Clock input
VDD
VDD
Power Supply
VSS
VSS
Ground
39
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
Data Memory
The Data Memory is an 8-bit wide RAM internal memory and is the location where temporary
information is stored.
Structure
Divided into two types, the first of Data Memory is an area of RAM where special function registers
are located. These registers have fixed locations and are necessary for correct operation of the
device. Many of these registers can be read from and written to directly under program control,
however, some remain protected from user manipulation. The second area of Data Memory is
reserved for general purpose use. All locations within this area are read and write accessible under
program control.
The Data Memory is subdivided into several sectors, all of which are implemented in 8-bit wide
Memory. Each of the Data Memory sectors is categorized into two types, the Special Purpose Data
Memory and the General Purpose Data Memory.
The address range of the Special Purpose Data Memory for the device is from 00H to 7FH while the
General Purpose Data Memory address range is from 80H to FFH. Switching between the different
Data Memory sectors is achieved by properly setting the Memory Pointers to correct value.
Device
Special Purpose Data Memory
General Purpose Data Memory
Sector : Address
Capacity
Sector : Address
BS87B12A-3
0~2: 00H~7FH
(EEC @40H only accessible in Sector 1)
384 x 8
0~2: 80H~FFH
BS87C16A-3
0~3: 00H~7FH
(EEC @40H only accessible in Sector 1)
512 x 8
0~3: 80H~FFH
BS87D20A-3
0~5: 00H~7FH
(EEC @40H only accessible in Sector 1)
768 x 8
0~5: 80H~FFH
Data Memory Summary
00H
Special Purpose
Data Memory
40H in Sector 1
(Sector 0 ~ Sector 1)
5FH in Sector 1
7FH
80H
General Purpose
Data Memory
(Sector 0 ~ Sector N)
FFH
Sector 0
Sector 1
Sector N
Note: N=2 for BS87B12A-3; N=3 for BS87C16A-3; N=5 for BS87D20A-3
Data Memory Structure
Rev. 1.20
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December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
Data Memory Addressing
For these devices that support the extended instructions, there is no Bank Pointer for Data Memory.
For Data Memory the desired Sector is pointed by the MP1H or MP2H register and the certain
Data Memory address in the selected sector is specified by the MP1L or MP2L register when using
indirect addressing access.
Direct Addressing can be used in all sectors using the corresponding instruction which can address
all available data memory space. For the accessed data memory which is located in any data
memory sectors except sector 0, the extended instructions can be used to access the data memory
instead of using the indirect addressing access. The main difference between standard instructions
and extended instructions is that the data memory address "m" in the extended instructions can be
from 10 to 11 bits depending upon which device is selected, the high byte indicates a sector and the
low byte indicates a specific address.
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 programming 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.
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".
Rev. 1.20
41
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
00H
01H
02H
03H
04H
05H
06H
07H
08H
09H
0AH
0BH
0CH
0DH
0EH
0FH
10H
11H
12H
13H
14H
15H
16H
17H
18H
19H
1AH
1BH
1CH
1DH
1EH
1FH
20H
21H
22H
23H
24H
25H
26H
27H
28H
29H
2AH
2BH
2CH
2DH
2EH
2FH
30H
31H
32H
33H
34H
35H
36H
37H
38H
39H
3AH
3BH
3CH
3DH
3EH
3FH
Sector 0~2
IAR0
MP0
IAR1
MP1L
MP1H
ACC
PCL
TBLP
TBLH
TBHP
STATUS
SMOD
IAR2
MP2L
MP2H
INTEG
INTC0
INTC1
INTC2
INTC3
PA
PAC
PAPU
PAWU
SLEDC0
SLEDC1
WDTC
TBC
PSCR
LVRC
EEA
EED
PB
PBC
PBPU
SIMTOC
SIMC0
SIMC1
SIMD
SIMA/SIMC2
USR
UCR1
UCR2
BRG
TXR_RXR
SADOL
SADOH
SADC0
SADC1
ACERL
TMPC0
SLCDC0
SLCDC1
SLCDC2
40H
41H
42H
43H
44H
45H
46H
47H
48H
49H
4AH
4BH
4CH
4DH
4EH
4FH
50H
51H
52H
53H
54H
55H
56H
57H
58H
59H
5AH
5BH
5CH
5DH
5EH
5FH
60H
61H
62H
63H
64H
65H
66H
67H
68H
69H
6AH
6BH
6CH
6DH
6EH
6FH
70H
71H
72H
73H
74H
75H
76H
77H
78H
79H
7AH
7BH
7CH
7DH
7EH
7FH
LVDC
OCVPC0
PC
PCC
PCPU
IFS
CTRL
OCVPC1
OCVPC2
Sector 0, 2
OCVPC3
Sector 1
EEC
TKTMR
TKC0
TK16DL
TK16DH
TKC1
TKM016DL
TKM016DH
TKM0ROL
TKM0ROH
TKM0C0
TKM0C1
TKM116DL
TKM116DH
TKM1ROL
TKM1ROH
TKM1C0
TKM1C1
TKM216DL
TKM216DH
TKM2ROL
TKM2ROH
TKM2C0
TKM2C1
CTM0C0
CTM0C1
CTM0DL
CTM0DH
CTM0AL
CTM0AH
PTM0C0
PTM0C1
PTM0DL
PTM0DH
PTM0AL
PTM0AH
PTM0RPL
PTM0RPH
OCVPDA
OCVPOCAL
OCVPCCAL
: Unused, read as 00H
Special Purpose Data Memory Structure – BS87B12A-3
Rev. 1.20
42
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
00H
01H
02H
03H
04H
0�H
0�H
07H
08H
09H
0AH
0BH
0CH
0DH
0EH
0FH
10H
11H
12H
13H
14H
1�H
1�H
17H
18H
19H
1AH
1BH
1CH
1DH
1EH
1FH
20H
21H
22H
23H
24H
2�H
2�H
27H
28H
29H
2AH
2BH
2CH
2DH
2EH
2FH
30H
31H
32H
33H
34H
3�H
3�H
37H
38H
39H
3AH
3BH
3CH
3DH
3EH
3FH
Se�to� 0~3
IAR0
MP0
IAR1
MP1L
MP1H
ACC
PCL
TBLP
TBLH
TBHP
STATUS
SMOD
IAR2
MP2L
MP2H
INTEG
INTC0
INTC1
INTC2
INTC3
PA
PAC
PAPU
PAWU
SLEDC0
SLEDC1
WDTC
TBC
PSCR
LVRC
EEA
EED
PB
PBC
PBPU
SIMTOC
SIMC0
SIMC1
SIMD
SIMA/SIMC2
USR
UCR1
UCR2
BRG
TXR_RXR
SADOL
SADOH
SADC0
SADC1
ACERL
TMPC0
SLCDC0
SLCDC1
SLCDC2
SLCDC3
LVDC
OCVPC0
PC
PCC
PCPU
MFI
CTRL
OCVPC1
OCVPC2
40H
41H
42H
43H
44H
4�H
4�H
47H
48H
49H
4AH
4BH
4CH
4DH
4EH
4FH
�0H
�1H
�2H
�3H
�4H
��H
��H
�7H
�8H
�9H
�AH
�BH
�CH
�DH
�EH
�FH
�0H
�1H
�2H
�3H
�4H
��H
��H
�7H
�8H
�9H
�AH
�BH
�CH
�DH
�EH
�FH
70H
71H
72H
73H
74H
7�H
7�H
77H
78H
79H
7AH
7BH
7CH
7DH
7EH
7FH
Se�to� 0� 2~3 Se�to� 1
EEC
OCVPC3
PD
PDC
PDPU
TKTMR
TKC0
TK1�DL
TK1�DH
TKC1
TKM01�DL
TKM01�DH
TKM0ROL
TKM0ROH
TKM0C0
TKM0C1
TKM11�DL
TKM11�DH
TKM1ROL
TKM1ROH
TKM1C0
TKM1C1
TKM21�DL
TKM21�DH
TKM2ROL
TKM2ROH
TKM2C0
TKM2C1
TKM31�DL
TKM31�DH
TKM3ROL
TKM3ROH
TKM3C0
TKM3C1
CTM0C0
CTM0C1
CTM0DL
CTM0DH
CTM0AL
CTM0AH
PTM0C0
PTM0C1
PTM0DL
PTM0DH
PTM0AL
PTM0AH
PTM0RPL
PTM0RPH
PTM1C0
PTM1C1
PTM1DL
PTM1DH
PTM1AL
PTM1AH
PTM1RPL
PTM1RPH
OCVPDA
OCVPOCAL
OCVPCCAL
: Unused� �ead as 00H
Special Purpose Data Memory Structure – BS87C16A-3
Rev. 1.20
43
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
00H
01H
02H
03H
04H
0�H
0�H
07H
08H
09H
0AH
0BH
0CH
0DH
0EH
0FH
10H
11H
12H
13H
14H
1�H
1�H
17H
18H
19H
1AH
1BH
1CH
1DH
1EH
1FH
20H
21H
22H
23H
24H
2�H
2�H
27H
28H
29H
2AH
2BH
2CH
2DH
2EH
2FH
30H
31H
32H
33H
34H
3�H
3�H
37H
38H
39H
3AH
3BH
3CH
3DH
3EH
3FH
Se�to� 0~�
IAR0
MP0
IAR1
MP1L
MP1H
ACC
PCL
TBLP
TBLH
TBHP
STATUS
SMOD
IAR2
MP2L
MP2H
INTEG
INTC0
INTC1
INTC2
INTC3
PA
PAC
PAPU
PAWU
SLEDC0
SLEDC1
WDTC
TBC
PSCR
LVRC
EEA
EED
PB
PBC
PBPU
SIMTOC
SIMC0
SIMC1
SIMD
SIMA/SIMC2
USR
UCR1
UCR2
BRG
TXR_RXR
SADOL
SADOH
SADC0
SADC1
ACERL
TMPC0
SLCDC0
SLCDC1
SLCDC2
SLCDC3
LVDC
OCVPC0
PC
PCC
PCPU
MFI
CTRL
OCVPC1
OCVPC2
40H
41H
42H
43H
44H
4�H
4�H
47H
48H
49H
4AH
4BH
4CH
4DH
4EH
4FH
�0H
�1H
�2H
�3H
�4H
��H
��H
�7H
�8H
�9H
�AH
�BH
�CH
�DH
�EH
�FH
�0H
�1H
�2H
�3H
�4H
��H
��H
�7H
�8H
�9H
�AH
�BH
�CH
�DH
�EH
�FH
70H
71H
72H
73H
74H
7�H
7�H
77H
78H
79H
7AH
7BH
7CH
7DH
7EH
7FH
Se�to� 0� 2~�
Se�to� 1
EEC
OCVPC3
PD
PE
PDC
PEC
PDPU
PEPU
TKTMR
PF
TKC0
PFC
TK1�DL
PFPU
TK1�DH
SLEDC2
TKC1
SLCDC4
SLCDC�
TKM01�DL
TMPC1
TKM01�DH
TKM0ROL
TKM0ROH
TKM0C0
TKM0C1
TKM11�DL
TKM11�DH
TKM1ROL
TKM1ROH
TKM1C0
TKM1C1
TKM21�DL
TKM21�DH
TKM2ROL
TKM2ROH
TKM2C0
TKM2C1
CTM1C0
TKM31�DL
CTM1C1
TKM31�DH
CTM1DL
TKM3ROL
CTM1DH
TKM3ROH
CTM1AL
TKM3C0
CTM1AH
TKM3C1
CTM0C0
CTM0C1
CTM0DL
CTM0DH
CTM0AL
CTM0AH
PTM0C0
PTM0C1
PTM0DL
PTM0DH
PTM0AL
PTM0AH
PTM0RPL
PTM0RPH
TKM41�DL
TKM41�DH
TKM4ROL
TKM4ROH
TKM4C0
TKM4C1
PTM1C0
PTM1C1
PTM1DL
PTM1DH
PTM1AL
PTM1AH
PTM1RPL
PTM1RPH
OCVPDA
OCVPOCAL
OCVPCCAL
: Unused� �ead as 00H
Special Purpose Data Memory Structure – BS87D20A-3
Rev. 1.20
44
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
Special Function Register Description
Most of the Special Function Register details will be described in the relevant functional section.
However, several registers require a separate description in this section.
Indirect Addressing Registers – IAR0, IAR1, IAR2
The Indirect Addressing Registers, IAR0, IAR1 and IAR2, although having their locations in normal
RAM register space, do not actually physically exist as normal registers. The method of indirect
addressing for RAM data manipulation uses these Indirect Addressing Registers and Memory
Pointers, in contrast to direct memory addressing, where the actual memory address is specified.
Actions on the IAR0, IAR1 and IAR2 registers will result in no actual read or write operation to
these registers but rather to the memory location specified by their corresponding Memory Pointers,
MP0, MP1L/MP1H or MP2L/MP2H. Acting as a pair, IAR0 and MP0 can together access data
only from Sector 0 while the IAR1 register together with MP1L/MP1H register pair and IAR2
register together with MP2L/MP2H register pair can access data from any Data Memory sector. As
the Indirect Addressing Registers are not physically implemented, reading the Indirect Addressing
Registers indirectly will return a result of "00H" and writing to the registers indirectly will result in
no operation.
Memory Pointers – MP0, MP1H/MP1L, MP2H/MP2L
Five Memory Pointers, known as MP0, MP1L, MP1H, MP2L and MP2H, are provided. These
Memory Pointers are physically implemented in the Data Memory and can be manipulated in the
same way as normal registers providing a convenient way with which to address and track data.
When any operation to the relevant Indirect Addressing Registers is carried out, the actual address
that the microcontroller is directed to is the address specified by the related Memory Pointer. MP0,
together with Indirect Addressing Register, IAR0, are used to access data from Sector 0, while
MP1L/MP1H together with IAR1 and MP2L/MP2H together with IAR2 are used to access data
from all data sectors according to the corresponding MP1H or MP2H register. Direct Addressing can
be used in all data sectors using the corresponding instruction which can address all available data
memory space.
Indirect Addressing Program Example
• Example 1
data .section ‘data’
adres1 db ?
adres2 db ?
adres3 db ?
adres4 db ?
block db ?
code .section at 0 code
org 00h
start:
mov a,04h ;
mov block,a
mov a,offset adres1 ;
mov mp0,a ;
loop:
clr IAR0 ;
inc mp0;
sdz block ;
jmp loop
continue:
Rev. 1.20
setup size of block
Accumulator loaded with first RAM address
setup memory pointer with first RAM address
clear the data at address defined by MP0
increment memory pointer
check if last memory location has been cleared
45
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
• Example 2
data .section ‘data’
adres1 db ?
adres2 db ?
adres3 db ?
adres4 db ?
block db ?
code .section at 0 ‘code’
org 00h
start:
mov a,04h ; setup size of block
mov block,a
mov a,01h ; setup the memory sector
mov mp1h,a
mov a,offset adres1 ; Accumulator loaded with first RAM address
mov mp1l,a ; setup memory pointer with first RAM address
loop:
clr IAR1 ; clear the data at address defined by MP1
inc mp1l ; increment memory pointer MP1L
sdz block ; check if last memory location has been cleared
jmp loop
continue:
The important point to note here is that in the example shown above, no reference is made to specific
RAM addresses.
Direct Addressing Program Example using extended instructions
data .section ‘data’
temp db ?
code .section at 0 code
org 00h
start:
lmov a,[m]; move [m] data to acc
lsub a, [m+1] ; compare [m] and [m+1] data
snz c; [m]>[m+1]?
jmp continue; no
lmov a,[m] ; yes, exchange [m] and [m+1] data
mov temp,a
lmov a,[m+1]
lmov [m],a
mov a,temp
lmov [m+1],a
continue:
Note: Here "m" is a data memory address located in any data memory sectors. For example,
m=1F0H, it indicates address 0F0H in Sector 1.
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.
Rev. 1.20
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Touch A/D Flash MCU with OCVP
Program Counter Low Register – PCL
To provide additional program control functions, the low byte of the Program Counter is made
accessible to programmers by locating it within the Special Purpose area of the Data Memory. By
manipulating this register, direct jumps to other program locations are easily implemented. Loading
a value directly into this PCL register will cause a jump to the specified Program Memory location;
however, as the register is only 8-bit wide, only jumps within the current Program Memory page are
permitted. When such operations are used, note that a dummy cycle will be inserted.
Look-up Table Registers – TBLP, TBHP, TBLH
These three special function registers are used to control operation of the look-up table which
is stored in the Program Memory. The TBLP and TBHP registers are the table pointer pair and
indicates the location where the table data is located. Their value must be setup before any table
read instructions are executed. Their value can be changed, for example using the "INC" or "DEC"
instructions, allowing for easy table data pointing and reading. TBLH is the location where the high
order byte of the table data is stored after a table read data instruction has been executed. Note that
the lower order table data byte is transferred to a user defined location.
Status Register – STATUS
This 8-bit register contains the zero flag (Z), carry flag (C), auxiliary carry flag (AC), overflow flag
(OV), SC flag, CZ flag, power down flag (PDF), and watchdog time-out flag (TO). These arithmetic/
logical operation and system management flags are used to record the status and operation of the
microcontroller.
With the exception of the TO and PDF flags, bits in the status register can be altered by instructions
like most other registers. Any data written into the status register will not change the TO or PDF flag.
In addition, operations related to the status register may give different results due to the different
instruction operations. The TO flag can be affected only by a system power-up, a WDT time-out or
by executing the "CLR WDT" or "HALT" instruction. The PDF flag is affected only by executing
the "HALT" or "CLR WDT" instruction or during a system power-up.
The Z, OV, AC, C, SC and CZ flags generally reflect the status of the latest operations.
• C is set if an operation results in a carry during an addition operation or if a borrow does not take
place during a subtraction operation; otherwise C is cleared. C is also affected by a rotate through
carry instruction.
• AC is set if an operation results in a carry out of the low nibbles in addition, or no borrow from
the high nibble into the low nibble in subtraction; otherwise AC is cleared.
• Z is set if the result of an arithmetic or logical operation is zero; otherwise Z is cleared.
• OV is set if an operation results in a carry into the highest-order bit but not a carry out of the
highest-order bit, or vice versa; otherwise OV is cleared.
• 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.
• SC is the result of the "XOR" operation which is performed by the OV flag and the MSB of the
current instruction operation result.
• CZ is the operational result of different flags for different instructions. Refer to register
definitions for more details.
Rev. 1.20
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December 05, 2016
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Touch A/D Flash MCU with OCVP
In addition, on entering an interrupt sequence or executing a subroutine call, the status register will
not be pushed onto the stack automatically. If the contents of the status registers are important and if
the subroutine can corrupt the status register, precautions must be taken to correctly save it.
STATUS Register
Bit
7
6
5
4
3
2
1
0
Name
SC
CZ
TO
PDF
OV
Z
AC
C
R/W
R
R
R
R
R/W
R/W
R/W
R/W
POR
×
×
0
0
×
×
×
×
"×": unknown
Rev. 1.20
Bit 7
SC: The result of the "XOR" operation which is performed by the OV flag and the
MSB of the instruction operation result.
Bit 6
CZ: The operational result of different flags for different instructions.
For SUB/SUBM/LSUB/LSUBM instructions, the CZ flag is equal to the Z flag.
For SBC/ SBCM/ LSBC/ LSBCM instructions, the CZ flag is the "AND" operation
result which is performed by the previous operation CZ flag and current operation zero
flag. For other instructions, the CZ flag will not be affected.
Bit 5
TO: Watchdog Time-out flag
0: After power up or executing the "CLR WDT" or "HALT" instruction
1: A watchdog time-out occurred
Bit 4
PDF: Power down flag
0: After power up or executing the "CLR WDT" instruction
1: By executing the "HALT" instruction
Bit 3
OV: Overflow flag
0: No overflow
1: An operation results in a carry into the highest-order bit but not a carry out of the
highest-order bit or vice versa
Bit 2
Z: Zero flag
0: The result of an arithmetic or logical operation is not zero
1: The result of an arithmetic or logical operation is zero
Bit 1
AC: Auxiliary flag
0: No auxiliary carry
1: An operation results in a carry out of the low nibbles, in addition, or no borrow
from the high nibble into the low nibble in subtraction
Bit 0
C: Carry flag
0: No carry-out
1: An operation results in a carry during an addition operation or if a borrow does
not take place during a subtraction operation
The "C" flag is also affected by a rotate through carry instruction.
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December 05, 2016
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Touch A/D Flash MCU with OCVP
EEPROM Data Memory
These devices contain an area of internal EEPROM Data Memory. EEPROM, which stands for
Electrically Erasable Programmable Read Only Memory, is by its nature a non-volatile form
of re-programmable memory, with data retention even when its power supply is removed. By
incorporating this kind of data memory, a whole new host of application possibilities are made
available to the designer. The availability of EEPROM storage allows information such as product
identification numbers, calibration values, specific user data, system setup data or other product
information to be stored directly within the product microcontroller. The process of reading and
writing data to the EEPROM memory has been reduced to a very trivial affair.
Device
Capacity
Address
64 × 8
00H ~ 3FH
BS87B12A-3
BS87C16A-3
BS87D20A-3
EEPROM Data Memory Structure
The EEPROM Data Memory capacity is 64×8 bits for the series of devices. Unlike the Program
Memory and RAM Data Memory, the EEPROM Data Memory is not directly mapped into memory
space and is therefore not directly addressable in the same way as the other types of memory. Read
and Write operations to the EEPROM are carried out in single byte operations using an address and
data register in sector 0 and a single control register in sector 1.
EEPROM Registers
Three registers control the overall operation of the internal EEPROM Data Memory. These are the
address register, EEA, the data register, EED and a single control register, EEC. As both the EEA
and EED registers are located in sector 0, they can be directly accessed in the same was as any other
Special Function Register. The EEC register, however, being located in sector 1, can be read from
or written to indirectly using the MP1H/MP1L or MP2H/MP2L Memory Pointer pair and Indirect
Addressing Register, IAR1 or IAR2. Because the EEC control register is located at address 40H
in sector 1, the Memory Pointer low byte register, MP1L or MP2L, must first be set to the value
40H and the Memory Pointer high byte register, MP1H or MP2H, 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
—
—
EEA5
EEA4
EEA3
EEA2
EEA1
EEA0
EED
D7
D6
D5
D4
D3
D2
D1
D0
EEC
—
—
—
—
WREN
WR
RDEN
RD
EEPROM Registers List
EEA Register
Rev. 1.20
Bit
7
6
5
4
3
2
1
0
Name
—
—
EEA5
EEA4
EEA3
EEA2
EEA1
EEA0
R/W
—
—
R/W
R/W
R/W
R/W
R/W
R/W
POR
—
—
0
0
0
0
0
0
Bit 7~6
Unimplemented, read as 0.
Bit 5~0
EEA5~EEA0: Data EEPROM address bit 5 ~ bit 0
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Touch A/D Flash MCU with OCVP
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
D7~D0: Data EEPROM data bit 7~bit0
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 3
WREN: 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 2
WR: EEPROM write control
0: Write cycle has finished
1: Activate a write cycle
This is the Data EEPROM Write Control Bit and when set high by the application
program will activate a write cycle. This bit will be automatically reset to zero by the
hardware after the write cycle has finished. Setting this bit high will have no effect if
the WREN has not first been set high.
Bit 1
RDEN: Data EEPROM read enable
0: Disable
1: Enable
This is the Data EEPROM Read Enable Bit which must be set high before Data
EEPROM read operations are carried out. Clearing this bit to zero will inhibit Data
EEPROM read operations.
Bit 0
RD: EEPROM read control
0: Read cycle has finished
1: Activate a read cycle
This is the Data EEPROM Read Control Bit and when set high by the application
program will activate a read cycle. This bit will be automatically reset to zero by the
hardware after the read cycle has finished. Setting this bit high will have no effect if
the RDEN has not first been set high.
Note: The WREN, WR, RDEN and RD can not be set to "1" at the same time in one instruction. The
WR and RD can not be set to "1" at the same time.
Rev. 1.20
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Reading Data from the EEPROM
To read data from the EEPROM, the EEPROM address of the data to be read must first be placed in
the EEA register or EEAL/EEAH register pair. Then the read enable bit, RDEN, in the EEC register
must be set high to enable the read function. If the RD bit in the EEC register is now set high, a
read cycle will be initiated. Setting the RD bit high will not initiate a read operation if the RDEN bit
has not been set. When the read cycle terminates, the RD bit will be automatically cleared to zero,
after which the data can be read from the EED register. The data will remain in the EED register
until another read or write operation is executed. The application program can poll the RD bit to
determine when the data is valid for reading.
Writing Data to the EEPROM
To write data to the EEPROM, the 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 initiate a write cycle 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 successfully. 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 high again after the write cycle has started.
Note that setting the WR bit high will not initiate a write cycle if the WREN bit has not been set. As
the EEPROM write cycle is controlled using an internal timer whose operation is asynchronous to
microcontroller system clock, a certain time will elapse before the data will have been written into
the EEPROM. Detecting when the write cycle has finished can be implemented either by polling the
WR bit in the EEC register or by using the EEPROM interrupt. When the write cycle terminates,
the WR bit will be automatically cleared to zero by the microcontroller, informing the user that the
data has been written to the EEPROM. The application program can therefore poll the WR bit to
determine when the write cycle has ended.
Write Protection
Protection against inadvertent write operation is provided in several ways. After the device is
powered on, the Write Enable bit in the control register will be cleared preventing any write
operations. Also at power-on the Memory Pointer high byte register, MP1H or MP2H, will be reset
to zero, which means that Data Memory sector 0 will be selected. As the EEPROM control register
is located in sector 1, this adds a further measure of protection against spurious write operations.
During normal program operation, ensuring that the Write Enable bit in the control register is
cleared will safeguard against incorrect write operations.
EEPROM Interrupt
The EEPROM write interrupt is generated when an EEPROM write cycle has ended. The EEPROM
interrupt must first be enabled by setting the DEE bit in the relevant interrupt register. When an
EEPROM write cycle ends, the DEF request flag will be set. If the global, EEPROM interrupt is
enabled and the stack is not full, a jump to the associated Interrupt vector will take place. When the
interrupt is serviced the EEPROM interrupt flag will be automatically reset.
Rev. 1.20
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BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
Programming Considerations
Care must be taken that data is not inadvertently written to the EEPROM. Protection can be
enhanced by ensuring that the Write Enable bit is normally cleared to zero when not writing. Also the
Memory Pointer high byte register could be normally cleared to zero as this would inhibit access to
sector 1 where the EEPROM control register exist. Although certainly not necessary, consideration
might be given in the application program to the checking of the validity of new write data by a
simple read back process. When writing data the WR bit must be set high immediately after the
WREN bit has been set high, to ensure the write cycle executes correctly. The global interrupt bit
EMI should also be cleared before a write cycle is executed and then re-enabled after the write cycle
starts. Note that the device should not enter the IDLE or SLEEP mode until the EEPROM read or
write operation is totally complete. Otherwise, the EEPROM read or write operation will fail.
Programming Examples
• Reading data from the EEPROM – polling method
MOV A, EEPROM_ADRES MOV EEA, A
MOV A, 040H
MOV MP1L, A
MOV A, 01H
MOV MP1H, A
SET IAR1.1
SET IAR1.0
BACK:
SZ IAR1.0
JMP BACK
CLR IAR1
CLR MP1H
MOV A, EED
MOV READ_DATA, A
; user defined address
; setup memory pointer low byte MP1L
; MP1L points to EEC register
; setup Memory Pointer high byte MP1H
; 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 MP1L, A
MOV A, 01H
MOV MP1H, A
CLR EMI
SET IAR1.3 SET IAR1.2 SET EMI
BACK:
SZ IAR1.2
JMP BACK
CLR IAR1
CLR MP1H
Rev. 1.20
; user defined address
; user defined data
; setup memory pointer low byte MP1L
; MP1L points to EEC register
; setup Memory Pointer high byte MP1H
; set WREN bit, enable write operations
; start Write Cycle - set WR bit
; check for write cycle end
; disable EEPROM write
52
December 05, 2016
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Touch A/D Flash MCU with OCVP
Oscillators
Various oscillator types offer the user a wide range of functions according to their various application
requirements. The flexible features of the oscillator functions ensure that the best optimisation can
be achieved in terms of speed and power saving. Oscillator selections and operation are selected
through a combination of configuration options and relevant control registers.
Oscillator Overview
In addition to being the source of the main system clock the oscillators also provide clock sources
for the Watchdog Timer and Time Base Interrupts. External oscillators requiring some external
components as well as fully integrated internal oscillators, requiring no external components, are
provided to form a wide range of both fast and slow system oscillators. All oscillator options are
selected through the corresponding configuration options. The higher frequency oscillators provide
higher performance but carry with it the disadvantage of higher power requirements, while the
opposite is of course true for the lower frequency oscillators. With the capability of dynamically
switching between fast and slow system clock, the device has the flexibility to optimize the
performance/power ratio, a feature especially important in power sensitive portable applications.
Note that the external low speed crystal oscillator, LXT, is only available for the BS87C16A-3 and
BS87D20A-3 devices
Name
Frequency
Internal High Speed RC
Type
HIRC
8/12/16 MHz
Pins
—
Internal Low Speed RC
LIRC
32 kHz
—
External Low Speed Crystal*
LXT*
32.768 kHz
XT1/XT2
Oscillator Types
System Clock Configurations
There are three methods of generating the system clock, one high speed oscillators and two low
speed oscillators for all devices. The high speed oscillator is the internal 8/12/16 MHz RC oscillator,
HIRC. The two low speed oscillators are the internal 32 kHz RC oscillator, LIRC, and the external
32.768 kHz crystal oscillator, LXT. Selecting whether the low or high speed oscillator is used as the
system oscillator is implemented using the HLCLK and CKS2~CKS0 bits in the SMOD register and
as the system clock can be dynamically selected.
The actual source clock used for the low speed oscillators is chosen via the corresponding
configuration option. The frequency of the slow speed or high speed system clock is determined
using the HLCLK and CKS2~CKS0 bits in the SMOD register. Note that two oscillator selections
must be made namely one high speed and one low speed system oscillators. It is not possible to
choose a no-oscillator selection for either the high or low speed oscillator.
Rev. 1.20
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December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
fH
fH/2
fH/4
High Speed Oscillator
fH/8
HIRC
Prescaler
fSYS
fH/16
fH/32
fH/64
Low Speed Oscillator
LIRC
fLIRC
fSUB
LXT *
HLCLK,
CKS2~CKS0 bits
fSUB
fLXT
Configuration
Option
Note: The LXT oscillator is only available for BS87C16A-3 and BS87D20A-3
System Clock Configurations
Internal High Speed RC Oscillator – HIRC
The internal RC oscillator is a fully integrated system oscillator requiring no external components.
The internal RC oscillator has a power-on default frequency of 8MHz but can be selected to be
either 8MHz, 12MHz or 16MHz via a configuration option and the HIRCS1 and HIRCS0 bits in
the CTRL register. 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.
Internal 32kHz Oscillator – LIRC
The Internal 32 kHz System Oscillator is one of the low frequency oscillator choices, which
is selected via a configuration option for the BS87C16A-3 and BS87D20A-3 devices. For the
BS87B12A-3 device there is only one low frequency oscillator known as the LIRC oscillator. It
is a fully integrated RC oscillator with a typical frequency of 32 kHz 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.
Rev. 1.20
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December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
External 32.768 kHz Crystal Oscillator – LXT – for BS87C16A-3/BS87D20A-3
The External 32.768 kHz Crystal System Oscillator is one of the low frequency oscillator choices,
which is selected via a configuration option. This clock source has a fixed frequency of 32.768 kHz
and requires a 32.768 kHz crystal to be connected between pins XT1 and XT2. The external resistor
and capacitor components connected to the 32.768 kHz crystal are necessary to provide oscillation.
For applications where precise frequencies are essential, these components may be required to
provide frequency compensation due to different crystal manufacturing tolerances. During power-up
there is a time delay associated with the LXT oscillator waiting for it to start-up.
When the microcontroller enters the SLEEP or IDLE Mode, the system clock is switched off to stop
microcontroller activity and to conserve power. However, in many microcontroller applications
it may be necessary to keep the internal timers operational even when the microcontroller is in
the SLEEP or IDLE Mode. To do this, another clock, independent of the system clock, must be
provided.
However, for some crystals, to ensure oscillation and accurate frequency generation, it is necessary
to add two small value external capacitors, C1 and C2. The exact values of C1 and C2 should be
selected in consultation with the crystal or resonator manufacturer’s specification. The external
parallel feedback resistor, Rp, is required.
The configuration option determines if the XT1/XT2 pins are used for the LXT oscillator or as I/O
or other pin-shared functions.
• If the LXT oscillator is not used for any clock source, the XT1/XT2 pins can be used as normal I/O
or other pin-shared functions.
• If the LXT oscillator is used for any clock source, the 32.768 kHz crystal should be connected to
the XT1/XT2 pins.
For oscillator stability and to minimise the effects of noise and crosstalk, it is important to ensure
that the crystal and any associated resistors and capacitors along with interconnecting lines are all
located as close to the MCU as possible.
C1
Internal
Oscillator
Circuit
XT1
32.7�8
kHz
Inte�nal RC
Os�illato�
RP
To inte�nal
�i��uits
XT2
C2
Note: 1. RP� C1 and C2 a�e �equi�ed.
2. Although not shown XT1/XT2 pins have a pa�asiti�
�apa�itan�e of a�ound 7pF.
External LXT Oscillator
LXT Oscillarot C1 and C2 Values
Crystal Frequency
C1
C2
32.768kHz
10pF
10pF
Note: 1. C1 and C2 value are for guidance only.
2. RP=5MΩ~10MΩ is recommended.
32.768kHz Crystal Capacitor Recommended Value
Rev. 1.20
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December 05, 2016
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Touch A/D Flash MCU with OCVP
LXT Oscillator Low Power Function
The LXT oscillator can function in one of two modes, the Quick Start Mode and the Low Power
Mode. The mode selection is executed using the LXTLP bit in the CTRL register.
LXTLP
LXT Mode
0
Quick Start
1
Low Power
After power on, the LXTLP bit will be automatically cleared to zero ensuring that the LXT oscillator
is in the Quick Start operating mode. In the Quick Start Mode the LXT oscillator will power up
and stabilise quickly. However, after the LXT oscillator has fully powered up it can be placed
into the Low-power mode by setting the LXTLP bit high. The oscillator will continue to run but
with reduced current consumption, as the higher current consumption is only required during the
LXT oscillator start-up. In power sensitive applications, such as battery applications, where power
consumption must be kept to a minimum, it is therefore recommended that the application program
sets the LXTLP bit high about 2 seconds after power-on.
It should be noted that, no matter what condition the LXTLP bit is set to, the LXT oscillator will
always function normally. The only difference is that it will take more time to start up if in the Lowpower mode.
Rev. 1.20
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Operating Modes and System Clocks
Present day applications require that their microcontrollers have high performance but often still
demand that they consume as little power as possible, conflicting requirements that are especially
true in battery powered portable applications. The fast clocks required for high performance will
by their nature increase current consumption and of course vice-versa lower speed clocks reduce
current consumption. As Holtek has provided these devices with both high and low speed clock
sources and the means to switch between them dynamically, the user can optimise the operation of
their microcontroller to achieve the best performance/power ratio.
System Clocks
Each device has different clock sources for both the CPU and peripheral function operation. By
providing the user with a wide range of clock selections 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 is sourced from the HIRC oscillator. The low speed system clock source can be
sourced from the internal clock fSUB. If fSUB is selected then it can be sourced by either the LXT or
LIRC oscillators, selected via a configuration option. The other choice, which is a divided version of
the high speed system oscillator has a range of fH/2~fH/64.
fH
fH/2
fH/4
High Speed Os�illato�
fH/8
HIRC
P�es�ale�
fSYS
fH/1�
fH/32
fH/�4
Low Speed Os�illato�
LIRC
fLIRC
HLCLK�
CKS2~CKS0 �its
fSUB
LXT *
fLXT
Configu�ation
Option
fSUB
fSYS
fSYS/4
fSUB
fPSC0
P�es�ale� 0
Ti�e Base 0
fH
CLKSEL0[1:0]
fSYS
fSYS/4
fSUB
fPSC1
TB0[2:0]
P�es�ale� 1
Ti�e Base 1
fH
CLKSEL1[1:0]
TB1[2:0]
fSUB
fSUB
WDT
LVR
Note: The LXT os�illato� is only availa�le fo� BS87C1�A-3 and BS87D20A-3
Device Clock Configurations
Note: When the system clock source fSYS is switched to fSUB from fH, the high speed oscillation will
stop to conserve the power. Thus there is no fH~fH/64 for peripheral circuit to use.
Rev. 1.20
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December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
System Operation Modes
There are five 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 FAST Mode and SLOW Mode. The remaining three modes, the SLEEP, IDLE0
and IDLE1 Mode are used when the microcontroller CPU is switched off to conserve power.
Operation Mode
CPU
fSYS
fSUB
FAST
On
fH~fH/64
On
SLOW
On
fSUB
On
IDLE0
Off
Off
On
IDLE1
Off
On
On
SLEEP
Off
Off
On
FAST 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. The fSUB clock is derived from either the
LIRC or LXT oscillator for BS87C16A-3 and BS87D20A-3 devices while the fSUB clock is from the
LIRC oscillator for the BS87B12A-3 device. Running the microcontroller in this mode allow it to
run with much lower operating currents. In the SLOW Mode, the fH is off.
SLEEP 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 SLEEP mode the CPU will be stopped and both the high and low
speed oscillators will be switched off. However the fSUB clock will continue to operate as the WDT
function is always enabled.
IDLE0 Mode
The IDLE0 Mode is entered when an HALT instruction is executed and when the IDLEN bit in the
SMOD register is high and the FSYSON bit in the CTRL register is low. In the IDLE0 Mode the
system oscillator will be switched off and therefore will be inhibited from driving the CPU and some
peripheral functions.
IDLE1 Mode
The IDLE1 Mode is entered when an HALT instruction is executed and when the IDLEN bit in
the SMOD register is high and the FSYSON bit in the CTRL register is high. In the IDLE1 Mode
the system oscillator will be inhibited from driving the CPU but may continue to provide a clock
source to keep some peripheral functions operational. In the IDLE1 Mode, the system oscillator will
continue to run and this system oscillator may be the high speed or low speed oscillator.
Rev. 1.20
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December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
Control Registers
The register, SMOD, is used to control the internal clocks within the device.
Bit
Register
Name
7
6
5
4
SMOD
CKS2
CKS1
CKS0
—
CTRL
FSYSON
—
HIRCS1
HIRCS0
3
2
1
0
LTO
HTO
IDLEN
HLCLK
LXTLP
LVRF
LRF
WRF
System Operating Mode Control Registers List
SMOD Register
Bit
7
6
5
4
3
2
1
0
Name
CKS2
CKS1
CKS0
—
LTO
HTO
IDLEN
HLCLK
R/W
R/W
R/W
R/W
—
R
R
R/W
R/W
POR
0
0
0
—
0
0
1
1
Bit 7~5
Rev. 1.20
CKS2~CKS0: System clock selection when HLCLK is "0"
000: fSUB (LIRC or LXT)
001: fSUB (LIRC or LXT)
010: fH/64
011: fH/32
100: fH/16
101: fH/8
110: fH/4
111: fH/2
These three bits are used to select which clock is used as the system clock source. In
addition to the system clock source, which can be either the LXT or LIRC, a divided
version of the high speed system oscillator can also be chosen as the system clock
source.
Bit 4
Unimplemented, read as 0.
Bit 3
LTO: Low speed system oscillator ready flag
0: Not ready
1: Ready
This is the low speed system oscillator ready flag which indicates when the low speed
system oscillator is stable after power on reset or a wake-up has occurred. The flag
will be low when in the SLEEP Mode but after a wake-up has occurred, the flag will
change to a high level after 128 clock cycles if LXT oscillator is used and 1~2 clock
cycles if the LIRC oscillator is used.
Bit 2
HTO: High speed system oscillator ready flag
0: Not ready
1: Ready
This is the high speed system oscillator ready flag which indicates when the high
speed system oscillator is stable after a wake-up has occurred. This flag is cleared to
zero by hardware when the device is powered on and then changes to a high level after
the high speed system oscillator is stable. Therefore, this flag will always be read as
"1" by the application program after device power-on. The flag will be low when in
the SLEEP or IDLE0 Mode but after 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.
59
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BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
Bit 1
Bit 0
IDLEN: IDLE Mode Control
0: Disable
1: Enable
This bit 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 the FSYSON bit is low, the CPU and the system clock will all
stop in the IDLE0 Mode. If the bit is low the device will enter the SLEEP Mode when
a HALT instruction is executed.
HLCLK: System clock selection
0: fH/2~ fH/64 or fSUB
1: fH
This bit is used to select if the fH clock, the fH/2~ fH/64 or fSUB clock is used as the
system clock. When this bit is high the fH clock will be selected and if low the fH/2~
fH/64 or fSUB clock will be selected. When the system clock is switched from the fH clock
to the fSUB clock, the fH clock will automatically be switched off to conserve power.
CTRL Register – BS87B12A-3
Bit
7
6
5
4
3
2
1
0
Name
FSYSON
—
HIRCS1
HIRCS0
—
LVRF
LRF
WRF
R/W
R/W
—
R/W
R/W
—
R/W
R/W
R/W
POR
0
—
0
0
—
×
0
0
"×": unknown
CTRL Register – BS87C16A-3 & BS87D20A-3
Bit
7
6
5
4
3
2
1
0
Name
FSYSON
—
HIRCS1
HIRCS0
LXTLP
LVRF
LRF
WRF
R/W
R/W
—
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
—
0
0
0
×
0
Bit 7
Bit 6
Bit 5~4
Bit 3
Bit 2
Bit 1
Bit 0
Rev. 1.20
0
"×": unknown
FSYSON: fSYS Control in IDLE Mode
0: Disable
1: Enable
Unimplemented, read as 0.
HIRCS1~HIRCS0: HIRC frequency clock selection
00: 8 MHz
01: 12 MHz
10: 16 MHz
11: 8 MHz
It is recommended that the HIRC frequency selected by these two bits is the same with
the frequency determined by the configuration option to keep the HIRC frequency
accuracy specified in the A.C. characteristics.
LXTLP: LXT low power control
0: Quick Start mode
1: Low Power mode
Note that this bit is used to selec the operating mode of the LXT oscillator which is
only available for BS87C16A-3 and BS87D20A-3 devices. For the BS87B12A-3
device this bit is unimplemented and is read as "0".
LVRF: LVR function reset flag
Described elsewhere
LRF: LVR control register software reset flag
Described elsewhere
WRF: WDT control register software reset flag
Described elsewhere
60
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
Operating Mode Switching
These devices can switch between operating modes dynamically allowing the user to select the best
performance/power ratio for the present task in hand. In this way microcontroller operations that
do not require high performance can be executed using slower clocks thus requiring less operating
current and prolonging battery life in portable applications.
In simple terms, Mode Switching between the FAST Mode and SLOW Mode is executed using the
HLCLK and CKS2~CKS0 bits in the SMOD register while Mode Switching from the FAST/SLOW
Modes to the SLEEP/IDLE Modes is executed via the HALT instruction. When an 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 the FSYSON bit 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. The accompanying flowchart
shows what happens when the device moves between the various operating modes.
FAST
fSYS=fH~fH/�4
fH on
CPU �un
fSYS on
fSUB on
WDT on
SLEEP
HALT inst�u�tion exe�uted
CPU stop
IDLEN=0
fSYS off� fSUB on
WDT on
IDLE1
HALT inst�u�tion exe�uted
CPU stop
IDLEN=1
FSYSON=1
fSYS on� fSUB on
WDT on
Rev. 1.20
61
SLOW
fSYS=fSUB
fSUB on
CPU �un
fSYS on
fH off
WDT on
IDLE0
HALT inst�u�tion exe�uted
CPU stop
IDLEN=1
FSYSON=0
fSYS off� fSUB on
WDT on
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
FAST Mode to SLOW Mode Switching
When running in the FAST 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 clearing the
HLCLK bit to zero 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 LXT or LIRC oscillator and therefore requires the specific
oscillator to stable before full mode switching occurs.
FAST Mode
CKS2~CKS0 = 00xB &
HLCLK = 0
SLOW Mode
IDLEN=0 & HALT inst�u�tion is exe�uted
SLEEP Mode
IDLEN=1� FSYSON=0
HALT inst�u�tion is exe�uted
IDLE0 Mode
IDLEN=1� FSYSON=1
HALT inst�u�tion is exe�uted
IDLE1 Mode
Rev. 1.20
62
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
SLOW Mode to FAST Mode Switching
In SLOW mode the system uses the fSUB clock derived from either the LXT or LIRC low speed
oscillator as system clock. When system clock is switched back to the FAST mode from fSUB, where
the high speed system oscillator is used, the HLCLK bit should be set high or HLCLK bit is low but
the CKS2~CKS0 bits are set to "010 ~111" and then the system clock will respectively be switched
to fH~ fH/64.
However, if fH is not used in SLOW mode and thus switched off, it will take some time to reoscillate and stabilise when switching back to the FAST mode from the SLOW Mode and the status
of the HTO flag should be checked. The time duration required for the high speed system oscillator
stabilization is specified in the relevant characteristics.
SLOW Mode
CKS2~CKS0≠00xB & as HLCLK=0
o� HLCLK = 1
FAST Mode
IDLEN=0 & HALT inst�u�tion is exe�uted
SLEEP Mode
IDLEN=1� FSYSON=0
HALT inst�u�tion is exe�uted
IDLE0 Mode
IDLEN=1� FSYSON=1
HALT inst�u�tion is exe�uted
IDLE1 Mode
Entering the SLEEP Mode
There is only one way for the device to enter the SLEEP Mode and that is to execute the "HALT"
instruction in the application program with the IDLEN bit in the SMOD register equal to "0". In
this mode all the clocks and functions will be switched off except the WDT function. 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.
• The Data Memory contents and registers will maintain their present condition.
• The I/O ports will maintain their present conditions.
• In the status register, the Power Down flag PDF will be set, and WDT timeout flag TO will be
cleared.
• The WDT will be cleared and resume counting as the WDT function is always enabled.
Rev. 1.20
63
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
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 the SMOD register equal to "1" and
the FSYSON bit in the 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 clock fSUB will be on.
• The Data Memory contents and registers will maintain their present condition.
• The I/O ports will maintain their present conditions.
• In the status register, the Power Down flag PDF will be set, and WDT timeout flag TO will be
cleared.
• The WDT will be cleared and resume counting.
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 the SMOD register is equal to "1"
and the FSYSON bit in the CTRL register equal to "1". When this instruction is executed under the
conditions described above, the following will occur:
• The system and the low frequency fSUB clocks will be on but the application program will stop at
the "HALT" instruction.
• The Data Memory contents and registers will maintain their present condition.
• The I/O ports will maintain their present conditions.
• In the status register, the Power Down flag PDF will be set, and WDT timeout flag TO will be
cleared.
• The WDT will be cleared and resume counting.
Standby Current Considerations
As the main reason for entering the SLEEP or IDLE Mode is to keep the current consumption of the
device to as low a value as possible, perhaps only in the order of several micro-amps except in the
IDLE1 Mode, there are other considerations which must also be taken into account by the circuit
designer if the power consumption is to be minimised. Special attention must be made to the I/O pins
on the device. All high-impedance input pins must be connected to either a fixed high or low level as
any floating input pins could create internal oscillations and result in increased current consumption.
This also applies to devices which have different package types, as there may be unbonded pins.
These must either be setup as outputs or if setup as inputs must have pull-high resistors connected.
Care must also be taken with the loads, which are connected to I/O pins, which are setup as outputs.
These should be placed in a condition in which minimum current is drawn or connected only to
external circuits that do not draw current, such as other CMOS inputs. Also note that additional
standby current will also be consumed if the LIRC oscillator has enabled.
In the IDLE1 Mode the system oscillator is on, if the peripheral function clock source is derived
from the high speed oscillator, the additional standby current will also be perhaps in the order of
several hundred micro-amps.
Rev. 1.20
64
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
Wake-up
To minimise power consumption the device can enter the SLEEP or any IDLE Mode, where the
CPU will be switched off. However, when the device is woken up again, it will take a considerable
time for the original system oscillator to restart, stabilise and allow normal operation to resume.
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
When the device executes the "HALT" instruction, the PDF flag will be set to 1. The PDF flag will
be cleared to 0 if the device experiences a system power-up or executes the clear Watchdog Timer
instruction. If the system is woken up by a WDT overflow, a Watchdog Timer reset will be initiated
and the TO flag will be set to 1. The TO flag is set if a WDT time-out occurs and causes a wake-up
that only resets the Program Counter and Stack Pointer, 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.
System Oscillator
Wake-up Time
(SLEEP Mode)
Wake-up Time
(IDLE0 Mode)
Wake-up Time
(IDLE1 Mode)
HIRC
15~16 HIRC cycles
1~2 HIRC cycles
LIRC
1~2 LIRC cycles
1~2 LIRC cycles
LXT*
128 LXT cycles
1~2 LXT cycles
Note: The LXT oscillator is only available for the BS87C16A-3 and BS87D20A-3 devices.
Wake-up Time
Programming Considerations
The high speed and low speed oscillators both use the same SST counter. For example, if the system
is woken up from the SLEEP Mode the HIRC oscillator needs to start-up from an off state. If the
device is woken up from the SLEEP Mode to the FAST Mode, the high speed system oscillator
needs an SST period. The device will execute the first instruction after HTO is high. At this time, the
LXT oscillator may not be stability if fSUB is from LXT oscillator. The same situation occurs in the
power-on state. The LXT oscillator is not ready yet when the first instruction is executed.
Rev. 1.20
65
December 05, 2016
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Touch A/D Flash MCU with OCVP
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 fSUB clock shich is in turn supplied by
either the LXT or LIRC oscillator selected by a configuration option. The LIRC internal oscillator
has an approximate frequency of 32 kHz and this specified internal clock period can vary with
VDD, temperature and process variations. The LXT oscillator is supplied by an external 32.768 kHz
crystal. 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.
Watchdog Timer Control Register
A single register, WDTC, controls the required timeout period as well as the enable control. This
register controls the overall operation of the Watchdog Timer. The WDTC register is initiated to
01010011B at any reset except the WDT time-out hardware warm reset.
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 7~3
WE4~WE0: WDT function control
01010 or 10101: Enabled
Other values: Reset MCU
If these bits are changed due to adverse environmental conditions, the microcontroller
will be reset. The reset operation will be activated after a delay time, tSRESET, and the
WRF bit in the RSTFC register will be set to 1.
Bit 2~0
WS2~WS0: WDT time-out period selection
000: 28/fSUB
001: 210/fSUB
010: 212/fSUB
011: 214/fSUB
100: 215/fSUB
101: 216/fSUB
110: 217/fSUB
111: 218/fSUB
These three bits determine the division ratio of the watchdog timer source clock,
which in turn determines the time-out period.
CTRL Register
Bit
7
6
5
4
3
2
1
0
Name
FSYSON
—
HIRCS1
HIRCS0
LXTLP
LVRF
LRF
WRF
R/W
R/W
—
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
—
0
0
0
×
0
0
Bit 7
Bit 6
Bit 5~4
Rev. 1.20
FSYSON: fSYS Control in IDLE Mode
Described elsewhere
Unimplemented, read as 0.
HIRCS1~HIRCS0: HIRC frequency clock selection
Described elsewhere
66
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December 05, 2016
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Bit 3
LXTLP: LXT low power control
Described elsewhere
Bit 2
LVRF: LVR function reset flag
Described elsewhere
Bit 1
LRF: LVR control register software reset flag
Described elsewhere
Bit 0
WRF: WDT control register software reset flag
0: Not 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 instruction. If the program malfunctions for whatever reason,
jumps to an unknown location, or enters an endless loop, the clear instruction 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 five bits, WE4~WE0, in the WDTC
register to offer the enable and reset control of the Watchdog Timer. The WDT function will be
enabled when the WE4~WE0 bits are set to a value of 01010B or 10101B. If the WE4~WE0 bits are
changed to any other values rather than 01010B and 10101B, which is caused by the environmental
noise, it will reset the device after a delay time, tSRESET. After power on these bits will have a value of
01010B.
WE4 ~ WE0 Bits
WDT Function
10101B or 01010B
Enable
Any other value
Reset MCU
Watchdog Timer Enable/Reset Control
Under normal program operation, a Watchdog Timer time-out will initialise a device reset and set
the status bit TO. However, if the system is in the SLEEP or IDLE Mode, when a Watchdog Timer
time-out occurs, the TO bit in the status register will be set and only the Program Counter and Stack
Pointer will be reset. Three methods can be adopted to clear the contents of the Watchdog Timer.
The first is a WDT reset, which means a certain value except 01010B and 10101B written into the
WE4~WE0 field, the second is using the Watchdog Timer software clear instruction 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 contents.
The maximum time out period is when the 218 division ratio is selected. As an example, with a 32
kHz 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 8ms for the 28 division ration.
Rev. 1.20
67
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
WDTC WE4~WE0 bits
Register
Reset MCU
CLR
“HALT”Instruction
“CLR WDT”Instruction
LIRC
fSUB
LXT*
Configuration
option
8-stage Divider
fSUB/28
WDT Prescaler
8-to-1 MUX
WS2~WS0
(fSUB/28 ~ fSUB/218)
WDT Time-out
(28/fSUB ~ 218/fSUB)
Note: The LXT oscillator is only available for BS87C16A-3 and BS87D20A-3
Watchdog timer
Reset and Initialisation
A reset function is a fundamental part of any microcontroller ensuring that the device can be set
to some predetermined condition irrespective of outside parameters. The most important reset
condition is after power is first applied to the microcontroller. In this case, internal circuitry will
ensure that the microcontroller, after a short delay, will be in a well defined state and ready to
execute the first program instruction. After this power-on reset, certain important internal registers
will be set to defined states before the program commences. One of these registers is the Program
Counter, which will be reset to zero forcing the microcontroller to begin program execution from the
lowest Program Memory address.
The Watchdog Timer overflow is one of many reset types and will reset the microcontroller. Another
reset exists in the form of a Low Voltage Reset, LVR, where a full reset implemented in situations
where the power supply voltage falls below a certain threshold. All types of reset operations result in
different register conditions being setup.
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
Note: tRSTD is power-on delay with typical time=50 ms
Power-On Reset Timing Chart
Rev. 1.20
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Low Voltage Reset – LVR
The microcontroller contains a low voltage reset circuit in order to monitor the supply voltage of the
device. The LVR function is always enabled with a specific LVR voltage, VLVR. If the supply voltage
of the device drops to within a range of 0.9V~VLVR such as might occur when changing the battery,
the LVR will automatically reset the device internally and the LVRF bit in the CTRL register will
also be set to 1. For a valid LVR signal, a low supply voltage, i.e., a voltage in the range between
0.9V~VLVR must exist for a time greater than that specified by tLVR in the LVD/LVR characteristics. If
the low supply voltage state does not exceed this value, the LVR will ignore the low supply voltage
and will not perform a reset function. The actual VLVR value is fixed at a voltage value of 2.55V by
the LVS bits in the LVRC register. If the LVS7~LVS0 bits have any other value, which may perhaps
occur due to adverse environmental conditions such as noise, the LVR will reset the device after
a delay time, tSRESET. When this happens, the LRF bit in the CTRL register will be set to 1. After
power on the register will have the default value of 01010101B. Note that the LVR function will be
automatically disabled when the device enters the SLEEP/IDLE mode.
LVR
tRSTD + tSST
Internal Reset
Note: tRSTD is power-on delay with typical time=50 ms
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
Rev. 1.20
LVS7~LVS0: LVR voltage select
01010101: 2.55V
00110011: 2.55V
10011001: 2.55V
10101010: 2.55V
Other values: Generates a MCU reset – register is reset to POR value
When an actual low voltage condition occurs, as specified by the LVR voltage value
above, an MCU reset will be generated. The reset operation will be activated after the
low voltage condition keeps for greater than a tLVR time. In this situation the register
contents will remain the same after such a reset occurs.
Any register value, other than the four defined register 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 the register contents will be reset to the POR
value.
69
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
• CTRL Register
Bit
7
6
5
4
3
2
1
0
Name
FSYSON
—
HIRCS1
HIRCS0
LXTLP
LVRF
LRF
WRF
R/W
R/W
—
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
—
0
0
0
×
0
0
"×": unknown
Bit 7
FSYSON: fSYS Control in IDLE Mode
Described elsewhere
Bit 6
Unimplemented, read as 0.
Bit 5~4
HIRCS1~HIRCS0: HIRC frequency clock selection
Described elsewhere
Bit 3
LXTLP: LXT low power control
Described elsewhere
Bit 2
LVRF: LVR function reset flag
0: Not occurred
1: Occurred
This bit is set to 1 when a specific low voltage reset condition occurs. Note that this bit
can only be cleared to 0 by the application program.
Bit 1
LRF: LVR control register software reset flag
0: Not occurred
1: Occurred
This bit is set to 1 by the LVRC control register contains any undefined LVR voltage
register values. This in effect acts like a software-reset function. Note that this bit can
only be cleared to 0 by the application program.
Bit 0
WRF: WDT control register software reset flag
Described elsewhere.
Watchdog Time-out Reset during Normal Operation
The Watchdog time-out Reset during normal operation is the same as the hardware Low Voltage
Reset except that the Watchdog time-out flag TO will be set to "1".
WDT Time-out
tRSTD + tSST
Internal Reset
Note: tRSTD is power-on delay with typical time=16.7 ms
WDT Time-out Reset during NORMAL Operation Timing Chart
Watchdog Time-out Reset during SLEEP or IDLE Mode
The Watchdog time-out Reset during SLEEP or IDLE Mode is a little different from other kinds
of reset. Most of the conditions remain unchanged except that the Program Counter and the Stack
Pointer will be cleared to "0" and the TO flag will be set to "1". Refer to the A.C. Characteristics for
tSST details.
WDT Time-out
tSST
Internal Reset
WDT Time-out Reset during SLEEP or IDLE Mode Timing Chart
Rev. 1.20
70
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
Reset Initial Conditions
The different types of reset described affect the reset flags in different ways. These flags, known
as PDF and TO are located in the status register and are controlled by various microcontroller
operations, such as the SLEEP or IDLE Mode function or Watchdog Timer. The reset flags are
shown in the table:
TO
PDF
Reset Function
0
0
Power-on reset
u
u
LVR reset during NORMAL or SLOW Mode operation
1
u
WDT time-out reset during NORMAL or SLOW Mode operation
1
1
WDT time-out reset during IDLE or SLEEP Mode operation
"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
Reset Function
Program Counter
Reset to zero
Interrupts
All interrupts will be disabled
WDT, Time Base
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
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 the microcontroller internal registers.
BS87B12A-3
BS87C16A-3
BS87D20A-3
Power On Reset
IAR0
●
●
●
0000 0000
0000 0000
0000 0000
uuuu uuuu
MP0
●
●
●
0000 0000
0000 0000
0000 0000
uuuu uuuu
IAR1
●
●
●
0000 0000
0000 0000
0000 0000
uuuu uuuu
MP1L
●
●
●
0000 0000
0000 0000
0000 0000
uuuu uuuu
MP1H
●
●
●
0000 0000
0000 0000
0000 0000
uuuu uuuu
ACC
●
●
●
xxxx xxxx
uuuu uuuu
uuuu uuuu
uuuu uuuu
PCL
●
●
●
0000 0000
0000 0000
0000 0000
0000 0000
TBLP
●
●
●
xxxx xxxx
uuuu uuuu
uuuu uuuu
uuuu uuuu
TBLH
●
●
●
xxxx xxxx
uuuu uuuu
uuuu uuuu
uuuu uuuu
TBHP
●
●
---- xxxx
---- uuuu
---- uuuu
---- uuuu
●
---x xxxx
---u uuuu
---u uuuu
---u uuuu
Register
TBHP
LVR Reset
(Normal
Operation)
WDT Time-out
(Normal
Operation)
WDT Time-out
(IDLE/SLEEP)*
STATUS
●
●
●
xx00 xxxx
uuuu uuuu
xx1u uuuu
u u 11 u u u u
SMOD
●
●
●
0 0 0 - 0 0 11
0 0 0 - 0 0 11
0 0 0 - 0 0 11
uuu- uuuu
IAR2
●
●
●
xxxx xxxx
uuuu uuuu
uuuu uuuu
uuuu uuuu
MP2L
●
●
●
0000 0000
0000 0000
0000 0000
uuuu uuuu
MP2H
●
●
●
0000 0000
0000 0000
0000 0000
uuuu uuuu
INTEG
●
●
●
---- --00
---- --00
---- --00
---- --uu
Rev. 1.20
71
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
BS87B12A-3
BS87C16A-3
BS87D20A-3
Power On Reset
INTC0
●
●
●
-000 0000
-000 0000
-000 0000
-uuu uuuu
INTC1
●
●
●
0000 0000
0000 0000
0000 0000
uuuu uuuu
INTC2
●
000- 000-
000- 000-
000- 000-
uuu- uuu-
Register
INTC2
LVR Reset
(Normal
Operation)
WDT Time-out
(Normal
Operation)
WDT Time-out
(IDLE/SLEEP)*
●
●
0000 0000
0000 0000
0000 0000
uuuu uuuu
INTC3
●
●
●
0000 0000
0000 0000
0000 0000
uuuu uuuu
PA
●
●
●
1 - - 1 1111
1 - - 1 1111
1 - - 1 1111
u--u uuuu
PAC
●
●
●
1 - - 1 1111
1 - - 1 1111
1 - - 1 1111
u--u uuuu
PAPU
●
●
●
0--0 0000
0--0 0000
0--0 0000
u--u uuuu
PAWU
●
●
●
0--0 0000
0--0 0000
0--0 0000
u--u uuuu
PB
●
●
●
1111 1111
1111 1111
1111 1111
uuuu uuuu
PBC
●
●
●
1111 1111
1111 1111
1111 1111
uuuu uuuu
PBPU
●
●
●
0000 0000
0000 0000
0000 0000
uuuu uuuu
PC
●
●
●
1111 1111
1111 1111
1111 1111
uuuu uuuu
PCC
●
●
●
1111 1111
1111 1111
1111 1111
uuuu uuuu
PCPU
●
●
●
0000 0000
0000 0000
0000 0000
uuuu uuuu
PD
●
●
1111 1111
1111 1111
1111 1111
uuuu uuuu
PDC
●
●
1111 1111
1111 1111
1111 1111
uuuu uuuu
PDPU
●
●
0000 0000
0000 0000
0000 0000
uuuu uuuu
PE
●
1111 1111
1111 1111
1111 1111
uuuu uuuu
PEC
●
1111 1111
1111 1111
1111 1111
uuuu uuuu
PEPU
●
0000 0000
0000 0000
0000 0000
uuuu uuuu
PF
●
- - - - 1111
- - - - 1111
- - - - 1111
---- uuuu
PFC
●
- - - - 1111
- - - - 1111
- - - - 1111
---- uuuu
PFPU
●
---- 0000
---- 0000
---- 0000
---- uuuu
●
0101 0101
0101 0101
0101 0101
uuuu uuuu
---- 0101
---- 0101
---- 0101
---- uuuu
●
0101 0101
0101 0101
0101 0101
uuuu uuuu
●
--01 0101
--01 0101
--01 0101
--uu uuuu
SLEDC0
●
SLEDC1
●
SLEDC1
●
●
SLEDC2
WDTC
●
●
●
0 1 0 1 0 0 11
0 1 0 1 0 0 11
0 1 0 1 0 0 11
uuuu uuuu
TBC
●
●
●
0000 0000
0000 0000
0000 0000
uuuu uuuu
PSCR
●
●
●
--00 --00
--00 --00
--00 --00
--uu --uu
LVRC
●
●
●
0101 0101
0101 0101
0101 0101
uuuu uuuu
EEA
●
●
●
--00 0000
--00 0000
--00 0000
--uu uuuu
EED
●
●
●
0000 0000
0000 0000
0000 0000
uuuu uuuu
SIMTOC
●
●
●
0000 0000
0000 0000
0000 0000
uuuu uuuu
SIMC0
●
●
●
111 - 0 0 0 0
111 - 0 0 0 0
111 - 0 0 0 0
uuu- uuuu
SIMC1
●
●
●
1000 0001
1000 0001
1000 0001
uuuu uuuu
SIMD
●
●
●
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
SIMA/SIMC2
●
●
●
0000 0000
0000 0000
0000 0000
uuuu uuuu
USR
●
●
●
0 0 0 0 1 0 11
0 0 0 0 1 0 11
0 0 0 0 1 0 11
uuuu uuuu
UCR1
●
●
●
0000 00x0
0000 00x0
0000 00x0
uuuu uuuu
UCR2
●
●
●
0000 0000
0000 0000
0000 0000
uuuu uuuu
BRG
●
●
●
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
TXR_RXR
●
●
●
xxxx xxxx
xxxx xxxx
xxxx xxxx
uuuu uuuu
Rev. 1.20
72
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
●
BS87D20A-3
●
BS87C16A-3
SADOL
BS87B12A-3
Register
●
Power On Reset
xxxx ----
LVR Reset
(Normal
Operation)
xxxx ----
WDT Time-out
(Normal
Operation)
xxxx ----
WDT Time-out
(IDLE/SLEEP)*
uuuu ---(ADRFS=0)
uuuu uuuu
(ADRFS=1)
uuuu uuuu
(ADRFS=0)
SADOH
●
●
●
xxxx xxxx
uuuu uuuu
uuuu uuuu
SADC0
●
●
●
0000 0000
0000 0000
0000 0000
uuuu uuuu
SADC1
●
●
●
0000 0000
0000 0000
0000 0000
uuuu uuuu
ACERL
●
●
●
0000 0000
0000 0000
0000 0000
uuuu uuuu
TMPC0
●
0--- 0000
0--- 0000
0--- 0000
u--- uuuu
●
0-00 0000
0-00 0000
0-00 0000
u-uu uuuu
●
---- --00
---- --00
---- --00
---- --uu
TMPC0
●
TMPC1
---- uuuu
(ADRFS=1)
SLCDC0
●
●
●
0000 0000
0000 0000
0000 0000
uuuu uuuu
SLCDC1
●
●
●
0000 0000
0000 0000
0000 0000
uuuu uuuu
SLCDC2
●
●
●
0000 0000
0000 0000
0000 0000
uuuu uuuu
---- 0000
---- 0000
---- 0000
---- uuuu
uuuu uuuu
SLCDC3
●
SLCDC3
●
0000 0000
0000 0000
0000 0000
SLCDC4
●
0000 0000
0000 0000
0000 0000
uuuu uuuu
SLCDC5
●
---- 0000
---- 0000
---- 0000
---- uuuu
LVDC
●
●
●
--00 0000
--00 0000
--00 0000
--uu uuuu
OCVPC0
●
●
●
11 0 0 1 0 0 0
11 0 0 1 0 0 0
11 0 0 1 0 0 0
uuuu uuuu
IFS
●
---- 0000
---- 0000
---- 0000
---- uuuu
--00 --00
--00 --00
--00 --00
--uu --uu
0000 0000
0000 0000
0000 0000
uuuu uuuu
0-00 -x00
0-00 -x00
0-00 -x00
u-uu -uuu
MFI
●
MFI
CTRL
●
●
CTRL
●
●
0-00 0x00
---- u1uu
---- uuuu
---- uuuu
OCVPC1
●
●
●
0000 --00
0000 --00
0000 --00
uuuu --uu
OCVPC2
●
●
●
-000 0000
-000 0000
-000 0000
-uuu uuuu
OCVPC3
●
●
●
0000 --00
0000 --00
0000 --00
uuuu --uu
TKTMR
●
●
●
0000 0000
0000 0000
0000 0000
uuuu uuuu
TKC0
●
●
●
-000 0000
-000 0000
-000 0000
-uuu uuuu
TK16DL
●
●
●
0000 0000
0000 0000
0000 0000
uuuu uuuu
TK16DH
●
●
●
0000 0000
0000 0000
0000 0000
uuuu uuuu
TKC1
●
●
●
---- --11
---- --11
---- --11
---- --uu
TKM016DL
●
●
●
0000 0000
0000 0000
0000 0000
uuuu uuuu
TKM016DH
●
●
●
0000 0000
0000 0000
0000 0000
uuuu uuuu
TKM0ROL
●
●
●
0000 0000
0000 0000
0000 0000
uuuu uuuu
TKM0ROH
●
●
●
---- --00
---- --00
---- --00
---- --uu
TKM0C0
●
●
●
0000 0000
0000 0000
0000 0000
uuuu uuuu
TKM0C1
●
●
●
0-00 0000
0-00 0000
0-00 0000
u-uu uuuu
TKM116DL
●
●
●
0000 0000
0000 0000
0000 0000
uuuu uuuu
TKM116DH
●
●
●
0000 0000
0000 0000
0000 0000
uuuu uuuu
TKM1ROL
●
●
●
0000 0000
0000 0000
0000 0000
uuuu uuuu
Rev. 1.20
73
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
BS87B12A-3
BS87C16A-3
BS87D20A-3
Power On Reset
TKM1ROH
●
●
●
---- --00
---- --00
---- --00
---- --uu
TKM1C0
●
●
●
0000 0000
0000 0000
0000 0000
uuuu uuuu
TKM1C1
●
●
●
0-00 0000
0-00 0000
0-00 0000
u-uu uuuu
TKM216DL
●
●
●
0000 0000
0000 0000
0000 0000
uuuu uuuu
TKM216DH
●
●
●
0000 0000
0000 0000
0000 0000
uuuu uuuu
TKM2ROL
●
●
●
0000 0000
0000 0000
0000 0000
uuuu uuuu
TKM2ROH
●
●
●
---- --00
---- --00
---- --00
---- --uu
TKM2C0
●
●
●
0000 0000
0000 0000
0000 0000
uuuu uuuu
TKM2C1
●
●
●
0-00 0000
0-00 0000
0-00 0000
u-uu uuuu
TKM316DL
●
●
0000 0000
0000 0000
0000 0000
uuuu uuuu
TKM316DH
●
●
0000 0000
0000 0000
0000 0000
uuuu uuuu
TKM3ROL
●
●
0000 0000
0000 0000
0000 0000
uuuu uuuu
TKM3ROH
●
●
---- --00
---- --00
---- --00
---- --uu
TKM3C0
●
●
0000 0000
0000 0000
0000 0000
uuuu uuuu
TKM3C1
●
●
0-00 0000
0-00 0000
0-00 0000
u-uu uuuu
TKM416DL
●
0000 0000
0000 0000
0000 0000
uuuu uuuu
TKM416DH
●
0000 0000
0000 0000
0000 0000
uuuu uuuu
TKM4ROL
●
0000 0000
0000 0000
0000 0000
uuuu uuuu
TKM4ROH
●
---- --00
---- --00
---- --00
---- --uu
TKM4C0
●
0000 0000
0000 0000
0000 0000
uuuu uuuu
Register
TKM4C1
LVR Reset
(Normal
Operation)
WDT Time-out
(Normal
Operation)
WDT Time-out
(IDLE/SLEEP)*
●
0-00 0000
0-00 0000
0-00 0000
u-uu uuuu
CTM0C0
●
●
●
0000 0000
0000 0000
0000 0000
uuuu uuuu
CTM0C1
●
●
●
0000 0000
0000 0000
0000 0000
uuuu uuuu
CTM0DL
●
●
●
0000 0000
0000 0000
0000 0000
uuuu uuuu
CTM0DH
●
●
●
---- --00
---- --00
---- --00
---- --uu
CTM0AL
●
●
●
0000 0000
0000 0000
0000 0000
uuuu uuuu
CTM0AH
●
●
●
---- --00
---- --00
---- --00
---- --uu
PTM0C0
●
●
●
0000 0---
0000 0---
0000 0---
uuuu u---
PTM0C1
●
●
●
0000 0000
0000 0000
0000 0000
uuuu uuuu
PTM0DL
●
●
●
0000 0000
0000 0000
0000 0000
uuuu uuuu
PTM0DH
●
●
●
---- --00
---- --00
---- --00
---- --uu
PTM0AL
●
●
●
0000 0000
0000 0000
0000 0000
uuuu uuuu
PTM0AH
●
●
●
---- --00
---- --00
---- --00
---- --uu
PTM0RPL
●
●
●
0000 0000
0000 0000
0000 0000
uuuu uuuu
PTM0RPH
●
●
●
---- --00
---- --00
---- --00
---- --uu
PTM1C0
●
●
0000 0---
0000 0---
0000 0---
uuuu u---
PTM1C1
●
●
0000 0000
0000 0000
0000 0000
uuuu uuuu
PTM1DL
●
●
0000 0000
0000 0000
0000 0000
uuuu uuuu
PTM1DH
●
●
---- --00
---- --00
---- --00
---- --uu
PTM1AL
●
●
0000 0000
0000 0000
0000 0000
uuuu uuuu
PTM1AH
●
●
---- --00
---- --00
---- --00
---- --uu
PTM1RPL
●
●
0000 0000
0000 0000
0000 0000
uuuu uuuu
PTM1RPH
●
●
---- --00
---- --00
---- --00
---- --uu
●
0000 0000
0000 0000
0000 0000
uuuu uuuu
CTM1C0
Rev. 1.20
74
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
BS87D20A-3
BS87C16A-3
BS87B12A-3
Register
Power On Reset
LVR Reset
(Normal
Operation)
WDT Time-out
(Normal
Operation)
WDT Time-out
(IDLE/SLEEP)*
uuuu uuuu
CTM1C1
●
0000 0000
0000 0000
0000 0000
CTM1DL
●
0000 0000
0000 0000
0000 0000
uuuu uuuu
CTM1DH
●
---- --00
---- --00
---- --00
---- --uu
CTM1AL
●
0000 0000
0000 0000
0000 0000
uuuu uuuu
CTM1AH
●
---- --00
---- --00
---- --00
---- --uu
OCVPDA
●
●
●
0000 0000
0000 0000
0000 0000
uuuu uuuu
OCVPOCAL
●
●
●
0010 0000
0010 0000
0010 0000
uuuu uuuu
OCVPCCAL
●
●
●
0001 0000
0001 0000
0001 0000
uuuu uuuu
EEC
●
●
●
---- 0000
---- 0000
---- 0000
---- uuuu
Note: "u" stands for unchanged
"x" stands for "unknown"
"-" stands for unimplemented
Rev. 1.20
75
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
Input/Output Ports
Holtek microcontrollers offer considerable flexibility on their I/O ports. With the input or output
designation of every pin fully under user program control, pull-high selections for all ports and
wake-up selections on certain pins, the user is provided with an I/O structure to meet the needs of a
wide range of application possibilities.
These devices provide bidirectional input/output lines. 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.
Register
Name
Bit
7
6
5
4
3
2
1
0
PA
PA7
—
—
PA4
PA3
PA2
PA1
PA0
PAC
PAC7
—
—
PAC4
PAC3
PAC2
PAC1
PAC0
PAPU
PAPU7
—
—
PAPU4
PAPU3
PAPU2
PAPU1
PAPU0
PAWU
PAWU7
—
—
PAWU4
PAWU3
PAWU2
PAWU1
PAWU0
PB
PB7
PB6
PB5
PB4
PB3
PB2
PB1
PB0
PBC
PBC7
PBC6
PBC5
PBC4
PBC3
PBC2
PBC1
PBC0
PBPU3
PBPU2
PBPU1
PBPU0
PBPU
PBPU7 PBPU6 PBPU5 PBPU4
PC
PC7
PC6
PC5
PC4
PC3
PC2
PC1
PC0
PCC
PCC7
PCC6
PCC5
PCC4
PCC3
PCC2
PCC1
PCC0
PCPU2
PCPU1
PCPU0
PCPU
IFS
PCPU7 PCPU6 PCPU5 PCPU4
—
—
—
—
PCPU3
CTP0BPS
CTP0PS OCVPAI2PS OCVPAI1PS
"—": Unimplemented, read as "0".
I/O Logic Function Registers List – BS87B12A-3
Bit
Register
Name
7
6
5
4
3
2
1
0
PA
PA7
—
—
PA4
PA3
PA2
PA1
PA0
PAC
PAC7
—
—
PAC4
PAC3
PAC2
PAC1
PAC0
PAPU
PAPU7
—
—
PAPU4
PAPU3
PAPU2
PAPU1
PAPU0
PAWU
PAWU7
—
—
PAWU4
PAWU3
PAWU2
PAWU1
PAWU0
PB
PB7
PB6
PB5
PB4
PB3
PB2
PB1
PB0
PBC
PBC7
PBC6
PBC5
PBC4
PBC3
PBC2
PBC1
PBC0
PBPU
PBPU7
PBPU6
PBPU5
PBPU4
PBPU3
PBPU2
PBPU1
PBPU0
PC
PC7
PC6
PC5
PC4
PC3
PC2
PC1
PC0
PCC
PCC7
PCC6
PCC5
PCC4
PCC3
PCC2
PCC1
PCC0
PCPU
PCPU7
PCPU6
PCPU5
PCPU4
PCPU3
PCPU2
PCPU1
PCPU0
PD
PD7
PD6
PD5
PD4
PD3
PD2
PD1
PD0
PDC
PDC7
PDC6
PDC5
PDC4
PDC3
PDC2
PDC1
PDC0
PDPU
PDPU7
PDPU6
PDPU5
PDPU4
PDPU3
PDPU2
PDPU1
PDPU0
"—": Unimplemented, read as "0".
I/O Logic Function Registers List – BS87C16A-3
Rev. 1.20
76
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
Bit
Register
Name
7
6
5
4
3
2
1
0
PA
PA7
—
—
PA4
PA3
PA2
PA1
PA0
PAC
PAC7
—
—
PAC4
PAC3
PAC2
PAC1
PAC0
PAPU
PAPU7
—
—
PAPU4
PAPU3
PAPU2
PAPU1
PAPU0
PAWU
PAWU7
—
—
PAWU4
PAWU3
PAWU2
PAWU1
PAWU0
PB
PB7
PB6
PB5
PB4
PB3
PB2
PB1
PB0
PBC
PBC7
PBC6
PBC5
PBC4
PBC3
PBC2
PBC1
PBC0
PBPU
PBPU7
PBPU6
PBPU5
PBPU4
PBPU3
PBPU2
PBPU1
PBPU0
PC
PC7
PC6
PC5
PC4
PC3
PC2
PC1
PC0
PCC
PCC7
PCC6
PCC5
PCC4
PCC3
PCC2
PCC1
PCC0
PCPU
PCPU7
PCPU6
PCPU5
PCPU4
PCPU3
PCPU2
PCPU1
PCPU0
PD
PD7
PD6
PD5
PD4
PD3
PD2
PD1
PD0
PDC
PDC7
PDC6
PDC5
PDC4
PDC3
PDC2
PDC1
PDC0
PDPU
PDPU7
PDPU6
PDPU5
PDPU4
PDPU3
PDPU2
PDPU1
PDPU0
PE
PE7
PE6
PE5
PE4
PE3
PE2
PE1
PE0
PEC
PEC7
PEC6
PEC5
PEC4
PEC3
PEC2
PEC1
PEC0
PEPU
PEPU7
PEPU6
PEPU5
PEPU4
PEPU3
PEPU2
PEPU1
PEPU0
PF
—
—
—
—
PF3
PF2
PF1
PF0
PFC
—
—
—
—
PFC3
PFC2
PFC1
PFC0
PFPU
—
—
—
—
PFPU3
PFPU2
PFPU1
PFPU0
"—": Unimplemented, read as "0".
I/O Logic Function Registers List – BS87D20A-3
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 the relevant pull-high control registers and are implemented
using weak PMOS transistors.
PxPU Register
Bit
7
6
5
4
3
2
1
0
Name
PxPU7
PxPU6
PxPU5
PxPU4
PxPU3
PxPU2
PxPU1
PxPU0
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
PxPUn: I/O Port x Pin pull-high function control
0: Disable
1: Enable
The PxPUn bit is used to control the pin pull-high function. Here the "x" is the Port name which can
be A, B, C, D, E and F depending upon the selected device. However, the actual available bits for
each I/O Port may be different.
Rev. 1.20
77
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
Port A Wake-up
The HALT instruction forces the microcontroller into the SLEEP or IDLE Mode which preserves
power, a feature that is important for battery and other low-power applications. Various methods
exist to wake-up the microcontroller, one of which is to change the logic condition on one of the Port
A pins from high to low. This function is especially suitable for applications that can be woken up
via external switches. Each pin on Port A can be selected individually to have this wake-up feature
using the PAWU register.
PAWU Register
Bit
7
6
5
4
3
2
1
0
Name
PAWU7
—
—
PAWU4
PAWU3
PAWU2
PAWU1
PAWU0
R/W
R/W
—
—
R/W
R/W
R/W
R/W
R/W
POR
0
—
—
0
0
0
0
0
Bit 7, 4~0
PAWU7, PAWU4~PAWU0: Port A pin Wake-up function control
0: Disable
1: Enable
Bit 6~5
Unimplemented, read as 0.
I/O Port Control Registers
Each Port has its own control register which controls the input/output configuration. With this
control register, each I/O pin with or without pull-high resistors can be reconfigured dynamically
under software control. 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.
PxC Register
Bit
7
6
5
4
3
2
1
0
Name
PxC7
PxC6
PxC5
PxC4
PxC3
PxC2
PxC1
PxC0
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
PxCn: I/O Port x Pin type selection
0: Output
1: Input
The PxCn bit is used to control the pin type selection. Here the "x" is the Port name which can be A,
B, C, D, E and F depending upon the selected device. However, the actual available bits for each I/O
Port may be different.
Rev. 1.20
78
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
I/O Port Source Current Selection
These devices support different output source current driving capability for each I/O port. With the
selection register, SLEDCn, specific I/O port can support four levels of the source current driving
capability. Users should refer to the I/O Port characteristics section to select the desired output
source current for different applications.
Bit
Register
Name
7
6
5
4
3
2
1
0
SLEDC0
PBPS3
PBPS2
PBPS1
PBPS0
PAPS3
PAPS2
PAPS1
PAPS0
SLEDC1
—
—
—
—
PCPS3
PCPS2
PCPS1
PCPS0
I/O Port Source Current Selection Registers List – BS87B12A-3
Bit
Register
Name
7
6
5
4
3
2
1
0
SLEDC0
PBPS3
PBPS2
PBPS1
PBPS0
PAPS3
PAPS2
PAPS1
PAPS0
SLEDC1
PDPS3
PDPS2
PDPS1
PDPS0
PCPS3
PCPS2
PCPS1
PCPS0
I/O Port Source Current Selection Registers List – BS87C16A-3
Bit
Register
Name
7
6
5
4
3
2
1
0
SLEDC0
PBPS3
PBPS2
PBPS1
PBPS0
PAPS3
PAPS2
PAPS1
PAPS0
SLEDC1
PDPS3
PDPS2
PDPS1
PDPS0
PCPS3
PCPS2
PCPS1
PCPS0
SLEDC2
—
—
PFPS1
PFPS0
PEPS3
PEPS2
PEPS1
PEPS0
I/O Port Source Current Selection Registers List – BS87D20A-3
SLEDC0 Register
Rev. 1.20
Bit
7
6
5
4
3
2
1
0
Name
PBPS3
PBPS2
PBPS1
PBPS0
PAPS3
PAPS2
PAPS1
PAPS0
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
PBPS3~PBPS2: PB7~PB4 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 5~4
PBPS1~PBPS0: PB3~PB0 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 3~2
PAPS3~PAPS2: PA7 and 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 1~0
PAPS1~PAPS0: PA3~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.)
79
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
SLEDC1 Register – BS87B12A-3
Bit
7
6
5
4
3
2
1
0
Name
—
—
—
—
PCPS3
PCPS2
PCPS1
PCPS0
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
PCPS3~PCPS2: PC7~PC4 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 1~0
PCPS1~PCPS0: PC3~PC0 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.)
SLEDC1 Register – BS87C16A-3 & BS87D20A-3
Rev. 1.20
Bit
7
6
5
4
3
2
1
0
Name
PDPS3
PDPS2
PDPS1
PDPS0
PCPS3
PCPS2
PCPS1
PCPS0
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
PDPS3~PDPS2: PD7~PD4 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 5~4
PDPS1~PDPS0: PD3~PD0 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 3~2
PCPS3~PCPS2: PC7~PC4 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 1~0
PCPS1~PCPS0: PC3~PC0 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.)
80
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
SLEDC2 Register – BS87D20A-3
Bit
7
6
5
4
3
2
1
0
Name
—
—
PFPS1
PFPS0
PEPS3
PEPS2
PEPS1
PEPS0
R/W
—
—
R/W
R/W
R/W
R/W
R/W
R/W
POR
—
—
0
0
0
0
0
0
Bit 7~6
Unimplemented, read as 0.
Bit 5~4
PFPS1~PFPS0: PF3~PF0 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 3~2
PEPS3~PEPS2: PE7~PE4 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 1~0
PEPS1~PEPS0: PE3~PE0 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.)
Pin-remapping Function – BS87B12A-3 only
The flexibility of the microcontroller range is greatly enhanced by the use of pins that have more
than one function. Limited numbers of pins can force serious design constraints on designers but
by supplying pins with multi-functions, many of these difficulties can be overcome. The way in
which the pin function of specific pins is selected is different for each function and a priority order
is established where more than one pin function is selected simultaneously. Note that the pinremapping function is only available for the BS87B12A-3 device.
Pin-remapping Selection Register
The limited number of supplied pins in a package can impose restrictions on the amount of functions
a certain device can contain. However by allowing the same pins to share several different functions
and providing a means of function selection, a wide range of different functions can be incorporated
into even relatively small package sizes.
• IFS Register
Rev. 1.20
Bit
7
6
5
4
3
Name
—
—
—
—
CTP0BPS
2
R/W
—
—
—
—
R/W
R/W
R/W
R/W
POR
—
—
—
—
0
0
0
0
Bit 7~4
Unimplemented, read as 0.
Bit 3
CTP0BPS: CTP0B pin remapping function selection
0: CTP0B on PC6
1: CTP0B on PC2
Bit 2
CTP0PS: CTP0 pin remapping function selection
0: CTP0 on PC7
1: CTP0 on PC3
Bit 1
OCVPAI2P: OCVPAI2 pin remapping function selection
0: OCVPAI2 on PC7
1: OCVPAI2 on PC3
81
1
0
CTP0PS OCVPAI2PS OCVPAI1PS
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
Bit 0
OCVPAI1P: OCVPAI1 pin remapping function selection
0: OCVPAI1 on PC6
1: OCVPAI1 on PC2
I/O Pin Structures
The accompanying diagram illustrates the internal structures of the I/O logic function. As the exact
logical construction of the I/O pin will differ from this drawing, 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
Cont�ol Bit
Data Bus
W�ite Cont�ol Registe�
Chip Reset
Read Cont�ol Registe�
D
Weak
Pull-up
CK Q
S
I/O pin
Data Bit
D
W�ite Data Registe�
Q
Pull-high
Registe�
Sele�t
Q
CK Q
S
Read Data Registe�
Syste� Wake-up
M
U
X
wake-up Sele�t
PA only
Logic Function Input/Output Structure
Programming Considerations
Within the user program, one of the things first to consider is port initialisation. After a reset, all
of the I/O data and port control registers will be set to high. This means that all I/O pins will be
defaulted 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 are then programmed to setup
some pins as outputs, these output pins will have an initial high output value unless the associated
port data registers are first programmed. Selecting which pins are inputs and which are outputs can
be achieved byte-wide by loading the correct values into the appropriate port control register or
by programming individual bits in the port control register using the "SET [m].i" and "CLR [m].i"
instructions. Note that when using these bit control instructions, a read-modify-write operation takes
place. The microcontroller must first read in the data on the entire port, modify it to the required new
bit values and then rewrite this data back to the output ports.
Port A has the additional capability of providing wake-up functions. When the device is in the
SLEEP or IDLE Mode, various methods are available to wake the device up. One of these is a high
to low transition of any of the Port A pins. Single or multiple pins on Port A can be setup to have this
function.
Rev. 1.20
82
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
Timer Modules – TM
One of the most fundamental functions in any microcontroller devices is the ability to control and
measure time. To implement time related functions the device includes several Timer Modules,
generally 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
interrupts. The addition of input and output pins for each TM ensures that users are provided with
timing units with a wide and flexible range of features.
The common features of the different TM types are described here with more detailed information
provided in the individual Compact and Periodic TM sections.
Introduction
These devices contain several TMs and each individual TM can be categorised as a certain type,
namely Compact Type TM or Periodic Type TM. Although similar in nature, the different TM types
vary in their feature complexity. The common features to all of the Compact and Periodic TMs
will be described in this section and the detailed operation regarding each of the TM types will be
described in separate sections. The main features and differences between the two types of TMs are
summarised in the accompanying table.
TM Function
CTM
PTM
Timer/Counter
√
√
Input Capture
—
√
Compare Match Output
√
√
PWM Channels
1
1
Single Pulse Output
—
1
Edge
Edge
Duty or Period
Duty or Period
PWM Alignment
PWM Adjustment Period & Duty
TM Function Summary
Device
CTM
PTM
BS87B12A-3
CTM0
PTM0
BS87C16A-3
CTM0
PTM0, PTM1
CTM0, CTM1
PTM0, PTM1
BS87D20A-3
TM Name/Type Summary
TM Operation
The different types of TM offer a diverse range of functions, from simple timing operations to PWM
signal generation. The key to understanding how the TM operates is to see it in terms of a free
running count-up counter whose value is then compared with the value of pre-programmed internal
comparators. When the free running count-up counter has the same value as the pre-programmed
comparator, known as a compare match situation, a TM interrupt signal will be generated which
can clear the counter and perhaps also change the condition of the TM output pin. The internal TM
counter is driven by a user selectable clock source, which can be an internal clock or an external pin.
Rev. 1.20
83
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
TM Clock Source
The clock source which drives the main counter in each TM can originate from various sources.
The selection of the required clock source is implemented using the xTnCK2~xTnCK0 bits in the
xTMn control registers, where "x" stands for C or P type TM and "n" stands for the specific TM
serial number. The clock source can be a ratio of the system clock, fSYS, or the internal high clock,
fH, the fSUB clock source or the external xTCKn pin. The xTCKn pin clock source is used to allow an
external signal to drive the TM as an external clock source for event counting.
TM Interrupts
The Compact or Periodic type TM each has two internal interrupt, one for each of the internal
comparator A or comparator P, which generate a TM interrupt when a compare match condition
occurs. When a TM interrupt is generated, it can be used to clear the counter and also to change the
state of the TM output pin.
TM External Pins
Each of the TMs, irrespective of what type, has two TM input pins, with the label xTCKn and PTPnI
respectively. The xTMn input pin, xTCKn, is essentially a clock source for the xTMn and is selected
using the xTnCK2~xTnCK0 bits in the xTMnC0 register. This external TM input pin allows an
external clock source to drive the internal TM. The xTCKn input pin can be chosen to have either a
rising or falling active edge. The PTCKn pins are also used as the external trigger input pin in single
pulse output mode for the PTMn.
The other PTM input pin, PTPnI, is the capture input whose active edge can be a rising edge, a
falling edge or both rising and falling edges and the active edge transition type is selected using the
PTnIO1~PTnIO0 bits in the PTMnC1 register. There is another capture input, PTCKn, for PTMn
capture input mode, which can be used as the external trigger input source except the PTPnI pin.
The TMs each have two output pin, xTPn and xTPnB. 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 and xTPnB output pins are also the pins
where the xTMn generates the PWM output waveform. As the xTMn output pins are pin-shared
with other functions, the TM output function must first be setup using the relevant registers. A signal
bit in the register determines if its associated pin is to be used as an external TM output pin or if it is
to have another function. The number of external pins for each TM type is different, the details are
provided in the accompanying table.
Device
CTM
PTM
Input
Output
Input
Output
BS87B12A-3
CTCK0
CTP0, CTP0B
PTCK0, PTP0I
PTP0, PTP0B
BS87C16A-3
CTCK0
CTP0, CTP0B
PTCK0, PTP0I
PTCK1, PTP1I
PTP0, PTP0B
PTP1, PTP1B
BS87D20A-3
CTCK0
CTCK1
CTP0, CTP0B
CTP1, CTP1B
PTCK0, PTP0I
PTCK1, PTP1I
PTP0, PTP0B
PTP1, PTP1B
TM External Pins
Rev. 1.20
84
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
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.
TMPC0 Register – BS87B12A-3
Bit
7
6
5
4
3
2
1
0
Name
VREFS
—
—
—
PTM0PC1
PTM0PC0
CTM0PC1
CTM0PC0
R/W
R/W
—
—
—
R/W
R/W
R/W
R/W
POR
0
—
—
—
0
0
0
0
Bit 7
VREFS: VREF pin control
0: Disabled
1: Enabled
Bit 6~4
Unimplemented, read as 0.
Bit 3
PTM0PC1: PTP0B pin control
0: Disabled
1: Enabled
Bit 2
PTM0PC0: PTP0 pin control
0: Disabled
1: Enabled
Bit 1
CTM0PC1: CTP0B pin control
0: Disabled
1: Enabled
Bit 0
CTM0PC0: CTP0 pin control
0: Disabled
1: Enabled
TMPC0 Register – BS87C16A-3 & BS87D20A-3
Bit
7
6
Name
VREFS
—
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
Rev. 1.20
5
4
3
2
1
0
PTM1PC1 PTM1PC0 PTM0PC1 PTM0PC0 CTM0PC1 CTM0PC0
VREFS: VREF pin control
0: Disabled
1: Enabled
Bit 6
Unimplemented, read as 0.
Bit 5
PTM1PC1: PTP1B pin control
0: Disabled
1: Enabled
Bit 4
PTM1PC0: PTP1 pin control
0: Disabled
1: Enabled
Bit 3
PTM0PC1: PTP0B pin control
0: Disabled
1: Enabled
Bit 2
PTM0PC0: PTP0 pin control
0: Disabled
1: Enabled
85
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
Bit 1
CTM0PC1: CTP0B pin control
0: Disabled
1: Enabled
Bit 0
CTM0PC0: CTP0 pin control
0: Disabled
1: Enabled
TMPC1 Register – BS87D20A-3
Bit
7
6
5
4
3
2
1
0
Name
—
—
—
—
—
—
CTM1PC1
CTM1PC0
R/W
—
—
—
—
—
—
R/W
R/W
POR
—
—
—
—
—
—
0
0
Bit 7~2
Unimplemented, read as 0.
Bit 1
CTM1PC1: CTP1B pin control
0: Disabled
1: Enabled
Bit 0
CTM1PC0: CTP1 pin control
0: Disabled
1: Enabled
PC7 Output Fun�tion
PC7/CTP0
CCR output
CTM0
PC7
PC� Output Fun�tion
CTM0PC0
PC�/CTP0B
PC�
CTM0PC1
CTCK0 input
PA4/CTCK0
CTM0 Function Pin Control Block Diagram
PF1 Output Fun�tion
PF1/CTP1
CCR output
CTM1
PF1
PF2 Output Fun�tion
CTM1PC0
PF2/CTP1B
PF2
CTCK1 input
CTM1PC1
PF0/CTCK1
CTM1 Function Pin Control Block Diagram – BS87D20A-3
Rev. 1.20
86
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
PC� Output Fun�tion
PC�/PTP0
PTM0PC0
PC�
CCR output
PC4 Output Fun�tion
PC4/PTP0B
PTM0PC1
PC4
PTM0
PA2/PTP0I
PTM0 Captu�e input
PT0CAPTS
PTCK0 input
PA0/PTCK0
PTM0 Function Pin Control Block Diagram
PB� Output Fun�tion
PB�/PTP1
PTM1PC0
PB�
CCR output
PD3 Output Fun�tion
PD3/PTP1B
PTM1PC1
PD3
PTM1
PB7/PTP1I
PTM1 Captu�e input
PT1CAPTS
PTCK1 input
PB�/PTCK1
PTM1 Function Pin Control Block Diagram – BS87C16A-3 & BS87D20A-3
Rev. 1.20
87
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
Programming Considerations
The TM Counter Registers and the Capture/Compare CCRA and CCRP registers, all have a low
and high byte structure. The high bytes can be directly accessed, but as the low bytes can only be
accessed via an internal 8-bit buffer, reading or writing to these register pairs must be carried out in
a specific way. The important point to note is that data transfer to and from the 8-bit buffer and its
related low byte only takes place when a write or read operation to its corresponding high byte is
executed.
As the CCRA and CCRP registers are implemented in the way shown in the following diagram and
accessing these register pairs is carried out in a specific way as described above, it is recommended
to use the "MOV" instruction to access the CCRA and CCRP low byte registers, named xTMnAL
and PTMnRPL, using the following access procedures. Accessing the CCRA or CCRP low byte
registers without following these access procedures will result in unpredictable values.
xTMn Counte� Registe� (Read only)
xTMnDL
xTMnDH
8-�it Buffe�
xTMnAL
xTMnAH
xTMn CCRA Registe� (Read/W�ite)
PTMnRPL PTMnRPH
PTMn CCRP Registe� (Read/W�ite)
Data Bus
The following steps show the read and write procedures:
• Writing Data to CCRA or CCRP
♦♦
Step 1. Write data to Low Byte xTMnAL or PTMnRPL
––note that here data is only written to the 8-bit buffer.
♦♦
Step 2. Write data to High Byte xTMnAH or PTMnRPH
––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. 1.20
♦♦
Step 1. Read data from the High Byte xTMnDH, xTMnAH or PTMnRPH
––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 xTMnDL, xTMnAL or PTMnRPL
––this step reads data from the 8-bit buffer.
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December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
Compact Type TM – CTM0, CTM1
The Compact Type TM contains three operating modes, which are Compare Match Output, Timer/
Event Counter and PWM Output modes. The Compact TM can also be controlled with an external
input pin and can drive two external output pins.
Device
CTM Core
CTM Input Pin
CTM Output Pin
Note
BS87B12A-3
10-bit CTM
(CTM0)
CTCK0
CTP0, CTP0B
n=0
BS87C16A-3
10-bit CTM
(CTM0)
CTCK0
CTP0, CTP0B
n=0
BS87D20A-3
10-bit CTM
(CTM0, CTM1)
CTCK0
CTCK1
CTP0, CTP0B
CTP1, CTP1B
n=0, 1
CCRP
fSYS/4
fSYS
fH/16
fH/64
fSUB
fSUB
3-bit Comparator P
001
b7~b9
011
10-bit Count-up Counter
100
101
111
CTnON
CTnPAU
CTnCK2~CTnCK0
b0~b10
10-bit Comparator A
CTMnPF Interrupt
CTnOC
010
110
CTCKn
Comparator P Match
000
Counter Clear
0
1
CTnCCLR
Comparator A Match
Output
Control
Polarity
Control
CTnM1, CTnM0
CTnIO1, CTnIO0
CTnPOL
Output
Complementary
CTPn
CTPnB
CTMnAF Interrupt
CCRA
Compact Type TM Block Diagram – n=0 or 1
Compact Type TM Operation
The size of Compact TM is 10-bit wide and its core is a 10-bit count-up counter which is driven by
a user selectable internal or external clock source. There are also two internal comparators with the
names, Comparator A and Comparator P. These comparators will compare the value in the counter
with CCRP and CCRA registers. The CCRP comparator 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 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 CTnON 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 CTM interrupt signal will also usually be generated. The Compact
Type TM can operate in a number of different operational modes, can be driven by different clock
sources including an input pin and can also control an output pin. All operating setup conditions are
selected using relevant internal registers.
Rev. 1.20
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Touch A/D Flash MCU with OCVP
Compact Type TM Register Description
Overall operation of the Compact TM is controlled using a series of registers. A read only register
pair exists to store the internal counter 10-bit value, while a read/write register pair exists to store
the internal 10-bit CCRA value. The remaining two registers are control registers which setup the
different operating and control modes as well as the CCRP bits.
Bit
Register
Name
7
6
5
4
3
CTMnC0
CTnPAU
CTnCK2
CTnCK1
CTnCK0
CTnON
CTnRP2 CTnRP1
CTMnC1
CTnM1
CTnM0
CTnIO1
CTnIO0
CTnOC
CTnPOL CTnDPX CTnCCLR
CTMnDL
D7
D6
D5
D4
D3
D2
D1
D0
CTMnDH
—
—
—
—
—
—
D9
D8
CTMnAL
D7
D6
D5
D4
D3
D2
D1
D0
CTMnAH
—
—
—
—
—
—
D9
D8
2
1
0
CTnRP0
10-bit Compact TypeTM Registers List – n=0 or 1
CTMnDL 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
CTMn Counter Low Byte Register bit 7 ~ bit 0
CTMn 10-bit Counter bit 7 ~ bit 0
CTMnDH Register
Bit
7
6
5
4
3
2
1
0
Name
—
—
—
—
—
—
D9
D8
R/W
—
—
—
—
—
—
R
R
POR
—
—
—
—
—
—
0
0
Bit 7~2:
Unimplemented, read as 0.
Bit 1~0:
CTMn Counter High Byte Register bit 1 ~ bit 0
CTMn 10-bit Counter bit 9 ~ bit 8
CTMnAL Register
Bit
7
6
5
4
3
2
1
0
Name
D7
D6
D5
D4
D3
D2
D1
D0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
0
0
0
0
0
0
0
3
2
1
0
Bit 7~0
CTMn CCRA Low Byte Register bit 7 ~ bit 0
CTMn 10-bit CCRA bit 7 ~ bit 0
CTMnAH Register
Bit
Rev. 1.20
7
6
5
4
Name
—
—
—
—
—
—
D9
D8
R/W
—
—
—
—
—
—
R/W
R/W
POR
—
—
—
—
—
—
0
0
Bit 7~2:
Unimplemented, read as 0.
Bit 1~0:
CTMn CCRA High Byte Register bit 1 ~ bit 0
CTMn 10-bit CCRA bit 9 ~ bit 8
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December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
CTMnC0 Register
Rev. 1.20
Bit
7
6
5
4
3
2
1
0
Name
CTnPAU
CTnCK2
CTnCK1
CTnCK0
CTnON
CTnRP2
CTnRP1
CTnRP0
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
CTnPAU: CTMn 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 CTMn will remain powered
up and continue to consume power. The counter will retain its residual value when
this bit changes from low to high and resume counting from this value when the bit
changes to a low value again.
Bit 6~4
CTnCK2~CTnCK0: Select CTMn Counter clock
000: fSYS/4
001: fSYS
010: fH/16
011: fH/64
100: fSUB
101: fSUB
110: CTCKn rising edge clock
111: CTCKn falling edge clock
These three bits are used to select the clock source for the CTMn. 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 3
CTnON: CTMn Counter On/Off control
0: Off
1: On
This bit controls the overall on/off function of the CTMn. Setting the bit high enables
the counter to run while clearing the bit disables the CTMn. Clearing this bit to zero
will stop the counter from counting and turn off the CTMn 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 CTMn is in
the Compare Match Output Mode then the CTMn output pin will be reset to its initial
condition, as specified by the CTnOC bit, when the CTnON bit changes from low to
high.
Bit 2~0
CTnRP2~CTnRP0: CTMn CCRP 3-bit register, compared with the CTMn counter
bit 9~bit 7
Comparator P match period =
0: 1024 CTMn clocks
1~7: (1~7) x 128 CTMn 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 3 bits. The result of this
comparison can be selected to clear the internal counter if the CTnCCLR bit is set to
zero. Setting the CTnCCLR 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 eight bits to zero is in effect allowing the counter to overflow at its
maximum value.
91
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
CTMnC1 Register
Rev. 1.20
Bit
7
6
5
4
3
Name
CTnM1
CTnM0
CTnIO1
CTnIO0
CTnOC
2
1
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
CTnPOL CTnDPX
0
CTnCCLR
Bit 7~6
CTnM1~CTnM0: Select CTMn Operating Mode
00: Compare Match Output Mode
01: Undefined
10: PWM Output Mode
11: Timer/Counter Mode
These bits setup the required operating mode for the CTMn. To ensure reliable
operation the CTMn should be switched off before any changes are made to the
CTnM1 and CTnM0 bits. In the Timer/Counter Mode, the CTMn output pin control
will be disabled.
Bit 5~4
CTnIO1~CTnIO0: Select CTMn external pin CTPn function
Compare Match Output Mode
00: No change
01: Output low
10: Output high
11: Toggle output
PWM Output Mode
00: PWM output inactive state
01: PWM output active state
10: PWM output
11: Undefined
Timer/Counter Mode
Unused
These two bits are used to determine how the CTMn output pin changes state when a
certain condition is reached. The function that these bits select depends upon in which
mode the CTMn is running.
In the Compare Match Output Mode, the CTnIO1 and CTnIO0 bits determine how the
CTMn output pin changes state when a compare match occurs from the Comparator A.
The CTMn 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 CTMn
output pin should be setup using the CTnOC bit in the CTMnC1 register. Note that
the output level requested by the CTnIO1 and CTnIO0 bits must be different from the
initial value setup using the CTnOC bit otherwise no change will occur on the CTMn
output pin when a compare match occurs. After the CTMn output pin changes state,
it can be reset to its initial level by changing the level of the CTnON bit from low to
high.
In the PWM output mode, the CTnIO1 and CTnIO0 bits determine how the CTMn
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 CTnIO1 and CTnIO0 bits only after the CTMn has been switched off.
Unpredictable PWM outputs will occur if the CTnIO1 and CTnIO0 bits are changed
when the CTMn is running.
92
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
Rev. 1.20
Bit 3
CTnOC: CTMn CTPn Output control
Compare Match Output Mode
0: Initial low
1: Initial high
PWM Output Mode
0: Active low
1: Active high
This is the output control bit for the CTMn output pin. Its operation depends upon
whether CTMn is being used in the Compare Match Output Mode or in the PWM
Output Mode. It has no effect if the CTMn is in the Timer/Counter Mode. In the
Compare Match Output Mode it determines the logic level of the CTMn 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 2
CTnPOL: CTMn CTPn Output polarity control
0: Non-inverted
1: Inverted
This bit controls the polarity of the CTPn output pin. When the bit is set high the
CTMn output pin will be inverted and not inverted when the bit is zero. It has no effect
if the CTMn is in the Timer/Counter Mode.
Bit 1
CTnDPX: CTMn PWM duty/period control
0: CCRP – period; CCRA – duty
1: CCRP – duty; CCRA – period
This bit determines which of the CCRA and CCRP registers are used for period and
duty control of the PWM waveform.
Bit 0
CTnCCLR: CTMn Counter Clear condition selection
0: Comparator P match
1: Comparator A match
This bit is used to select the method which clears the counter. Remember that the
CTMn contains two comparators, Comparator A and Comparator P, either of which
can be selected to clear the internal counter. With the CTnCCLR 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 CTnCCLR bit is not
used in the PWM Output Mode.
93
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
Compact Type TM Operation Modes
The Compact Type TM can operate in one of three operating modes, Compare Match Output Mode,
PWM Output Mode or Timer/Counter Mode. The operating mode is selected using the CTnM1 and
CTnM0 bits in the CTMnC1 register.
Compare Match Output Mode
To select this mode, bits CTnM1 and CTnM0 in the CTMnC1 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 CTnCCLR 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 CTMnAF and CTMnPF interrupt request flags
for Comparator A and Comparator P respectively, will both be generated.
If the CTnCCLR bit in the CTMnC1 register is high then the counter will be cleared when a compare
match occurs from Comparator A. However, here only the CTMnAF interrupt request flag will be
generated even if the value of the CCRP bits is less than that of the CCRA registers. Therefore when
CTnCCLR is high no CTMnPF interrupt request flag will be generated. If the CCRA bits are all
zero, the counter will overflow when it reaches its maximum value. However, here the CTMnAF
interrupt request flag will not be generated.
As the name of the mode suggests, after a comparison is made, the CTMn output pin, will change
state. The CTMn output pin condition however only changes state when a CTMnAF interrupt
request flag is generated after a compare match occurs from Comparator A. The CTMnPF interrupt
request flag, generated from a compare match occurs from Comparator P, will have no effect on
the CTMn output pin. The way in which the CTMn output pin changes state are determined by
the condition of the CTnIO1 and CTnIO0 bits in the CTMnC1 register. The CTMn output pin can
be selected using the CTnIO1 and CTnIO0 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 CTMn
output pin, which is setup after the CTnON bit changes from low to high, is setup using the CTnOC
bit. Note that if the CTnIO1 and CTnIO0 bits are zero then no pin change will take place.
Rev. 1.20
94
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
Counte� ove�flow
Counte� Value
0x3FF
CTnCCLR = 0; CTnM [1:0] = 00
CCRP > 0
Counte� �lea�ed �y CCRP value
CCRP=0
CCRP > 0
Counte�
Resta�t
Resu�e
CCRP
Pause
CCRA
Stop
Ti�e
CTnON
CTnPAU
CTnPOL
CCRP Int. flag
CTMnPF
CCRA Int. flag
CTMnAF
CTMn O/P Pin
Output pin set to
initial Level Low if
CTnOC=0
Output not affe�ted �y
CTMnAF flag. Re�ains High
until �eset �y CTnON �it
Output Toggle
with CTMnAF flag
He�e CTnIO [1:0] = 11
Toggle Output sele�t
Note CTnIO [1:0] = 10
A�tive High Output sele�t
Output Inve�ts
when CTnPOL is high
Output Pin
Reset to Initial value
Output �ont�olled �y othe�
pin-sha�ed fun�tion
Compare Match Output Mode – CTnCCLR=0
Note: 1. With CTnCCLR=0 a Comparator P match will clear the counter
2. The CTMn output pin is controlled only by the CTMnAF flag
3. The output pin is reset to its initial state by a CTnON bit rising edge
4. n=0 or 0~1 is dependent upon which device is selected
Rev. 1.20
95
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
Counte� Value
CTnCCLR = 1; CTnM [1:0] = 00
CCRA = 0
Counte� ove�flow
CCRA > 0 Counte� �lea�ed �y CCRA value
0x3FF
CCRA=0
Resu�e
CCRA
Pause
Stop
Counte� Resta�t
CCRP
Ti�e
CTnON
CTnPAU
CTnPOL
No CTMnAF flag
gene�ated on
CCRA ove�flow
CCRA Int. flag
CTMnAF
CCRP Int. flag
CTMnPF
CTMn O/P Pin
CTMnPF not
gene�ated
Output pin set to
initial Level Low if
CTnOC=0
Output does
not �hange
Output Toggle
with CTMnAF flag
He�e CTnIO [1:0] = 11
Toggle Output sele�t
Output not affe�ted �y
CTMnAF flag. Re�ains High
until �eset �y CTnON �it
Note CTnIO [1:0] = 10
A�tive High Output sele�t
Output Inve�ts
when CTnPOL is high
Output Pin
Reset to Initial value
Output �ont�olled �y othe�
pin-sha�ed fun�tion
Compare Match Output Mode – CTnCCLR=1
Note: 1. With CTnCCLR=1 a Comparator A match will clear the counter
2. The CTMn output pin is controlled only by the CTMnAF flag
3. The output pin is reset to its initial state by a CTnON bit rising edge
4. A CTMnPF flag is not generated when CTnCCLR=1
5. n=0 or 0~1 is dependent upon which device is selected
Rev. 1.20
96
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
Timer/Counter Mode
To select this mode, bits CTnM1 and CTnM0 in the CTMnC1 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
CTMn 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 CTMn 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 CTnM1 and CTnM0 in the CTMnC1 register should be set to 10
respectively. The PWM function within the CTMn 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 CTMn output pin, a square wave AC waveform can be
generated with varying equivalent DC RMS values.
As both the period and duty cycle of the PWM waveform can be controlled, the choice of generated
waveform is extremely flexible. In the PWM mode, the CTnCCLR 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 CTnDPX bit in the CTMnC1 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 CTnOC bit in the CTMnC1 register is used
to select the required polarity of the PWM waveform while the two CTnIO1 and CTnIO0 bits are
used to enable the PWM output or to force the CTMn output pin to a fixed high or low level. The
CTnPOL bit is used to reverse the polarity of the PWM output waveform.
• 10-bit CTMn, PWM Mode, Edge-aligned Mode, CTnDPX=0
CCRP
1~7
Period
CCRP×128
Duty
0
1024
CCRA
If fSYS=16MHz, CTMn clock source is fSYS/4, CCRP=4 and CCRA=128,
The CTMn PWM output frequency=(fSYS/4)/(4×128)=fSYS/2048=8 kHz, duty=128/(4×128)= 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 CTMn, PWM Mode, Edge-aligned Mode, CTnDPX=1
CCRP
1~7
Period
0
CCRA
Duty
CCRP×128
1024
The PWM output period is determined by the CCRA register value together with the CTMn clock
while the PWM duty cycle is defined by the CCRP register value except when the CCRP value is
equal to 0.
Rev. 1.20
97
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
Counte� Value
CTnDPX = 0; CTnM [1:0] = 10
Counte� �lea�ed �y
CCRP
Counte� Reset when
CTnON �etu�ns high
CCRP
Pause
Resu�e
Counte� Stop if
CTnON �it low
CCRA
Ti�e
CTnON
CTnPAU
CTnPOL
CCRA Int. flag
CTMnAF
CCRP Int. flag
CTMnPF
CTMn O/P Pin
(CTnOC=1)
CTMn O/P Pin
(CTnOC=0)
PWM �esu�es
Output �ont�olled �y ope�ation
othe� pin-sha�ed fun�tion
Output Inve�ts
when CTnPOL = 1
PWM Pe�iod set �y CCRP
PWM Duty Cy�le
set �y CCRA
PWM Output Mode – CTnDPX=0
Note: 1. Here CTnDPX=0 – Counter cleared by CCRP
2. A counter clear sets the PWM Period
3. The internal PWM function continues running even when CTnIO [1:0]=00 or 01
4. The CTnCCLR bit has no influence on PWM operation
5. n=0 or 0~1 is dependent upon which device is selected
Rev. 1.20
98
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
Counte� Value
CTnDPX = 1; CTnM [1:0] = 10
Counte� �lea�ed �y
CCRA
Counte� Reset when
CTnON �etu�ns high
CCRA
Pause
Resu�e
Counte� Stop if
CTnON �it low
CCRP
Ti�e
CTnON
CTnPAU
CTnPOL
CCRP Int. flag
CTMnPF
CCRA Int. flag
CTMnAF
CTMn O/P Pin
(CTnOC=1)
CTMn O/P Pin
(CTnOC=0)
PWM Duty Cy�le
set �y CCRP
PWM �esu�es
ope�ation
Output �ont�olled �y
othe� pin-sha�ed fun�tion
Output Inve�ts
when CTnPOL = 1
PWM Pe�iod set �y CCRA
PWM Output Mode – CTnDPX=1
Note: 1. Here CTnDPX=1 – Counter cleared by CCRA
2. A counter clear sets the PWM Period
3. The internal PWM function continues even when CTnIO [1:0]=00 or 01
4. The CTnCCLR bit has no influence on PWM operation
5. n=0 or 0~1 depending upon which device is selected.
Rev. 1.20
99
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
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
also be controlled with two external input pins and can drive two external output pin.
Device
PTM Core
PTM Input Pin
PTM Output Pin
Note
BS87B12A-3
10-bit PTM
(PTM0)
PTCK0
PTP0, PTP0B
n=0
BS87C16A-3
10-bit PTM
(PTM0, PTM1)
PTCK0
PTCK1
PTP0, PTP0B
PTP1, PTP1B
n=0, 1
BS87D20A-3
10-bit PTM
(PTM0, PTM1)
PTCK0
PTCK1
PTP0, PTP0B
PTP1, PTP1B
n=0, 1
CCRP
fSYS/4
fSYS
fH/16
fH/64
fSUB
fSUB
10-bit Comparator P
001
PTMnPF Interrupt
PTnOC
b0~b9
010
011
10-bit Count-up Counter
100
101
110
PTCKn
Comparator P Match
000
PTnON
PTnPAU
b0~b9
Counter Clear
PTnCCLR
111
PTnCK2~PTnCK0
10-bit Comparator A
CCRA
Output
Control
0
1
Polarity
Control
Output
Complementary
PTPn
PTPnB
PTnM1, PTnM0 PTnPOL
PTnIO1, PTnIO0
Comparator A Match
PTMnAF Interrupt
PTnIO1, PTnIO0
PTnCAPTS
Edge
Detector
0
1
PTPnI
10-bit Periodic Type TM Block Diagram – n=0 or 1
Periodic TM Operation
The size of Periodic TM is 10-bit wide and its core is a 10-bit count-up counter which is driven by
a user selectable internal or external clock source. There are also two internal comparators with the
names, Comparator A and Comparator P. These comparators will compare the value in the counter
with CCRP and CCRA registers. The CCRP and CCRA comparators are 10-bit wide whose value is
respectively compared with all counter bits.
The only way of changing the value of the 10-bit counter using the application program is to
clear the counter by changing the PTnON 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 the output pins. All operating setup conditions
are selected using relevant internal registers.
Rev. 1.20
100
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
Periodic Type TM Register Description
Overall operation of the Periodic TM is controlled using a series of registers. A read only register
pair exists to store the internal counter 10-bit value, while two read/write register pairs exist to store
the internal 10-bit CCRA and CCRP value. The remaining two registers are control registers which
setup the different operating and control modes.
Bit
Register
Name
7
6
5
4
3
2
1
0
PTMnC0
PTnPAU PTnCK2 PTnCK1 PTnCK0
PTnON
—
—
—
PTMnC1
PTnM1
PTnM0
PTnIO1
PTnIO0
PTnOC
PTMnDL
D7
D6
D5
D4
D3
PTnPOL PTnCAPTS PTnCCLR
D2
D1
D0
PTMnDH
—
—
—
—
—
—
D9
D8
PTMnAL
D7
D6
D5
D4
D3
D2
D1
D0
PTMnAH
—
—
—
—
—
—
D9
D8
PTMnRPL PTnRP7 PTnRP6 PTnRP5 PTnRP4 PTnRP3 PTnRP2
PTnRP1
PTnRP0
PTMnRPH
PTnRP9
PTnRP8
—
—
—
—
—
—
10-bit Periodic TM Registers List – n=0 or 1
PTMnDL 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
0
0
0
0
0
0
0
0
3
2
1
0
POR
Bit 7~0
PTMn Counter Low Byte Register bit 7 ~ bit 0
PTMn 10-bit Counter bit 7 ~ bit 0
PTMnDH Register
Bit
7
6
5
4
Name
—
—
—
—
—
—
D9
D8
R/W
—
—
—
—
—
—
R
R
POR
—
—
—
—
—
—
0
0
Bit 7~2
Bit 1~0
Unimplemented, read as "0"
PTMn Counter High Byte Register bit 1 ~ bit 0
PTMn 10-bit Counter bit 9 ~ bit 8
PTMnAL 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
PTMn CCRA Low Byte Register bit 7 ~ bit 0
PTMn 10-bit CCRA bit 7 ~ bit 0
PTMnAH 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
Bit 1~0
Rev. 1.20
Unimplemented, read as "0"
PTMn CCRA High Byte Register bit 1 ~ bit 0
PTMn 10-bit CCRA bit 9 ~ bit 8
101
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Touch A/D Flash MCU with OCVP
PTMnRPL Register
Bit
7
6
5
4
3
2
1
0
Name
PTnRP7
PTnRP6
PTnRP5
PTnRP4
PTnRP3
PTnRP2
PTnRP1
PTnRP0
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
PTnRP7~PTnRP0: PTMn CCRP Low Byte Register bit 7 ~ bit 0
PTMn 10-bit CCRP bit 7 ~ bit 0
PTMnRPH Register
Bit
7
6
5
4
3
2
1
0
Name
—
—
—
—
—
—
PTnRP9
PTnRP8
R/W
—
—
—
—
—
—
R/W
R/W
POR
—
—
—
—
—
—
0
0
Bit 7~2
Unimplemented, read as "0"
Bit 1~0
PTnRP9~PTnRP8: PTMn CCRP High Byte Register bit 1 ~ bit 0
PTMn 10-bit CCRP bit 9 ~ bit 8
PTMnC0 Register
Rev. 1.20
Bit
7
6
5
4
3
2
1
0
Name
PTnPAU
PTnCK2
PTnCK1
PTnCK0
PTnON
—
—
—
R/W
R/W
R/W
R/W
R/W
R/W
—
—
—
POR
0
0
0
0
0
—
—
—
Bit 7
PTnPAU: PTMn 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 PTMn will remain powered
up and continue to consume power. The counter will retain its residual value when
this bit changes from low to high and resume counting from this value when the bit
changes to a low value again.
Bit 6~4
PTnCK2~PTnCK0: Select PTMn Counter clock
000: fSYS/4
001: fSYS
010: fH/16
011: fH/64
100: fSUB
101: fSUB
110: PTCKn rising edge clock
111: PTCKn falling edge clock
These three bits are used to select the clock source for the PTMn. 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.
102
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Touch A/D Flash MCU with OCVP
Bit 3
PTnON: PTMn Counter On/Off control
0: Off
1: On
This bit controls the overall on/off function of the PTMn. Setting the bit high enables
the counter to run while clearing the bit disables the PTMn. Clearing this bit to zero
will stop the counter from counting and turn off the PTMn 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 PTMn is in
the Compare Match Output Mode then the PTMn output pin will be reset to its initial
condition, as specified by the PTnOC bit, when the PTnON bit changes from low to
high.
Bit 2~0
Unimplemented, read as "0"
PTMnC1 Register
Rev. 1.20
Bit
7
6
5
4
3
Name
PTnM1
PTnM0
PTnIO1
PTnIO0
PTnOC
2
1
0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
0
0
0
0
0
0
0
PTnPOL PTnCAPTS PTnCCLR
Bit 7~6
PTnM1~PTnM0: Select PTMn 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 PTMn. To ensure reliable
operation the PTMn should be switched off before any changes are made to the
PTnM1 and PTnM0 bits. In the Timer/Counter Mode, the PTMn output pin control
will be disabled.
Bit 5~4
PTnIO1~PTnIO0: Select PTMn external pin PTPn or PTPnI 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 PTPnI or PTCKn
01: Input capture at falling edge of PTPnI or PTCKn
10: Input capture at rising/falling edge of PTPnI or PTCKn
11: Input capture disabled
Timer/Counter Mode
Unused
These two bits are used to determine how the PTMn output pin changes state when a
certain condition is reached. The function that these bits select depends upon in which
mode the PTMn is running.
103
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Touch A/D Flash MCU with OCVP
In the Compare Match Output Mode, the PTnIO1 and PTnIO0 bits determine how the
PTMn output pin changes state when a compare match occurs from the Comparator A.
The PTMn 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 PTMn
output pin should be setup using the PTnOC bit in the PTMnC1 register. Note that
the output level requested by the PTnIO1 and PTnIO0 bits must be different from the
initial value setup using the PTnOC bit otherwise no change will occur on the PTMn
output pin when a compare match occurs. After the PTMn output pin changes state,
it can be reset to its initial level by changing the level of the PTnON bit from low to
high.
In the PWM Mode, the PTnIO1 and PTnIO0 bits determine how the TM output pin
changes state when a certain compare match condition occurs. The PTMn output
function is modified by changing these two bits. It is necessary to only change the
values of the PTnIO1 and PTnIO0 bits only after the PTMn has been switched off.
Unpredictable PWM outputs will occur if the PTnIO1 and PTnIO0 bits are changed
when the PTMn is running.
Rev. 1.20
Bit 3
PTnOC: PTMn PTPn Output control
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 PTMn output pin. Its operation depends upon
whether PTMn 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 PTMn is in the Timer/
Counter Mode. In the Compare Match Output Mode it determines the logic level of the
PTMn output pin before a compare match occurs. In the PWM Output Mode/Single
Pulse Output Mode it determines if the PWM signal is active high or active low.
Bit 2
PTnPOL: PTMn PTPn Output polarity control
0: Non-inverted
1: Inverted
This bit controls the polarity of the PTPn output pin. When the bit is set high the
PTMn output pin will be inverted and not inverted when the bit is zero. It has no effect
if the PTMn is in the Timer/Counter Mode.
Bit 1
PTnCAPTS: PTMn Capture Trigger Source selection
0: From PTPnI pin
1: From PTCKn pin
Bit 0
PTnCCLR: PTMn Counter Clear condition selection
0: Comparator P match
1: 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 PTnCCLR 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 PTnCCLR bit is not
used in the PWM Output, Single Pulse Output or Capture Input Mode.
104
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
Periodic Type TM Operation 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 PTnM1 and PTnM0 bits in the PTMnC1 register.
Compare Match Output Mode
To select this mode, bits PTnM1 and PTnM0 in the PTMnC1 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 PTnCCLR 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 PTMnAF and PTMnPF interrupt request flags
for Comparator A and Comparator P respectively, will both be generated.
If the PTnCCLR bit in the PTMnC1 register is high then the counter will be cleared when a compare
match occurs from Comparator A. However, here only the PTMnAF interrupt request flag will
be generated even if the value of the CCRP bits is less than that of the CCRA registers. Therefore
when PTnCCLR is high no PTMnPF interrupt request flag will be generated. In the Compare Match
Output Mode, the CCRA can not be set to "0".
As the name of the mode suggests, after a comparison is made, the PTMn output pin will change
state. The PTMn output pin condition however only changes state when a PTMnAF interrupt request
flag is generated after a compare match occurs from Comparator A. The PTMnPF interrupt request
flag, generated from a compare match occurs from Comparator P, will have no effect on the PTMn
output pin. The way in which the PTMn output pin changes state are determined by the condition of
the PTnIO1 and PTnIO0 bits in the PTMnC1 register. The PTMn output pin can be selected using
the PTnIO1 and PTnIO0 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 PTMn output pin, which is
setup after the PTnON bit changes from low to high, is setup using the PTnOC bit. Note that if the
PTnIO1 and PTnIO0 bits are zero then no pin change will take place.
Rev. 1.20
105
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
Counte� ove�flow
Counte� Value
0x3FF
PTnCCLR = 0; PTnM [1:0] = 00
CCRP > 0
Counte� �lea�ed �y CCRP value
CCRP=0
CCRP > 0
Counte�
Resta�t
Resu�e
CCRP
Pause
CCRA
Stop
Ti�e
PTnON
PTnPAU
PTnPOL
CCRP Int. Flag
PTMnPF
CCRA Int. Flag
PTMnAF
PTMn O/P Pin
Output pin set to
initial Level Low if
PTnOC=0
Output not affe�ted �y
PTMnAF flag. Re�ains High
until �eset �y PTnON �it
Output Toggle
with PTMnAF flag
He�e PTnIO [1:0] = 11
Toggle Output sele�t
Note PTnIO [1:0] = 10
A�tive High Output sele�t
Output Inve�ts when
PTnPOL is high
Output Pin
Reset to Initial value
Output �ont�olled �y othe�
pin-sha�ed fun�tion
Compare Match Output Mode – PTnCCLR=0
Note: 1. With PTnCCLR=0, a Comparator P match will clear the counter
2. The PTMn output pin is controlled only by the PTMnAF flag
3. The output pin is reset to its initial state by a PTnON bit rising edge
4. The 10-bit PTM maximum counter value is 0x3FF
5. n=0 or 0~1 is dependent upon which device is selected
Rev. 1.20
106
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
Counte� Value
PTnCCLR = 1; PTnM [1:0] = 00
CCRA = 0
Counte� ove�flow
CCRA > 0 Counte� �lea�ed �y CCRA value
0x3FF
CCRA=0
Resu�e
CCRA
Pause
Stop
Counte� Resta�t
CCRP
Ti�e
PTnON
PTnPAU
PTnPOL
No PTMnAF flag
gene�ated on
CCRA ove�flow
CCRA Int.
Flag PTMnAF
CCRP Int.
Flag PTMnPF
PTMn O/P
Pin
PTMnPF not
gene�ated
Output pin set to
initial Level Low if
PTnOC=0
Output does
not �hange
Output Toggle
with PTMnAF flag
He�e PTnIO [1:0] = 11
Toggle Output sele�t
Output not affe�ted �y
PTMnAF flag. Re�ains High
until �eset �y PTnON �it
Note PTnIO [1:0] = 10
A�tive High Output sele�t
Output Inve�ts
when PTnPOL is high
Output Pin
Reset to Initial value
Output �ont�olled �y
othe� pin-sha�ed fun�tion
Compare Match Output Mode – PTnCCLR=1
Note: 1. With PTnCCLR=1, a Comparator A match will clear the counter
2. The PTMn output pin is controlled only by the PTMnAF flag
3. The output pin is reset to its initial state by a PTnON bit rising edge
4. A PTMnPF flag is not generated when PTnCCLR =1
5. The 10-bit PTM maximum counter value is 0x3FF
6. n=0 or 0~1 is dependent upon which device is selected
Rev. 1.20
107
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
Timer/Counter Mode
To select this mode, bits PTnM1 and PTnM0 in the PTMnC1 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
PTMn 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 PTMn 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 PTnM1 and PTnM0 in the PTMnC1 register should be set to 10 respectively
and also the PTnIO1 and PTnIO0 bits should be set to 10 respectively. The PWM function within
the PTMn 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
PTMn output pin, a square wave AC waveform can be generated with varying equivalent DC RMS
values.
As both the period and duty cycle of the PWM waveform can be controlled, the choice of generated
waveform is extremely flexible. In the PWM mode, the PTnCCLR bit has no effect as the PWM
period. Both of the CCRP and CCRA registers are used to generate the PWM waveform, one register
is used to clear the internal counter and thus control the PWM waveform frequency, while the other
one is used to control the duty cycle. The PWM waveform frequency and duty cycle can therefore
be controlled by the values in the CCRA and CCRP registers.
An interrupt flag, one for each of the CCRA and CCRP, will be generated when a compare match
occurs from either Comparator A or Comparator P. The PTnOC bit in the PTMnC1 register is used
to select the required polarity of the PWM waveform while the two PTnIO1 and PTnIO0 bits are
used to enable the PWM output or to force the PTMn output pin to a fixed high or low level. The
PTnPOL bit is used to reverse the polarity of the PWM output waveform.
• 10-bit PTMn, PWM Output Mode
CCRP
1~1023
Period
1~1023
Duty
0
1024
CCRA
If fSYS=16MHz, TM clock source select fSYS/4, CCRP=512 and CCRA=128,
The PTMn PWM output frequency=(fSYS/4)/512=fSYS/2048=8kHz, duty=128/512=25%,
If the Duty value defined by the CCRA register is equal to or greater than the Period value, then the
PWM output duty is 100%.
Rev. 1.20
108
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
Counte� Value
PTnM [1:0] = 10
Counte� �lea�ed �y
CCRP
Counte� Reset when
PTnON �etu�ns high
CCRP
Pause
Resu�e
Counte� Stop if
PTnON �it low
CCRA
Ti�e
PTnON
PTnPAU
PTnPOL
CCRA Int. Flag
PTMnAF
CCRP Int. Flag
PTMnPF
PTMn O/P Pin
(PTnOC=1)
PTMn O/P Pin
(PTnOC=0)
PWM Duty Cy�le
set �y CCRA
PWM �esu�es
ope�ation
Output �ont�olled �y
othe� pin-sha�ed fun�tion
PWM Pe�iod set �y CCRP
Output Inve�ts
When PTnPOL = 1
PWM Mode
Note: 1. The counter is cleared by CCRP
2. A counter clear sets the PWM Period
3. The internal PWM function continues running even when PTnIO [1:0]=00 or 01
4. The PTnCCLR bit has no influence on PWM operation
5. n=0 or 0~1 is dependent upon which device is selected
Rev. 1.20
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Single Pulse Output Mode
To select this mode, bits PTnM1 and PTnM0 in the PTMnC1 register should be set to 10
respectively and also the PTnIO1 and PTnIO0 bits should be set to 11 respectively. The Single Pulse
Output Mode, as the name suggests, will generate a single shot pulse on the PTMn output pin.
The trigger for the pulse output leading edge is a low to high transition of the PTnON bit, which
can be implemented using the application program. However in the Single Pulse Mode, the PTnON
bit can also be made to automatically change from low to high using the external PTCKn pin,
which will in turn initiate the Single Pulse output. When the PTnON bit transitions to a high level,
the counter will start running and the pulse leading edge will be generated. The PTnON bit should
remain high when the pulse is in its active state. The generated pulse trailing edge will be generated
when the PTnON 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 PTnON 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 PTMn interrupt. The counter
can only be reset back to zero when the PTnON bit changes from low to high when the counter
restarts. In the Single Pulse Mode CCRP is not used. The PTnCCLR is not used in this Mode.
S/W Command
SET“PTnON”
or
PTCKn Pin
Transition
CCRA
Leading Edge
CCRA
Trailing Edge
PTnON bit
0à1
PTnON bit
1à0
S/W Command
CLR“PTnON”
or
CCRA Compare
Match
PTPn Output Pin
Pulse Width = CCRA Value
Single Pulse Generation – n=0 or 1
Rev. 1.20
110
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Touch A/D Flash MCU with OCVP
Counte� Value
PTnM [1:0] = 10 ; PTnIO [1:0] = 11
Counte� stopped �y
CCRA
Counte� Reset when
PTnON �etu�ns high
CCRA
Pause
Counte� Stops
�y softwa�e
Resu�e
CCRP
Ti�e
PTnON
Softwa�e
T�igge�
Clea�ed �y
CCRA �at�h
Auto. set �y
PTCKn pin
Softwa�e
T�igge�
Softwa�e
Clea�
Softwa�e
T�igge�
Softwa�e
T�igge�
PTCKn pin
PTCKn pin
T�igge�
PTnPAU
PTnPOL
CCRP Int. Flag
PTMnPF
No CCRP
Inte��upts
gene�ated
CCRA Int. Flag
PTMnAF
PTMn O/P Pin
(PTnOC=1)
PTMn O/P Pin
(PTnOC=0)
Output Inve�ts
when PTnPOL = 1
Pulse Width
set �y CCRA
Single Pulse Mode
Note: 1. Counter stopped by CCRA
2. CCRP is not used
3. The pulse triggered by the PTCKn pin or by setting the PTnON bit high
4. A PTCKn pin active edge will automatically set the PTnON bit high
5. In the Single Pulse Mode, PTnIO [1:0] must be set to "11" and can not be changed
6. n=0 or 0~1 is dependent upon which device is selected
Rev. 1.20
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Capture Input Mode
To select this mode bits PTnM1 and PTnM0 in the PTMnC1 register should be set to 01 respectively.
This mode enables external signals to capture and store the present value of the internal counter
and can therefore be used for applications such as pulse width measurements. The external signal is
supplied on the PTPnI or PTCKn pin, selected by the PTnCAPTS bit in the PTMnC1 register. The
input pin active edge can be either a rising edge, a falling edge or both rising and falling edges; the
active edge transition type is selected using the PTnIO1 and PTnIO0 bits in the PTMnC1 register.
The counter is started when the PTnON bit changes from low to high which is initiated using the
application program.
When the required edge transition appears on the PTPnI or PTCKn pin the present value in the
counter will be latched into the CCRA registers and a PTMn interrupt generated. Irrespective of
what events occur on the PTPnI or PTCKn pin the counter will continue to free run until the PTnON
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 PTMn 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 PTnIO1 and PTnIO0 bits can select the active trigger edge on the PTPnI or PTCKn pin
to be a rising edge, falling edge or both edge types. If the PTnIO1 and PTnIO0 bits are both set high,
then no capture operation will take place irrespective of what happens on the PTPnI or PTCKn pin,
however it must be noted that the counter will continue to run.
As the PTPnI or PTCKn pin is pin shared with other functions, care must be taken if the PTMn is in
the Input Capture Mode. This is because if the pin is setup as an output, then any transitions on this
pin may cause an input capture operation to be executed. The PTnCCLR, PTnOC and PTnPOL bits
are not used in this Mode.
Rev. 1.20
112
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Counte� Value
PTnM[1:0] = 01
Counte� �lea�ed �y
CCRP
Counte�
Stop
Counte�
Reset
CCRP
Resu�e
YY
Pause
XX
Ti�e
PTnON
PTnPAU
A�tive
edge
A�tive
edge
A�tive edge
PTMn Captu�e Pin
PTPnI o� PTCKn
CCRA Int.
Flag PTMnAF
CCRP Int.
Flag PTMnPF
CCRA Value
PTnIO [1:0] Value
XX
00 - Rising edge
YY
01 - Falling edge
XX
10 - Both edges
YY
11 - Disa�le Captu�e
Capture Input Mode
Note: 1. PTnM [1:0]=01 and active edge set by the PTnIO [1:0] bits
2. A PTMn Capture input pin active edge transfers the counter value to CCRA
3. PTnCCLR bit not used
4. No output function – PTnOC and PTnPOL bits are not used
5. CCRP determines the counter value and the counter has a maximum count value when CCRP is equal to
zero
6. n=0 or 0~1 is dependent upon which device is selected
Rev. 1.20
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Analog to Digital Converter
The need to interface to real world analog signals is a common requirement for many electronic
systems. However, to properly process these signals by a microcontroller, they must first be
converted into digital signals by A/D converters. By integrating the A/D conversion electronic
circuitry into the microcontroller, the need for external components is reduced significantly with the
corresponding follow-on benefits of lower costs and reduced component space requirements.
A/D Overview
These devices contain a multi-channel analog to digital converter which can directly interface to
external analog signals, such as that from sensors or other control signals and convert these signals
directly into a 12-bit digital value. It also can convert the internal signals, such as the internal
reference voltage, into a 12-bit digital value. The external or internal analog signal to be converted is
determined by the SAINS and SACS bit fields. When the external analog signal is to be converted,
the corresponding external channel input pin function should first be properly configured and then
the desired external channel input should be selected using the SAINS and SACS fields. Note that
when the internal analog signal is selected to be converted, all external channel analog input pin
function should first be deselected and then properly configured the SAINS and SACS fields. More
detailed information about the A/D input signal selection will be described in the "A/D converter
Control Registers" and "A/D Converter Input Signals" section respectively.
Device
External Input Channels
Internal Signal
A/D Signal Select
BS87B12A-3
BS87C16A-3
BS87D20A-3
AN0~AN7
VBG, VOCVPAO
SAINS2~SAINS0
SACS3~SACS0
The accompanying block diagram shows the internal structure of the A/D converter together with its
associated registers and control bits.
VDD
fSYS
ACE7~ACE0
AN0
AN1
SACS3~SACS0
SACKS2~
SACKS0
VREF
VREF
÷ 2N
(N=0~7)
SAVRS1~SAVRS0
ADCEN
A/D Clock
A/D Converter
Reference Voltage
A/D Converter
AN4
AN7
START
VREFS
ADBZ
VSS
SADOL
SADOH
A/D Data
Registers
ADRFS
SAINS2~
SAINS0 VBG VOCVPAO
A/D Converter Structure
Rev. 1.20
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Registers Descriptions
Overall operation of the A/D converter is controlled using five registers. A read only register pair
exists to store the A/D Converter data 12-bit value. The remaining three registers, SADC0, SADC1
and ACERL, are control registers which setup the operating conditions and control function of the
A/D converter.
Bit
Register
Name
7
6
5
4
3
2
1
0
SADOL
(ADRFS=0)
D3
D2
D1
D0
—
—
—
—
SADOL
(ADRFS=1)
D7
D6
D5
D4
D3
D2
D1
D0
S ADOH
(ADRFS=0)
D11
D10
D9
D8
D7
D6
D5
D4
SADOH
(ADRFS=1)
—
—
—
—
D11
D10
D9
D8
SACS2
SACS1
SACS0
SADC0
START
ADBZ
ADCEN
ADRFS
SACS3
SADC1
SAINS2
SAINS1
SAINS0
SAVRS1
SAVRS0
ACERL
ACE7
ACE6
ACE5
ACE4
ACE3
SACKS2 SACKS1 SACKS0
ACE2
ACE1
ACE0
A/D Converter Registers List
A/D Converter Data Registers – SADOL, SADOH
As these devices contain an internal 12-bit A/D converter, it requires two data registers to store the
converted value. These are a high byte register, known as SADOH, and a low byte register, known
as SADOL. After the conversion process takes place, these registers can be directly read by the
microcontroller to obtain the digitised conversion value. As only 12 bits of the 16-bit register space
is utilised, the format in which the data is stored is controlled by the ADRFS bit in the SADC0
register as shown in the accompanying table. D0~D11 are the A/D conversion result data bits.
Any unused bits will be read as zero. The A/D data registers contents will be unchanged if the A/D
converter is disabled.
ADRFS
0
1
SADOH
7
6
5
D11 D10 D9
0
0
0
SADOL
4
3
2
1
0
7
6
5
4
3
2
1
D8
D7
D6
D5
D4
D3
D2
D1
D0
0
0
0
0
D11 D10 D9
D8
D7
D6
D5
D4
D3
D2
D1
D0
0
0
A/D Converter Data Registers
A/D Converter Control Registers – SADC0, SADC1, ACERL
To control the function and operation of the A/D converter, three control registers known as SADC0,
SADC1 and ACERL are provided. These 8-bit registers define functions such as the selection of
which analog signal is connected to the internal A/D converter, the digitised data format, the A/D
clock source as well as controlling the start function and monitoring the A/D converter busy status.
As these devices contain only one actual analog to digital converter hardware circuit, each of the
external and internal analog signals must be routed to the converter. The SAINS field in the SADC1
register and SACS field in the SADC0 register are used to determine which analog signal derived
from the external or internal signals will be connected to the A/D converter.
The ACERL register contains the ACE7~ACE0 bits which determine which pins on I/O Ports are
used as analog inputs for the A/D converter input and which pins are not. Setting the corresponding
bit high will select the A/D input function while clearing the bit to zero will select either the I/O or
other pin-shared function. When the pin is selected to be an A/D input, its original function whether
it is an I/O or other pin-shared function will be removed. In addition, any internal pull-high resistor
connected to the pin will be automatically removed if the pin is selected to be an A/D converter input.
Rev. 1.20
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• SADC0 Register
Rev. 1.20
Bit
7
6
5
4
3
2
1
0
Name
START
ADBZ
ADCEN
ADRFS
SACS3
SACS2
SACS1
SACS0
R/W
R/W
R
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
0
0
0
0
0
0
0
Bit 7
START: Start the A/D Conversion
0→1→0: Start
This bit is used to initiate an A/D conversion process. The bit is normally low but if set
high and then cleared low again, the A/D converter will initiate a conversion process.
Bit 6
ADBZ: A/D Converter busy flag
0: No A/D conversion is in progress
1: A/D conversion is in progress
This read only flag is used to indicate whether the A/D conversion is in progress or
not. When the START bit is set from low to high and then to low again, the ADBZ flag
will be set to 1 to indicate that the A/D conversion is initiated. The ADBZ flag will be
cleared to 0 after the A/D conversion is complete.
Bit 5
ADCEN: A/D Converter function enable control
0: Disable
1: Enable
This bit controls the A/D internal function. This bit should be set to one to enable
the A/D converter. If the bit is set low, then the A/D converter will be switched off
reducing the device power consumption. When the A/D converter function is disabled,
the contents of the A/D data register pair known as SADOH and SADOL will be
unchanged.
Bit 4
ADRFS: A/D conversion data format select
0: A/D converter data format → SADOH=D [11:4]; SADOL=D [3:0]
1: A/D converter data format → SADOH=D [11:8]; SADOL=D [7:0]
This bit controls the format of the 12-bit converted A/D value in the two A/D data
registers. Details are provided in the A/D converter data register section.
Bit 3~0
SACS3~SACS0: A/D converter external analog input channel select
0000: External AN0 input
0001: External AN1 input
0010: External AN2 input
0011: External AN3 input
0100: External AN4 input
0101: External AN5 input
0110: External AN6 input
0111: External AN7 input
1xxx: Non-existed channel, input floating if selected.
These bits are used to select which external analog input channel is to be converted.
When the external analog input channel is selected, the SAINS bit field must be set
to "000", "101" or "11x". Details are summarized in the "A/D Converter Input Signal
Selection" table.
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• SADC1 Register
Bit
7
6
5
4
3
2
1
0
Name
SAINS2
SAINS1
SAINS0
SAVRS1
SAVRS0
SACKS2
SACKS1
SACKS0
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 7~5
SAINS2~SAINS0: A/D converter input signal select
000: External source – External analog channel intput, ANn
001: Internal source – Internal signal derived from the internal bandgap reference voltage,
VBG
010: Internal source – Reserved, connected to ground
011: Internal source – Internal signal derived from the OCVP OPA output signal, VOCVPAO
100: Internal source – Reserved, connected to ground
101~111: External source – External analog channel intput, ANn
Care must be taken if the SAINS field is set to "001" or "011" to select the internal
analog signal to be converted. When the internal analog signal is selected to be
converted, the external channel input pin must never be selected as the A/D input
signal by properly setting the SACS bit field with a value of "1xxx". Otherwise, the
external channel input will be connected together with the internal analog signal. This
will result in unpredictable situations such as an irreversible damage.
Bit 4~3
SAVRS1~SAVRS0: A/D converter reference voltage select
00: External VREF pin
01: Internal A/D converter power, VDD.
1x: External VREF pin
These bits are used to select the A/D converter reference voltage source. Care must
be taken if the SAVRS field is set to "01" to select the internal A/D converter power
voltage as the reference voltage source. When the internal reference voltage source
is selected, the external VREF cannot be configured as the reference voltage input by
properly configuring the VREFS bit in the TMPC0 register. Otherwise, the external
input voltage on the VREF pin will be connected to the internal A/D converter power.
Bit 2~0
SACKS2~SACKS0: A/D conversion clock source select
000: fSYS
001: fSYS/2
010: fSYS/4
011: fSYS/8
100: fSYS/16
101: fSYS/32
110: fSYS/64
111: fSYS/128
These bits are used to select the clock source for the A/D converter. It is recommended
that the A/D conversion clock frequency should be in the range from 500 kHz to
1MHz by properly configuring the SACKS2~SACKS0 bits.
• ACERL Register
Rev. 1.20
Bit
7
6
5
4
3
2
1
0
Name
ACE7
ACE6
ACE5
ACE4
ACE3
ACE2
ACE1
ACE0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
0
0
0
0
0
0
0
Bit 7
ACE7: AN7 input pin enable control
0: Disable – not A/D input
1: Enable – A/D input, AN7
Bit 6
ACE6: AN6 input pin enable control
0: Disable – not A/D input
1: Enable – A/D input, AN6
117
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Bit 5
ACE5: AN5 input pin enable control
0: Disable – not A/D input
1: Enable – A/D input, AN5
Bit 4
ACE4: AN4 input pin enable control
0: Disable – not A/D input
1: Enable – A/D input, AN4
Bit 3
ACE3: AN3 input pin enable control
0: Disable – not A/D input
1: Enable – A/D input, AN3
Bit 2
ACE2: AN2 input pin enable control
0: Disable – not A/D input
1: Enable – A/D input, AN2
Bit 1
ACE1: AN1 input pin enable control
0: Disable – not A/D input
1: Enable – A/D input, AN1
Bit 0
ACE0: AN0 input pin enable control
0: Disable – not A/D input
1: Enable – A/D input, AN0
A/D Converter Reference Voltage
The actual reference voltage supply to the A/D Converter can be supplied from the positive power
supply pin, VDD, or an external reference source supplied on pin VREF determined by the SAVRS
bit field in the SADC1 register. When the SAVRS field is set to "01", the A/D converter reference
voltage will come from the VDD pin. Otherwise, the A/D converter reference voltage will come
from the VREF pin if the SAVRS field is set to any other value except "01". When the VREF pin
is selected as the reference voltage supply pin, the VREFS bit in the TMPC0 register should first
be properly configured to enable the VREF pin function as it is pin-shared with other functions.
However, if the internal A/D converter power is selected as the reference voltage, the external VREF
pin must not be configured as the reference voltage input function to avoid the internal connection
between the VREF pin to the internal A/D converter power. Note that the analog input values must
not be allowed to exceed the value of the selected reference voltage, VDD or VREF.
A/D Converter Input Signals
All of the external A/D analog input pins are pin-shared with the I/O pins as well as other functions.
The corresponding pin-shared function selection bits ACEn in the ACERL register determine
whether the external input pins are setup as A/D converter analog channel inputs or whether they
have other functions. If the corresponding pin is setup to be an A/D converter analog channel input
by setting the ACEn bit high, the original pin function will be disabled. In this way, pins can be
changed under program control to change their function between A/D inputs and other functions.
All pull-high resistors, which are setup through register programming, will be automatically
disconnected if the pins are setup as A/D inputs. Note that it is not necessary to first setup the A/D
pin as an input in the port control register to enable the A/D input as when the relevant A/D input
function selection bits enable an A/D input, the status of the port control register will be overridden.
As these devices contain only one actual analog to digital converter hardware circuit, one of the
external or internal analog signals must be routed to the converter. The SAINS2~SAINS0 bits in
the SADC1 register are used to determine that the analog signal to be converted comes from the
external channel input or internal analog signal. The SACS3~SACS0 bits in the SADC0 register are
used to determine which external channel input is selected to be converted. If the SAINS2~SAINS0
bits are set to "000", "101" or "11x", the external channel input will be selected to be converted and
the SACS3~SACS0 bits can determine which external channel is selected.
Rev. 1.20
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When the SAINS field is set to the value of "001" or "011", the internal analog signal derived from
the Bandgap reference voltage or OCVP OPA output signal will be selected. If the internal analog
signal is selected to be converted, the external channel signal input must be switched off by setting
the SACS field to a value of "1xxx". Otherwise, the internal analog signal will be connected together
with the external channel input. This will result in unpredictable situations.
SAINS [2:0]
SACS [3:0]
Input Signals
0000~0111
AN0~AN7
000, 101, 11x
Description
External channel analog input ANn.
1xxx
—
Floating, no external channel is selected.
001
1xxx
VBG
Internal Bandgap reference voltage
010, 100
1xxx
GND
011
1xxx
VOCVPAO
Connected to the ground.
Internal OCVP OPA output signal
A/D Converter Input Signal Selection
A/D Converter Operation
The START bit in the SADC0 register is used to start the AD conversion. When the microcontroller
sets this bit from low to high and then low again, an analog to digital conversion cycle will be
initiated.
The ADBZ bit in the SADC0 register is used to indicate whether the analog to digital conversion
process is in progress or not. This bit will be automatically set to 1 by the microcontroller after
an A/D conversion is successfully initiated. When the A/D conversion is complete, the ADBZ bit
will be cleared to 0. In addition, the corresponding A/D interrupt request flag will be set in the
interrupt control register, and if the A/D interrupt is enabled, an internal A/D interrupt signal will
be generated. This A/D internal interrupt signal will direct the program flow to the associated A/D
internal interrupt address for processing. If the A/D internal interrupt is disabled, the microcontroller
can poll the ADBZ bit in the SADC0 register to check whether it has been cleared as an alternative
method of detecting the end of an A/D conversion cycle.
The clock source for the A/D converter, which originates from the system clock fSYS, can be chosen
to be either fSYS or a subdivided version of fSYS. The division ratio value is determined by the
SACKS bit field in the SADC1 register. Although the A/D clock source is determined by the system
clock fSYS and by bits SACKS2~SACKS0, there are some limitations on the maximum A/D clock
source speed that can be selected. As the recommended range of permissible A/D clock period,
tADCK, is from 0.5μs to 10μ, care must be taken for system clock frequencies. For example, if the
system clock operates at a frequency of 8MHz, the SACKS2~SACKS0 bits should not be set to 000,
001 or 111. Doing so will give A/D clock periods that are less than the minimum A/D clock period
which may result in inaccurate A/D conversion values. Refer to the following table for examples,
where values marked with an asterisk * show where, depending upon the device, special care must
be taken, as the values may be less than the specified minimum A/D Clock Period.
A/D Clock Period (tADCK)
fSYS
SACKS
SACKS
SACKS
SACKS
SACKS
SACKS
SACKS
SACKS
[2:0]=000 [2:0]=001 [2:0]=010 [2:0]=011 [2:0]=100 [2:0]=101 [2:0]=110 [2:0]=111
(fSYS/2)
(fSYS/4)
(fSYS/8)
(fSYS/16) (fSYS/32) (fSYS/64) (fSYS/128)
(fSYS)
1 MHz
1μs
2μs
4μs
8μs
16μs *
32μs *
64μs *
2 MHz
500ns
1μs
2μs
4μs
8μs
16μs *
32μs *
64μs *
4 MHz
250ns *
500ns
1μs
2μs
4μs
8μs
16μs *
32μs *
128μs *
8 MHz
125ns *
250ns *
500ns
1μs
2μs
4μs
8μs
16μs *
12 MHz
83ns *
167ns *
333ns *
667ns
1.33μs
2.67μs
5.33μs
10.67μs *
16 MHz
62.5ns *
125ns *
250ns *
500ns
1μs
2μs
4μs
8μs
A/D Clock Period Examples
Rev. 1.20
119
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
Controlling the power on/off function of the A/D converter circuitry is implemented using the
ADCEN bit in the SADC0 register. This bit must be set high to power on the A/D converter. When
the ADCEN bit is set high to power on the A/D converter internal circuitry, a certain delay, as
indicated in the timing diagram, must be allowed before an A/D conversion is initiated. Even if
no pins are selected for use as A/D inputs, if the ADCEN bit is high, then some power will still be
consumed. In power conscious applications it is therefore recommended that the ADCEN is set low
to reduce power consumption when the A/D converter function is not being used.
Conversion Rate and Timing Diagram
A complete A/D conversion contains two parts, data sampling and data conversion. The data
sampling which is defined as tADS takes 4 A/D clock cycles and the data conversion takes 12 A/D
clock cycles. Therefore a total of 16 A/D clock cycles for an analog signal A/D conversion which is
defined as tADC are necessary.
Maximum single A/D conversion rate=A/D clock period/16
The accompanying diagram shows graphically the various stages involved in an external channel
input signal analog to digital conversion process and its associated timing. After an A/D conversion
process has been initiated by the application program, the microcontroller internal hardware will
begin to carry out the conversion, during which time the program can continue with other functions.
The time taken for the A/D conversion is 16 tADCK clock cycles where tADCK is equal to the A/D clock
period.
tON2ST
ADCEN
off
on
off
A/D sampling time
tADS
A/D sampling time
tADS
Start of A/D conversion
Start of A/D conversion
on
START
ADBZ
SACS[3:0]
(SAINS=000)
End of A/D
conversion
0011B
A/D channel
switch
End of A/D
conversion
0010B
tADC
A/D conversion time
Start of A/D conversion
0000B
tADC
A/D conversion time
0001B
tADC
A/D conversion time
A/D Conversion Timing – External Channel Input
Rev. 1.20
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Touch A/D Flash MCU with OCVP
Summary of A/D Conversion Steps
The following summarises the individual steps that should be executed in order to implement an A/D
conversion process.
• Step 1
Select the required A/D conversion clock by properly programming the SACKS2~SACKS0 bits
in the SADC1 register.
• Step 2
Enable the A/D converter by setting the ADCEN bit in the SADC0 register to one.
• Step 3
Select which signal is to be connected to the internal A/D converter by correctly configuring the
SACS and SAINS bit fields
Selecting the external channel input to be converted, go to Step 4.
Selecting the internal analog signal to be converted, go to Step 5.
• Step 4
If the SAINS field is 000, 101 or 11x, the external channel input can be selected. The desired
external channel input is selected by configuring the SACS field. When the A/D input signal
comes from the external channel input, the corresponding pin should be configured as an A/D
input function by selecting the relevant pin-shared function control bits, ACEn. Then go to Step 6.
• Step 5
If the SAINS field is set to 001 or 011, the relevant internal analog signal can be selected. Before
the A/D input signal is selected to come from the internal analog signal by properly configuring
the SAINS field, the SACS field must be set to "1xxx" to select a non-existed channel input. Then
go to Step 6.
• Step 6
Select the A/D converter output data format by configuring the ADRFS bit.
• Step 7
Select the A/D converter reference voltage source by configuring the SAVRS bit field.
Select the PGA input signal and the desired PGA gain if the PGA output voltage, VR, is selected
as the A/D converter reference voltage.
• Step 8
If A/D conversion interrupt is used, the interrupt control registers must be correctly configured
to ensure the A/D interrupt function is active. The master interrupt control bit, EMI, and the A/D
conversion interrupt control bit, ADE, must both be set high in advance.
• Step 9
The A/D conversion procedure can now be initialized by setting the START bit from low to high
and then low again.
• Step 10
If A/D conversion is in progress, the ADBZ flag will be set high. After the A/D conversion
process is complete, the ADBZ flag will go low and then the output data can be read from
SADOH and SADOL registers.
Note: When checking for the end of the conversion process, if the method of polling the ADBZ bit
in the SADC0 register is used, the interrupt enable step above can be omitted.
Rev. 1.20
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Touch A/D Flash MCU with OCVP
Programming Considerations
During microcontroller operations where the A/D converter is not being used, the A/D internal
circuitry can be switched off to reduce power consumption, by setting bit ADCEN low in the
SADC0 register. When this happens, the internal A/D converter circuits will not consume power
irrespective of what analog voltage is applied to their input lines. If the A/D converter input lines are
used as normal I/Os, then care must be taken as if the input voltage is not at a valid logic level, then
this may lead to some increase in power consumption.
A/D Transfer Function
As the devices contain a 12-bit A/D converter, its full-scale converted digitised value is equal to
FFFH. Since the full-scale analog input value is equal to the actual A/D converter reference voltage,
VREF, this gives a single bit analog input value of reference voltage value divided by 4096.
1 LSB=VREF ÷ 4096
The A/D Converter input voltage value can be calculated using the following equation:
A/D input voltage=A/D output digital value × VREF ÷ 4096
The diagram shows the ideal transfer function between the analog input value and the digitised
output value for the A/D converter. Except for the digitised zero value, the subsequent digitised
values will change at a point 0.5 LSB below where they would change without the offset, and the
last full scale digitised value will change at a point 1.5 LSB below the VREF level.
Note that here the VREF voltage is the actual A/D converter reference voltage source determined by
the SAVRS field.
1.� LSB
FFFH
FFEH
FFDH
A/D Conversion
Result
03H
0.� LSB
02H
01H
0
1
2
3
4093 4094 409� 409�
VREF
409�
Analog Input Voltage
Ideal A/D Transfer Function
Rev. 1.20
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Touch A/D Flash MCU with OCVP
A/D Programming Examples
The following two programming examples illustrate how to setup and implement an A/D conversion.
In the first example, the method of polling the ADBZ bit in the SADC0 register is used to detect
when the conversion cycle is complete, whereas in the second example, the A/D interrupt is used to
determine when the conversion is complete.
Example: using an ADBZ polling method to detect the end of conversion
clr ADE; disable ADC interrupt
mov a,03H; select fSYS/8 as A/D clock and A/D input
mov SADC1,a ; signal comes from external channel
mov a,00H ; select VREF pin voltage as A/D reference voltage source
mov SADC0,a ; and AN0 is selected as the external channel input
set ADCEN ; enable the A/D converter
mov a,01H ; setup ACERL to configure pin AN0 as analog input
mov ACERL,a
:
start_conversion:
clr START ; high pulse on start bit to initiate conversion
set START ; reset A/D
clr START ; start A/D
:
polling_EOC:
sz ADBZ ; poll the SADC0 register ADBZ bit to detect end of A/D conversion
jmp polling_EOC ; continue polling
mov a,SADOL ; read low byte conversion result value
mov SADOL_buffer,a ; save result to user defined register
mov a,SADOH ; read high byte conversion result value
mov SADOH_buffer,a ; save result to user defined register
:
jmp start_conversion ; start next A/D conversion
Rev. 1.20
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Touch A/D Flash MCU with OCVP
Example: using the interrupt method to detect the end of conversion
clr ADE; disable ADC interrupt
mov a,03H; select fSYS/8 as A/D clock and A/D input
mov SADC1,a ; signal comes from external channel
mov a,00H ; select VREF pin voltage as A/D reference voltage source
mov SADC0,a ; and AN0 is selected as the external channel input
set ADCEN ; enable the A/D converter
mov a,01H ; setup ACERL to configure pin AN0 as analog input
mov ACERL,a
:
Start_conversion:
clr START ; high pulse on START bit to initiate conversion
set START ; reset A/D
clr START ; start A/D
clr ADF ; clear ADC interrupt request flag
set ADE; enable ADC interrupt
set EMI ; enable global interrupt
:
:
ADC_ISR: ; ADC interrupt service routine
mov acc_stack,a ; save ACC to user defined memory
mov a,STATUS
mov status_stack,a ; save STATUS to user defined memory
:
mov a,SADOL ; read low byte conversion result value
mov SADOL_buffer,a ; save result to user defined register
mov a,SADOH ; read high byte conversion result value
mov SADOH_buffer,a ; save result to user defined register
:
EXIT_INT_ISR:
mov a,status_stack
mov STATUS,a ; restore STATUS from user defined memory
mov a,acc_stack ; restore ACC from user defined memory
reti
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Touch A/D Flash MCU with OCVP
Touch Key Function
Each device provides multiple touch key functions. The touch key function is fully integrated and
requires no external components, allowing touch key functions to be implemented by the simple
manipulation of internal registers.
Touch Key Structure
The touch keys are pin-shared with the I/O pins, with the desired function chosen via the
corresponding selection register bits. Keys are organised into several groups, with each group known
as a module and having a module number, M0 to Mn. Each module is a fully independent set of
four Touch Keys and each Touch Key has its own oscillator. Each module contains its own control
logic circuits and register set. Examination of the register names will reveal the module number it is
referring to.
Device
BS87B12A-3
BS87C16A-3
BS87D20A-3
Total Key Number
Touch Key Module
Mn
(n=0~2)
12
Mn
(n=0~3)
16
Mn
(n=0~4)
20
M0
Touch Key
KEY1~KEY4
M1
KEY5~KEY8
M2
KEY9~KEY12
M0
KEY1~KEY4
M1
KEY5~KEY8
M2
KEY9~KEY12
M3
KEY13~KEY16
M0
KEY1~KEY4
M1
KEY5~KEY8
M2
KEY9~KEY12
M3
KEY13~KEY16
M4
KEY17~KEY20
Touch Key Structure
Rev. 1.20
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Touch A/D Flash MCU with OCVP
Touch Key Module n
KEY1
Key
OSC
KEY2
Key
OSC
TKMn16DH / TKMn16DL
Mux .
Filter
Multifrequency
16-bit C/F Counter
TKCFOV
Key
OSC
KEY3
MnDFEN
Key
OSC
KEY4
MnK4IO~MnK1IO
MnKOEN
MnMXS1~MnMXS0
MnTSS
fSYS/4
MnROEN
Reference Oscillator
TKTMR
M
U
X
8-bit Time Slot Counter
TKRCOV
5-bit unit period counter
TKMnROH / TKMnROL
TKTMR
8-bit Time Slot Counter
Preload Register
fSYS
fSYS/2
fSYS/4
fSYS/8
Overflow
M
U
X
TK16OV
16-bit Counter
TK16DL / TK16DH
TK16S1~TK16S0
Note: The structure contained in the dash line is identical for each touch key module which contains four touch
keys.
Touch Key Function Block Diagram
Touch Key Register Definition
Each touch key module, which contains four touch key functions, has its own suite registers. The
following table shows the register set for each touch key module. The Mn within the register name
refers to the Touch Key module number. The series of devices has up to five Touch Key Modules
dependent upon the selected device.
Name
Description
TKTMR
Touch key time slot 8-bit counter preload register
TKC0
Touch key function Control register 0
TK16DL
Touch key function 16-bit counter low byte
TK16DH
Touch key function 16-bit counter high byte
TKC1
Touch key function Control register 1
TKMn16DL
Touch key module n 16-bit C/F counter low byte
TKMn16DH
Touch key module n 16-bit C/F counter high byte
TKMnROL
Touch key module n reference oscillator capacitor select low byte
TKMnROH
Touch key module n reference oscillator capacitor select high byte
TKMnC0
Touch key module n Control register 0
TKMnC1
Touch key module n Control register 1
Touch Key Module Registers List
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Touch A/D Flash MCU with OCVP
Bit
Register
Name
7
6
5
4
3
2
1
0
TKTMR
D7
D6
D5
D4
D3
D2
D1
D0
TKC0
—
TKRCOV
TKST
TSCS
TK16S1
TK16S0
TK16DL
D7
D6
D5
TKCFOV TK16OV
D4
D3
D2
D1
D0
TK16DH
D15
D14
D13
D12
D11
D10
D9
D8
TKC1
—
—
—
—
—
—
TKFS1
TKFS0
D0
TKMn16DL
D7
D6
D5
D4
D3
D2
D1
TKMn16DH
D15
D14
D13
D12
D11
D10
D9
D8
TKMnROL
D7
D6
D5
D4
D3
D2
D1
D0
—
—
—
—
—
D9
D8
TKMnROH
TKMnC0
MnMXS1 MnMXS0 MnDFEN
TKMnC1
MnTSS
—
—
D4
MnSOFC MnSOF2 MnSOF1 MnSOF0
MnROEN MnKOEN MnK4IO
MnK3IO
MnK2IO
MnK1IO
Touch Key Function Registers List
TKTMR 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
D7~D0: Touch key time slot 8-bit counter preload register
The touch key time slot counter preload register is used to determine the touch key
time slot overflow time. The time slot unit period is obtained by a 5-bit counter and
equal to 32 time slot clock cycles. Therefore, the time slot counter overflow time is
equal to the following equation shown.
Time slot counter overflow time=(256-TKTMR[7:0])×32tTSC, where tTSC is the time
slot counter clock period.
TKC0 Register
Rev. 1.20
Bit
7
6
5
4
3
2
1
0
Name
—
TKRCOV
TKST
TKCFOV
TK16OV
TSCS
TK16S1
TK16S0
R/W
—
R/W
R/W
R/W
R/W
R/W
R/W
R
POR
—
0
0
0
0
0
0
0
Bit 7
Bit 6
Unimplemented, read as "0"
TKRCOV: Touch key time slot counter overflow flag
0: No overflow occurs
1: Overflow occurs
If the module 0 or all module time slot counter, selected by the TSCS bit, overflows,
the Touch Key Interrupt request flag, TKMF, will be set and all module key OSCs and
reference OSCs will automatically stop. The touch key module 16-bit C/F counter,
touch key function 16-bit counter, 5-bit time slot unit period counter and 8-bit time
slot counter will be automatically switched off.
Bit 5
TKST: Touch key detection Start control
0: Stopped or no operation
0→1: Start detection
In all modules the touch key module 16-bit C/F counter, touch key function 16-bit
counter and 5-bit time slot unit period counter will automatically be cleared when this
bit is cleared to zero. However, the 8-bit programmable time slot counter will not be
cleared. When this bit is changed from low to high, the touch key module 16-bit C/F
counter, touch key function 16-bit counter, 5-bit time slot unit period counter and 8-bit
time slot counter will be switched on together with the key and reference oscillators to
drive the corresponding counters.
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Touch A/D Flash MCU with OCVP
Bit 4
TKCFOV: Touch key module 16-bit C/F counter overflow flag
0: No overflow occurs
1: Overflow occurs
This bit is set high by the touch key module 16-bit C/F counter overflow and must be
cleared to 0 by application programs.
Bit 3
TK16OV: Touch key function 16-bit counter overflow flag
0: No overflow occurs
1: Overflow occurs
This bit is set high by the touch key function 16-bit counter overflow and must be
cleared to 0 by application programs.
Bit 2
TSCS: Touch key time slot counter select
0: Each touch key module uses its own time slot counter
1: All touch key modules use Module 0 time slot counter
Bit 1~0
TK16S1~TK16S0: Touch key function 16-bit counter clock source select
00: fSYS
01: fSYS/2
10: fSYS/4
11: fSYS/8
TKC1 Register
Bit
7
6
5
4
3
2
1
0
Name
—
—
—
—
—
—
TKFS1
TKFS0
R/W
—
—
—
—
—
—
R/W
R/W
POR
—
—
—
—
—
—
1
1
Bit 7~2
Unimplemented, read as "0"
Bit 1~0
TKFS1~TKFS0: Touch Key oscillator and Reference oscillator frequency select
00: 500 kHz
01: 1000 kHz
10: 1500 kHz
11: 2000 kHz
TK16DH/TK16DL – Touch Key Function 16-bit Counter Register Pair
Register
Bit
Name
TK16DH
7
6
5
4
3
TK16DL
2
1
D15 D14 D13 D12 D11 D10 D9
0
7
6
5
4
3
2
1
0
D8
D7
D6
D5
D4
D3
D2
D1
D0
R/W
R
R
R
R
R
R
R
R
R
R
R
R
R
R
R
R
POR
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
This register pair is used to store the touch key function 16-bit counter value. This 16-bit counter
can be used to calibrate the reference or key oscillator frequency. When the touch key time slot
counter overflows, this 16-bit counter will be stopped and the counter content will be unchanged.
This register pair will be cleared to zero when the TKST bit is set low.
Rev. 1.20
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Touch A/D Flash MCU with OCVP
TKMn16DH/TKMn16DL – Touch Key Module n 16-bit C/F Counter Register Pair
Register
TKMn16DH
Bit
Name
7
6
5
4
TKMn16DL
3
2
1
D15 D14 D13 D12 D11 D10 D9
0
7
6
5
4
3
2
1
0
D8
D7
D6
D5
D4
D3
D2
D1
D0
R/W
R
R
R
R
R
R
R
R
R
R
R
R
R
R
R
R
POR
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
This register pair is used to store the touch key module n 16-bit C/F counter value. This 16-bit C/F
counter will be stopped and the counter content will be kept unchanged when the touch key time slot
counter overflows. This register pair will be cleared to zero when the TKST bit is set low.
TKMnROH/TKMnROL – Touch Key Module n Reference Oscillator Capacitor Select Register Pair
Register
Bit
TKMnROH
7
6
5
4
3
TKMnROL
2
Name
—
—
—
—
—
—
R/W
—
—
—
—
—
—
POR
—
—
—
—
—
—
1
0
7
6
5
4
3
2
1
0
D9
D8
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 R/W
0
0
0
0
0
0
0
0
0
0
This register pair is used to store the touch key module n reference oscillator capacitor value. This
register pair will be loaded with the corresponding next time slot capacitor value from the dedicated
touch key data memory at the end of the current time slot when the auto scan mode is selected.
The reference oscillator internal capacitor value = (TKMnRO[9:0]×50pF)/1024.
TKMnC0 Register
Bit
Name
7
6
5
4
MnSOFC MnSOF2
1
0
MnSOF1
MnSOF0
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
MnMXS1~MnMXS0: Multiplexer Key Select
Bit
Rev. 1.20
D4
2
R/W
Bit 7~6
MnMXS1 MnMXS0 MnDFEN
3
Touch Key Module Number
MnMXS[1:0]
M0
M1
M2
M3
M4
00
KEY1
KEY5
KEY9
KEY13
KEY17
01
KEY2
KEY6
KEY10
KEY14
KEY18
10
KEY3
KEY7
KEY11
KEY15
KEY19
KEY20
11
KEY4
KEY8
KEY12
KEY16
BS87B12A-3
√
√
√
—
—
BS87C16A-3
√
√
√
√
—
BS87D20A-3
√
√
√
√
√
Bit 5
MnDFEN: Touch key module n multi-frequency control
0: Disable
1: Enable
This bit is used to control the touch key oscillator frequency doubling function. When
this bit is set to 1, the key oscillator frequency will be doubled.
Bit 4
D4: Data bit for test only
The bit is used for test purpose only and must be kept as "0" for normal operations.
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Touch A/D Flash MCU with OCVP
Bit 3
MnSOFC: Touch key module n C-to-F oscillator frequency hopping function control
select
0: Controlled by the MnSOF2~MnSOF0
1: Controlled by hardware circuit
This bit is used to select the touch key oscillator frequency hopping function control
method. When this bit is set to 1, the key oscillator frequency hopping function is
controlled by the hardware circuit regardless of the MnSOF2~MnSOF0 bits value.
Bit 2~0
MnSOF2~MnSOF0: Touch key module n Reference and Key oscillators hopping
frequency select
000: fHOP0 – Min. hopping frequency
001: fHOP1
010: fHOP2
011: fHOP3
100: fHOP4 – Selected touch key oscillator frequency
101: fHOP5
110: fHOP6
111: fHOP7 – Max. hopping frequency
These bits are used to select the touch key oscillator frequency for the hopping
function. Note that these bits are only available when the MnSOFC bit is cleared to 0.
TKMnC1 Register
Bit
7
6
Name
MnTSS
—
5
4
R/W
R/W
—
R/W
POR
0
—
0
3
2
1
0
MnK4IO
MnK3IO
MnK2IO
MnK1IO
R/W
R/W
R/W
R/W
R/W
0
0
0
0
0
MnROEN MnKOEN
Bit 7
MnTSS: Touch key module n time slot counter clock source select
0: Touch key module n reference oscillator
1: fSYS/4
Bit 6
Unimplemented, read as "0"
Bit 5
MnROEN: Touch key module n Reference oscillator enable control
0: Disable
1: Enable
Bit 4
MnKOEN: Touch key module n Key oscillator enable control
0: Disable
1: Enable
Bit 3
MnK4IO: Touch key module n KEY 4 enable control
MnK4IO
Touch Key Module n – Mn
M0
M1
0: Disable
Bit 2
M3
M4
1: Enable
KEY4
KEY8
KEY12
KEY16
KEY20
BS87B12A-3
√
√
√
—
—
BS87C16A-3
√
√
√
√
—
BS87D20A-3
√
√
√
√
√
M3
M4
MnK3IO: Touch key module n KEY 3 enable control
MnK3IO
Touch Key Module n – Mn
M0
M1
0: Disable
Rev. 1.20
M2
I/O or other functions
M2
I/O or other functions
1: Enable
KEY3
KEY7
KEY11
KEY15
KEY19
BS87B12A-3
√
√
√
—
—
BS87C16A-3
√
√
√
√
—
BS87D20A-3
√
√
√
√
√
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Touch A/D Flash MCU with OCVP
Bit 1
MnK2IO: Touch key module n KEY 2 enable control
MnK2IO
Touch Key Module n – Mn
M0
M1
0: Disable
Bit 0
M2
M3
M4
I/O or other functions
1: Enable
KEY2
KEY6
KEY10
KEY14
KEY18
BS87B12A-3
√
√
√
—
—
BS87C16A-3
√
√
√
√
—
BS87D20A-3
√
√
√
√
√
M3
M4
MnK1IO: Touch key module n KEY 1 enable control
MnK1IO
Touch Key Module n – Mn
M0
M1
0: Disable
M2
I/O or other functions
1: Enable
KEY1
KEY5
KEY9
KEY13
KEY17
BS87B12A-3
√
√
√
—
—
BS87C16A-3
√
√
√
√
—
BS87D20A-3
√
√
√
√
√
Touch Key Operation
When a finger touches or is in proximity to a touch pad, the capacitance of the pad will increase.
By using this capacitance variation to change slightly the frequency of the internal sense oscillator,
touch actions can be sensed by measuring these frequency changes. Using an internal programmable
divider the reference clock is used to generate a fixed time period. By counting a number of
generated clock cycles from the sense oscillator during this fixed time period touch key actions can
be determined.
TKST
MnKOEN
MnROEN
Ha�dwa�e set to “0”
KEY OSC CLK
Refe�en�e OSC CLK
fCFTMCK Ena�le
fCFTMCK (MnDFEN=0)
fCFTMCK (MnDFEN=0)
TKRCOV
Set Tou�h Key inte��upt �equest flag
Touch Key Scan Mode Timing Diagram
Rev. 1.20
131
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
Each touch key module contains four touch key inputs which are shared with logical I/O pins, and
the desired function is selected using register bits. Each touch key has its own independent sense
oscillator. Therefore, there are four sense oscillators within each touch key module.
During this reference clock fixed interval, the number of clock cycles generated by the sense
oscillator is measured, and it is this value that is used to determine if a touch action has been made
or not. At the end of the fixed reference clock time interval a Touch Key interrupt signal will be
generated.
Using the TSCS bit in the TKC0 register can select the module 0 time slot counter as the time slot
counter for all modules. All modules use the same started signal, TKST, in the TKC0 register. The
touch key module 16-bit C/F counter, touch key function 16-bit counter, 5-bit time slot unit period
counter in all modules will be automatically cleared when the TKST bit is cleared to zero, but the 8-bit
programmable time slot counter will not be cleared. The overflow time is setup by user. When the
TKST bit changes from low to high, the 16-bit C/F counter, touch key function 16-bit counter, 5-bit
time slot unit period counter and 8-bit time slot timer counter will be automatically switched on.
The key oscillator and reference oscillator in all modules will be automatically stopped and the 16bit C/F counter, touch key function 16-bit counter, 5-bit time slot unit period counter and 8-bit time
slot timer counter will be automatically switched off when the time slot counter overflows. The
clock source for the time slot counter is sourced from the reference oscillator or fSYS/4 which is
selected using the MnTSS bit in the TKMnC1 register. The reference oscillator and key oscillator
will be enabled by setting the MnROEN bit and MnKOEN bits in the TKMnC1 register.
When the time slot counter in all the touch key modules or in the touch key module 0 overflows,
an actual touch key interrupt will take place. The touch keys mentioned here are the keys which are
enabled.
Each touch key module consists of four touch keys, KEY1 ~ KEY4 are contained in module 0,
KEY5 ~ KEY8 are contained in module 1, KEY9 ~ KEY12 are contained in module 2, etc. Each
touch key module has an identical structure.
Touch Key Interrupt
The touch key only has single interrupt, when the time slot counter in all the touch key modules or
in the touch key module 0 overflows, an actual touch key interrupt will take place. The touch keys
mentioned here are the keys which are enabled. The 16-bit C/F counter, 16-bit counter, 5-bit time
slot unit period counter and 8-bit time slot counter in all modules will be automatically cleared.
The TKCFOV flag which is the 16-bit C/F counter overflow flag will go high when any of the Touch
Key Module 16-bit C/F counter overflows. As this flag will not be automatically cleared, it has to be
cleared by the application program.
The TK16OV flag which is the 16-bit counter overflow flag will go high when the 16-bit counter
overflows. As this flag will not be automatically cleared, it has to be cleared by the application
program. More details regarding the touch key interrupt is located in the interrupt section of the
datasheet.
Programming Considerations
After the relevant registers are setup, the touch key detection process is initiated by changing the
TKST bit from low to high. This will enable and synchronise all relevant oscillators. The TKRCOV
flag which is the time slot counter flag will go high when the counter overflows. When this happens
an interrupt signal will be generated.
When the external touch key size and layout are defined, their related capacitances will then
determine the sensor oscillator frequency.
Rev. 1.20
132
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
Serial Interface Module – SIM
These devices contain a Serial Interface Module, which includes both the four-line SPI interface or
two-line I2C interface types, to allow an easy method of communication with external peripheral
hardware. Having relatively simple communication protocols, these serial interface types allow
the microcontroller to interface to external SPI or I2C based hardware such as sensors, Flash or
EEPROM memory, etc. The SIM interface pins are pin-shared with other I/O pins and therefore the
SIM interface functional pins must first be selected using the corresponding pin-shared function
selection bits. As both interface types share the same pins and registers, the choice of whether the
SPI or I2C type is used is made using the SIM operating mode control bits, named SIM2~SIM0, in
the SIMC0 register. These pull-high resistors of the SIM pin-shared I/O pins are selected using pullhigh control registers when the SIM function is enabled.
It is suggested that the user should not enter the power down mode by executing the "HALT"
instruction during the SIM communication in progress.
SPI Interface
The SPI interface is often used to communicate with external peripheral devices such as sensors,
Flash or EEPROM memory devices, etc. Originally developed by Motorola, the four line SPI
interface is a synchronous serial data interface that has a relatively simple communication protocol
simplifying the programming requirements when communicating with external hardware devices.
The communication is full duplex and operates as a slave/master type, where the devices can be
either master or slave. Although the SPI interface specification can control multiple slave devices
from a single master, these devices provided only one SCS pin. If the master needs to control
multiple slave devices from a single master, the master can use I/O pin to select the slave devices.
SPI Interface Operation
The SPI interface is a full duplex synchronous serial data link. It is a four line interface with pin
names SDI, SDO, SCK and SCS. Pins SDI and SDO are the Serial Data Input and Serial Data
Output lines, SCK is the Serial Clock line and SCS is the Slave Select line. As the SPI interface pins
are pin-shared with normal I/O pins and with the I2C function pins, the SPI interface pins must first
be selected by configuring the pin-shared function selection bits and setting the correct bits in the
SIMC0 and SIMC2 registers. After the desired SPI configuration has been set it can be disabled or
enabled using the SIMEN bit in the SIMC0 register. Communication between devices connected
to the SPI interface is carried out in a slave/master mode with all data transfer initiations being
implemented by the master. The Master also controls the clock signal. As the device only contains
a single SCS pin only one slave device can be utilized. The SCS pin is controlled by software, set
CSEN bit to 1 to enable SCS pin function, set CSEN bit to 0 the SCS pin will be floating state.
The SPI function in this device offers the following features:
• Full duplex synchronous data transfer
• Both Master and Slave modes
• LSB first or MSB first data transmission modes
• Transmission complete flag
• Rising or falling active clock edge
The status of the SPI interface pins is determined by a number of factors such as whether the device
is in the master or slave mode and upon the condition of certain control bits such as CSEN and
SIMEN.
Rev. 1.20
133
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
SPI Maste�
SPI Slave
SCK
SCK
SDO
SDI
SDI
SDO
SCS
SCS
SPI Master/Slave Connection
Data Bus
SIMD
SDI Pin
TX/RX Shift Register
SDO Pin
Clock
Edge/Polarity
Control
CKEG bit
CKPOLB bit
WCOL Flag
TRF Flag
Busy Status
SCK Pin
Clock
Source
Select
fSYS
fSUB
PTM0 CCRP match frequency/2
SCS Pin
ICF Flag
CSEN bit
SPI Block Diagram
SPI Registers
There are three internal registers which control the overall operation of the SPI interface. These are
the SIMD data register and two registers SIMC0 and SIMC2. Note that the SIMC1 register is only
used by the I2C interface.
Bit
Register
Name
7
6
SIMC0
SIM2
SIM1
SIM0
—
SIMC2
D7
D6
CKPOLB
CKEG
MLS
CSEN
SIMD
D7
D6
D5
D4
D3
D2
5
4
3
2
SIMDEB1 SIMDEB0
1
0
SIMEN
SIMICF
WCOL
TRF
D1
D0
SPI Registers List
Rev. 1.20
134
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
• SIMD Register
The SIMD register is used to store the data being transmitted and received. The same register is used
by both the SPI and I2C functions. Before the device writes data to the SPI bus, the actual data to
be transmitted must be placed in the SIMD register. After the data is received from the SPI bus, the
device can read it from the SIMD register. Any transmission or reception of data from the SPI bus
must be made via the SIMD register.
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
×
×
×
×
×
×
×
×
"×": unknown
There are also two control registers for the SPI interface, SIMC0 and SIMC2. Note that the SIMC2
register also has the name SIMA which is used by the I2C function. The SIMC1 register is not used
by the SPI function, only by the I2C function. Register SIMC0 is used to control the enable/disable
function and to set the data transmission clock frequency. Register SIMC2 is used for other control
functions such as LSB/MSB selection, write collision flag, etc.
• SIMC0 Register
Bit
7
6
5
Name
SIM2
SIM1
SIM0
—
R/W
R/W
R/W
R/W
—
R/W
R/W
POR
1
1
1
—
0
0
Bit 7~5
Rev. 1.20
4
3
2
SIMDEB1 SIMDEB0
1
0
SIMEN
SIMICF
R/W
R/W
0
0
SIM2~SIM0: SIM Operating Mode Control
000: SPI master mode; SPI clock is fSYS/4
001: SPI master mode; SPI clock is fSYS/16
010: SPI master mode; SPI clock is fSYS/64
011: SPI master mode; SPI clock is fSUB
100: SPI master mode; SPI clock is PTM0 CCRP match frequency/2
101: SPI slave mode
110: I2C slave mode
111: Non SIM function
These bits setup the overall operating mode of the SIM function. As well as selecting
if the I2C or SPI function, they are used to control the SPI Master/Slave selection and
the SPI Master clock frequency. The SPI clock is a function of the system clock but
can also be chosen to be sourced from PTM0. If the SPI Slave Mode is selected then
the clock will be supplied by an external Master device.
Bit 4
Unimplemented, read as "0"
Bit 3~2
SIMDEB1~SIMDEB0: I2C Debounce Time Selection
The SIMDEB1~SIMDEB0 bits are only used in the I 2C mode and the detailed
definition is described in the I2C interface section.
135
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
Bit 1
SIMEN: SIM Enable Control
0: Disable
1: Enable
The bit is the overall on/off control for the SIM interface. When the SIMEN bit is
cleared to zero to disable the SIM interface, the SDI, SDO, SCK and SCS, or SDA and
SCL lines will lose their SPI or I2C function and the SIM operating current will be
reduced to a minimum value. When the bit is high the SIM interface is enabled. The
SIM configuration option must have first enabled the SIM interface for this bit to be
effective. If the SIM is configured to operate as an SPI interface via the SIM2~SIM0
bits, the contents of the SPI control registers will remain at the previous settings when
the SIMEN bit changes from low to high and should therefore be first initialised by
the application program. If the SIM is configured to operate as an I2C interface via the
SIM2~SIM0 bits and the SIMEN bit changes from low to high, the contents of the I2C
control bits such as HTX and TXAK will remain at the previous settings and should
therefore be first initialised by the application program while the relevant I2C flags
such as HCF, HAAS, HBB, SRW and RXAK will be set to their default states.
Bit 0
SIMICF: SIM SPI slave mode Incomplete Transfer Flag
0: SIM SPI slave mode incomplete condition not occurred
1: SIM SPI slave mode incomplete condition occurred
This bit is only available when the SIM is configured to operate in an SPI slave mode.
If the SPI operates in the slave mode with the SIMEN and CSEN bits both being set
to 1 but the SCS line is pulled high by the external master device before the SPI data
transfer is completely finished, the SIMICF bit will be set to 1 together with the TRF
bit. When this condition occurs, the corresponding interrupt will occur if the interrupt
function is enabled. However, the TRF bit will not be set to 1 if the SIMICF bit is set
to 1 by software application program.
• SIMC2 Register
Rev. 1.20
Bit
7
6
5
4
3
2
1
0
Name
D7
D6
CKPOLB
CKEG
MLS
CSEN
WCOL
TRF
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
0
0
0
0
0
0
0
Bit 7~6
Undefined bits
These bits can be read or written by the application program.
Bit 5
CKPOLB: SPI clock line base condition selection
0: The SCK line will be high when the clock is inactive.
1: The SCK line will be low when the clock is inactive.
The CKPOLB bit determines the base condition of the clock line, if the bit is high,
then the SCK line will be low when the clock is inactive. When the CKPOLB bit is
low, then the SCK line will be high when the clock is inactive.
Bit 4
CKEG: SPI SCK clock active edge type selection
CKPOLB=0
0: SCK is high base level and data capture at SCK rising edge
1: SCK is high base level and data capture at SCK falling edge
CKPOLB=1
0: SCK is low base level and data capture at SCK falling edge
1: SCK is low base level and data capture at SCK rising edge
The CKEG and CKPOLB bits are used to setup the way that the clock signal outputs
and inputs data on the SPI bus. These two bits must be configured before data transfer
is executed otherwise an erroneous clock edge may be generated. The CKPOLB bit
determines the base condition of the clock line, if the bit is high, then the SCK line
will be low when the clock is inactive. When the CKPOLB bit is low, then the SCK
line will be high when the clock is inactive. The CKEG bit determines active clock
edge type which depends upon the condition of CKPOLB bit.
136
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
Bit 3
MLS: SPI data shift order
0: LSB first
1: MSB first
This is the data shift select bit and is used to select how the data is transferred, either
MSB or LSB first. Setting the bit high will select MSB first and low for LSB first.
Bit 2
CSEN: SPI SCS pin control
0: Disable
1: Enable
The CSEN bit is used as an enable/disable for the SCS pin. If this bit is low, then the
SCS pin will be disabled and placed into I/O pin or other pin-shared functions. If the
bit is high, the SCS pin will be enabled and used as a select pin.
Bit 1
WCOL: SPI write collision flag
0: No collision
1: Collision
The WCOL flag is used to detect whether a data collision has occurred or not. If this
bit is high, it means that data has been attempted to be written to the SIMD register
during a data transfer operation. This writing operation will be ignored if data is being
transferred. This bit can be cleared by the application program.
Bit 0
TRF: SPI Transmit/Receive complete flag
0: SPI data is being transferred
1: SPI data transfer is completed
The TRF bit is the Transmit/Receive Complete flag and is set to 1 automatically when
an SPI data transfer is completed, but must cleared to 0 by the application program. It
can be used to generate an interrupt.
SPI Communication
After the SPI interface is enabled by setting the SIMEN bit high, then in the Master Mode, when
data is written to the SIMD register, transmission/reception will begin simultaneously. When the
data transfer is complete, the TRF flag will be set automatically, but must be cleared using the
application program. In the Slave Mode, when the clock signal from the master has been received,
any data in the SIMD register will be transmitted and any data on the SDI pin will be shifted into
the SIMD register. The master should output a SCS signal to enable the slave devices before a
clock signal is provided. The slave data to be transferred should be well prepared at the appropriate
moment relative to the SCS signal depending upon the configurations of the CKPOLB bit and CKEG
bit. The accompanying timing diagram shows the relationship between the slave data and SCS signal
for various configurations of the CKPOLB and CKEG bits.
The SPI will continue to function in specific IDLE Mode if the clock source used by the SPI
interface is still active.
Rev. 1.20
137
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
SIMEN=1� CSEN=0 (Exte�nal Pull-high)
SCS
SIMEN� CSEN=1
SCK (CKPOLB=1� CKEG=0)
SCK (CKPOLB=0� CKEG=0)
SCK (CKPOLB=1� CKEG=1)
SCK (CKPOLB=0� CKEG=1)
SDO (CKEG=0)
D7/D0
D�/D1
D�/D2
D4/D3
D3/D4 D2/D�
D1/D�
D0/D7
SDO (CKEG=1)
D7/D0
D�/D1
D�/D2
D4/D3
D3/D4 D2/D�
D1/D�
D0/D7
SDI Data Captu�e
W�ite to SIMD
SPI Master Mode Timing
SCS
SCK (CKPOLB=1)
SCK (CKPOLB=0)
SDO
D7/D0
D�/D1
D�/D2
D4/D3
D3/D4
D2/D�
D1/D�
D0/D7
D1/D�
D0/D7
SDI Data Captu�e
W�ite to SIMD
(SDO does not �hange until fi�st SCK edge)
SPI Slave Mode Timing – CKEG=0
SCS
SCK (CKPOLB=1)
SCK (CKPOLB=0)
SDO
D7/D0
D�/D1
D�/D2
D4/D3
D3/D4
D2/D�
SDI Data Captu�e
W�ite to SIMD
(SDO �hanges as soon as w�iting o��u�s; SDO is floating if SCS=1)
Note: Fo� SPI slave �ode� if SIMEN=1 and CSEN=0� SPI is always
ena�led and igno�es the SCS level.
SPI Slave Mode Timing – CKEG=1
Rev. 1.20
138
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
SPI T�ansfe�
Maste�
Maste� o� Slave
?
A
W�ite Data
into SIMD
Clea� WCOL
Slave
Y
SIM[2:0]=000� 001�
010� 011 o� 100
WCOL=1?
SIM[2:0]=101
N
T�ans�ission
�o�pleted?
(TRF=1?)
N
Configu�e CKPOLB�
CKEG� CSEN and MLS
Y
SIMEN=1
Read Data
f�o� SIMD
A
Clea� TRF
T�ansfe�
finished?
N
Y
END
SPI Transfer Control Flow Chart
I2C Interface
The I 2C interface is used to communicate with external peripheral devices such as sensors,
EEPROM memory etc. Originally developed by Philips, it is a two line low speed serial interface
for synchronous serial data transfer. The advantage of only two lines for communication, relatively
simple communication protocol and the ability to accommodate multiple devices on the same bus
has made it an extremely popular interface type for many applications.
VDD
SDA
SCL
Devi�e
Slave
Devi�e
Maste�
Devi�e
Slave
I2C Master/Slave Bus Connection
Rev. 1.20
139
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
I2C interface Operation
The I2C serial interface is a two line interface, a serial data line, SDA, and serial clock line, SCL. As
many devices may be connected together on the same bus, their outputs are both open drain types.
For this reason it is necessary that external pull-high resistors are connected to these outputs. Note
that no chip select line exists, as each device on the I2C bus is identified by a unique address which
will be transmitted and received on the I2C bus.
When two devices communicate with each other on the bidirectional I2C bus, one is known as the
master device and one as the slave device. Both master and slave can transmit and receive data;
however, it is the master device that has overall control of the bus. For these devices, which only
operate in slave mode, there are two methods of transferring data on the I2C bus, the slave transmit
mode and the slave receive mode. The pull-high control function pin-shared with the SCL or SDA
pin is still applicable even if the I2C interface is activated and the related internal pull-up resistor
could be controlled by its corresponding pull-up control register.
Data Bus
Add�ess Mat�h
SIMTOEN
fSUB
fSYS
SCL Pin
SDA Pin
De�oun�e
Ci��uit�y
SIMDEB1
&
SIMDEB0
Ti�e-out
Cont�ol
I2C Data Registe�
(SIMD)
Slave Add�ess Registe�
(SIMA)
SIMTOF
Add�ess Add�ess Mat�h
Co�pa�ato� HAAS Bit
Di�e�tion Cont�ol
HTX Bit
SIMTOF Bit
Data in
M
U
X
I2C Inte��upt
Shift Registe�
Read/W�ite Slave
SRW Bit
Data out
TXAK
T�ans�it/
Re�eive
Cont�ol Unit
8-�it Data Co�plete
Dete�t Sta�t o� Stop
HCF Bit
HBB Bit
I2C Block Diagram
START signal
f�o� Maste�
Send slave add�ess
and R/W �it f�o� Maste�
A�knowledge
f�o� slave
Send data �yte
f�o� Maste�
A�knowledge
f�o� slave
STOP signal
f�o� Maste�
Rev. 1.20
140
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
The SIMDEB1 and SIMDEB0 bits determine the debounce time of the I2C interface. This uses
the system clock to in effect add a debounce time to the external clock to reduce the possibility
of glitches on the clock line causing erroneous operation. The debounce time, if selected, can be
chosen to be either 2 or 4 system clocks. To achieve the required I2C data transfer speed, there
exists a relationship between the system clock, fSYS, and the I2C debounce time. For either the I2C
Standard or Fast mode operation, users must take care of the selected system clock frequency and
the configured debounce time to match the criterion shown in the following table.
I2C Debounce Time Selection
I2C Standard Mode (100kHz)
No Devounce
fSYS > 2 MHz
fSYS > 5 MHz
2 system clock debounce
fSYS > 4 MHz
fSYS > 10 MHz
fSYS > 8 MHz
fSYS > 20 MHz
4 system clock debounce
I2C Fast Mode (400kHz)
I C Minimum fSYS Frequency
2
I2C Registers
There are three control registers associated with the I2C bus, SIMC0, SIMC1 and SIMTOC, one
slave address register, SIMA, and one data register, SIMD. Any transmission or reception of data
from the I2C bus must be made via the SIMD register. Bit SIMEN and bits SIM2~SIM0 in register
SIMC0 are used by the I2C interface as well as the SPI interface. The SIMTOC register is used for
the I2C time-out control.
Note that the SIMA register also has the name SIMC2 which is used by the SPI function.
Bit
Register
Name
7
6
5
4
SIMC0
SIM2
SIM1
SIM0
—
SIMC1
HCF
HAAS
HBB
HTX
TXAK
SIMA
IICA6
IICA5
IICA4
IICA3
IICA2
SIMD
D7
D6
D5
D4
D3
D2
SIMTOC SIMTOEN
3
2
1
0
SIMEN
SIMICF
SRW
IAMWU
RXAK
IICA1
IICA0
—
D1
D0
SIMDEB1 SIMDEB0
SIMTOF SIMTOS5 SIMTOS4 SIMTOS3 SIMTOS2 SIMTOS1 SIMTOS0
I2C Registers List
• SIMD Register
The SIMD register is used to store the data being transmitted and received. The same register is used
by both the SPI and I2C functions. Before the device writes data to the I2C bus, the actual data to
be transmitted must be placed in the SIMD register. After the data is received from the I2C bus, the
device can read it from the SIMD register. Any transmission or reception of data from the I2C bus
must be made via the SIMD register.
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
×
×
×
×
×
×
×
×
"×": unknown
Rev. 1.20
141
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
• SIMA Register
The SIMA register is also used by the SPI interface but has the name SIMC2. The SIMA register is
the location where the 7-bit slave address of the slave device is stored. Bits 7~1 of the SIMA register
define the device slave address. Bit 0 is not implemented.
When a master device, which is connected to the I2C bus, sends out an address, which matches the
slave address in the SIMA register, the slave device will be selected. Note that the SIMA register is
the same register address as SIMC2 which is used by the SPI interface.
Bit
7
6
5
4
3
2
1
0
Name
IICA6
IICA5
IICA4
IICA3
IICA2
IICA1
IICA0
—
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
—
POR
×
×
×
×
×
×
×
—
"×": unknown
Bit 7~1
IICA6~IICA0: I2C slave address
IICA6~IICA0 is the I2C slave address bit 6 ~ bit 0
Bit 0
Unimplemented, read as "0".
There are also two control registers for the I2C interface, SIMC0 and SIMC1. The register SIMC0
is used to control the enable/disable function and to set the data transmission clock frequency. The
SIMC1 register contains the relevant flags which are used to indicate the I2C communication status.
• SIMC0 Register
Rev. 1.20
Bit
7
6
5
4
Name
SIM2
SIM1
SIM0
—
3
R/W
R/W
R/W
R/W
—
R/W
POR
1
1
1
—
0
2
1
0
SIMEN
SIMICF
R/W
R/W
R/W
0
0
0
SIMDEB1 SIMDEB0
Bit 7~5
SIM2~SIM0: SIM Operating Mode Control
000: SPI master mode; SPI clock is fSYS /4
001: SPI master mode; SPI clock is fSYS /16
010: SPI master mode; SPI clock is fSYS /64
011: SPI master mode; SPI clock is fSUB
100: SPI master mode; SPI clock is PTM0 CCRP match frequency/2
101: SPI slave mode
110: I2C slave mode
111: Non SIM function
These bits setup the overall operating mode of the SIM function. As well as selecting
if the I2C or SPI function, they are used to control the SPI Master/Slave selection and
the SPI Master clock frequency. The SPI clock is a function of the system clock but
can also be chosen to be sourced from PTM0. If the SPI Slave Mode is selected then
the clock will be supplied by an external Master device.
Bit 4
Unimplemented, read as "0"
Bit 3~2
SIMDEB1~SIMDEB0: I2C Debounce Time Selection
00: No debounce
01: 2 system clock debounce
1x: 4 system clock debounce
These bits are used to select the I2C debounce time when the SIM is configured as the
I2C interface function by setting the SIM2~SIM0 bits to "110".
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Bit 1
SIMEN: SIM Enable Control
0: Disable
1: Enable
The bit is the overall on/off control for the SIM interface. When the SIMEN bit is
cleared to zero to disable the SIM interface, the SDI, SDO, SCK and SCS, or SDA and
SCL lines will lose their SPI or I2C function and the SIM operating current will be
reduced to a minimum value. When the bit is high the SIM interface is enabled. The
SIM configuration option must have first enabled the SIM interface for this bit to be
effective.If the SIM is configured to operate as an SPI interface via the SIM2~SIM0
bits, the contents of the SPI control registers will remain at the previous settings when
the SIMEN bit changes from low to high and should therefore be first initialised by
the application program. If the SIM is configured to operate as an I2C interface via the
SIM2~SIM0 bits and the SIMEN bit changes from low to high, the contents of the I2C
control bits such as HTX and TXAK will remain at the previous settings and should
therefore be first initialised by the application program while the relevant I2C flags
such as HCF, HAAS, HBB, SRW and RXAK will be set to their default states.
Bit 0
SIMICF: SIM SPI Incomplete Flag
The SIMICF bit is only used in the SPI mode and the detailed definition is described
in the SPI interface section.
• SIMC1 Register
Rev. 1.20
Bit
7
6
5
4
3
2
1
0
Name
HCF
HAAS
HBB
HTX
TXAK
SRW
IAMWU
RXAK
R/W
R
R
R
R/W
R/W
R/W
R/W
R
POR
1
0
0
0
0
0
0
1
Bit 7
HCF: I2C Bus data transfer completion flag
0: Data is being transferred
1: Completion of an 8-bit data transfer
The HCF flag is the data transfer flag. This flag will be zero when data is being
transferred. Upon completion of an 8-bit data transfer the flag will go high and an
interrupt will be generated.
Bit 6
HAAS: I2C Bus data transfer completion flag
0: Not address match
1: Address match
The HAAS flag is the address match flag. This flag is used to determine if the slave
device address is the same as the master transmit address. If the addresses match then
this bit will be high, if there is no match then the flag will be low.
Bit 5
HBB: I2C Bus busy flag
0: I2C Bus is not busy
1: I2C Bus is busy
The HBB flag is the I2C busy flag. This flag will be "1" when the I2C bus is busy which
will occur when a START signal is detected. The flag will be set to "0" when the bus is
free which will occur when a STOP signal is detected.
Bit 4
HTX: I2C slave device transmitter/receiver selection
0: Slave device is the receiver
1: Slave device is the transmitter
Bit 3
TXAK: I2C bus transmit acknowledge flag
0: Slave send acknowledge flag
1: Slave does not send acknowledge flag
The TXAK bit is the transmit acknowledge flag. After the slave device receipt of 8-bits
of data, this bit will be transmitted to the bus on the 9th clock from the slave device.
The slave device must always set TXAK bit to "0" before further data is received.
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Bit 2
SRW: I2C slave read/write flag
0: Slave device should be in receive mode
1: Slave device should be in transmit mode
The SRW flag is the I 2C Slave Read/Write flag. This flag determines whether
the master device wishes to transmit or receive data from the I2C bus. When the
transmitted address and slave address is match, that is when the HAAS flag is set high,
the slave device will check the SRW flag to determine whether it should be in transmit
mode or receive mode. If the SRW flag is high, the master is requesting to read data
from the bus, so the slave device should be in transmit mode. When the SRW flag
is zero, the master will write data to the bus, therefore the slave device should be in
receive mode to read this data.
Bit 1
IAMWU: I2C Address Match Wake-Up control
0: Disable
1: Enable – must be cleared by the application program after wake-up
This bit should be set to 1 to enable the I2C address match wake up from the SLEEP
or IDLE Mode. If the IAMWU bit has been set before entering either the SLEEP or
IDLE mode to enable the I2C address match wake up, then this bit must be cleared by
the application program after wake-up to ensure correction device operation.
Bit 0
RXAK: I2C bus receive acknowledge flag
0: Slave receives acknowledge flag
1: Slave does not receive acknowledge flag
The RXAK flag is the receiver acknowledge flag. When the RXAK flag is "0", it
means that a acknowledge signal has been received at the 9th clock, after 8 bits of data
have been transmitted. When the slave device in the transmit mode, the slave device
checks the RXAK flag to determine if the master receiver wishes to receive the next
byte. The slave transmitter will therefore continue sending out data until the RXAK
flag is "1". When this occurs, the slave transmitter will release the SDA line to allow
the master to send a STOP signal to release the I2C Bus.
I2C Bus Communication
Communication on the I2C bus requires four separate steps, a START signal, a slave device address
transmission, a data transmission and finally a STOP signal. When a START signal is placed on
the I2C bus, all devices on the bus will receive this signal and be notified of the imminent arrival of
data on the bus. The first seven bits of the data will be the slave address with the first bit being the
MSB. If the address of the slave device matches that of the transmitted address, the HAAS bit in the
SIMC1 register will be set and an I2C interrupt will be generated. After entering the interrupt service
routine, the slave device must first check the condition of the HAAS and SIMTOF bits to determine
whether the interrupt source originates from an address match, 8-bit data transfer completion or
I2C bus time-out occurrence. During a data transfer, note that after the 7-bit slave address has been
transmitted, the following bit, which is the 8th bit, is the read/write bit whose value will be placed in
the SRW bit. This bit will be checked by the slave device to determine whether to go into transmit or
receive mode. Before any transfer of data to or from the I2C bus, the microcontroller must initialise
the bus; the following are steps to achieve this:
• Step 1
Set the SIM2~SIM0 bits to "110" and SIMEN bit to "1" in the SIMC0 register to enable the I2C
bus.
• Step 2
Write the slave address of the device to the I2C bus address register SIMA.
• Step 3
Set the SIME bit in the interrupt control register to enable the SIM interrupt.
Rev. 1.20
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Start
Set SIM[2:0]=110
Set SIMEN
Write Slave
Address to SIMA
I2C Bus
Interrupt=?
Clear SIMEN
Poll SIMF to decide when
to go to I2C Bus ISR
Set SIME
Wait for Interrupt
Goto Main
Program
Goto Main
Program
I2C Bus Inisialisation Flow Chart
I2C Bus Start Signal
The START signal can only be generated by the master device connected to the I2C bus and not by
the slave device. This START signal will be detected by all devices connected to the I2C bus. When
detected, this indicates that the I2C bus is busy and therefore the HBB bit will be set. A START
condition occurs when a high to low transition on the SDA line takes place when the SCL line
remains high.
I2C Slave Address
The transmission of a START signal by the master will be detected by all devices on the I2C bus.
To determine which slave device the master wishes to communicate with, the address of the slave
device will be sent out immediately following the START signal. All slave devices, after receiving
this 7-bit address data, will compare it with their own 7-bit slave address. If the address sent out by
the master matches the internal address of the microcontroller slave device, then an internal I2C bus
interrupt signal will be generated. The next bit following the address, which is the 8th bit, defines the
read/write status and will be saved to the SRW bit of the SIMC1 register. The slave device will then
transmit an acknowledge bit, which is a low level, as the 9th bit. The slave device will also set the
status flag HAAS when the addresses match.
As an I2C bus interrupt can come from three sources, when the program enters the interrupt
subroutine, the HAAS and SIMTOF bits should be examined to see whether the interrupt source has
come from a matching slave address, the completion of a data byte transfer or the I2C bus time-out
occurrence. When a slave address is matched, the devices must be placed in either the transmit mode
and then write data to the SIMD register, or in the receive mode where it must implement a dummy
read from the SIMD register to release the SCL line.
I2C Bus Read/Write Signal
The SRW bit in the SIMC1 register defines whether the slave device wishes to read data from the
I2C bus or write data to the I2C bus. The slave device should examine this bit to determine if it is to
be a transmitter or a receiver. If the SRW flag is "1" then this indicates that the master device wishes
to read data from the I2C bus, therefore the slave device must be setup to send data to the I2C bus as
a transmitter. If the SRW flag is "0" then this indicates that the master wishes to send data to the I2C
bus, therefore the slave device must be setup to read data from the I2C bus as a receiver.
Rev. 1.20
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I2C Bus Slave Address Acknowledge Signal
After the master has transmitted a calling address, any slave device on the I 2C bus, whose
own internal address matches the calling address, must generate an acknowledge signal. The
acknowledge signal will inform the master that a slave device has accepted its calling address. If no
acknowledge signal is received by the master then a STOP signal must be transmitted by the master
to end the communication. When the HAAS flag is high, the addresses have matched and the slave
device must check the SRW flag to determine if it is to be a transmitter or a receiver. If the SRW flag
is high, the slave device should be setup to be a transmitter so the HTX bit in the SIMC1 register
should be set to "1". If the SRW flag is low, then the microcontroller slave device should be setup as
a receiver and the HTX bit in the SIMC1 register should be set to "0".
I2C Bus Data and Acknowledge Signal
The transmitted data is 8-bits wide and is transmitted after the slave device has acknowledged
receipt of its slave address. The order of serial bit transmission is the MSB first and the LSB last.
After receipt of 8-bits of data, the receiver must transmit an acknowledge signal, level "0", before
it can receive the next data byte. If the slave transmitter does not receive an acknowledge bit signal
from the master receiver, then the slave transmitter will release the SDA line to allow the master
to send a STOP signal to release the I2C Bus. The corresponding data will be stored in the SIMD
register. If setup as a transmitter, the slave device must first write the data to be transmitted into the
SIMD register. If setup as a receiver, the slave device must read the transmitted data from the SIMD
register.
When the slave receiver receives the data byte, it must generate an acknowledge bit, known as
TXAK, on the 9th clock. The slave device, which is setup as a transmitter will check the RXAK bit
in the SIMC1 register to determine if it is to send another data byte, if not then it will release the
SDA line and await the receipt of a STOP signal from the master.
SCL
Slave Add�ess
Sta�t
1
0
1
SDA
1
0
1
SRW
ACK
1
0
0
Data
SCL
1
0
0
1
0
ACK
1
0
Stop
0
SDA
S=Sta�t (1 �it)
SA=Slave Add�ess (7 �its)
SR=SRW �it (1 �it)
M=Slave devi�e send a�knowledge �it (1 �it)
D=Data (8 �its)
A=ACK (RXAK �it fo� t�ans�itte�� TXAK �it fo� �e�eive�� 1 �it)
P=Stop (1 �it)
S
SA SR M
D
A
D
A
……
S
SA SR M
D
A
D
A
……
P
Note: *When a slave address is matched, the devices must be placed in either the transmit mode
and then write data to the SIMD register, or in the receive mode where it must implement a
dummy read from the SIMD register to release the SCL line.
I2C Communication Timing Diagram
Rev. 1.20
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Sta�t
No
No
No
HTX=1?
Yes
HAAS=1?
Yes
SIMTOF=1?
Yes
Yes
SET SIMTOEN
CLR SIMTOF
SRW=1?
No
RETI
Read f�o� SIMD to
�elease SCL Line
RETI
Yes
SET HTX
CLR HTX
CLR TXAK
W�ite data to SIMD to
�elease SCL Line
Du��y �ead f�o� SIMD
to �elease SCL Line
RETI
RETI
RXAK=1?
No
CLR HTX
CLR TXAK
W�ite data to SIMD to
�elease SCL Line
Du��y �ead f�o� SIMD
to �elease SCL Line
RETI
RETI
I2C Bus ISR Flow Chart
I2C Time-out Control
In order to reduce the I2C lockup problem due to reception of erroneous clock sources, a time-out
function is provided. If the clock source connected to the I2C bus is not received for a while, then the
I2C circuitry and registers will be reset after a certain time-out period. The time-out counter starts
to count on an I2C bus "START" & "address match" condition, and is cleared by an SCL falling
edge. Before the next SCL falling edge arrives, if the time elapsed is greater than the time-out period
specified by the SIMTOC register, then a time-out condition will occur. The time-out function will
stop when an I2C "STOP" condition occurs.
Rev. 1.20
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SCL
Sta�t
Slave Add�ess
1
SDA
0
1
1
0
1
SRW
ACK
1
0
0
I2C ti�e-out
�ounte� sta�t
Stop
SCL
1
0
0
1
0
1
0
0
SDA
I2C ti�e-out �ounte� �eset
on SCL negative t�ansition
I2C Time-out
When an I2C time-out counter overflow occurs, the counter will stop and the SIMTOEN bit will
be cleared to zero and the SIMTOF bit will be set high to indicate that a time-out condition has
occurred. The time-out condition will also generate an interrupt which uses the I2C interrupt vector.
When an I2C time-out occurs, the I2C internal circuitry will be reset and the registers will be reset
into the following condition:
Register
After I2C Time-out
SIMD, SIMA, SIMC0
No change
SIMC1
Reset to POR condition
I2C Register after Time-out
The SIMTOF flag can be cleared by the application program. There are 64 time-out period selections
which can be selected using the SIMTOS bits in the SIMTOC register. The time-out duration is
calculated by the formula: ((1~64)×(32/fSUB)). This gives a time-out period which ranges from about
1ms to 64ms.
• SIMTOC Register
Rev. 1.20
Bit
7
6
5
4
3
2
1
0
Name
SIMTOEN
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
0
0
0
0
0
0
0
SIMTOF SIMTOS5 SIMTOS4 SIMTOS3 SIMTOS2 SIMTOS1 SIMTOS0
Bit 7
SIMTOEN: SIM I C Time-out control
0: Disable
1: Enable
Bit 6
SIMTOF: SIM I2C Time-out flag
0: No time-out occurred
1: Time-out occurred
This bit is set high by the I2C time-out circuitry and cleared to zero by the application
program.
Bit 5~0
SIMTOS5~SIMTOS0: SIM I2C Time-out period selection
I2C Time-out clock source is fSUB/32
I2C Time-out period is equal to (SIMTOS[5:0]+1)×(32/fSUB)
2
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UART Interface
These devices contain an integrated full-duplex asynchronous serial communications UART
interface that enables communication with external devices that contain a serial interface. The
UART function has many features and can transmit and receive data serially by transferring a frame
of data with eight or nine data bits per transmission as well as being able to detect errors when the
data is overwritten or incorrectly framed. The UART function possesses its own internal interrupt
which can be used to indicate when a reception occurs or when a transmission terminates.
The integrated UART function contains the following features:
• Full-duplex, asynchronous communication
• 8 or 9 bits character length
• Even, odd or no parity options
• One or two stop bits
• Baud rate generator with 8-bit prescaler
• Parity, framing, noise and overrun error detection
• Support for interrupt on address detect (last character bit=1)
• Separately enabled transmitter and receiver
• 2-byte Deep FIFO Receive Data Buffer
• RX pin wake-up function
• Transmit and receive interrupts
• Interrupts can be initialized by the following conditions:
♦♦
Transmitter Empty
♦♦
Transmitter Idle
♦♦
Receiver Full
♦♦
Receiver Overrun
♦♦
Address Mode Detect
T�ans�itte� Shift Registe� (TSR)
MSB ………………………… LSB
TX Pin
TX Registe� (TXR)
RX Pin
Re�eive� Shift Registe� (RSR)
MSB ………………………… LSB
RX Registe� (RXR)
Buffe�
Baud Rate
Gene�ato�
fSYS
Data to �e t�ans�itted
Data �e�eived
MCU Data Bus
UART Data Transfer Block Diagram
UART External Pins
To communicate with an external serial interface, the internal UART has two external pins known
as TX and RX. The TX and RX pins are the UART transmitter and receiver pins respectively. Along
with the UARTEN, TXEN and RXEN bits, if set, will automatically setup the TX and RX pins to
their respective TX output and RX input conditions and disable any pull-high resistor option which
may exist on the TX and RX pins. When the TX or RX pin function is disabled by clearing the
UARTEN, TXEN or RXEN bit, the TX or RX pin will be used as a general purpose I/O or other pinshared functional pin.
Rev. 1.20
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UART Data Transfer Scheme
The above diagram shows the overall data transfer structure arrangement for the UART interface.
The actual data to be transmitted from the MCU is first transferred to the TXR register by the
application program. The data will then be transferred to the Transmit Shift Register from where it
will be shifted out, LSB first, onto the TX pin at a rate controlled by the Baud Rate Generator. Only
the TXR register is mapped onto the MCU Data Memory, the Transmit Shift Register is not mapped
and is therefore inaccessible to the application program.
Data to be received by the UART is accepted on the external RX pin, from where it is shifted in,
LSB first, to the Receiver Shift Register at a rate controlled by the Baud Rate Generator. When
the shift register is full, the data will then be transferred from the shift register to the internal RXR
register, where it is buffered and can be manipulated by the application program. Only the RXR
register is mapped onto the MCU Data Memory, the Receiver Shift Register is not mapped and is
therefore inaccessible to the application program.
It should be noted that the actual register for data transmission and reception, although referred to
in the text, and in application programs, as separate TXR and RXR registers, only exists as a single
shared register in the Data Memory. This shared register known as the TXR_RXR register is used
for both data transmission and data reception.
UART Status and Control Registers
There are five control registers associated with the UART function. The USR, UCR1 and UCR2
registers control the overall function of the UART, while the BRG register controls the Baud rate.
The actual data to be transmitted and received on the serial interface is managed through the TXR_
RXR data registers.
Bit
Register
Name
7
6
5
4
3
2
1
0
USR
PERR
NF
FERR
OERR
RIDLE
RXIF
TIDLE
TXIF
UCR1
UARTEN
BNO
PREN
PRT
STOPS
TXBRK
RX8
TX8
UCR2
TXEN
RXEN
BRGH
ADDEN
WAKE
RIE
TIIE
TEIE
TXR_RXR
TXRX7
TXRX6
TXRX5
TXRX4
TXRX3
TXRX2
TXRX1
TXRX0
BRG
BRG7
BRG6
BRG5
BRG4
BRG3
BRG2
BRG1
BRG0
UART Registers List
USR Register
The USR register is the status register for the UART, which can be read by the program to
determine the present status of the UART. All flags within the USR register are read only and further
explanations are given below.
Bit
7
6
5
4
3
2
1
0
Name
PERR
NF
FERR
OERR
RIDLE
RXIF
TIDLE
TXIF
R/W
R
R
R
R
R
R
R
R
POR
0
0
0
0
1
0
1
1
Bit 7
Rev. 1.20
PERR: Parity error flag
0: No parity error is detected
1: Parity error is detected
The PERR flag is the parity error flag. When this read only flag is "0", it indicates a
parity error has not been detected. When the flag is "1", it indicates that the parity of
the received word is incorrect. This error flag is applicable only if Parity mode (odd or
even) is selected. The flag can also be cleared by a software sequence which involves
a read to the status register USR followed by an access to the TXR_RXR data register.
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Rev. 1.20
Bit 6
NF: Noise flag
0: No noise is detected
1: Noise is detected
The NF flag is the noise flag. When this read only flag is "0", it indicates no noise
condition. When the flag is "1", it indicates that the UART has detected noise on the
receiver input. The NF flag is set during the same cycle as the RXIF flag but will not
be set in the case of as overrun. The NF flag can be cleared by a software sequence
which will involve a read to the status register USR followed by an access to the
TXR_RXR data register.
Bit 5
FERR: Framing error flag
0: No framing error is detected
1: Framing error is detected
The FERR flag is the framing error flag. When this read only flag is "0", it indicates
that there is no framing error. When the flag is "1", it indicates that a framing error
has been detected for the current character. The flag can also be cleared by a software
sequence which will involve a read to the status register USR followed by an access to
the TXR_RXR data register.
Bit 4
OERR: Overrun error flag
0: No overrun error is detected
1: Overrun error is detected
The OERR flag is the overrun error flag which indicates when the receiver buffer has
overflowed. When this read only flag is "0", it indicates that there is no overrun error.
When the flag is "1", it indicates that an overrun error occurs which will inhibit further
transfers to the TXR_RXR receive data register. The flag is cleared by a software
sequence, which is a read to the status register USR followed by an access to the
TXR_RXR data register.
Bit 3
RIDLE: Receiver status
0: data reception is in progress (data being received)
1: no data reception is in progress (receiver is idle)
The RIDLE flag is the receiver status flag. When this read only flag is "0", it indicates
that the receiver is between the initial detection of the start bit and the completion of
the stop bit. When the flag is "1", it indicates that the receiver is idle. Between the
completion of the stop bit and the detection of the next start bit, the RIDLE bit is "1"
indicating that the UART receiver is idle and the RX pin stays in logic high condition.
Bit 2
RXIF: Receive TXR_RXR data register status
0: TXR_RXR data register is empty
1: TXR_RXR data register has available data
The RXIF flag is the receive data register status flag. When this read only flag is "0",
it indicates that the TXR_RXR read data register is empty. When the flag is "1", it
indicates that the TXR_RXR read data register contains new data. When the contents
of the shift register are transferred to the TXR_RXR register, an interrupt is generated
if RIE=1 in the UCR2 register. If one or more errors are detected in the received word,
the appropriate receive-related flags NF, FERR, and/or PERR are set within the same
clock cycle. The RXIF flag will eventually be cleared when the USR register is read
with RXIF set, followed by a read from the TXR_RXR register, and if the TXR_RXR
register has no more new data available.
Bit 1
TIDLE: Transmission status
0: data transmission is in progress (data being transmitted)
1: no data transmission is in progress (transmitter is idle)
The TIDLEn flag is known as the transmission complete flag. When this read only
flag is "0", it indicates that a transmission is in progress. This flag will be set to "1"
when the TXIF flag is "1" and when there is no transmit data or break character being
transmitted. When TIDLE is equal to 1, the TX pin becomes idle with the pin state
in logic high condition. The TIDLE flag is cleared by reading the USR register with
TIDLE set and then writing to the TXR_RXR register. The flag is not generated when
a data character or a break is queued and ready to be sent.
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Bit 0
TXIF: Transmit TXR data register status
0: character is not transferred to the transmit shift register
1: character has transferred to the transmit shift register (TXR_RXR data register is
empty)
The TXIF flag is the transmit data register empty flag. When this read only flag is "0",
it indicates that the character is not transferred to the transmitter shift register. When
the flag is "1", it indicates that the transmitter shift register has received a character
from the TXR_RXR data register. The TXIF flag is cleared by reading the UART
status register (USR) with TXIF set and then writing to the TXR_RXR data register.
Note that when the TXEN bit is set, the TXIF flag bit will also be set since the transmit
data register is not yet full.
UCR1 Register
The UCR1 register together with the UCR2 register are the UART control registers that are used
to set the various options for the UART function such as overall on/off control, parity control, data
transfer bit length, etc. Further explanation on each of the bits is given below.
Bit
7
6
5
4
3
2
1
0
Name
UARTEN
BNO
PREN
PRT
STOPS
TXBRK
RX8
TX8
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R
W
POR
0
0
0
0
0
0
×
0
"×": unknown
Rev. 1.20
Bit 7
UARTEN: UART function enable control
0: Disable UART; TX and RX pins are as I/O or other pin-shared functional pins
1: Enable UART; TX and RX pins function as UART pins
The UARTEN bit is the UART enable bit. When this bit is equal to "0", the UART
will be disabled and the RX pin as well as the TX pin will be as the general purpose
I/O or other pin-shared functional pins. When the bit is equal to "1", the UART will
be enabled and the TX and RX pins will function as defined by the TXEN and RXEN
enable control bits. When the UART is disabled, it will empty the buffer so any
character remaining in the buffer will be discarded. In addition, the value of the baud
rate counter will be reset. If the UART is disabled, all error and status flags will be
reset. Also the TXEN, RXEN, TXBRK, RXIF, OERR, FERR, PERR and NF bits will
be cleared, while the TIDLE, TXIF and RIDLE bits will be set. Other control bits in
UCR1, UCR2 and BRG registers will remain unaffected. If the UART is active and the
UARTEN bit is cleared, all pending transmissions and receptions will be terminated
and the module will be reset as defined above. When the UART is re-enabled, it will
restart in the same configuration.
Bit 6
BNO: Number of data transfer bits selection
0: 8-bit data transfer
1: 9-bit data transfer
This bit is used to select the data length format, which can have a choice of either
8-bit or 9-bit format. When this bit is equal to "1", a 9-bit data length format will be
selected. If the bit is equal to "0", then an 8-bit data length format will be selected. If
9-bit data length format is selected, then bits RX8 and TX8 will be used to store the 9th
bit of the received and transmitted data respectively.
Note: 1. If BNO=1 (9-bit data transfer) and parity function is enabled, the 9th bit of
data is the parity bit which will not be transferred to RX8.
2. If BNO=0 (8-bit data transfer) and parity function is enabled, the 8th bit of
data is the parity bit which will not be transferred to RX7.
Bit 5
PREN: Parity function enable control
0: Parity function is disabled
1: Parity function is enabled
This bit is the parity function enable bit. When this bit is equal to 1, the parity function
will be enabled. If the bit is equal to 0, then the parity function will be disabled.
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Bit 4
PRT: Parity type selection bit
0: Even parity for parity generator
1: Odd parity for parity generator
This bit is the parity type selection bit. When this bit is equal to 1, odd parity type will
be selected. If the bit is equal to 0, then even parity type will be selected.
Bit 3
STOPS: Number of stop bits selection
0: One stop bit format is used
1: Two stop bits format is used
This bit determines if one or two stop bits are to be used. When this bit is equal to "1",
two stop bits format are used. If the bit is equal to "0", then only one stop bit format is
used.
Bit 2
TXBRK: Transmit break character
0: No break character is transmitted
1: Break characters transmit
The TXBRK bit is the Transmit Break Character bit. When this bit is equal to "0",
there are no break characters and the TX pin operates normally. When the bit is
equal to "1", there are transmit break characters and the transmitter will send logic
zeros. When this bit is equal to "1", after the buffered data has been transmitted, the
transmitter output is held low for a minimum of a 13-bit length and until the TXBRK
bit is reset.
Bit 1
RX8: Receive data bit 8 for 9-bit data transfer format (read only)
This bit is only used if 9-bit data transfers are used, in which case this bit location will
store the 9th bit of the received data known as RX8. The BNO bit is used to determine
whether data transfers are in 8-bit or 9-bit format.
Bit 0
TX8: Transmit data bit 8 for 9-bit data transfer format (write only)
This bit is only used if 9-bit data transfers are used, in which case this bit location
will store the 9th bit of the transmitted data known as TX8. The BNO bit is used to
determine whether data transfers are in 8-bit or 9-bit format.
UCR2 Register
The UCR2 register is the second of the UART control registers and serves several purposes. One
of its main functions is to control the basic enable/disable operation if the UART Transmitter and
Receiver as well as enabling the various UART interrupt sources. The register also serves to control
the baud rate speed, receiver wake-up function enable and the address detect function enable.
Further explanation on each of the bits is given below.
Bit
7
6
5
4
3
Name
TXEN
RXEN
BRGH
ADDEN
WAKE
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
0
0
0
0
0
Bit 7
Rev. 1.20
2
1
0
RIE
TIIE
TEIE
R/W
R/W
R/W
0
0
TXEN: UART Transmitter enable control
0: UART Transmitter is disabled
1: UART Transmitter is enabled
The TXEN bit is the Transmitter Enable Bit. When this bit is equal to "0", the
transmitter will be disabled with any pending data transmissions being aborted. In
addition the buffers will be reset. In this situation the TX pin will be used as an I/O or
other pin-shared functional pin. If the TXEN bit is equal to "1" and the UARTEN bit is
also equal to 1, the transmitter will be enabled and the TX pin will be controlled by the
UART. Clearing the TXEN bit during a transmission will cause the data transmission
to be aborted and will reset the transmitter.
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Rev. 1.20
Bit 6
RXEN: UART Receiver enable control
0: UART Receiver is disabled
1: UART Receiver is enabled
The RXEN bit is the Receiver Enable Bit. When this bit is equal to "0", the receiver
will be disabled with any pending data receptions being aborted. In addition the
receiver buffers will be reset. In this situation the RX pin will be used as an I/O or
other pin-shared functional pin. If the RXEN bit is equal to "1" and the UARTEN bit
is also equal to 1, the receiver will be enabled and the RX pin will be controlled by the
UART. Clearing the RXEN bit during a reception will cause the data reception to be
aborted and will reset the receiver.
Bit 5
BRGH: Baud Rate speed selection
0: Low speed baud rate
1: High speed baud rate
The bit named BRGH selects the high or low speed mode of the Baud Rate Generator.
This bit, together with the value placed in the baud rate register, BRG, controls the
baud rate of the UART. If the bit is equal to 0, the low speed mode is selected.
Bit 4
ADDEN: Address detect function enable control
0: Address detection function is disabled
1: Address detection function is enabled
The bit named ADDEN is the address detection function enable control bit. When this
bit is equal to 1, the address detection function is enabled. When it occurs, if the 8th
bit, which corresponds to RX7 if BNO=0, or the 9th bit, which corresponds to RX8 if
BNO=1, has a value of "1", then the received word will be identified as an address,
rather than data. If the corresponding interrupt is enabled, an interrupt request will be
generated each time the received word has the address bit set, which is the 8th or 9th
bit depending on the value of the BNO bit. If the address bit known as the 8th or 9th
bit of the received word is "0" with the address detection function being enabled, an
interrupt will not be generated and the received data will be discarded.
Bit 3
WAKE: RX pin falling edge wake-up function enable control
0: RX pin wake-up UART function is disabled
1: RX pin wake-up UART function is enabled
The bit is used to control the wake-up UART function when a falling edge on the RX
pin occurs. Note that this bit is only available when the UART clock, fSYS, is switched
off. There will be no RX pin wake-up UART function if the UART clock, fSYS, exists.
If the WAKE bit is equal to 1 and the UART clock, fSYS, is switched off, a UART
wake-up request will be initiated when a falling edge on the RX pin occurs. When
this request happens and the corresponding interrupt is enabled, an RX pin wake-up
UART interrupt will be generated to inform the MCU to wake up the UART function
by switching on the UART clock, fSYS, via the application programs. Otherwise, the
UART function can not resume even if there is a falling edge on the RX pin when the
WAKE bit is cleared to 0.
Bit 2
RIE: Receiver interrupt enable control
0: Receiver related interrupt is disabled
1: Receiver related interrupt is enabled
The bit enables or disables the receiver interrupt. If this bit is equal to 1 and when the
receiver overrun flag OERR or received data available flag RXIF is set, the UART
interrupt request flag will be set. If this bit is equal to 0, the UART interrupt request
flag will not be influenced by the condition of the OERR or RXIF flags.
Bit 1
TIIE: Transmitter Idle interrupt enable control
0: Transmitter idle interrupt is disabled
1: Transmitter idle interrupt is enabled
The bit enables or disables the transmitter idle interrupt. If this bit is equal to 1 and
when the transmitter idle flag TIDLE is set, due to a transmitter idle condition, the
UART interrupt request flag will be set. If this bit is equal to 0, the UART interrupt
request flag will not be influenced by the condition of the TIDLE flag.
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Bit 0
TEIE: Transmitter Empty interrupt enable control
0: Transmitter empty interrupt is disabled
1: Transmitter empty interrupt is enabled
The bit enables or disables the transmitter empty interrupt. If this bit is equal to 1 and
when the transmitter empty flag TXIF is set, due to a transmitter empty condition, the
UART interrupt request flag will be set. If this bit is equal to 0, the UART interrupt
request flag will not be influenced by the condition of the TXIF flag.
TXR_RXR Register
The TXR_RXR register is the data register which is used to store the data to be transmitted on the
TX pin or being received from the RX pin.
Bit
7
6
5
4
3
2
1
0
Name
TXRX7
TXRX6
TXRX5
TXRX4
TXRX3
TXRX2
TXRX1
TXRX0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
×
×
×
×
×
×
×
×
"×": unknown
Bit 7~0
TXRX7~TXRX0: UART Transmit/Receive Data bits
Baud Rate Generator
To setup the speed of the serial data communication, the UART function contains its own dedicated
baud rate generator. The baud rate is controlled by its own internal free running 8-bit timer, the
period of which is determined by two factors. The first of these is the value placed in the BRG
register and the second is the value of the BRGH bit within the UCR2 control register. The BRGH
bit decides, if the baud rate generator is to be used in a high speed mode or low speed mode, which
in turn determines the formula that is used to calculate the baud rate. The value in the BRG register,
N, which is used in the following baud rate calculation formula determines the division factor. Note
that N is the decimal value placed in the BRG register and has a range of between 0 and 255.
UCR2 BRGH Bit
0
1
Baud Rate (BR)
fSYS / [64 (N+1)]
fSYS / [16 (N+1)]
By programming the BRGH bit which allows selection of the related formula and programming the
required value in the BRG register, the required baud rate can be setup. Note that because the actual
baud rate is determined using a discrete value, N, placed in the BRG register, there will be an error
associated between the actual and requested value. The following example shows how the BRG
register value N and the error value can be calculated.
BRG Register
Bit
7
6
5
4
3
2
1
0
Name
BRG7
BRG6
BRG5
BRG4
BRG3
BRG2
BRG1
BRG0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
×
×
×
×
×
×
×
×
"×": unknown
Bit 7~0
BRG7~BRG0: Baud Rate values
By programming the BRGH bit in the UCR2 register which allows selection of the
related formula described above and programming the required value in the BRG
register, the required baud rate can be setup.
Rev. 1.20
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Calculating the Baud Rate and Error Values
For a clock frequency of 4MHz, and with BRGH set to 0 determine the BRG register value N, the
actual baud rate and the error value for a desired baud rate of 4800.
From the above table the desired baud rate BR=fSYS / [64 (N+1)]
Re-arranging this equation gives N=[fSYS / (BR×64)] - 1
Giving a value for N=[4000000 / (4800×64)] - 1=12.0208
To obtain the closest value, a decimal value of 12 should be placed into the BRG register. This gives
an actual or calculated baud rate value of BR=4000000 / [64×(12+1)]=4808
Therefore the error is equal to (4808 - 4800) / 4800=0.16%
UART Setup and Control
For data transfer, the UART function utilizes a non-return-to-zero, more commonly known as NRZ,
format. This is composed of one start bit, eight or nine data bits and one or two stop bits. Parity
is supported by the UART hardware and can be setup to be even, odd or no parity. For the most
common data format, 8 data bits along with no parity and one stop bit, denoted as 8, N, 1, is used
as the default setting, which is the setting at power-on. The number of data bits and stop bits, along
with the parity, are setup by programming the corresponding BNO, PRT, PREN and STOPS bits in
the UCR1 register. The baud rate used to transmit and receive data is setup using the internal 8-bit
baud rate generator, while the data is transmitted and received LSB first. Although the transmitter
and receiver of the UART are functionally independent, they both use the same data format and baud
rate. In all cases stop bits will be used for data transmission.
Enabling/Disabling the UART Interface
The basic on/off function of the internal UART function is controlled using the UARTEN bit in the
UCR1 register. If the UARTEN, TXEN and RXEN bits are set, then these two UART pins will act
as normal TX output pin and RX input pin respectively. If no data is being transmitted on the TX
pin, then it will default to a logic high value.
Clearing the UARTEN bit will disable the TX and RX pins and then these two pins can be used as
an I/O or other pin-shared functional pins by properly configurations. When the UART function is
disabled, the buffer will be reset to an empty condition, at the same time discarding any remaining
residual data. Disabling the UART will also reset the enable control, the error and status flags with
bits TXEN, RXEN, TXBRK, RXIF, OERR, FERR, PERR and NF being cleared while bits TIDLE,
TXIF and RIDLE will be set. The remaining control bits in the UCR1, UCR2 and BRG registers will
remain unaffected. If the UARTEN bit in the UCR1 register is cleared while the UART is active,
then all pending transmissions and receptions will be immediately suspended and the UART will
be reset to a condition as defined above. If the UART is then subsequently re-enabled, it will restart
again in the same configuration.
Rev. 1.20
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Data, Parity and Stop Bit Selection
The format of the data to be transferred is composed of various factors such as data bit length, parity
on/off, parity type, address bits and the number of stop bits. These factors are determined by the setup
of various bits within the UCR1 register. The BNO bit controls the number of data bits which can
be set to either 8 or 9. The PRT bit controls the choice if odd or even parity. The PREN bit controls
the parity on/off function. The STOPS bit decides whether one or two stop bits are to be used. The
following table shows various formats for data transmission. The address bit, which is the MSB of the
data byte, identifies the frame as an address character or data if the address detect function is enabled.
The number of stop bits, which can be either one or two, is independent of the data length.
Start Bit
Data Bits
Address Bits
Parity Bit
Stop Bit
Example of 8-bit Data Formats
1
8
0
0
1
1
7
0
1
1
1
7
1
0
1
Example of 9-bit Data Formats
1
9
0
0
1
1
8
0
1
1
1
8
1
0
1
Transmitter Receiver Data Format
The following diagram shows the transmit and receive waveforms for both 8-bit and 9-bit data formats.
Sta�t
Bit
Pa�ity Bit
Bit 0
Bit 1
Bit 2
Bit 3
Bit 4
Bit �
Bit �
Bit 7
8-bit Data Format
Sta�t
Bit
Bit 0
Bit 1
Bit 2
Bit 3
Bit 4
Bit �
Stop
Bit
Next
Sta�t
Bit
Pa�ity Bit
Bit �
Bit 7
Bit 8
Stop
Bit
Next
Sta�t
Bit
9-bit Data Format
UART Transmitter
Data word lengths of either 8 or 9 bits can be selected by programming the BNO bit in the UCR1
register. When BNO bit is set, the word length will be set to 9 bits. In this case the 9th bit, which
is the MSB, needs to be stored in the TX8 bit in the UCR1 register. At the transmitter core lies
the Transmitter Shift Register, more commonly known as the TSR, whose data is obtained from
the transmit data register, which is known as the TXR_RXR register. The data to be transmitted
is loaded into this TXR_RXR register by the application program. The TSR register is not written
to with new data until the stop bit from the previous transmission has been sent out. As soon as
this stop bit has been transmitted, the TSR can then be loaded with new data from the TXR_RXR
register, if it is available. It should be noted that the TSR register, unlike many other registers, is not
directly mapped into the Data Memory area and as such is not available to the application program
for direct read/write operations. An actual transmission of data will normally be enabled when the
TXENn bit is set, but the data will not be transmitted until the TXR_RXR register has been loaded
with data and the baud rate generator has defined a shift clock source. However, the transmission
can also be initiated by first loading data into the TXR_RXR register, after which the TXEN bit can
be set. When a transmission of data begins, the TSR is normally empty, in which case a transfer to
the TXR_RXR register will result in an immediate transfer to the TSR. If during a transmission the
TXEN bit is cleared, the transmission will immediately cease and the transmitter will be reset. The
TX output pin can then return to the I/O or other pin-shared function by properly configurations.
Rev. 1.20
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Transmitting Data
When the UART is transmitting data, the data is shifted on the TX pin from the shift register, with
the least significant bit LSB first. In the transmit mode, the TXR_RXR register forms a buffer
between the internal bus and the transmitter shift register. It should be noted that if 9-bit data format
has been selected, then the MSB will be taken from the TX8 bit in the UCR1 register. The steps to
initiate a data transfer can be summarized as follows:
• Make the correct selection of the BNO, PRT, PREN and STOPS bits to define the required word
length, parity type and number of stop bits.
• Setup the BRG register to select the desired baud rate.
• Set the TXEN bit to ensure that the UART transmitter is enabled and the TX pin is used as a
UART transmitter pin.
• Access the USR register and write the data that is to be transmitted into the TXR_RXR register.
Note that this step will clear the TXIF bit.
This sequence of events can now be repeated to send additional data. It should be noted that when
TXIF=0, data will be inhibited from being written to the TXR_RXR register. Clearing the TXIF flag
is always achieved using the following software sequence:
1. A USR register access
2. A TXR_RXR register write execution
The read-only TXIF flag is set by the UART hardware and if set indicates that the TXR_RXR
register is empty and that other data can now be written into the TXR_RXR register without
overwriting the previous data. If the TEIE bit is set, then the TXIF flag will generate an interrupt.
During a data transmission, a write instruction to the TXR_RXR register will place the data into the
TXR_RXR register, which will be copied to the shift register at the end of the present transmission.
When there is no data transmission in progress, a write instruction to the TXR_RXR register will
place the data directly into the shift register, resulting in the commencement of data transmission,
and the TXIF bit being immediately set. When a frame transmission is complete, which happens
after stop bits are sent or after the break frame, the TIDLE bit will be set. To clear the TIDLEn bit
the following software sequence is used:
1. A USR register access
2. A TXR_RXR register write execution
Note that both the TXIF and TIDLE bits are cleared by the same software sequence.
Transmitting Break
If the TXBRK bit is set, then the break characters will be sent on the next transmission. Break
character transmission consists of a start bit, followed by 13xN "0" bits, where N=1, 2, etc. If a
break character is to be transmitted, then the TXBRK bit must be first set by the application program
and then cleared to generate the stop bits. Transmitting a break character will not generate a transmit
interrupt. Note that a break condition length is at least 13 bits long. If the TXBRK bit is continually
kept at a logic high level, then the transmitter circuitry will transmit continuous break characters.
After the application program has cleared the TXBRK bit, the transmitter will finish transmitting the
last break character and subsequently send out one or two stop bits. The automatic logic high at the
end of the last break character will ensure that the start bit of the next frame is recognized.
Rev. 1.20
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UART Receiver
The UART is capable of receiving word lengths of either 8 or 9 bits can be selected by programming
the BNO bit in the UCR1 register. When BNO bit is set, the word length will be set to 9 bits. In
this case the 9th bit, which is the MSB, will be stored in the RX8 bit in the UCR1 register. At the
receiver core lies the Receiver Shift Register more commonly known as the RSR. The data which
is received on the RX external input pin is sent to the data recovery block. The data recovery block
operating speed is 16 times that of the baud rate, while the main receive serial shifter operates at the
baud rate. After the RX pin is sampled for the stop bit, the received data in RSR is transferred to the
receive data register, if the register is empty. The data which is received on the external RX input pin
is sampled three times by a majority detect circuit to determine the logic level that has been placed
onto the RX pin. It should be noted that the RSR register, unlike many other registers, is not directly
mapped into the Data Memory area and as such is not available to the application program for direct
read/write operations.
Receiving Data
When the UART receiver is receiving data, the data is serially shifted in on the external RX input
pin to the shift register, with the least significant bit LSB first. The TXR_RXR register is a two byte
deep FIFO data buffer, where two bytes can be held in the FIFO while the 3rd byte can continue to be
received. Note that the application program must ensure that the data is read from TXR_RXR before
the 3rd byte has been completely shifted in, otherwise the 3rd byte will be discarded and an overrun
error OERR will be subsequently indicated. The steps to initiate a data transfer can be summarized
as follows:
• Make the correct selection of the BNO, PRT, PREN and STOPS bits to define the required word
length, parity type and number of stop bits.
• Setup the BRG register to select the desired baud rate.
• Set the RXEN bit to ensure that the UART receiver is enabled and the RX pin is used as a UART
receiver pin.
At this point the receiver will be enabled which will begin to look for a start bit.
When a character is received, the following sequence of events will occur:
• The RXIF bit in the USR register will be set when the TXR_RXR register has data available.
There will be at most one more character that can be read.
• When the contents of the shift register have been transferred to the TXR_RXR register and if the
RIE bit is set, then an interrupt will be generated.
• If during reception, a frame error, noise error, parity error or an overrun error has been detected,
then the error flags can be set.
The RXIF bit can be cleared using the following software sequence:
1. A USR register access
2. A TXR_RXR register read execution
Rev. 1.20
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Receiving Break
Any break character received by the UART will be managed as a framing error. The receiver will
count and expect a certain number of bit times as specified by the values programmed into the BNO
and STOPS bits. If the break is much longer than 13 bit times, the reception will be considered as
complete after the number of bit times specified by BNO and STOPS. The RXIF bit is set, FERR
is set, zeros are loaded into the receive data register, interrupts are generated if appropriate and
the RIDLE bit is set. A break is regarded as a character that contains only zeros with the FERR
flag being set. If a long break signal has been detected, the receiver will regard it as a data frame
including a start bit, data bits and the invalid stop bit and the FERR flag will be set. The receiver
must wait for a valid stop bit before looking for the next start bit. The receiver will not make the
assumption that the break condition on the line is the next start bit. The break character will be
loaded into the buffer and no further data will be received until stop bits are received. It should be
noted that the RIDLE read only flag will go high when the stop bits have not yet been received. The
reception of a break character on the UART registers will result in the following:
• The framing error flag, FERR, will be set.
• The receive data register, TXR_RXR, will be cleared.
• The OERR, NF, PERR, RIDLE or RXIF flags will possibly be set.
Idle Status
When the receiver is reading data, which means it will be in between the detection of a start bit and
the reading of a stop bit, the receiver status flag in the USR register, otherwise known as the RIDLE
flag, will have a zero value. In between the reception of a stop bit and the detection of the next start
bit, the RIDLE flag will have a high value, which indicates the receiver is in an idle condition.
Receiver Interrupt
The read only receive interrupt flag, RXIF, in the USR register is set by an edge generated by the
receiver. An interrupt is generated if RIE=1, when a word is transferred from the Receive Shift
Register, RSR, to the Receive Data Register, TXR_RXR. An overrun error can also generate an
interrupt if RIE=1.
Managing Receiver Errors
Several types of reception errors can occur within the UART module, the following section describes
the various types and how they are managed by the UART.
Overrun Error – OERR
The TXR_RXR register is composed of a two byte deep FIFO data buffer, where two bytes can
be held in the FIFO register, while a 3th byte can continue to be received. Before the 3th byte has
been entirely shifted in, the data should be read from the TXR_RXR register. If this is not done, the
overrun error flag OERR will be consequently indicated.
In the event of an overrun error occurring, the following will happen:
• The OERR flag in the USR register will be set.
• The TXR_RXR contents will not be lost.
• The shift register will be overwritten.
• An interrupt will be generated if the RIE bit is set.
The OERR flag can be cleared by an access to the USR register followed by a read to the TXR_
RXR register.
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Noise Error – NF
Over-sampling is used for data recovery to identify valid incoming data and noise. If noise is
detected within a frame, the following will occur:
• The read only noise flag, NF, in the USR register will be set on the rising edge of the RXIF bit.
• Data will be transferred from the shift register to the TXR_RXR register.
• No interrupt will be generated. However this bit rises at the same time as the RXIF bit which
itself generates an interrupt.
Note that the NF flag is reset by an USR register read operation followed by a TXR_RXR register
read operation.
Framing Error – FERR
The read only framing error flag, FERR, in the USR register, is set if a zero is detected instead of
stop bits. If two stop bits are selected, both stop bits must be high. Otherwise the FERR flag will
be set. The FERR flag and the received data will be recorded in the USR and TXR_RXR registers
respectively and the FERR flag will be cleared in any reset.
Parity Error – PERR
The read only parity error flag, PERR, in the USR register, is set if the parity of the received word
is incorrect. This error flag is only applicable if the parity function is enabled, PREN=1, and if the
parity type, odd or even, is selected. The read only PERR flag and the received data will be recorded
in the USR and TXR_RXR registers respectively and the flag will be cleared on any reset. It should
be noted that the FERR and PERR flags in the USR register should first be read by the application
programs before reading the data word.
UART Interrupt Structure
Several individual UART conditions can generate a UART interrupt. When these conditions exist,
a low pulse will be generated to get the attention of the microcontroller. These conditions are a
transmitter data register empty, transmitter idle, receiver data available, receiver overrun, address
detect and an RX pin wake-up. When any of these conditions are created, if its corresponding
interrupt control is enabled and the stack is not full, the program will jump to its corresponding
interrupt vector where it can be serviced before returning to the main program. Four of these
conditions have the corresponding USR register flags which will generate a UART interrupt if its
associated interrupt enable control bit in the UCR2 register is set. The two transmitter interrupt
conditions have their own corresponding enable control bits, while the two receiver interrupt
conditions have a shared enable control bit. These enable bits can be used to mask out individual
UART interrupt sources.
The address detect condition, which is also a UART interrupt source, does not have an associated
flag, but will generate a UART interrupt when an address detect condition occurs if its function
is enabled by setting the ADDEN bit in the UCR2 register. An RX pin wake-up, which is also a
UART interrupt source, does not have an associated flag, but will generate a UART interrupt if the
microcontroller is woken up from the IDLE0 or SLEEP mode by a falling edge on the RX pin if the
WAKE and RIE bits in the UCR2 register are set. Note that in the event of an RX wake-up interrupt
occurring, there will be a certain period of delay, commonly known as the System Start-up Time, for
the oscillator to restart and stabilize before the system resumes normal operation.
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Note that the USR register flags are read only and cannot be cleared or set by the application
program, neither will they be cleared when the program jumps to the corresponding interrupt
servicing routine, as is the case for some of the other interrupts. The flags will be cleared
automatically when certain actions are taken by the UART, the details of which are given in the
UART register section. The overall UART interrupt can be disabled or enabled by the related
interrupt enable control bits in the interrupt control registers of the microcontroller to decide whether
the interrupt requested by the UART module is masked out or allowed.
UCR2 Register
USR Register
Transmitter Empty Flag
TXIF
TEIE
Transmitter Idle Flag
TIDLE
TIIE
1
RIE
OR
ADDEN
Receiver Data Available
RXIF
WAKE
0
1
Receiver Overrun Flag
OERR
RX Pin
Wake-up
0
URE
0
EMI
1
0
1
Interrupt signal
to MCU
1
0
1
0
0
UART Interrupt
Request Flag
URF
0
1
TXR_RXR.7 if BNO=0
RX8 if BNO=1
1
UCR2 Register
UART Interrupt Structure
Address Detect Mode
Setting the Address Detect function enable control bit, ADDEN, in the UCR2 register, enables this
special function. If this bit is set to 1, then an additional qualifier will be placed on the generation
of a Receiver Data Available interrupt, which is requested by the RXIF flag. If the ADDEN bit
is equal to 1, then when the data is available, an interrupt will only be generated, if the highest
received bit has a high value. Note that the related interrupt enable control bit and the EMI bit of the
microcontroller must also be enabled for correct interrupt generation. The highest address bit is the
9th bit if the bit BNO=1 or the 8th bit if the bit BNO=0. If the highest bit is high, then the received
word will be defined as an address rather than data. A Data Available interrupt will be generated
every time the last bit of the received word is set. If the ADDEN bit is equal to 0, then a Receive
Data Available interrupt will be generated each time the RXIF flag is set, irrespective of the data last
bit status. The address detection and parity functions are mutually exclusive functions. Therefore, if
the address detect function is enabled, then to ensure correct operation, the parity function should be
disabled by resetting the parity function enable bit PREN to zero.
ADDEN
Bit 9 if BNO=1
Bit 8 if BNO=0
UART Interrupt
Generated
0
√
0
1
1
√
0
×
1
√
ADDEN Bit Function
Rev. 1.20
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Touch A/D Flash MCU with OCVP
UART Power Down and Wake-up
When the system clock, fSYS, is switched off, the UART will cease to function. If the MCU executes
the "HALT" instruction which results in the system clock being switched off while a transmission is
still in progress, then the transmission will be paused until the UART clock source derived from the
microcontroller is activated. In a similar way, if the MCU executes the "HALT" instructure which
results in the system clock being switched off while receiving data, then the reception of data will
likewise be paused. When the MCU enters the power down mode, note that the USR, UCR1, UCR2,
transmit and receive registers, as well as the BRG register will not be affected. It is recommended
to make sure first that the UART data transmission or reception has been finished before the
microcontroller enters the power down mode.
The UART function contains a receiver RX pin wake-up function, which is enabled or disabled
by the WAKE bit in the UCR2 register. If this bit, along with the UART enable bit, UARTEN, the
receiver enable bit, RXEN and the receiver interrupt bit, RIE, are all set before the MCU enters the
power down mode with the UART clock fSYS being switched off, then a falling edge on the RX pin
will initiate a RX pin wake-up UART interrupt. Note that as it takes certain system clock cycles after
a wake-up, before normal microcontroller operation resumes, any data received during this time on
the RX pin will be ignored.
For a UART wake-up interrupt to occur, in addition to the bits for the wake-up being set, the global
interrupt enable bit, EMI, and the UART interrupt enable bit, URE, must be set. If the EMI and URE
bits are not set then only a wake up event will occur and no interrupt will be generated. Note also
that as it takes certain system clock cycles after a wake-up before normal microcontroller resumes,
the UART interrupt will not be generated until after this time has elapsed.
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Over Current/Voltage Protection Function – OCVP
The series of devices includes a current/voltage protection function which provides a protection
mechanism for applications, for example, over current or over voltage protection, etc. The current on
the OCVPAI0, OCVPAI1 and OCVPAI2 pins are 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.
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, OCVPAI1 or OCVPAI2 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
compared with a reference provided by the 8-bit D/A converter.
VDD OCVPVR
OCVPVRS
OCVPDA[7:0]
8-bit
D/A
OCVPEN
S0
OCVPAI0
OCVPAI1
OCVPCOUT
OCVPEN
S2
fDEB=fSYS
S3
S4
S5
CMP
OCVPCI
OCVPCHY
OCVPAI2
S7
OCVPINT
OCVPSPOL
6.6KΩ or 13.2KΩ
OCVPG2XEN
Debounce
OPA
R1
OCVPCPS
S6
OCVPO
OCVPEN
S1
R2
OCVPDEB[2:0]
OCVPCOUT
OCVPAO
To A/D internal input
OCVPSWn
(n=0~6)
OCVPSW7
OCVPG[2:0]
Gain=1/4/6/10/15/25/40/65
OCVP Block Diagram
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 OCVPVR, 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.
If the 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, as shown in the following diagram, so the OCVPSPOL bit must be properly configured
according to user’s application requirements.
Rev. 1.20
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Note that the debounce clock, fDEB, comes from the system clock, fSYS. The operational amplifier
output voltage also can be read out by the A/D converter through an A/D internal input channel. 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. One register is used to
provide the reference voltages for the OCVP circuit. There are two registers used to cancel out the
operational amplifier and comparator input offset. The remaining four 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. Each OCVP related input or output
signal has a corresponding control bit in the OCVPC3 register. 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
OCVPC0
OCVPSW7
OCVPSW6
OCVPSW5
OCVPSW4
OCVPSW3
OCVPSW2
OCVPSW1
OCVPSW0
OCVPCPS
OCVPVRS
OCVPC1
OCVPEN
OCVPCHY
OCVPO
OCVPSPOL
—
—
OCVPC2
—
OCVPG2XEN
OCVPG2
OCVPG1
OCVPG0
OCVPDEB2
OCVPDEB1 OCVPDEB0
OCVPC3
OCVPCIEN
OCVPAI2EN
—
—
OCVPOPEN OCVPCPEN
OCVPDA
D7
D6
D3
D2
OCVPAI1EN OCVPAI0EN
D5
D4
D1
D0
OCVPOCAL OCVPOOFM
OCVPORSP
OCVPOOF5 OCVPOOF4 OCVPOOF3 OCVPOOF2 OCVPOOF1 OCVPOOF0
OCVPCCAL OCVPCOUT
OCVPCOFM
OCVPCRSP OCVPCOF4
OCVPCOF3
OCVPCOF2 OCVPCOF1 OCVPCOF0
OCVP Registers List
OCVPC0 Register
Bit
Name
Rev. 1.20
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
R/W
R/W
R/W
R/W
POR
1
1
0
0
1
0
0
0
Bit 7
OCVPSW7: OCVP switch S7 on/off control
0: Off
1: On
Bit 6
OCVPSW6: OCVP switch S6 on/off control
0: Off
1: On
Bit 5
OCVPSW5: OCVP switch S5 on/off control
0: Off
1: On
Bit 4
OCVPSW4: OCVP switch S4 on/off control
0: Off
1: On
Bit 3
OCVPSW3: OCVP switch S3 on/off control
0: Off
1: On
Bit 2
OCVPSW2: OCVP switch S2 on/off control
0: Off
1: On
165
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Bit 1
OCVPSW1: OCVP switch S1 on/off control
0: Off
1: On
Bit 0
OCVPSW0: OCVP switch S0 on/off control
0: Off
1: On
OCVPC1 Register
Bit
7
Name
6
5
OCVPEN OCVPCHY
4
OCVPO OCVPSPOL
3
2
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 7
OCVPEN: 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 6
OCVPCHY: OCVP Comparator Hysteresis function enable control
0: Disable
1: Enable
Bit 5
OCVPO: OCVP Comparator debounced output
This bit is the debounced version of the OCVPCOUT bit
Bit 4
OCVPSPOL: OCVPO polarity control
0: Not inverted
1: Inverted
Bit 3~2
Unimplemented, read as "0"
Bit 1
OCVPCPS: OCVP Comparator non-inverting input selection
0: From OCVPAO – OPA output
1: From OCVPCI pin
Bit 0
OCVPVRS: OCVP D/A converter reference voltage selection
0: From VDD pin
1: From OCVPVR pin
OCVPC2 Register
Rev. 1.20
Bit
7
Name
—
6
5
4
3
2
1
0
R/W
—
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
—
0
0
0
0
0
0
0
OCVPG2XEN OCVPG2 OCVPG1 OCVPG0 OCVPDEB2 OCVPDEB1 OCVPDEB0
Bit 7
Unimplemented, read as "0"
Bit 6
OCVPG2XEN: OCVP PGA R2/R1 ratio doubling enable control
0: Disable (R1=13.2kΩ)
1: Enable (R1=6.6kΩ)
When this bit is set to 1, the R2/R1 ratio selected by the OCVPG2~OCVPG0 bits will
be doubled.
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Bit 5~3
OCVPG2~OCVPG0: OCVP 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 2~0
OCVPDEB2~OCVPDEB0: OCVP Comparator output debounce time selection
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: tDEB=1/fDEB, fDEB=fSYS
OCVPC3 Register
Bit
7
6
5
4
Name OCVPCIEN OCVPAI2EN OCVPAI1EN OCVPAI0EN
Rev. 1.20
3
2
—
—
1
0
OCVPOPEN OCVPCPEN
R/W
R/W
R/W
R/W
R/W
—
—
R/W
R/W
POR
0
0
0
0
—
—
0
0
Bit 7
OCVPCIEN: OCVPCI input signal control
0: Disable
1: Enable
When the OCVPEN bit is set to 0 to disable the OCVP, the OCVPCI input will be
forced to disable.
Bit 6
OCVPAI2EN: OCVPAI2 input signal control
0: Disable
1: Enable
When the OCVPEN bit is set to 0 to disable the OCVP, the OCVPAI2 input will be
forced to disable.
Bit 5
OCVPAI1EN: OCVPAI1 input signal control
0: Disable
1: Enable
When the OCVPEN bit is set to 0 to disable the OCVP, the OCVPAI1 input will be
forced to disable.
Bit 4
OCVPAI0EN: OCVPAI0 input signal control
0: Disable
1: Enable
When the OCVPEN bit is set to 0 to disable the OCVP, the OCVPAI0 input will be
forced to disable.
Bit 3~2
Unimplemented, read as "0"
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Bit 1
OCVPOPEN: OCVPAO output signal control
0: Disable
1: Enable
When the OCVPEN bit is set to 0 to disable the OCVP, the OCVP OPA output will be
forced to disable.
Bit 0
OCVPCPEN: OCVPCOUT output signal control
0: Disable
1: Enable
When the OCVPEN bit is set to 0 to disable the OCVP, the OCVP comparator output
will be forced to disable.
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
1
0
Bit 7~0
OCVP D/A Converter Data register bit 7 ~ bit 0
OCVP D/A Converter Output=(DAC reference voltage/256)×D[7:0]
OCVPOCAL Register
Bit
7
6
5
4
3
2
Name OCVPOOFM OCVPORSP OCVPOOF5 OCVPOOF4 OCVPOOF3 OCVPOOF2 OCVPOOF1 OCVPOOF0
Rev. 1.20
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 7
OCVPOOFM: OCVP Operational Amplifier operating mode selection
0: Normal operating mode
1: Offset cancellation mode
This bit is used to select the OCVP Operational Amplifier operating mode. To select
the Operational Amplifier input offset cancellation mode, the OCVPSW bit field 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 6
OCVPORSP: OCVP Operational Amplifier input offset cancellation reference input selection
0: Operational Amplifier inverting input
1: Operational Amplifier non-inverting input
Bit 5~0
OCVPOOF5~OCVPOOF0: OCVP Operational Amplifier input offset cancellation value
This 6-bit field is used to perform the Operational Amplifier input offset cancellation
operation and the value after the input offset cancellation can be restored into this
field. More detailed information is described in the "Operational Amplifier Input
Offset Cancellation" section.
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OCVPCCAL Register
Bit
Name
7
6
5
4
3
2
1
0
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-inverting input voltage < D/A converter output voltage
1: Non-inverting input voltage > D/A converter output voltage
This bit is used to indicate whether the non-onverting input voltage is greater than the
D/A converter output voltage. If the OCVPCOUT bit is set to 1, it means that the nononverting input voltage is greater than the D/A converter output voltage. Otherwise,
the non-inverting input voltage is less than the D/A converter output voltage. This bit
value can be output on the OCVPCOUT pin.
Bit 6
OCVPCOFM: 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 OCVPSW bit field 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 5
OCVPCRSP: OCVP Comparator input offset cancellation reference input selection
0: Comparator inverting input
1: Comparator non-inverting input
Bit 4~0
OCVPCOF4~OCVPCOF0: OCVP Comparator input offset cancellation value
This 5-bit field is used to perform the comparator input offset cancellation operation
and the value after the input offset cancellation can be restored into this field. Refer to
the "Comparator Input Offset Cancellation" section for more detailed information.
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 the
OCVPSW6~OCVPSW4 bits are set to "000", the PGA gain will be equal to 1 and the PGA will
act as a unity gain buffer. The switches, S6, S5 and S4, will be switched off internally and the
PGA output voltage is equal to VIN.
VOUT  VIN
• If S3 and S4 are switched on, the input node is OCVPAI0. For 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  
Rev. 1.20
169
R2
x V IN
R1
December 05, 2016
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Touch A/D Flash MCU with OCVP
Input Offset Cancellation
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
Setp 1. Set OCVPSW [7:0]=28H (S3 and S5 are ON, other switches are OFF).
Set OCVPOOFM=1, OCVPCOFM=0, OCVPORSP=1, OCVPCPS=0
Now the OCVP is operating in the Operational Amplifier input offset cancellation mode.
Setp 2. Set OCVPDA [7:0]=40H
Setp 3. Set OCVPOOF [5:0]=000000 and read the OCVPCOUT bit
Setp 4. Increase the OCVPOOF [5:0] value by 1 and then read the OCVPCOUT bit.
If the OCVPCOUT bit state is not changed, then repeat Step 4 until the OCVPCOUT bit
state is changed.
If the OCVPCOUT bit state is changed, then record the current OCVPOOF field value as
VOOS1 and then go to Step 5.
Setp 5. Set OCVPOOF [5:0]=111111 and read the OCVPCOUT bit
Setp 6. Decrease the OCVPOOF [5:0] value by 1 and then read the OCVPCOUT bit.
If the OCVPCOUT bit state is not changed, then repeat Step 6 until the OCVPCOUT bit
state is changed.
If the OCVPCOUT bit state is changed, then record the current OCVPOOF field value as
VOOS2 and then go to Step 7.
Setp 7. Restore the operational amplifier input offset cancellation value VOOS into the OCVPOOF
[5:0] bit field. The offset cancellation procedure is now finished with the VOOS value as the
following formula shown.
VOOS 
Rev. 1.20
170
VOOS1  VOOS2
2
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
Comparator Input Offset Cancellation
Before the offset cancellationexecuted, the hysteresis voltage shoule be zero by setting the
OCVPCHY bit to 0.
Setp 1. Set OCVPSW [7:0]=28H (S3 and S5 are ON, other switches are OFF).
Set OCVPCOFM=1, OCVPOOFM=0, OCVPCRSP=0
Now the OCVP is operating in the Comparator input offset cancellation mode.
Setp 2. Set OCVPDA [7:0]=40H
Setp 3. Set OCVPCOF [4:0]=00000 and read the OCVPCOUT bit
Setp 4. Increase the OCVPCOF [4:0] value by 1 and then read the OCVPCOUT bit.
If the OCVPCOUT bit state is not changed, then repeat Step 4 until the OCVPCOUT bit
state is changed.
If the OCVPCOUT bit state is changed, then record the current OCVPCOF field value as
VCOS1 and then go to Step 5.
Setp 5. Set OCVPCOF [4:0]=11111 and read the OCVPCOUT bit
Setp 6. Decrease the OCVPCOF [4:0] value by 1 and then read the OCVPCOUT bit.
If the OCVPCOUT bit state is not changed, then repeat Step 6 until the OCVPCOUT bit
state is changed.
If the OCVPCOUT bit state is changed, then record the current OCVPCOF field value as
VCOS2 and then go to Step 7.
Setp 7. Restore the comparator input offset cancellation value VCOS into the OCVPCOF [4:0]
bit field. The offset cancellation procedure is now finished with the VCOS value as the
following formula shown.
VCOS 
VCOS1  VCOS2
2
OCVP Interrupt
The OCVP possesses its own interrupt function. When the OCVP comparator debounced output
changes state, its relevant interrupt flag will be set, and if the corresponding interrupt enable bit
is set, then a jump to its relevant interrupt vector will be executed. If the microcontroller is in the
SLEEP or IDLE Mode and the OCVP function is enabled, then if the external input lines cause the
OCVP Comparator debounced output to change state, the resulting generated interrupt flag will also
generate a wake-up. If it is required to disable a wake-up from occurring, then the interrupt flag
should be first set high before entering the SLEEP or IDLE Mode.
Programming Considerations
If the OCVP is enabled, it will remain active when the microcontroller enters the SLEEP or IDLE
Mode, however as it will consume a certain amount of power, the user may wish to consider
disabling it before the SLEEP or IDLE Mode is entered.
Rev. 1.20
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December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
Software Controlled LCD Driver
The devices have the capability of driving external LCD panels. The common pins,
SCOM0~SCOM3, and segment pins, SSEG0~SSEGm, where m is dependent upon which device is
selected, for LCD driving are pin-shared with certain pins on the I/O ports. The LCD signals (COM
and SEG) are generated using the application program.
LCD Operation
An external LCD panel can be driven using the devices by configuring the I/O pins as common pins
and segment pins. The LCD driver function is controlled using the LCD control registers which
in addition to controlling the overall on/off function also controls the R-type bias current on the
SCOMn and SSEGm pins. This enables the LCD COM driver to generate the necessary voltage
levels, VSS, (1/3)VDD, (2/3)VDD and VDD, for LCD 1/3 bias operation.
The LCDEN bit in the SLCDC0 register is the overall master control for the LCD driver. This bit
is used in conjunction with the corresponding pin-shared function selection bits, COMnEN and
SEGmEN, for the SCOMn and SSEGm pins to selecte which I/O pins are used for LCD driving.
Note that the corresponding Port Control register does not need to first setup the pins as outputs to
enable the LCD driver operation.
VDD
SEG�EN & COMnEN
pin-sha�ed sele�tion
VDD
SCOM0
(2/3) VDD
(1/3) VDD
SCOM3
LCD
COM/SEG
Analog Swit�h
LCD
Voltage
Sele�t
Ci��uit
SSEG0
SSEG�
�=1� fo� BS87B12A-3
�=19 fo� BS87C1�A-3
�=3� fo� BS87D20A-3
ISEL[1:0]
LCDEN
FRAME
Software Controlled LCD Driver Structure
Device
SCOM Pins
SSEG Pins
BS87B12A-3
SCOM0~SCOM3
SSEG0~SSEG15
BS87C16A-3
SCOM0~SCOM3
SSEG0~SSEG19
BS87D20A-3
SCOM0~SCOM3
SSEG0~SSEG35
Software Controlled LCD Driver Pins Summary
Rev. 1.20
172
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
LCD Frames
A cyclic LCD waveform includes two frames known as Frame 0 and Frame 1 for which the
following offers a functional explanation.
• Frame 0
To select Frame 0, clear the FRAME bit in the SLCDC 0 register to 0.
In frame 0, the COM signal output can have a value of VDD or a VBIAS value of (1/3)×VDD. The SEG
signal output can have a value of VSS or a VBIAS value of (2/3)×VDD.
• Frame 1
To select Frame 1, set the FRAME bit in the SLCDC0 register to 1.
In frame 1, the COM signal output can have a value of VSS or a VBIAS value of (2/3)×VDD. The SEG
signal output can have a value of VDD or a VBIAS value of (1/3)×VDD.
The COMn waveform is controlled by the application program using the FRAME bit in the
SLCDC0 register and the corresponding pin-shared I/O data bit for the respective SCOM pin to
determine whether the COMn output has a value of VDD, VSS or VBIAS. The SEGm waveform is
controlled in a similar way using the FRAME bit and the corresponding pin-shared I/O data bit for
the respective SSEG pin to determine whether the SEGm output has a value of VDD, VSS or VBIAS.
The accompanying waveform diagram shows a typical 1/3 bias LCD waveform generated using the
application program together with the LCD voltage select circuit. Note that the depiction of a "1" in
the diagram illustrates an illuminated LCD pixel. The COM and SEG signals polarity generated on
pins SCOMn and SSEGm, whether "0" or "1", are generated using the corresponding pin-shared I/O
data register bit.
Frame 0
COM0
0
0
0
Frame 0
Frame 1
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
0
0
1
1
0
0
0
0
0
1
1
1
0
0
1
1
1
1
1
VDD
(2/3) VDD
(1/3) VDD
VSS
VDD
(2/3) VDD
(1/3) VDD
VSS
1
VDD
(2/3) VDD
(1/3) VDD
VSS
0
1
VDD
(2/3) VDD
(1/3) VDD
VSS
VDD
(2/3) VDD
(1/3) VDD
VSS
0
1
VDD
(2/3) VDD
(1/3) VDD
VSS
1
1
1
0
0
1
0
1
1
0
1
0
0
1
0
1
1
0
1
0
0
1
1
0
1
0
SEG1
0
1
0
0
1
0
0
1
0
1
SEG0
0
0
1
0
0
1
1
0
0
1
0
0
0
0
0
1
0
1
0
0
0
1
COM3
0
1
1
0
0
0
1
COM2
0
1
0
0
0
0
0
1
1
0
0
0
1
1
0
0
1
0
1
COM1
0
Frame 0
Frame 0
Frame 1
1
1
Note: The logical value shown in the above diagram is the corresponding pin-shared I/O data bit value.
1/3 Bias LCD Waveform – 4-COM & 2-SEG Application
Rev. 1.20
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Touch A/D Flash MCU with OCVP
LCD Control Registers
The LCD COM and SEG driver enables a range of selections to be provided to suit the requirement
of the LCD panel which are being used. The bias current choice is implemented using the ISEL1
and ISEL0 bits in the SLCDC0 register. All COM and SEG pins are pin-shared with I/O pins and
selected as SCOMn and SSEGm pins using the corresponding pin-shared function selection bits.
Bit
Register
Name
7
6
5
4
SLCDC0
FRAME
ISEL1
ISEL0
LCDEN
SEG6EN
SEG5EN
SEG4EN
SLCDC1 SEG7EN
3
2
1
0
COM3EN COM2EN COM1EN COM0EN
SEG3EN
SEG2EN SEG1EN SEG0EN
SLCDC2 SEG15EN SEG14EN SEG13EN SEG12EN SEG11EN SEG10EN SEG9EN SEG8EN
Software Controlled LCD Registers List – BS87B12A-3
Bit
Register
Name
7
6
5
4
SLCDC0
FRAME
ISEL1
ISEL0
LCDEN
SEG6EN
SEG5EN
SEG4EN
SLCDC1 SEG7EN
3
2
1
0
COM3EN COM2EN COM1EN COM0EN
SEG1EN
SEG0EN
SLCDC2 SEG15EN SEG14EN SEG13EN SEG12EN SEG11EN SEG10EN SEG9EN
SEG8EN
SLCDC3
—
—
—
—
SEG3EN
SEG2EN
SEG19EN SEG18EN SEG17EN SEG16EN
Software Controlled LCD Registers List – BS87C16A-3
Bit
Register
Name
7
6
5
4
SLCDC0
FRAME
ISEL1
ISEL0
LCDEN
SEG6EN
SEG5EN
SEG4EN
SLCDC1 SEG7EN
3
2
1
0
COM3EN COM2EN COM1EN COM0EN
SEG1EN
SEG0EN
SLCDC2 SEG15EN SEG14EN SEG13EN SEG12EN SEG11EN SEG10EN SEG9EN
SEG3EN
SEG2EN
SEG8EN
SLCDC3 SEG23EN SEG22EN SEG21EN SEG20EN SEG19EN SEG18EN SEG17EN SEG16EN
SLCDC4 SEG31EN SEG30EN SEG29EN SEG28EN SEG27EN SEG26EN SEG25EN SEG24EN
SLCDC5
—
—
—
—
SEG35EN SEG34EN SEG33EN SEG32EN
Software Controlled LCD Registers List – BS87D20A-3
SLCDC0 Register
Rev. 1.20
Bit
7
6
5
4
Name
FRAME
ISEL1
ISEL0
LCDEN
3
2
1
0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
0
0
0
0
0
0
0
COM3EN COM2EN COM1EN COM0EN
Bit 7
FRAME: Frame 0 or Frame 1 outptu selection
0: Frame 0
1: Frame 1
Bit 6~5
ISEL1~ISEL0: SCOM/SSEG typical bias current selection (@VDD=5V)
00: 8.3μA
01: 16.7μA
10: 50μA
11: 100μA
Bit 4
LCDEN: Software controlled LCD Driver enable control
0: Disable
1: Enable
The SCOMn and SSEGm lines can be enabled using the corresponding pin-shared
selection bits, COMnEN and SEGmEN, if the LCDEN bit is set to 1. When the
LCDEN bit is cleared to 0, then the SCOMn and SSEGm outputs will be fixed at a VSS
level. Note that the corresponding pin-shared selection bits should first be properly
configured before the SCOMn or SSEGm function is enabled.
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Touch A/D Flash MCU with OCVP
Bit 3
COM3EN: SCOM3 pin function control
0: Disable – I/O or other pin-shared functions
1: Enable – SCOM3
Bit 2
COM2EN: SCOM2 pin function control
0: Disable – I/O or other pin-shared functions
1: Enable – SCOM2
Bit 1
COM1EN: SCOM1 pin function control
0: Disable – I/O or other pin-shared functions
1: Enable – SCOM1
Bit 0
COM0EN: SCOM0 pin function control
0: Disable – I/O or other pin-shared functions
1: Enable – SCOM0
SLCDC1 Register
Bit
Name
7
6
5
4
3
2
1
0
SEG7EN SEG6EN SEG5EN SEG4EN SEG3EN SEG2EN SEG1EN SEG0EN
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
0
0
0
0
0
0
0
1
0
Bit 7~0
SEG7EN~SEG0EN: SSEG7~SSEG0 individual pin function control
0: Disable – I/O or other pin-shared functions
1: Enable – SSEG7~SSEG0
SLCDC2 Register
Bit
Name
7
6
5
4
3
2
SEG15EN SEG14EN SEG13EN SEG12EN SEG11EN SEG10EN SEG9EN SEG8EN
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
SEG15EN~SEG8EN: SSEG15~SSEG8 individual pin function control
0: Disable – I/O or other pin-shared functions
1: Enable – SSEG15~SSEG8
SLCDC3 Register – BS87C16A-3
Bit
7
6
5
4
Name
—
—
—
—
3
2
1
0
R/W
—
—
—
—
R/W
R/W
R/W
R/W
POR
—
—
—
—
0
0
0
0
SEG19EN SEG18EN SEG17EN SEG16EN
Bit 7~4
Unimplemented, read as "0"
Bit 3~0
SEG19EN~SEG16EN: SSEG19~SSEG16 individual pin function control
0: Disable – I/O or other pin-shared functions
1: Enable – SSEG19~SSEG16
SLCDC3 Register – BS87D20A-3
Bit
7
6
5
4
3
2
1
0
Name SEG23EN SEG22EN SEG21EN SEG20EN SEG19EN SEG18EN SEG17EN SEG16EN
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. 1.20
SEG23EN~SEG16EN: SSEG23~SSEG16 individual pin function control
0: Disable – I/O or other pin-shared functions
1: Enable – SSEG23~SSEG16
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Touch A/D Flash MCU with OCVP
SLCDC4 Register – BS87D20A-3
Bit
7
6
5
4
3
2
1
0
Name SEG31EN SEG30EN SEG29EN SEG28EN SEG27EN SEG26EN SEG25EN SEG24EN
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
SEG31EN~SEG24EN: SSEG31~SSEG24 individual pin function control
0: Disable – I/O or other pin-shared functions
1: Enable – SSEG31~SSEG24
SLCDC5 Register – BS87D20A-3
Rev. 1.20
Bit
7
6
5
4
Name
—
—
—
—
3
2
1
R/W
—
—
—
—
R/W
R/W
R/W
R/W
POR
—
—
—
—
0
0
0
0
Bit 7~4
Unimplemented, read as "0"
Bit 3~0
SEG35EN~SEG32EN: SSEG35~SSEG32 individual pin function control
0: Disable – I/O or other pin-shared functions
1: Enable – SSEG35~SSEG32
176
0
SEG35EN SEG34EN SEG33EN SEG32EN
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
Low Voltage Detector – LVD
Each device has a Low Voltage Detector function, also known as LVD. This enabled the device to
monitor the power supply voltage, VDD, and provide a warning signal should it fall below a certain
level. This function may be especially useful in battery applications where the supply voltage will
gradually reduce as the battery ages, as it allows an early warning battery low signal to be generated.
The Low Voltage Detector also has the capability of generating an interrupt signal.
LVD Register
The Low Voltage Detector function is controlled using a single register with the name LVDC. Three
bits in this register, VLVD2~VLVD0, are used to select one of five 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
Rev. 1.20
Bit
7
6
5
4
3
2
1
0
Name
—
—
LVDO
LVDEN
VBGEN
VLVD2
VLVD1
VLVD0
R/W
—
—
R
R/W
R/W
R/W
R/W
R/W
POR
—
—
0
0
0
0
0
0
Bit 7~6
Unimplemented, read as "0"
Bit 5
LVDO: LVD output flag
0: No Low Voltage Detected
1: Low Voltage Detected
Bit 4
LVDEN: Low Voltage Detector Enable control
0: Disable
1: Enable
Bit 3
VBGEN: Bandgap Voltage Output Enable control
0: Disable
1: Enable
Bit 2~0
VLVD2~VLVD0: LVD Voltage selection
000: 2.0V
001: 2.2V
010: 2.4V
011: 2.7V
100: 3.0V
101: 3.3V
110: 3.6V
111: 4.0V
Since the VLVR is fixed at 2.55V, the VLVD should be set to 2.7V~4.0V.
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Touch A/D Flash MCU with OCVP
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 2.7V and 4.0V.
When the power supply voltage, VDD, falls below this pre-determined value, the LVDO bit will be
set high indicating a low power supply voltage condition. The Low Voltage Detector function is
supplied by a reference voltage which will be automatically enabled. When the device is powered
down the low voltage detector will remain active if the LVDEN bit is high. After enabling the Low
Voltage Detector, a time delay tLVDS should be allowed for the circuitry to stabilise before reading the
LVDO bit. Note also that as the VDD voltage may rise and fall rather slowly, at the voltage nears that
of VLVD, there may be multiple bit LVDO transitions.
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. When the device is powered down the Low Voltage Detector
will remain active if the LVDEN bit is high. In this case, the LVF interrupt request flag will be set,
causing an interrupt to be generated if VDD falls below the preset LVD voltage. This will cause the
device to wake-up from the SLEEP or IDLE Mode, however if the Low Voltage Detector wake up
function is not required then the LVF flag should be first set high before the device enters the SLEEP
or IDLE Mode.
Rev. 1.20
178
December 05, 2016
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Touch A/D Flash MCU with OCVP
Interrupts
Interrupts are an important part of any microcontroller system. When an external event or an
internal function such as a Timer Module or an A/D converter requires microcontroller attention,
their corresponding interrupt will enforce a temporary suspension of the main program allowing the
microcontroller to direct attention to their respective needs. These devices contain several external
interrupt and internal interrupts functions. The external interrupts are generated by the action of the
external INT0 ~ INT3 pins, while the internal interrupts are generated by various internal functions
such as the TMs, Time Base, LVD, EEPROM, SIM, UART and the A/D converter, etc.
Interrupt Registers
Overall interrupt control, which basically means the setting of request flags when certain
microcontroller conditions occur and the setting of interrupt enable bits by the application program,
is controlled by a series of registers, located in the Special Purpose Data Memory, as shown in the
accompanying table. The number of registers depends upon the device chosen but fall into three
categories. The first is the INTC0~INTC3 registers which setup the primary interrupts, the second
is the MFI 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 interrupts as well
as interrupt flags to indicate the presence of an interrupt request. The naming convention of these
follows a specific pattern. First is listed an abbreviated interrupt type, then the (optional) number of
that interrupt followed by either an "E" for enable/disable bit or "F" for request flag.
Function
Enable Bit
Request Flag
Notes
—
Global
EMI
—
INT Pin
INTE
INTF
—
Touch Key Module
TKME
TKMF
—
OCVPE
OCVPF
Multi-function
OCVP
MFE
MFF
SIM
SIME
SIMF
—
EEPROM write operation
DEE
DEF
—
—
UART
—
For BS87C16A-3 & BS87D20A-3 only
URnE
URnF
LVD
LVE
LVF
—
A/D Converter
ADE
ADF
—
Time Base
PTM
CTM
TBnE
TBnF
PTMnPE
PTMnPF
PTMnAE
PTMnAF
CTMnPE
CTMnPF
CTMnAE
CTMnAF
n=0 ~ 1
n=0 for BS87B12A-3
n=0 ~ 1 for BS87C16A-3 & BS87D20A-3
n=0 for BS87B12A-3 & BS87C16A-3
n=0 ~ 1 for BS87D20A-3
Interrupt Register Bit Naming Conventions
Bit
Register
Name
7
6
5
4
3
2
1
0
INTEG
—
—
—
—
—
—
INTS1
INTS0
TKME
INTE
EMI
INTC0
—
OCVPF
TKMF
INTF
OCVPE
INTC1
PTM0AF
PTM0PF
CTM0AF
CTM0PF
PTM0AE
PTM0PE CTM0AE CTM0PE
INTC2
URF
DEF
SIMF
—
URE
DEE
SIME
—
INTC3
TB1F
TB0F
ADF
LVF
TB1E
TB0E
ADE
LVE
Interrupt Registers List – BS87B12A-3
Rev. 1.20
179
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
Bit
Register
Name
7
6
5
4
3
2
1
0
INTEG
—
—
—
—
—
—
INTS1
INTS0
INTE
EMI
INTC0
—
OCVPF
TKMF
INTF
OCVPE
TKME
INTC1
PTM0AF
PTM0PF
CTM0AF
CTM0PF
PTM0AE
PTM0PE
CTM0AE CTM0PE
INTC2
URF
DEF
SIMF
MFF
URE
DEE
SIME
MFE
INTC3
TB1F
TB0F
ADF
LVF
TB1E
TB0E
ADE
LVE
MFI
—
—
PTM1AF
PTM1PF
—
—
PTM1AE
PTM1PE
Interrupt Registers List – BS87C16A-3
Bit
Register
Name
7
6
5
4
3
2
1
0
INTEG
—
—
—
—
—
—
INTS1
INTS0
INTE
EMI
INTC0
—
OCVPF
TKMF
INTF
OCVPE
TKME
INTC1
PTM0AF
PTM0PF
CTM0AF
CTM0PF
PTM0AE
PTM0PE
CTM0AE CTM0PE
INTC2
URF
DEF
SIMF
MFF
URE
DEE
SIME
INTC3
TB1F
TB0F
ADF
LVF
TB1E
TB0E
ADE
LVE
MFI
CTM1AF
CTM1PF
PTM1AF
PTM1PF
PTM1AE
PTM1PE
CTM1AE CTM1PE
MFE
Interrupt Registers List – BS87D20A-3
INTEG Register
Bit
7
6
5
4
3
2
1
0
Name
—
—
—
—
—
—
INTS1
INTS0
R/W
—
—
—
—
—
—
R/W
R/W
POR
—
—
—
—
—
—
0
0
Bit 7~2
Unimplemented, read as "0"
Bit 1~0
INTS1~INTS0: Interrupt edge control for INT pin
00: Disable
01: Rising edge
10: Falling edge
11: Rising and falling edges
INTC0 Register
Rev. 1.20
Bit
7
6
5
4
3
2
1
0
Name
—
OCVPF
TKMF
INTF
OCVPE
TKME
INTE
EMI
R/W
—
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
—
0
0
0
0
0
0
0
Bit 7
Unimplemented, read as "0"
Bit 6
OCVPF: OCVP interrupt request flag
0: no request
1: interrupt request
Bit 5
TKMF: Touch key module interrupt request flag
0: No request
1: Interrupt request
Bit 4
INTF: INT interrupt request flag
0: No request
1: Interrupt request
Bit 3
OCVPE: OCVP interrupt control
0: Disable
1: Enable
180
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
Bit 2
TKME: Touch key module interrupt control
0: Disable
1: Enable
Bit 1
INTE: INT interrupt control
0: Disable
1: Enable
Bit 0
EMI: Global interrupt control
0: Disable
1: Enable
INTC1 Register
Bit
7
6
5
4
3
2
Name
PTM0AF
PTM0PF
CTM0AF
CTM0PF
PTM0AE
PTM0PE
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
PTM0AF: PTM0 Comparator A match Interrupt request flag
0: No request
1: Interrupt request
Bit 6
PTM0PF: PTM0 Comparator P match Interrupt request flag
0: No request
1: Interrupt request
Bit 5
CTM0AF: CTM0 Comparator A match Interrupt request flag
0: No request
1: Interrupt request
Bit 4
CTM0PF: CTM0 Comparator P match Interrupt request flag
0: No request
1: Interrupt request
Bit 3
PTM0AE: PTM0 Comparator A match Interrupt control
0: Disable
1: Enable
Bit 2
PTM0PE: PTM0 Comparator P match Interrupt control
0: Disable
1: Enable
Bit 1
CTM0AE: CTM0 Comparator A match Interrupt control
0: Disable
1: Enable
Bit 0
CTM0PE: CTM0 Comparator P match Interrupt control
0: Disable
1: Enable
1
0
CTM0AE CTM0PE
INTC2 Register – BS87B12A-3
Rev. 1.20
Bit
7
6
5
4
3
2
1
0
Name
URF
DEF
SIMF
—
URE
DEE
SIME
—
R/W
R/W
R/W
R/W
—
R/W
R/W
R/W
—
POR
0
0
0
—
0
0
0
—
Bit 7
URF: UART transfer interrupt request flag
0: No request
1: Interrupt request
Bit 6
DEF: Data EEPROM Interrupt request flag
0: No request
1: Interrupt request
181
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
Bit 5
SIMF: SIM Interrupt request flag
0: No request
1: Interrupt request
Bit 4
Unimplemented, read as "0"
Bit 3
URE: UART transfer interrupt control
0: Disable
1: Enable
Bit 2
DEE: Data EEPROM Interrupt control
0: Disable
1: Enable
Bit 1
SIME: SIM Interrupt control
0: Disable
1: Enable
Bit 0
Unimplemented, read as "0"
INTC2 Register – BS87C16A-3 & BS87D20A-3
Rev. 1.20
Bit
7
6
5
4
3
2
1
0
Name
URF
DEF
SIMF
MFF
URE
DEE
SIME
MFE
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
URF: UART transfer interrupt request flag
0: No request
1: Interrupt request
Bit 6
DEF: Data EEPROM Interrupt request flag
0: No request
1: Interrupt request
Bit 5
SIMF: SIM Interrupt request flag
0: No request
1: Interrupt request
Bit 4
MFF: Multi-function interrupt request flag
0: No request
1: Interrupt request
Bit 3
URE: UART transfer interrupt control
0: Disable
1: Enable
Bit 2
DEE: Data EEPROM Interrupt control
0: Disable
1: Enable
Bit 1
SIME: SIM Interrupt control
0: Disable
1: Enable
Bit 0
MFE: Multi-function interrupt control
0: Disable
1: Enable
182
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Touch A/D Flash MCU with OCVP
INTC3 Register
Bit
7
6
5
4
3
2
1
0
Name
TB1F
TB0F
ADF
LVF
TB1E
TB0E
ADE
LVE
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
0
0
0
0
0
0
0
Bit 7
TB1F: Time Base 1 interrupt request flag
0: No request
1: Interrupt request
Bit 6
TB0F: Time Base 0 interrupt request flag
0: No request
1: Interrupt request
Bit 5
ADF: A/D Converter interrupt request flag
0: No request
1: Interrupt request
Bit 4
LVF: LVD Interrupt request flag
0: No request
1: Interrupt request
Bit 3
TB1E: Time Base 1 interrupt control
0: Disable
1: Enable
Bit 2
TB0E: Time Base 0 interrupt control
0: Disable
1: Enable
Bit 1
ADE: A/D Converter interrupt control
0: Disable
1: Enable
Bit 0
LVE: LVD Interrupt control
0: Disable
1: Enable
MFI Register – BS87C16A-3
Rev. 1.20
Bit
7
6
5
4
3
2
1
0
Name
—
—
PTM1AF
PTM1PF
—
—
PTM1AE
PTM1PE
R/W
—
—
R/W
R/W
—
—
R/W
R/W
POR
—
—
0
0
—
—
0
0
Bit 7~6
Unimplemented, read as "0"
Bit 5
PTM1AF: PTM1 Comparator A match Interrupt request flag
0: No request
1: Interrupt request
Bit 4
PTM1PF: PTM1 Comparator P match Interrupt request flag
0: No request
1: Interrupt request
Bit 3~2
Unimplemented, read as "0"
Bit 1
PTM1AE: PTM1 Comparator A match Interrupt control
0: Disable
1: Enable
Bit 0
PTM1PE: PTM1 Comparator P match Interrupt control
0: Disable
1: Enable
183
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
MFI Register – BS87D20A-3
Rev. 1.20
Bit
7
6
5
4
Name
CTM1AF
CTM1PF
PTM1AF
PTM1PF
3
R/W
R/W
R/W
R/W
R/W
R/W
POR
0
0
0
0
0
2
1
0
PTM1AE
PTM1PE
R/W
R/W
R/W
0
0
0
CTM1AE CTM1PE
Bit 7
CTM1AF: CTM1 Comparator A match Interrupt request flag
0: No request
1: Interrupt request
Bit 6
CTM1PF: CTM1 Comparator P match Interrupt request flag
0: No request
1: Interrupt request
Bit 5
PTM1AF: PTM1 Comparator A match Interrupt request flag
0: No request
1: Interrupt request
Bit 4
PTM1PF: PTM1 Comparator P match Interrupt request flag
0: No request
1: Interrupt request
Bit 3
CTM1AE: CTM1 Comparator A match Interrupt control
0: Disable
1: Enable
Bit 2
CTM1PE: CTM1 Comparator P match Interrupt control
0: Disable
1: Enable
Bit 1
PTM1AE: PTM1 Comparator A match Interrupt control
0: Disable
1: Enable
Bit 0
PTM1PE: PTM1 Comparator P match Interrupt control
0: Disable
1: Enable
184
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Touch A/D Flash MCU with OCVP
Interrupt Operation
When the conditions for an interrupt event occur, such as a Touch Key Counter overflow, a TM
Comparator P or Comparator A match or A/D conversion completion, etc, the relevant interrupt
request flag will be set. Whether the request flag actually generates a program jump to the relevant
interrupt vector is determined by the condition of the interrupt enable bit. If the enable bit is set high
then the program will jump to its relevant vector; if the enable bit is zero then although the interrupt
request flag is set an actual interrupt will not be generated and the program will not jump to the
relevant interrupt vector. The global interrupt enable bit, if cleared to zero, will disable all interrupts.
When an interrupt is generated, the Program Counter, which stores the address of the next instruction
to be executed, will be transferred onto the stack. The Program Counter will then be loaded with a
new address which will be the value of the corresponding interrupt vector. The microcontroller will
then fetch its next instruction from this interrupt vector. The instruction at this vector will usually
be a JMP which will jump to another section of program which is known as the interrupt service
routine. Here is located the code to control the appropriate interrupt. The interrupt service routine
must be terminated with a RETI, which retrieves the original Program Counter address from the
stack and allows the microcontroller to continue with normal execution at the point where the
interrupt occurred.
The various interrupt enable bits, together with their associated request flags, are shown in the
accompanying diagrams with their order of priority. Some interrupt sources have their own
individual vector while others share the same multi-function interrupt vector. Once an interrupt
subroutine is serviced, all other interrupts will be blocked, as the global interrupt enable bit, EMI
bit will be cleared automatically. This will prevent any further interrupt nesting from occurring.
However, if other interrupt requests occur during this interval, although the interrupt will not be
immediately serviced, the request flag will still be recorded.
If an interrupt requires immediate servicing while the program is already in another interrupt service
routine, the EMI bit should be set after entering the routine to allow interrupt nesting. If the stack
is full, the interrupt request will not be acknowledged, even if the related interrupt is enabled, until
the Stack Pointer is decremented. If immediate service is desired, the stack must be prevented from
becoming full. In case of simultaneous requests, the accompanying diagram shows the priority that
is applied. All of the interrupt request flags when set will wake-up the device if it is in SLEEP or
IDLE Mode, however to prevent a wake-up from occurring the corresponding flag should be set
before the device is in SLEEP or IDLE Mode.
Rev. 1.20
185
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
EMI auto disa�led in ISR
Inte��upt
Na�e
Request
Flags
Ena�le
Bits
Maste�
Ena�le
INT Pin
INTF
INTE
EMI
Tou�h Key Module
TKMF
TKME
EMI
08H
OCVP
OCVPF
OCVPE
EMI
0CH
CTM0 Co�p. P
CTM0PF
CTM0PE
EMI
10H
CTM0 Co�p. A
CTM0AF
CTM0AE
EMI
14H
PTM0 Co�p. P
PTM0PF
PTM0PE
EMI
18H
PTM0 Co�p. A
PTM0AF
PTM0AE
EMI
1CH
Vector P�io�ity
High
04H
20H
SIM
SIMF
SIME
EMI
24H
EEPROM
DEF
DEE
EMI
28H
UART
URF
URE
EMI
2CH
LVD
LVF
LVE
EMI
30H
A/D
ADF
ADE
EMI
34H
Ti�e Base 0
TB0F
TB0E
EMI
38H
Ti�e Base 1
TB1F
TB1E
EMI
3CH
Low
Interrupt Structure – BS87B12A-3
Rev. 1.20
186
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
EMI auto disa�led in ISR
Inte��upt
Na�e
Request
Flags
Ena�le
Bits
Maste�
Ena�le
INT Pin
INTF
INTE
EMI
04H
Tou�h Key Module
TKMF
TKME
EMI
08H
OCVP
OCVPF
OCVPE
EMI
0CH
CTM0 Co�p. P
CTM0PF
CTM0PE
EMI
10H
CTM0 Co�p. A
CTM0AF
CTM0AE
EMI
14H
PTM0 Co�p. P
PTM0PF
PTM0PE
EMI
18H
Vector P�io�ity
High
Legend
xxF
Request Flag� no auto �eset in ISR
xxF
Request Flag� auto �eset in ISR
xxE
Ena�le Bits
Inte��upts �ontained within
Multi-Fun�tion Inte��upts
Inte��upt
Na�e
Request
Flags
Ena�le
Bits
PTM0 Co�p. A
PTM0AF
PTM0AE
EMI
1CH
PTM1 Co�p. P
PTM1PF
PTM1PE
Multi-Fun�tion
MFF
MFE
EMI
20H
PTM1 Co�p. A
PTM1AF
PTM1AE
SIM
SIMF
SIME
EMI
24H
EEPROM
DEF
DEE
EMI
28H
UART
URF
URE
EMI
2CH
LVD
LVF
LVE
EMI
30H
A/D
ADF
ADE
EMI
34H
Ti�e Base 0
TB0F
TB0E
EMI
38H
Ti�e Base 1
TB1F
TB1E
EMI
3CH
Low
Interrupt Structure – BS87C16A-3
Rev. 1.20
187
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
EMI auto disa�led in ISR
Legend
xxF
Request Flag� no auto �eset in ISR
xxF
Request Flag� auto �eset in ISR
xxE
Ena�le Bits
Inte��upts �ontained within
Multi-Fun�tion Inte��upts
Inte��upt
Na�e
Request
Flags
Ena�le
Bits
CTM1 Co�p. P
CTM1PF
CTM1PE
CTM1 Co�p. A
CTM1AF
CTM1AE
PTM1 Co�p. P
PTM1PF
PTM1PE
PTM1 Co�p. A
PTM1AF
PTM1AE
Inte��upt
Na�e
Request
Flags
Ena�le
Bits
Maste�
Ena�le
INT Pin
INTF
INTE
EMI
04H
Tou�h Key Module
TKMF
TKME
EMI
08H
OCVP
OCVPF
OCVPE
EMI
0CH
CTM0 Co�p. P
CTM0PF
CTM0PE
EMI
10H
CTM0 Co�p. A
CTM0AF
CTM0AE
EMI
14H
PTM0 Co�p. P
PTM0PF
PTM0PE
EMI
18H
PTM0 Co�p. A
PTM0AF
PTM0AE
EMI
1CH
Multi-Fun�tion
MFF
MFE
EMI
20H
SIM
SIMF
SIME
EMI
24H
EEPROM
DEF
DEE
EMI
28H
UART
URF
URE
EMI
2CH
LVD
LVF
LVE
EMI
30H
A/D
ADF
ADE
EMI
34H
Ti�e Base 0
TB0F
TB0E
EMI
38H
Ti�e Base 1
TB1F
TB1E
EMI
3CH
Vector P�io�ity
High
Low
Interrupt Structure – BS87D20A-3
Rev. 1.20
188
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
External Interrupt
The external interrupt is controlled by signal transitions on the pin INT. An external interrupt
request will take place when the external interrupt request flag, INTF, is set, which will occur when
a transition, whose type is chosen by the edge select bits, appears on the external interrupt pin. To
allow the program to branch to its respective interrupt vector address, the global interrupt enable bit,
EMI, and respective external interrupt enable bit, INTE, must first be set. Additionally the correct
interrupt edge type must be selected using the INTEG register to enable the external interrupt
function and to choose the trigger edge type. As the external interrupt pin is pin-shared with I/O
pins, they can only be configured as an external interrupt pin if the external interrupt enable bit in
the corresponding interrupt register has been set. The pin must also be setup as an input by setting
the corresponding bit in the port control register. When the interrupt is enabled, the stack is not full
and the correct transition type appears on the external interrupt pin, a subroutine call to the external
interrupt vector, will take place. When the interrupt is serviced, the external interrupt request flags,
INTF, 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.
Touch Key Module Interrupt
For a Touch Key interrupt to occur, the global interrupt enable bit, EMI, and the Touch Key interrupt
enable bit, TKME, must be first set. An actual Touch Key interrupt will take place when the Touch
Key interrupt request flag, TKMF, is set, a situation that will occur when the time slot counter
overflows. When the interrupt is enabled, the stack is not full and the Touch Key time slot counter
overflow occurs, a subroutine call to the relevant interrupt vector, will take place. When the interrupt
is serviced, the Touch Key interrupt request flag will be automatically reset and the EMI bit will also
be automatically cleared to disable other interrupts.
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 automatically
be cleared to disable other interrupts and the OCVP interrupt request flag will also be automatically
cleared.
TM Interrupts
The Compact and Periodic TMs have two interrupts, one comes from the comparator A match
situation and the other comes from the comparator P match situation. The CTM0 and PTM0
interrupts have their own individual interrupt vectors respectively while the CTM1 and PTM1 are
contained within the Multi-function Interrupts. For the CTM0 and PTM0 there are two interrupt
request flags and two enable control bits. A TM interrupt request will take place when any of the
TM request flags are set, a situation which occurs when a TM comparator P or A match situation
happens.
Rev. 1.20
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BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
To allow the program to branch to its respective interrupt vector address, the global interrupt enable
bit, EMI, and respective TM Interrupt enable bit must first be set for CTM0 and PTM0. However,
the relevant Multi-function Interrupt enable bit, MFE, must also be set for CTM1 or PTM1.
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. The CTM0 or
PTM0 interrupt request flag will automatically be cleared. However, for CTM1 or PTM1 only the
related MFF flag will be automatically cleared. The CTM1 or PTM1 interrupt request flags will be
kept unchanged. As the CTM or PTM1 interrupt request flags will not be automatically cleared, they
have to be cleared by the application program.
Multi-function Interrupt – BS87C16A-3 & BS87D20A-3
Within the specific device there is one Multi-function interrupts. Unlike the other independent
interrupts, this interrupt has no independent source, but rather are formed from other existing
interrupt sources, namely the PTM1 or CTM1/PTM1 interrupts, dependent upon which device is
selected.
A Multi-function interrupt request will take place when the Multi-function interrupt request flag
MFF are set. The Multi-function interrupt flag will be set when any of its included functions
generate an interrupt request flag. To allow the program to branch to its respective interrupt vector
address, when the Multi-function interrupt is enabled and the stack is not full, and one of the
interrupts contained within the Multi-function interrupt occurs, a subroutine call to one of the Multifunction interrupt vectors will take place. When the interrupt is serviced, the related Multi-Function
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 request flag will be
automatically reset when the interrupt is serviced, the request flags from the original source of
the Multi-function interrupt will not be automatically reset and must be manually reset by the
application program.
Serial Interface Module Interrupt
The Serial Interface Module Interrupt, also known as the SIM interrupt, is an individual interrupt
source with its own interrupt vector. A SIM Interrupt request will take place when the SIM Interrupt
request flag, SIMF, is set, which occurs when a byte of data has been received or transmitted by the
SIM interface, an I2C slave address match or I2C bus time-out happens. To allow the program to
branch to its respective interrupt vector address, the global interrupt enable bit, EMI, and the Serial
Interface Interrupt enable bit, SIME, must first be set. When the interrupt is enabled, the stack is
not full and any of the above described situations occurs, a subroutine call to the corresponding
iInterrupt vector will take place. When the Serial Interface Interrupt is serviced, the SIM interrupt
request flag, SIMF, will be automatically cleared and the EMI bit will also be automatically cleared
to disable other interrupts.
Rev. 1.20
190
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
EEPROM Interrupt
The EEPROM Write Interrupt is an individual interrupt source with its own interrupt vector. An
EEPROM Write Interrupt request will take place when the EEPROM Write 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 Write
Interrupt enable bit, DEE, 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 interrupt vector will take place. When
the EEPROM Write Interrupt is serviced, the DEF flag will be automatically cleared and the EMI bit
will also be automatically cleared to disable other interrupts.
UART Transfer Interrupt
The UART Transfer Interrupt is controlled by several UART transfer conditions. When one of these
conditions occurs, an interrupt pulse will be generated to get the attention of the microcontroller.
These conditions are a transmitter data register empty, transmitter idle, receiver data available,
receiver overrun, address detect and an RX pin wake-up. To allow the program to branch to its
respective interrupt vector address, the global interrupt enable bit, EMI, and UART Interrupt
enable bit, URE, must first be set. When the interrupt is enabled, the stack is not full and any of the
conditions described above occurs, a subroutine call to the UART Interrupt vector, will take place.
When the interrupt is serviced, the UART Interrupt flag, URF, will be automatically cleared. The
EMI bit will also be automatically cleared to disable other interrupts.
LVD Interrupt
The Low Voltage Detector Interrupt is an individual interrupt source with its own interrupt cevtor.
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, 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 relevant interrupt vector will
take place. When the Low Voltage Interrupt is serviced, the LVF flag will be automatically cleared.
The EMI bit will also be automatically cleared to disable other interrupts.
A/D Converter Interrupt
The A/D Converter Interrupt is controlled by the termination of an A/D conversion process. An A/
D Converter Interrupt request will take place when the A/D Converter Interrupt request flag, ADF,
is set, which occurs when the A/D conversion process finishes. To allow the program to branch to its
respective interrupt vector address, the global interrupt enable bit, EMI, and A/D Interrupt enable bit,
ADE, must first be set. When the interrupt is enabled, the stack is not full and the A/D conversion
process has ended, a subroutine call to the A/D Converter Interrupt vector will take place. When the
interrupt is serviced, the A/D Converter Interrupt flag, ADF, will be automatically cleared. The EMI
bit will also be automatically cleared to disable other interrupts.
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Time Base Interrupts
The function of the Time Base Interrupt is to provide regular time signal in the form of an internal
interrupt. It is controlled by the overflow signal from its internal timer. When this happens its
interrupt request flag, TBnF, will be set. To allow the program to branch to its respective interrupt
vector addresses, the global interrupt enable bit, EMI and Time Base enable bit, TBnE, must first be
set. When the interrupt is enabled, the stack is not full and the Time Base overflows, a subroutine
call to its respective vector location will take place. When the interrupt is serviced, the interrupt
request flag, TBnF, 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. Its
clock source, fPSC0 or fPSC1, originates from the internal clock source fSYS, fSYS/4, fSUB or fH and then
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 which in
turn controls the Time Base interrupt period is selected using the CLKSEL0[1:0] and CLKSEL1[1:0]
bits in the PSCR register respectively.
fSYS
fSYS/4
fSUB
fH
M
U
X
fPSC0
P�es�ale� 0
TB0ON
fPSC0/28 ~ fPSC0/21�
M
U
X
TB0[2:0]
CLKSEL0[1:0]
fSYS
fSYS/4
fSUB
fH
M
U
X
fPSC1
Ti�e Base 0 Inte��upt
P�es�ale� 1
fPSC1/28 ~ fPSC1/21�
M
U
X
TB1ON
CLKSEL1[1:0]
Ti�e Base 1 Inte��upt
TB1[2:0]
Time Base Interrupts
PSCR Register
Rev. 1.20
Bit
7
6
Name
—
—
5
R/W
—
—
R/W
POR
—
—
0
4
3
2
1
0
—
—
CLKSEL01
CLKSEL00
R/W
—
—
R/W
R/W
0
—
—
0
0
CLKSEL11 CLKSEL10
Bit 7~6
unimplemented, read as "0"
Bit 5~4
CLKSEL11~CLKSEL10: Prescaler 1 clock source fPSC1 selection
00: fSYS
01: fSYS/4
10: fSUB
11: fH
Bit 3~2
unimplemented, read as "0"
Bit 1~0
CLKSEL01~CLKSEL00: Prescaler 0 clock source fPSC0 selection
00: fSYS
01: fSYS/4
10: fSUB
11: fH
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TBC Register
Bit
7
6
5
4
3
2
1
0
Name
TB1ON
TB12
TB11
TB10
TB0ON
TB02
TB01
TB00
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
TB1ON: Time Base 1 Enable Control
0: Disable
1: Enable
Bit 6~4
TB12~TB10: Time Base 1 time-out period selection
000: 28/fPSC1
001: 29/fPSC1
010: 210/fPSC1
011: 211/fPSC1
100: 212/fPSC1
101: 213/fPSC1
110: 214/fPSC1
111: 215/fPSC1
Bit 3
TB0ON: Time Base 0 Enable Control
0: Disable
1: Enable
Bit 2~0
TB02~TB00: Time Base 0 time-out period selection
000: 28/fPSC0
001: 29/fPSC0
010: 210/fPSC0
011: 211/fPSC0
100: 212/fPSC0
101: 213/fPSC0
110: 214/fPSC0
111: 215/fPSC0
Interrupt Wake-up Function
Each of the interrupt functions has the capability of waking up the microcontroller when in the
SLEEP or IDLE Mode. A wake-up is generated when an interrupt request flag changes from low
to high and is independent of whether the interrupt is enabled or not. Therefore, even though these
devices are in the SLEEP or IDLE Mode and its system oscillator stopped, situations such as
external edge transitions on the external interrupt pins, a low power supply voltage or comparator
input change may cause their respective interrupt flag to be set high and consequently generate
an interrupt. Care must therefore be taken if spurious wake-up situations are to be avoided. If an
interrupt wake-up function is to be disabled then the corresponding interrupt request flag should be
set high before the device enters the SLEEP or IDLE Mode. The interrupt enable bits have no effect
on the interrupt wake-up function.
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Programming Considerations
By disabling the relevant interrupt enable bits, a requested interrupt can be prevented from being
serviced, however, once an interrupt request flag is set, it will remain in this condition in the
interrupt register until the corresponding interrupt is serviced or until the request flag is cleared by
the application program.
Where a certain interrupt is contained within a Multi-function interrupt, then when the interrupt
service routine is executed, as only the Multi-function interrupt request flags, MFnF, will be
automatically cleared, the individual request flag for the function needs to be cleared by the
application program.
It is recommended that programs do not use the "CALL" instruction within the interrupt service
subroutine. Interrupts often occur in an unpredictable manner or need to be serviced immediately.
If only one stack is left and the interrupt is not well controlled, the original control sequence will be
damaged once a CALL subroutine is executed in the interrupt subroutine.
Every interrupt has the capability of waking up the microcontroller when it is in the SLEEP or IDLE
Mode, the wake up being generated when the interrupt request flag changes from low to high. If it is
required to prevent a certain interrupt from waking up the microcontroller then its respective request
flag should be first set high before enter SLEEP or IDLE Mode.
As only the Program Counter is pushed onto the stack, then when the interrupt is serviced, if the
contents of the accumulator, status register or other registers are altered by the interrupt service
program, their contents should be saved to the memory at the beginning of the interrupt service
routine.
To return from an interrupt subroutine, either a RET or RETI instruction may be executed. The RETI
instruction in addition to executing a return to the main program also automatically sets the EMI
bit high to allow further interrupts. The RET instruction however only executes a return to the main
program leaving the EMI bit in its present zero state and therefore disabling the execution of further
interrupts.
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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
Oscillator Option
1
Low Speed System Oscillator Selection – fSUB:
LIRC or LXT
2
HIRC Frequency Selection – fHIRC:
8MHz, 12MHz or 16MHz
Note that when the HIRC has been configured at a frequency shown in this table the HIRCS1 and
HIRCS0 bits are recommended to be setup to select the same frequency to keep the HIRC frequency
accuracy specified in the A.C characteristics.
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Application Circuits
VDD
I/O Pins
VDD
AN0~AN7
0.1uF
VSS
SIM Pins
UART Pins
SCOM&SSEG
Pins
KEY1
KEY2
OCVP Pins
XT1
KEYn
XT2
OSC
Ci��uit
See Os�illato�
Se�tion
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Instruction Set
Introduction
Central to the successful operation of any microcontroller is its instruction set, which is a set of
program instruction codes that directs the microcontroller to perform certain operations. In the case
of Holtek microcontroller, a comprehensive and flexible set of over 60 instructions is provided to
enable programmers to implement their application with the minimum of programming overheads.
For easier understanding of the various instruction codes, they have been subdivided into several
functional groupings.
Instruction Timing
Most instructions are implemented within one instruction cycle. The exceptions to this are branch,
call, or table read instructions where two instruction cycles are required. One instruction cycle is
equal to 4 system clock cycles, therefore in the case of an 8MHz system oscillator, most instructions
would be implemented within 0.5μs and branch or call instructions would be implemented within
1μs. Although instructions which require one more cycle to implement are generally limited to
the JMP, CALL, RET, RETI and table read instructions, it is important to realize that any other
instructions which involve manipulation of the Program Counter Low register or PCL will also take
one more cycle to implement. As instructions which change the contents of the PCL will imply a
direct jump to that new address, one more cycle will be required. Examples of such instructions
would be "CLR PCL" or "MOV PCL, A". For the case of skip instructions, it must be noted that if
the result of the comparison involves a skip operation then this will also take one more cycle, if no
skip is involved then only one cycle is required.
Moving and Transferring Data
The transfer of data within the microcontroller program is one of the most frequently used
operations. Making use of three kinds of MOV instructions, data can be transferred from registers to
the Accumulator and vice-versa as well as being able to move specific immediate data directly into
the Accumulator. One of the most important data transfer applications is to receive data from the
input ports and transfer data to the output ports.
Arithmetic Operations
The ability to perform certain arithmetic operations and data manipulation is a necessary feature of
most microcontroller applications. Within the Holtek microcontroller instruction set are a range of
add and subtract instruction mnemonics to enable the necessary arithmetic to be carried out. Care
must be taken to ensure correct handling of carry and borrow data when results exceed 255 for
addition and less than 0 for subtraction. The increment and decrement instructions INC, INCA, DEC
and DECA provide a simple means of increasing or decreasing by a value of one of the values in the
destination specified.
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Logical and Rotate Operation
The standard logical operations such as AND, OR, XOR and CPL all have their own instruction
within the Holtek microcontroller instruction set. As with the case of most instructions involving
data manipulation, data must pass through the Accumulator which may involve additional
programming steps. In all logical data operations, the zero flag may be set if the result of the
operation is zero. Another form of logical data manipulation comes from the rotate instructions such
as RR, RL, RRC and RLC which provide a simple means of rotating one Bit right or left. Different
rotate instructions exist depending on program requirements. Rotate instructions are useful for serial
port programming applications where data can be rotated from an internal register into the Carry
Bit from where it can be examined and the necessary serial Bit set high or low. Another application
which rotate data operations are used is to implement multiplication and division calculations.
Branches and Control Transfer
Program branching takes the form of either jumps to specified locations using the JMP instruction
or to a subroutine using the CALL instruction. They differ in the sense that in the case of a
subroutine call, the program must return to the instruction immediately when the subroutine has
been carried out. This is done by placing a return instruction "RET" in the subroutine which will
cause the program to jump back to the address right after the CALL instruction. In the case of a JMP
instruction, the program simply jumps to the desired location. There is no requirement to jump back
to the original jumping off point as in the case of the CALL instruction. One special and extremely
useful set of branch instructions are the conditional branches. Here a decision is first made regarding
the condition of a certain data memory or individual Bits. Depending upon the conditions, the
program will continue with the next instruction or skip over it and jump to the following instruction.
These instructions are the key to decision making and branching within the program perhaps
determined by the condition of certain input switches or by the condition of internal data Bits.
Bit Operations
The ability to provide single Bit operations on Data Memory is an extremely flexible feature of all
Holtek microcontrollers. This feature is especially useful for output port Bit programming where
individual Bits or port pins can be directly set high or low using either the "SET [m].i" or "CLR [m].
i" instructions respectively. The feature removes the need for programmers to first read the 8-Bit
output port, manipulate the input data to ensure that other Bits are not changed and then output the
port with the correct new data. This read-modify-write process is taken care of automatically when
these Bit operation instructions are used.
Table Read Operations
Data storage is normally implemented by using registers. However, when working with large
amounts of fixed data, the volume involved often makes it inconvenient to store the fixed data in
the Data Memory. To overcome this problem, Holtek microcontrollers allow an area of Program
Memory to be set as a table where data can be directly stored. A set of easy to use instructions
provides the means by which this fixed data can be referenced and retrieved from the Program
Memory.
Other Operations
In addition to the above functional instructions, a range of other instructions also exist such as
the "HALT" instruction for Power-down operations and instructions to control the operation of
the Watchdog Timer for reliable program operations under extreme electric or electromagnetic
environments. For their relevant operations, refer to the functional related sections.
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Instruction Set Summary
The instructions related to the data memory access in the following table can be used when the
desired data memory is located in Data Memory sector 0.
Table Conventions
x: Bits immediate data
m: Data Memory address
A: Accumulator
i: 0~7 number of bits
addr: Program memory address
Mnemonic
Description
Cycles
Flag Affected
1
1Note
1
1
1Note
1
1
1Note
1
1
1Note
1Note
Z, C, AC, OV, SC
Z, C, AC, OV, SC
Z, C, AC, OV, SC
Z, C, AC, OV, SC
Z, C, AC, OV, SC
Z, C, AC, OV, SC, CZ
Z, C, AC, OV, SC, CZ
Z, C, AC, OV, SC, CZ
Z, C, AC, OV, SC, CZ
Z, C, AC, OV, SC, CZ
Z, C, AC, OV, SC, CZ
C
1
1
1
1Note
1Note
1Note
1
1
1
1Note
1
Z
Z
Z
Z
Z
Z
Z
Z
Z
Z
Z
Increment Data Memory with result in ACC
Increment Data Memory
Decrement Data Memory with result in ACC
Decrement Data Memory
1
1Note
1
1Note
Z
Z
Z
Z
Rotate Data Memory right with result in ACC
Rotate Data Memory right
Rotate Data Memory right through Carry with result in ACC
Rotate Data Memory right through Carry
Rotate Data Memory left with result in ACC
Rotate Data Memory left
Rotate Data Memory left through Carry with result in ACC
Rotate Data Memory left through Carry
1
1Note
1
1Note
1
1Note
1
1Note
None
None
C
C
None
None
C
C
Arithmetic
Add Data Memory to ACC
ADD A,[m]
ADDM A,[m]
Add ACC to Data Memory
ADD A,x
Add immediate data to ACC
ADC A,[m]
Add Data Memory to ACC with Carry
ADCM A,[m]
Add ACC to Data memory with Carry
SUB A,x
Subtract immediate data from the ACC
SUB A,[m]
Subtract Data Memory from ACC
SUBM A,[m]
Subtract Data Memory from ACC with result in Data Memory
SBC A,x
Subtract immediate data from ACC with Carry
SBC A,[m]
Subtract Data Memory from ACC with Carry
SBCM A,[m]
Subtract Data Memory from ACC with Carry, result in Data Memory
DAA [m]
Decimal adjust ACC for Addition with result in Data Memory
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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Mnemonic
Description
Cycles Flag Affected
Data Move
MOV A,[m]
MOV [m],A
MOV A,x
Move Data Memory to ACC
Move ACC to Data Memory
Move immediate data to ACC
1
1Note
1
None
None
None
Clear bit of Data Memory
Set bit of Data Memory
1Note
1Note
None
None
2
1Note
1Note
1Note
1Note
1Note
1Note
1Note
1Note
1Note
2
2
2
2
None
None
None
None
None
None
None
None
None
None
None
None
None
None
2Note
2Note
2Note
None
None
None
2Note
None
1
1Note
1Note
1
1Note
1
1
None
None
None
TO, PDF
None
None
TO, PDF
Bit Operation
CLR [m].i
SET [m].i
Branch Operation
JMP addr
SZ [m]
SZA [m]
SZ [m].i
SNZ [m]
SNZ [m].i
SIZ [m]
SDZ [m]
SIZA [m]
SDZA [m]
CALL addr
RET
RET A,x
RETI
Jump unconditionally
Skip if Data Memory is zero
Skip if Data Memory is zero with data movement to ACC
Skip if bit i of Data Memory is zero
Skip if Data Memory is not zero
Skip if bit i of Data Memory is not zero
Skip if increment Data Memory is zero
Skip if decrement Data Memory is zero
Skip if increment Data Memory is zero with result in ACC
Skip if decrement Data Memory is zero with result in ACC
Subroutine call
Return from subroutine
Return from subroutine and load immediate data to ACC
Return from interrupt
Table Read Operation
TABRD [m] Read table (specific page) to TBLH and Data Memory
TABRDL [m] Read table (last page) to TBLH and Data Memory
ITABRD [m] Increment table pointer TBLP first and Read table to TBLH and Data Memory
Increment table pointer TBLP first and Read table (last page) to TBLH and
ITABRDL [m]
Data Memory
Miscellaneous
NOP
CLR [m]
SET [m]
CLR WDT
SWAP [m]
SWAPA [m]
HALT
No operation
Clear Data Memory
Set Data Memory
Clear Watchdog Timer
Swap nibbles of Data Memory
Swap nibbles of Data Memory with result in ACC
Enter power down mode
Note: 1. For skip instructions, if the result of the comparison involves a skip then up to three cycles are required, if
no skip takes place only one cycle is required.
2. Any instruction which changes the contents of the PCL will also require 2 cycles for execution.
3. For the "CLR WDT" instruction the TO and PDF flags may be affected by the execution status. The TO
and PDF flags are cleared after the "CLR WDT" instructions is executed. Otherwise the TO and PDF
flags remain unchanged.
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Extended Instruction Set
The extended instructions are used to support the full range address access for the data memory.
When the accessed data memory is located in any data memory sections except sector 0, the
extended instruction can be used to access the data memory instead of using the indirect addressing
access to improve the CPU firmware performance.
Mnemonic
Description
Cycles
Flag Affected
2
2Note
2
2Note
2
2Note
2
2Note
2Note
Z, C, AC, OV, SC
Z, C, AC, OV, SC
Z, C, AC, OV, SC
Z, C, AC, OV, SC
Z, C, AC, OV, SC, CZ
Z, C, AC, OV, SC, CZ
Z, C, AC, OV, SC, CZ
Z, C, AC, OV, SC, CZ
C
2
2
2
2Note
2Note
2Note
2Note
2
Z
Z
Z
Z
Z
Z
Z
Z
Increment Data Memory with result in ACC
Increment Data Memory
Decrement Data Memory with result in ACC
Decrement Data Memory
2
2Note
2
2Note
Z
Z
Z
Z
Rotate Data Memory right with result in ACC
Rotate Data Memory right
Rotate Data Memory right through Carry with result in ACC
Rotate Data Memory right through Carry
Rotate Data Memory left with result in ACC
Rotate Data Memory left
Rotate Data Memory left through Carry with result in ACC
Rotate Data Memory left through Carry
2
2Note
2
2Note
2
2Note
2
2Note
None
None
C
C
None
None
C
C
Move Data Memory to ACC
Move ACC to Data Memory
2
2Note
None
None
Clear bit of Data Memory
Set bit of Data Memory
2Note
2Note
None
None
Arithmetic
Add Data Memory to ACC
LADD A,[m]
LADDM A,[m] Add ACC to Data Memory
LADC A,[m]
Add Data Memory to ACC with Carry
LADCM A,[m] Add ACC to Data memory with Carry
LSUB A,[m]
Subtract Data Memory from ACC
LSUBM A,[m] Subtract Data Memory from ACC with result in Data Memory
LSBC A,[m]
Subtract Data Memory from ACC with Carry
LSBCM A,[m] Subtract Data Memory from ACC with Carry, result in Data Memory
LDAA [m]
Decimal adjust ACC for Addition with result in Data Memory
Logic Operation
LAND A,[m]
Logical AND Data Memory to ACC
LOR A,[m]
Logical OR Data Memory to ACC
LXOR A,[m]
Logical XOR Data Memory to ACC
LANDM A,[m] Logical AND ACC to Data Memory
LORM A,[m]
Logical OR ACC to Data Memory
LXORM A,[m] Logical XOR ACC to Data Memory
LCPL [m]
Complement Data Memory
LCPLA [m]
Complement Data Memory with result in ACC
Increment & Decrement
LINCA [m]
LINC [m]
LDECA [m]
LDEC [m]
Rotate
LRRA [m]
LRR [m]
LRRCA [m]
LRRC [m]
LRLA [m]
LRL [m]
LRLCA [m]
LRLC [m]
Data Move
LMOV A,[m]
LMOV [m],A
Bit Operation
LCLR [m].i
LSET [m].i
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Mnemonic
Description
Cycles Flag Affected
Branch
LSZ [m]
LSZA [m]
LSNZ [m]
LSZ [m].i
LSNZ [m].i
LSIZ [m]
LSDZ [m]
LSIZA [m]
LSDZA [m]
Skip if Data Memory is zero
Skip if Data Memory is zero with data movement to ACC
Skip if Data Memory is not zero
Skip if bit i of Data Memory is zero
Skip if bit i of Data Memory is not zero
Skip if increment Data Memory is zero
Skip if decrement Data Memory is zero
Skip if increment Data Memory is zero with result in ACC
Skip if decrement Data Memory is zero with result in ACC
2Note
2Note
2Note
2Note
2Note
2Note
2Note
2Note
2Note
None
None
None
None
None
None
None
None
None
3Note
3Note
3Note
None
None
None
3Note
None
2Note
2Note
2Note
2
None
None
None
None
Table Read
LTABRD [m] Read table to TBLH and Data Memory
LTABRDL [m] Read table (last page) to TBLH and Data Memory
LITABRD [m] Increment table pointer TBLP first and Read table to TBLH and Data Memory
Increment table pointer TBLP first and Read table (last page) to TBLH and
LITABRDL [m]
Data Memory
Miscellaneous
LCLR [m]
LSET [m]
LSWAP [m]
LSWAPA [m]
Clear Data Memory
Set Data Memory
Swap nibbles of Data Memory
Swap nibbles of Data Memory with result in ACC
Note: 1. For these extended skip instructions, if the result of the comparison involves a skip then up to four cycles
are required, if no skip takes place two cycles is required.
2. Any extended instruction which changes the contents of the PCL register will also require three cycles for
execution.
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Instruction Definition
ADC A,[m]
Description
Operation
Affected flag(s)
ADCM A,[m]
Description
Operation
Affected flag(s)
ADD A,[m]
Description
Add Data Memory to ACC with Carry
The contents of the specified Data Memory, Accumulator and the carry flag are added.
The result is stored in the Accumulator.
ACC ← ACC + [m] + C
OV, Z, AC, C, SC
Add ACC to Data Memory with Carry
The contents of the specified Data Memory, Accumulator and the carry flag are added.
The result is stored in the specified Data Memory.
[m] ← ACC + [m] + C
OV, Z, AC, C, SC
Add Data Memory to ACC
The contents of the specified Data Memory and the Accumulator are added.
The result is stored in the Accumulator.
Operation
Affected flag(s)
ACC ← ACC + [m]
OV, Z, AC, C, SC
ADD A,x
Description
Add immediate data to ACC
The contents of the Accumulator and the specified immediate data are added.
The result is stored in the Accumulator.
ACC ← ACC + x
OV, Z, AC, C, SC
Operation
Affected flag(s)
ADDM A,[m]
Description
Operation
Affected flag(s)
AND A,[m]
Description
Operation
Affected flag(s)
AND A,x
Description
Operation
Affected flag(s)
ANDM A,[m]
Description
Operation
Affected flag(s)
Rev. 1.20
Add ACC to Data Memory
The contents of the specified Data Memory and the Accumulator are added.
The result is stored in the specified Data Memory.
[m] ← ACC + [m]
OV, Z, AC, C, SC
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
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
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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Touch A/D Flash MCU with OCVP
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
Clear Watchdog Timer
The TO, PDF flags and the WDT are all cleared.
WDT cleared
TO ← 0
PDF ← 0
TO, PDF
CALL addr
Description
Operation
Affected flag(s)
CPL [m]
Description
Operation
Affected flag(s)
CPLA [m]
Description
Operation
Affected flag(s)
DAA [m]
Description
Operation
Affected flag(s)
Rev. 1.20
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
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
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
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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
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
Operation
Affected flag(s)
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
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
HALT
Description
Operation
Operation
Affected flag(s)
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
JMP addr
Description
Rev. 1.20
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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
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
Operation
Affected flag(s)
OR A,x
Description
Operation
Affected flag(s)
ORM A,[m]
Description
Operation
Affected flag(s)
RET
Description
Operation
Affected flag(s)
RET A,x
Description
Operation
Affected flag(s)
RETI
Description
Operation
Affected flag(s)
RL [m]
Description
Operation
Affected flag(s)
Rev. 1.20
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
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
Return from subroutine
The Program Counter is restored from the stack. Program execution continues at the restored
address.
Program Counter ← Stack
None
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
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
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
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RLA [m]
Description
Operation
Affected flag(s)
RLC [m]
Description
Operation
Affected flag(s)
RLCA [m]
Description
Operation
Affected flag(s)
RR [m]
Description
Operation
Affected flag(s)
RRA [m]
Description
Operation
Affected flag(s)
RRC [m]
Description
Operation
Affected flag(s)
Rev. 1.20
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
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
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
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
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
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
207
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RRCA [m]
Description
Operation
Affected flag(s)
SBC A,[m]
Description
Operation
Affected flag(s)
SBC A, x
Description
Operation
Affected flag(s)
SBCM A,[m]
Description
Operation
Affected flag(s)
SDZ [m]
Description
Operation
Affected flag(s)
SDZA [m]
Description
Operation
Affected flag(s)
Rev. 1.20
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
Subtract Data Memory from ACC with Carry
The contents of the specified Data Memory and the complement of the carry flag are
subtracted from the Accumulator. The result is stored in the Accumulator. Note that if the
result of subtraction is negative, the C flag will be cleared to 0, otherwise if the result is
positive or zero, the C flag will be set to 1.
ACC ← ACC − [m] − C
OV, Z, AC, C, SC, CZ
Subtract immediate data from ACC with Carry
The immediate data and the complement of the carry flag are subtracted from the
Accumulator. The result is stored in the Accumulator. Note that if the result of subtraction is
negative, the C flag will be cleared to 0, otherwise if the result is positive or zero, the C flag
will be set to 1.
ACC ← ACC - [m] - C
OV, Z, AC, C, SC, CZ
Subtract Data Memory from ACC with Carry and result in Data Memory
The contents of the specified Data Memory and the complement of the carry flag are
subtracted from the Accumulator. The result is stored in the Data Memory. Note that if the
result of subtraction is negative, the C flag will be cleared to 0, otherwise if the result is
positive or zero, the C flag will be set to 1.
[m] ← ACC − [m] − C
OV, Z, AC, C, SC, CZ
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
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
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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
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
Operation
Affected flag(s)
SIZA [m]
Description
Operation
Affected flag(s)
SNZ [m].i
Description
Operation
Affected flag(s)
SNZ [m]
Description
Operation
Affected flag(s)
SUB A,[m]
Description
Operation
Affected flag(s)
Rev. 1.20
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
Skip if Data Memory is not 0
If the specified Data Memory is not 0, the following instruction is skipped. As this requires the
insertion of a dummy instruction while the next instruction is fetched, it is a two cycle
instruction. If the result is 0 the program proceeds with the following instruction.
Skip if [m].i ≠ 0
None
Skip if Data Memory is not 0
If the specified Data Memory is not 0, the following instruction is skipped. As this requires the
insertion of a dummy instruction while the next instruction is fetched, it is a two cycle
instruction. If the result is 0 the program proceeds with the following instruction.
Skip if [m]≠ 0
None
Subtract Data Memory from ACC
The specified Data Memory is subtracted from the contents of the Accumulator. The result is
stored in the Accumulator. Note that if the result of subtraction is negative, the C flag will be
cleared to 0, otherwise if the result is positive or zero, the C flag will be set to 1.
ACC ← ACC − [m]
OV, Z, AC, C, SC, CZ
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SUBM A,[m]
Description
Operation
Affected flag(s)
Subtract Data Memory from ACC with result in Data Memory
The specified Data Memory is subtracted from the contents of the Accumulator. The result is
stored in the Data Memory. Note that if the result of subtraction is negative, the C flag will be
cleared to 0, otherwise if the result is positive or zero, the C flag will be set to 1.
[m] ← ACC − [m]
OV, Z, AC, C, SC, CZ
Operation
Affected flag(s)
Subtract immediate data from ACC
The immediate data specified by the code is subtracted from the contents of the Accumulator.
The result is stored in the Accumulator. Note that if the result of subtraction is negative, the C
flag will be cleared to 0, otherwise if the result is positive or zero, the C flag will be set to 1.
ACC ← ACC − x
OV, Z, AC, C, SC, CZ
SWAP [m]
Description
Operation
Affected flag(s)
Swap nibbles of Data Memory
The low-order and high-order nibbles of the specified Data Memory are interchanged.
[m].3~[m].0 ↔ [m].7~[m].4
None
SWAPA [m]
Description
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
SUB A,x
Description
Operation
Affected flag(s)
SZ [m]
Description
Operation
Affected flag(s)
SZA [m]
Description
Operation
Affected flag(s)
SZ [m].i
Description
Operation
Affected flag(s)
Rev. 1.20
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
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
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
210
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Touch A/D Flash MCU with OCVP
TABRD [m]
Description
Operation
Affected flag(s)
TABRDL [m]
Description
Operation
Affected flag(s)
ITABRD [m]
Description
Operation
Affected flag(s)
ITABRDL [m]
Description
Operation
Affected flag(s)
XOR A,[m]
Description
Operation
Affected flag(s)
XORM A,[m]
Description
Operation
Affected flag(s)
XOR A,x
Description
Operation
Affected flag(s)
Rev. 1.20
Read table (specific page) to TBLH and Data Memory
The low byte of the program code (specific page) addressed by the table pointer pair
(TBLP and TBHP) 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
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
Increment table pointer low byte first and read table to TBLH and Data Memory
Increment table pointer low byte, TBLP, first and then the program code addressed by the
table pointer (TBHP and TBLP) is moved to the specified Data Memory and the high byte
moved to TBLH.
[m] ← program code (low byte)
TBLH ← program code (high byte)
None
Increment table pointer low byte first and read table (last page) to TBLH and Data Memory
Increment table pointer low byte, TBLP, first and then the low byte of the program code
(last page) addressed by the table pointer (TBLP) is moved to the specified Data Memory and
the high byte moved to TBLH.
[m] ← program code (low byte)
TBLH ← program code (high byte)
None
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
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
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
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Touch A/D Flash MCU with OCVP
Extended Instruction Definition
The extended instructions are used to directly access the data stored in any data memory sections.
LADC A,[m]
Description
Operation
Affected flag(s)
LADCM A,[m]
Description
Operation
Affected flag(s)
LADD A,[m]
Description
Add Data Memory to ACC with Carry
The contents of the specified Data Memory, Accumulator and the carry flag are added.
The result is stored in the Accumulator.
ACC ← ACC + [m] + C
OV, Z, AC, C, SC
Add ACC to Data Memory with Carry
The contents of the specified Data Memory, Accumulator and the carry flag are added.
The result is stored in the specified Data Memory.
[m] ← ACC + [m] + C
OV, Z, AC, C, SC
Add Data Memory to ACC
The contents of the specified Data Memory and the Accumulator are added.
The result is stored in the Accumulator.
Operation
Affected flag(s)
ACC ← ACC + [m]
OV, Z, AC, C, SC
LADDM A,[m]
Description
Add ACC to Data Memory
The contents of the specified Data Memory and the Accumulator are added.
The result is stored in the specified Data Memory.
[m] ← ACC + [m]
OV, Z, AC, C, SC
Operation
Affected flag(s)
LAND A,[m]
Description
Operation
Affected flag(s)
Logical AND Data Memory to ACC
Data in the Accumulator and the specified Data Memory perform a bitwise logical AND
operation. The result is stored in the Accumulator.
ACC ← ACC ″AND″ [m]
Z
Operation
Affected flag(s)
Logical AND ACC to Data Memory
Data in the specified Data Memory and the Accumulator perform a bitwise logical AND
operation. The result is stored in the Data Memory.
[m] ← ACC ″AND″ [m]
Z
LCLR [m]
Description
Operation
Affected flag(s)
Clear Data Memory
Each bit of the specified Data Memory is cleared to 0.
[m] ← 00H
None
LCLR [m].i
Description
Operation
Affected flag(s)
Clear bit of Data Memory
Bit i of the specified Data Memory is cleared to 0.
[m].i ← 0
None
LANDM A,[m]
Description
Rev. 1.20
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Touch A/D Flash MCU with OCVP
LCPL [m]
Description
Operation
Affected flag(s)
LCPLA [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
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
Affected flag(s)
Decimal-Adjust ACC for addition with result in Data Memory
Convert the contents of the Accumulator value to a BCD (Binary Coded Decimal) value
resulting from the previous addition of two BCD variables. If the low nibble is greater than 9
or if AC flag is set, then a value of 6 will be added to the low nibble. Otherwise the low nibble
remains unchanged. If the high nibble is greater than 9 or if the C flag is set, then a value of 6
will be added to the high nibble. Essentially, the decimal conversion is performed by adding
00H, 06H, 60H or 66H depending on the Accumulator and flag conditions. Only the C flag
may be affected by this instruction which indicates that if the original BCD sum is greater than
100, it allows multiple precision decimal addition.
[m] ← ACC + 00H or
[m] ← ACC + 06H or
[m] ← ACC + 60H or
[m] ← ACC + 66H
C
LDEC [m]
Description
Operation
Affected flag(s)
Decrement Data Memory
Data in the specified Data Memory is decremented by 1.
[m] ← [m] − 1
Z
LDECA [m]
Description
Operation
Affected flag(s)
Decrement Data Memory with result in ACC
Data in the specified Data Memory is decremented by 1. The result is stored in the
Accumulator. The contents of the Data Memory remain unchanged.
ACC ← [m] − 1
Z
LINC [m]
Description
Operation
Affected flag(s)
Increment Data Memory
Data in the specified Data Memory is incremented by 1.
[m] ← [m] + 1
Z
LINCA [m]
Description
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
LDAA [m]
Description
Operation
Operation
Affected flag(s)
Rev. 1.20
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Touch A/D Flash MCU with OCVP
LMOV A,[m]
Description
Operation
Affected flag(s)
Move Data Memory to ACC
The contents of the specified Data Memory are copied to the Accumulator.
ACC ← [m]
None
LMOV [m],A
Description
Operation
Affected flag(s)
Move ACC to Data Memory
The contents of the Accumulator are copied to the specified Data Memory.
[m] ← ACC
None
LOR A,[m]
Description
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
Operation
Affected flag(s)
LORM A,[m]
Description
Operation
Affected flag(s)
LRL [m]
Description
Operation
Affected flag(s)
LRLA [m]
Description
Operation
Affected flag(s)
LRLC [m]
Description
Operation
Affected flag(s)
LRLCA [m]
Description
Operation
Affected flag(s)
Rev. 1.20
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
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
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
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
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
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LRR [m]
Description
Operation
Affected flag(s)
LRRA [m]
Description
Operation
Affected flag(s)
LRRC [m]
Description
Operation
Affected flag(s)
LRRCA [m]
Description
Operation
Affected flag(s)
LSBC A,[m]
Description
Operation
Affected flag(s)
LSBCM A,[m]
Description
Operation
Affected flag(s)
Rev. 1.20
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
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
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
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
Subtract Data Memory from ACC with Carry
The contents of the specified Data Memory and the complement of the carry flag are
subtracted from the Accumulator. The result is stored in the Accumulator. Note that if the
result of subtraction is negative, the C flag will be cleared to 0, otherwise if the result is
positive or zero, the C flag will be set to 1.
ACC ← ACC − [m] − C
OV, Z, AC, C, SC, CZ
Subtract Data Memory from ACC with Carry and result in Data Memory
The contents of the specified Data Memory and the complement of the carry flag are
subtracted from the Accumulator. The result is stored in the Data Memory. Note that if the
result of subtraction is negative, the C flag will be cleared to 0, otherwise if the result is
positive or zero, the C flag will be set to 1.
[m] ← ACC − [m] − C
OV, Z, AC, C, SC, CZ
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LSDZ [m]
Description
Operation
Affected flag(s)
Skip if decrement Data Memory is 0
The contents of the specified Data Memory are first decremented by 1. If the result is 0 the
following instruction is skipped. As this requires the insertion of a dummy instruction while
the next instruction is fetched, it is a two cycle instruction. If the result is not 0 the program
proceeds with the following instruction.
[m] ← [m] − 1
Skip if [m]=0
None
Affected flag(s)
Skip if decrement Data Memory is zero with result in ACC
The contents of the specified Data Memory are first decremented by 1. If the result is 0, the
following instruction is skipped. The result is stored in the Accumulator but the specified
Data Memory contents remain unchanged. As this requires the insertion of a dummy
instruction while the next instruction is fetched, it is a two cycle instruction. If the result is not 0,
the program proceeds with the following instruction.
ACC ← [m] − 1
Skip if ACC=0
None
LSET [m]
Description
Operation
Affected flag(s)
Set Data Memory
Each bit of the specified Data Memory is set to 1.
[m] ← FFH
None
LSET [m].i
Description
Operation
Affected flag(s)
Set bit of Data Memory
Bit i of the specified Data Memory is set to 1.
[m].i ← 1
None
LSIZ [m]
Description
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
LSDZA [m]
Description
Operation
Operation
Affected flag(s)
LSIZA [m]
Description
Operation
Affected flag(s)
LSNZ [m].i
Description
Operation
Affected flag(s)
Rev. 1.20
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
Skip if Data Memory is not 0
If the specified Data Memory is not 0, the following instruction is skipped. As this requires the
insertion of a dummy instruction while the next instruction is fetched, it is a two cycle
instruction. If the result is 0 the program proceeds with the following instruction.
Skip if [m].i ≠ 0
None
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LSNZ [m]
Description
Operation
Affected flag(s)
LSUB A,[m]
Description
Operation
Affected flag(s)
Skip if Data Memory is not 0
If the content of the specified Data Memory is not 0, the following instruction is skipped. As
this requires the insertion of a dummy instruction while the next instruction is fetched, it is a
two cycle instruction. If the result is 0 the program proceeds with the following instruction.
Skip if [m] ≠ 0
None
Subtract Data Memory from ACC
The specified Data Memory is subtracted from the contents of the Accumulator. The result is
stored in the Accumulator. Note that if the result of subtraction is negative, the C flag will be
cleared to 0, otherwise if the result is positive or zero, the C flag will be set to 1.
ACC ← ACC − [m]
OV, Z, AC, C, SC, CZ
Operation
Affected flag(s)
Subtract Data Memory from ACC with result in Data Memory
The specified Data Memory is subtracted from the contents of the Accumulator. The result is
stored in the Data Memory. Note that if the result of subtraction is negative, the C flag will be
cleared to 0, otherwise if the result is positive or zero, the C flag will be set to 1.
[m] ← ACC − [m]
OV, Z, AC, C, SC, CZ
LSWAP [m]
Description
Operation
Affected flag(s)
Swap nibbles of Data Memory
The low-order and high-order nibbles of the specified Data Memory are interchanged.
[m].3~[m].0 ↔ [m].7~[m].4
None
LSWAPA [m]
Description
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
LSUBM A,[m]
Description
Operation
Affected flag(s)
LSZ [m]
Description
Operation
Affected flag(s)
LSZA [m]
Description
Operation
Affected flag(s)
Rev. 1.20
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
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
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LSZ [m].i
Description
Operation
Affected flag(s)
LTABRD [m]
Description
Operation
Affected flag(s)
LTABRDL [m]
Description
Operation
Affected flag(s)
LITABRD [m]
Description
Operation
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
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
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
Increment table pointer low byte first and read table to TBLH and Data Memory
Increment table pointer low byte, TBLP, first and then the program code addressed by the
table pointer (TBHP and TBLP) is moved to the specified Data Memory and the high byte
moved to TBLH.
[m] ← program code (low byte)
TBLH ← program code (high byte)
Affected flag(s)
None
LITABRDL [m]
Description
Increment table pointer low byte first and read table (last page) to TBLH and Data Memory
Increment table pointer low byte, TBLP, first and then the low byte of the program code
(last page) addressed by the table pointer (TBLP) is moved to the specified Data Memory and
the high byte moved to TBLH.
[m] ← program code (low byte)
TBLH ← program code (high byte)
None
Operation
Affected flag(s)
LXOR A,[m]
Description
Operation
Affected flag(s)
LXORM A,[m]
Description
Operation
Affected flag(s)
Rev. 1.20
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
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
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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.
• Further Package Information (include Outline Dimensions, Product Tape and Reel Specifications)
• Packing Meterials Information
• Carton information
Rev. 1.20
219
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20-pin NSOP (150mil) Outline Dimensions
Symbol
A
Dimensions in inch
Min.
Nom.
Max.
0.228
0.236
0.244
B
0.146
0.154
0.161
C
0.009
—
0.012
C’
0.382
0.390
0.398
D
—
—
0.069
E
—
0.032 BSC
—
F
0.002
—
0.009
G
0.020
—
0.031
H
0.008
—
0.010
α
0°
—
8°
Symbol
Rev. 1.20
Dimensions in mm
Min.
Nom.
Max.
A
5.80
6.00
6.20
B
3.70
3.90
4.10
C
0.23
—
0.30
C’
9.70
9.90
10.10
1.75
D
—
—
E
—
0.80 BSC
—
F
0.05
—
0.23
G
0.50
—
0.80
H
0.21
—
0.25
α
0°
—
8°
220
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24-pin SOP (300mil) Outline Dimensions
Symbol
Dimensions in inch
Min.
Nom.
Max.
A
—
0.406 BSC
—
B
—
0.295 BSC
—
C
0.012
—
0.020
C’
—
0.606 BSC
—
D
—
—
0.104
E
—
0.050 BSC
—
F
0.004
—
0.012
G
0.016
—
0.050
H
0.008
—
0.013
α
0°
—
8°
Symbol
Rev. 1.20
Dimensions in mm
Min.
Nom.
A
—
10.30 BSC
Max.
—
B
—
7.5 BSC
—
0.51
C
0.31
—
C’
—
15.4 BSC
—
D
—
—
2.65
E
—
1.27 BSC
—
F
0.10
—
0.30
G
0.40
—
1.27
H
0.20
—
0.33
α
0°
—
8°
221
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28-pin SOP (300mil) Outline Dimensions
Symbol
Dimensions in inch
Min.
Nom.
Max.
A
—
0.406 BSC
—
B
—
0.295 BSC
—
C
0.012
—
0.020
C’
—
0.705 BSC
—
D
—
—
0.104
E
—
0.050 BSC
—
F
0.004
—
0.012
G
0.016
—
0.050
H
0.008
—
0.013
α
0°
—
8°
Symbol
Rev. 1.20
Dimensions in mm
Min.
Nom.
Max.
A
—
10.30 BSC
—
B
—
7.5 BSC
—
0.51
C
0.31
—
C’
—
17.9 BSC
—
D
—
—
2.65
E
—
1.27 BSC
—
F
0.10
—
0.30
G
0.40
—
1.27
H
0.20
—
0.33
α
0°
—
8°
222
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44-pin LQFP (10mm×10mm) (FP2.0mm) Outline Dimensions
Symbol
Dimensions in inch
Min.
Nom.
Max.
A
—
0.472 BSC
—
B
—
0.394 BSC
—
C
—
0.472 BSC
—
D
—
0.394 BSC
—
E
—
0.032 BSC
—
F
0.012
0.015
0.018
G
0.053
0.055
0.057
H
—
—
0.063
I
0.002
—
0.006
J
0.018
0.024
0.030
K
0.004
—
0.008
α
0°
—
7°
Symbol
Rev. 1.20
Dimensions in mm
Min.
Nom.
Max.
A
—
12.00 BSC
—
B
—
10.00 BSC
—
C
—
12.00 BSC
—
D
—
10.00 BSC
—
E
—
0.80 BSC
—
F
0.30
0.37
0.45
G
1.35
1.40
1.45
H
—
—
1.60
I
0.05
—
0.15
J
0.45
0.60
0.75
K
0.09
—
0.20
α
0°
—
7°
223
December 05, 2016
BS87B12A-3/BS87C16A-3/BS87D20A-3
Touch A/D Flash MCU with OCVP
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/en/home.
Rev. 1.20
224
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