Holtek HT85F2270 User manual

Standard 8051 8-Bit Flash MCU
HT85F2260
HT85F2270
HT85F2280
Revision: V1.00 Date: January 15, 2015January 15, 2015

Rev. 1.00 2 of 225 January 15, 2015
Standard 8051 8-Bit Flash MCU
HT85F2260/HT85F2270/HT85F2280
Table of Contents
Table of Contents
1 Features................................................................................................................. 14
CPU Features.................................................................................................................... 14
Peripheral Features........................................................................................................... 15
2 General Description ............................................................................................. 16
3 Selection Table...................................................................................................... 17
4 Block Diagram....................................................................................................... 18
5 Pin Assignment..................................................................................................... 19
6 Pin Descriptions ................................................................................................... 20
7 Absolute Maximum Ratings................................................................................. 23
8 D.C. Characteristics.............................................................................................. 23
9 A.C. Characteristics.............................................................................................. 25
10 ADC Electrical Characteristics ......................................................................... 26
11 DAC Electrical Characteristics .......................................................................... 26
12 Comparator Electrical Characteristics ............................................................. 27
13 Power on Reset Electrical Characteristics....................................................... 28
14 System Architecture........................................................................................... 28
15 Program Counter ................................................................................................ 29
16 Stack .................................................................................................................... 29
17 Arithmetic and Logic Unit – ALU....................................................................... 30
18 Flash Program Memory...................................................................................... 31
Structure............................................................................................................................ 31
Special Vectors.................................................................................................................. 31
In-Circuit Programming – ICP ........................................................................................... 32
On-Chip Debug Support – OCDS ..................................................................................... 32
In-Application Programming – IAP .................................................................................... 33
Flash Program Memory Resisters..................................................................................... 33
Flash Memory Read/Write Operations.............................................................................. 37
Unlocking the Flash Memory........................................................................................................ 37
Page Erase Operation.................................................................................................................. 38
Byte Read Operation.................................................................................................................... 39
Byte Write Operation .................................................................................................................... 40

Rev. 1.00 3 of 225 January 15, 2015
Standard 8051 8-Bit Flash MCU
HT85F2260/HT85F2270/HT85F2280
Table of Contents Table of Contents
Program Memory Protection ............................................................................................. 42
Memory Protection Control Bytes................................................................................................. 42
19 RAM Data Memory .............................................................................................. 46
Structure............................................................................................................................ 46
Register Banks.................................................................................................................. 50
Bit Addressable Space ...................................................................................................... 50
Special Function Registers................................................................................................ 52
ACC Register – Accumulator........................................................................................................ 53
B Register .................................................................................................................................... 53
SP Register – Stack Pointer......................................................................................................... 53
DPL, DPH, DPL1, DPH1 Registers – Data Pointer Registers...................................................... 53
Data Pointer Select Registers ...................................................................................................... 54
Data Pointer Control Register....................................................................................................... 54
Program Status Word................................................................................................................... 56
20 Oscillators ........................................................................................................... 57
System Oscillator Overview .............................................................................................. 57
System Clock Conguration.............................................................................................. 57
External High Speed Crystal Oscillator – HXT ............................................................................. 57
Internal High Speed RC Oscillator – HIRC................................................................................... 58
External Low Speed Crystal Oscillator – LXT............................................................................... 58
Internal Low Speed RC Oscillator – LIRC .................................................................................... 59
21 Operating Modes and System Clocks .............................................................. 60
System Clocks Description................................................................................................ 60
Phase Locked Loop – PLL ................................................................................................ 64
Changing the PLL Frequency....................................................................................................... 64
Operation Modes............................................................................................................... 66
NORMAL Mode ............................................................................................................................ 66
IDLE Mode.................................................................................................................................... 66
Power-Down Mode....................................................................................................................... 66
Power Control Register ..................................................................................................... 67
Standby Current Considerations ....................................................................................... 67
Wake-up ............................................................................................................................ 68
22 Watchdog Timer.................................................................................................. 69
Watchdog Registers .......................................................................................................... 70
Watchdog Timer Clock Source.......................................................................................... 73
Watchdog Timer Operation ............................................................................................... 73

Rev. 1.00 4 of 225 January 15, 2015
Standard 8051 8-Bit Flash MCU
HT85F2260/HT85F2270/HT85F2280
Table of Contents
23 Low Voltage Detector – LVD .............................................................................. 75
LVD Register ..................................................................................................................... 75
LVD Operation................................................................................................................... 75
24 Reset and Initialisation....................................................................................... 76
Reset Overview................................................................................................................. 76
Reset Operations .............................................................................................................. 77
Reset Source Register – RSTSRC............................................................................................... 77
Power-on Reset............................................................................................................................ 78
RESET Pin Reset ......................................................................................................................... 79
Low Voltage Reset – LVR............................................................................................................. 80
Watchdog Reset .......................................................................................................................... 81
Comparator 0 Reset ..................................................................................................................... 82
Software Resets ........................................................................................................................... 83
SRST Register Software Reset.................................................................................................... 83
WDTCR Register Software Reset ................................................................................................ 84
LVRCR Register Software Reset.................................................................................................. 84
ROM Code Check Reset.............................................................................................................. 85
Reset Initial Conditions...................................................................................................... 85
25 Interrupts ............................................................................................................. 91
Interrupt Registers............................................................................................................. 91
Interrupt Operation .......................................................................................................... 103
Interrupt Priority............................................................................................................... 106
Priority Levels............................................................................................................................. 106
Priority Control Registers............................................................................................................ 108
External Interrupt..............................................................................................................111
Comparator Interrupt....................................................................................................... 112
A/D Converter Interrupt ................................................................................................... 113
Timer/Counter Interrupt ................................................................................................... 113
Time Base Interrupts ....................................................................................................... 113
I2C Interface Interrupt ...................................................................................................... 114
SPI Interface Interrupt ..................................................................................................... 115
UART Interface Interrupt ................................................................................................. 115
LVD Interrupt ................................................................................................................... 115
Interrupt Wake-up Function............................................................................................. 116
Programming Considerations.......................................................................................... 116

Rev. 1.00 5 of 225 January 15, 2015
Standard 8051 8-Bit Flash MCU
HT85F2260/HT85F2270/HT85F2280
Table of Contents Table of Contents
26 Input/Output Ports ............................................................................................ 117
Input/Output Port Overview............................................................................................. 117
Register Description........................................................................................................ 118
PnM0/PnM1 Registers – Port Mode Registers........................................................................... 120
P0WAKE Register – Port 0 Wake-up ......................................................................................... 122
SRCR Register – Slew Rate Control.......................................................................................... 122
I/O Pin Structures............................................................................................................ 123
Quasi-bidirectional I/O – All Ports............................................................................................... 123
Push-pull Output – Ports 0~3 Only............................................................................................. 124
Open-drain Output – Ports 0~3 Only.......................................................................................... 124
Input Only – Ports 0~3 Only ....................................................................................................... 124
Programming Considerations.......................................................................................... 125
27 Timer/Event Counters ...................................................................................... 126
Timer/Event Counter Summary....................................................................................... 126
28 Timer/Event Counters 0, 1, 3 ........................................................................... 127
Introduction...................................................................................................................... 127
Timer 0/Timer 1/Timer 3 Register Description................................................................. 128
Mode 0 – 13-bit Counter/Timer Mode Operation............................................................. 135
Mode 1 – 16-bit Counter/Timer Mode Operation............................................................. 135
Mode 2 – 8-bit Auto-reload Counter/Timer Mode Operation ........................................... 136
Mode 3 – Two 8-Bit Timers/Counters Mode Operation – Timer 0 Only........................... 137
29 Timer 2 with Additional 4-channel PCA .......................................................... 138
Introduction...................................................................................................................... 138
Timer 2 ............................................................................................................................ 140
Timer function............................................................................................................................. 140
Event Counter function............................................................................................................... 140
Gated Timer function .................................................................................................................. 140
Timer 2 with PCA............................................................................................................. 141
Timer 2 Register Description........................................................................................... 142
Capture Modes................................................................................................................ 145
Capture On Edge Mode.............................................................................................................. 145
Capture On Write Mode.............................................................................................................. 145
Compare Modes.............................................................................................................. 146
Compare Mode 0........................................................................................................................ 146
Compare Mode 1........................................................................................................................ 148
Reload Mode................................................................................................................... 150
Programmable Clock Output Mode................................................................................. 151

Rev. 1.00 6 of 225 January 15, 2015
Standard 8051 8-Bit Flash MCU
HT85F2260/HT85F2270/HT85F2280
Table of Contents
30 Analog to Digital Converter – ADC ................................................................. 152
A/D Overview .................................................................................................................. 152
A/D Converter Register Description ................................................................................ 153
A/D Converter Data Registers – ADRL, ADRH ............................................................... 153
A/D Converter Control Registers – ADCR0, ADCR1, ADCR2, ADPGA .......................... 153
A/D Operation.................................................................................................................. 157
A/D Converter Clock Source ........................................................................................... 158
A/D Input Pins ................................................................................................................. 158
Temperature Sensor........................................................................................................ 159
A/D Reference Voltage Source ....................................................................................... 159
Summary of A/D Conversion Steps................................................................................. 160
A/D Conversion Timing.................................................................................................... 161
Programming Considerations.......................................................................................... 162
A/D Transfer Function ..................................................................................................... 162
31 Digital to Analog Converter – DAC.................................................................. 163
DAC Register Description ............................................................................................... 163
DAC Operation................................................................................................................ 165
DAC Reference Voltage Source...................................................................................... 166
Programming Considerations.......................................................................................... 166
32 Voltage Reference Generator .......................................................................... 167
Voltage Reference Generator Operation......................................................................... 167
33 Comparators ..................................................................................................... 169
Comparator Operation..................................................................................................... 169
Comparator Registers ..................................................................................................... 170
Comparator Interrupt....................................................................................................... 175
Comparator Reset Function ............................................................................................ 175
Programming Considerations.......................................................................................... 175
34 I2C Serial Interface ............................................................................................ 176
I2C Interface Operation.................................................................................................... 176
I2C Registers ................................................................................................................... 177
I2C Bus Communication .................................................................................................. 181
I2C Bus Start Signal.................................................................................................................... 182
Slave Address............................................................................................................................. 182
I2C Bus Read/Write Signal.......................................................................................................... 182
I2C Bus Slave Address Acknowledge Signal .............................................................................. 182
I2C Bus Data and Acknowledge Signal....................................................................................... 183
I2C Status Codes ........................................................................................................................ 184

Rev. 1.00 7 of 225 January 15, 2015
Standard 8051 8-Bit Flash MCU
HT85F2260/HT85F2270/HT85F2280
Table of Contents Table of Contents
35 Serial Interface – SPI ........................................................................................ 189
SPI Interface Operation................................................................................................... 189
SPI Features............................................................................................................................... 190
SPI Registers .................................................................................................................. 191
SPI Communication......................................................................................................... 194
36 UART Serial Interfaces – UART0 and UART1................................................. 197
UART Overview............................................................................................................... 197
UART0 Features......................................................................................................................... 197
UART1 Features......................................................................................................................... 197
Basic UART Data Transfer Scheme ........................................................................................... 198
UART0 Operating Description......................................................................................... 199
UART0 External Pin Interfacing.................................................................................................. 199
UART0 Register Description ...................................................................................................... 200
UART0 Operating Modes ........................................................................................................... 204
UART0 Multiprocessor Communication .................................................................................... 208
UART0 Baud Rate Setup ........................................................................................................... 208
UART1 Operating Description......................................................................................... 209
UART1 External Pin Interfacing.................................................................................................. 209
UART1 Register Description ...................................................................................................... 210
UART1 Operating Modes ........................................................................................................... 213
UART1 Multiprocessor Communication ..................................................................................... 215
UART1 Baud Rate Setup ........................................................................................................... 215
37 Instruction Set................................................................................................... 216
Introduction...................................................................................................................... 216
Read-Modify-Write Instruction......................................................................................... 221
38 Package Information ........................................................................................ 222
48-pin LQFP (7mm×7mm) Outline Dimensions .............................................................. 223
64-pin LQFP (7mm × 7mm) Outline Dimensions ............................................................ 224

Rev. 1.00 8 of 225 January 15, 2015
Standard 8051 8-Bit Flash MCU
HT85F2260/HT85F2270/HT85F2280
List of Tables
List of Tables
Program Memory Register List ................................................................................................................ 33
FMAR0 Register – Flash Program Memory Address Register 0 ............................................................. 33
FMAR1 Register – Flash Program Memory Address Register 1 ............................................................. 34
FMAR2 Register – Flash Program Memory Address Register 2 ............................................................. 34
FMDR Register – Flash Program Memory Data Register ....................................................................... 34
FMCR Register – Flash Program Memory Control Register ................................................................... 35
FMKEY Register – Flash Program Memory Unlock Key Data Register .................................................. 36
FMSR Register – Flash Program Memory Status Register ..................................................................... 36
HT85F2260 Program Memory Contents.................................................................................................. 43
HT85F2270 Program Memory Contents.................................................................................................. 44
HT85F2280 Program Memory Contents.................................................................................................. 44
Security Bytes.......................................................................................................................................... 44
General Purpose Data RAM, 20H~2FH, Bit Address Map ...................................................................... 50
Special Function Register Bit Addresses Map......................................................................................... 51
Special Function Register Map................................................................................................................ 52
DPS Register – Data Pointer Select Register.......................................................................................... 54
DPC Register – Data Pointer Control Register........................................................................................ 55
PSW Register – Program Status Word Register ..................................................................................... 56
Crystal Recommended Capacitor Values ................................................................................................ 58
32768Hz Crystal Recommended Capacitor Values................................................................................. 59
System Clock Control Register – SCCR.................................................................................................. 62
High Speed Oscillator Control Register – HSOCR .................................................................................. 63
Low Speed Oscillator Control Register – LSOCR ................................................................................... 63
PLL Control Register – PLLCR ................................................................................................................ 65
PCON Register – Power Control Register............................................................................................... 67
WDT Register Contents ........................................................................................................................... 70
IEN0 Register .......................................................................................................................................... 70
IEN1 Register .......................................................................................................................................... 71
WDTREL Register ................................................................................................................................... 71
WDTCR Register ..................................................................................................................................... 72
IP0 Register ............................................................................................................................................. 72
Watchdog Timer Enable/Disable Control ................................................................................................. 73
LVDCR Register....................................................................................................................................... 75
Reset Source Summary........................................................................................................................... 76
RSTSRC Register.................................................................................................................................... 77
LVRCR Register....................................................................................................................................... 80
IP0 Register ............................................................................................................................................. 81
T2CON1 Register .................................................................................................................................... 82
CP0CR Register ...................................................................................................................................... 83
Software Reset Summary........................................................................................................................ 84
SRST Register......................................................................................................................................... 84
WDTCR Register ..................................................................................................................................... 85
LVRCR Register....................................................................................................................................... 85

Rev. 1.00 9 of 225 January 15, 2015
Standard 8051 8-Bit Flash MCU
HT85F2260/HT85F2270/HT85F2280
List of Tables List of Tables
Interrupt Register Bit Naming Conventions ............................................................................................. 92
Interrupt Register Contents...................................................................................................................... 93
IEN0 Register .......................................................................................................................................... 93
IEN1 Register .......................................................................................................................................... 94
IEN2 Register .......................................................................................................................................... 94
IEN3 Register .......................................................................................................................................... 95
IRCON Register....................................................................................................................................... 96
IRCON2 Register..................................................................................................................................... 97
S0CON Register ...................................................................................................................................... 98
S1CON Register ...................................................................................................................................... 99
TCON Register ...................................................................................................................................... 100
T2CON Register .................................................................................................................................... 101
T3CON Register .................................................................................................................................... 101
SPSTA Register ..................................................................................................................................... 102
CPICR Register ..................................................................................................................................... 103
I2CCON Register................................................................................................................................... 104
Low byte of Interrupt Priority Register 0: IP0 ......................................................................................... 109
High byte of Interrupt Priority Register 0: IP0H...................................................................................... 109
Low byte of Interrupt Priority Register 1: IP1 ..........................................................................................110
High byte of Interrupt Priority Register 1: IP1H.......................................................................................110
Low byte of Interrupt Priority Register 2: IP2 ..........................................................................................111
High byte of Interrupt Priority Register 2: IP2H.......................................................................................111
Low byte of Interrupt Priority Register 3: IP3 ..........................................................................................111
How byte of Interrupt Priority Register 3: IP3H.......................................................................................112
External Interrupt Trigger Type ...............................................................................................................112
CPICR Register ......................................................................................................................................113
TBCR Register........................................................................................................................................115
I/O Port Function Summary ....................................................................................................................118
I/O Register List ......................................................................................................................................119
P0 Register .............................................................................................................................................119
P1 Register .............................................................................................................................................119
P2 Register ............................................................................................................................................ 120
P3 Register ............................................................................................................................................ 120
P4 Register ............................................................................................................................................ 120
P5 Register ............................................................................................................................................ 120
Port 0 Mode Control............................................................................................................................... 121
P0M0 Register ....................................................................................................................................... 121
P0M1 Register ....................................................................................................................................... 121
Port 1 Mode Control............................................................................................................................... 121
P1M0 Register ....................................................................................................................................... 121
P1M1 Register ....................................................................................................................................... 121
Port 2 Mode Control............................................................................................................................... 122
P2M0 Register ....................................................................................................................................... 122
P2M1 Register ....................................................................................................................................... 122
Port 3 Mode Control............................................................................................................................... 122
P3M0 Register ....................................................................................................................................... 122

Rev. 1.00 10 of 225 January 15, 2015
Standard 8051 8-Bit Flash MCU
HT85F2260/HT85F2270/HT85F2280
List of Tables
P3M1 Register ....................................................................................................................................... 122
P0WAKE Register.................................................................................................................................. 123
SRCR Register ...................................................................................................................................... 123
Timer Function Summary....................................................................................................................... 127
Timer0/Timer1/Timer3 Register List....................................................................................................... 129
TL0 Register ......................................................................................................................................... 129
TH0 Register ......................................................................................................................................... 130
TL1 Register .......................................................................................................................................... 130
TH1 Register.......................................................................................................................................... 131
TL3 Register .......................................................................................................................................... 131
TH3 Register.......................................................................................................................................... 132
TMOD Register...................................................................................................................................... 132
TCON Register ...................................................................................................................................... 133
T3CON Register ................................................................................................................................... 134
TMPRE Register.................................................................................................................................... 135
13-bit Counter Data ............................................................................................................................... 136
Timer 2 with PCA Modules Operating Modes Summary........................................................................ 139
Timer 2 with PCA Modules I/O Pins....................................................................................................... 139
Timer 2 Register List.............................................................................................................................. 143
CCEN Register ..................................................................................................................................... 143
T2CON Register .................................................................................................................................... 144
T2CON1 Register ................................................................................................................................. 145
A/D Converter Register List ................................................................................................................... 154
A/D Data Registers ................................................................................................................................ 154
ADCR0 Register ................................................................................................................................... 155
ADCR1 Register .................................................................................................................................... 156
ADCR2 Register .................................................................................................................................... 157
ADPGA Register .................................................................................................................................... 158
A/D Clock Period Examples................................................................................................................... 159
A/D Converter Voltage Reference Select .............................................................................................. 160
DAH Register......................................................................................................................................... 164
DAL Register.......................................................................................................................................... 164
DACTRL Register .................................................................................................................................. 164
DAC Converter Voltage Reference Select............................................................................................. 167
Internal Voltage Reference Enable/Disable Control .............................................................................. 168
Comparator Registers List ..................................................................................................................... 171
CP0CR Register .................................................................................................................................... 172
CP1CR Register .................................................................................................................................... 173
CPHCR Register.................................................................................................................................... 174
CPICR Register ..................................................................................................................................... 175
I2C Register List .................................................................................................................................... 178
I2CCON Register................................................................................................................................... 178
I2CLK Register ...................................................................................................................................... 179
I2CSTA Register .................................................................................................................................... 180
I2CDAT Register .................................................................................................................................... 180

Rev. 1.00 11 of 225 January 15, 2015
Standard 8051 8-Bit Flash MCU
HT85F2260/HT85F2270/HT85F2280
List of Tables List of Tables
I2CADR Register ................................................................................................................................... 180
I2C Status in Master Transmitter Mode .................................................................................................. 185
I2C Status in Master Receiver Mode ..................................................................................................... 186
I2C Status in Slave Receiver Mode........................................................................................................ 187
I2C Status in Slave Transmitter Mode .................................................................................................... 188
I2C Status: Miscellaneous States .......................................................................................................... 189
SPI Register List .................................................................................................................................... 192
SPDAT Register..................................................................................................................................... 192
SPCON Register.................................................................................................................................... 193
SPSTA Register ..................................................................................................................................... 194
UART0 Register List .............................................................................................................................. 201
S0BUF Register – UART0 Data register................................................................................................ 201
S0CON Register – UART0 Control register........................................................................................... 202
S0RELL Register – UART0 Reload Low Register ................................................................................. 203
S0RELH Register – UART0 Reload High Register................................................................................ 203
SPPRE Register – UART Clock Prescaler Register .............................................................................. 203
SBRCON Register ................................................................................................................................. 204
PCON Register ...................................................................................................................................... 204
UART0 Operating Modes....................................................................................................................... 205
Mode 0................................................................................................................................................... 205
UART1 Register List ...............................................................................................................................211
S1BUF Register – UART1 Data register.................................................................................................211
S1CON Register – UART1 Control register........................................................................................... 212
S1RELL Register – UART1 Reload Low Register ................................................................................. 213
S1RELH Register – UART1 Reload High Register................................................................................ 213
SPPRE Register – UART Clock Prescaler Register .............................................................................. 213
UART1 Operating Modes....................................................................................................................... 214
Notes on Data Addressing Modes ......................................................................................................... 217
Notes on Program Addressing Modes ................................................................................................... 217
Arithmetic Operations ............................................................................................................................ 218
Logic Operations.................................................................................................................................... 219
Data transfer Operations ....................................................................................................................... 220
Program Branches................................................................................................................................. 221
Boolean Manipulation ............................................................................................................................ 222

Rev. 1.00 12 of 225 January 15, 2015
Standard 8051 8-Bit Flash MCU
HT85F2260/HT85F2270/HT85F2280
List of Figures
List of Figures
Stack Block Diagram ............................................................................................................................... 29
Program Memory Structure ..................................................................................................................... 31
Unlock Procedure Flowchart.................................................................................................................... 37
Page Erase Flowchart ............................................................................................................................. 38
Byte Read Flowchart ............................................................................................................................... 39
Byte Write Flowchart (FMCR.0=1, FMCR.6=0) ....................................................................................... 40
Byte Write Flowchart (FMCR.0=1, FMCR.6=1) ....................................................................................... 41
Internal Data Memory Structure............................................................................................................... 47
HT85F2270/HT85F2280 XDATA.............................................................................................................. 48
HT85F2260 XDATA.................................................................................................................................. 49
DPTRn Registers Control Block Diagram................................................................................................ 53
Crystal/Resonator Oscillator – HXT......................................................................................................... 58
External LXT Oscillator – LXT.................................................................................................................. 59
System Clock Congurations................................................................................................................... 61
PLL Frequency Changing ........................................................................................................................ 64
Watchdog Timer....................................................................................................................................... 69
Watchdog Timer Refresh Operation ........................................................................................................ 74
Power-On Reset Timing .......................................................................................................................... 78
Interrupt Structure.................................................................................................................................. 105
Interrupt Flowchart................................................................................................................................. 106
Time Base Clock Source Select .............................................................................................................114
Quasi-bidirectional I/O Structure............................................................................................................ 124
Push-pull Output Structure .................................................................................................................... 125
Open-drain Output Structure ................................................................................................................. 125
Input Only Structure............................................................................................................................... 125
Mode 0 and Mode 1 Block Diagram – Timer 0, 1, 3 .............................................................................. 136
Mode 2 Block Diagram – Timer 0, 1, 3 .................................................................................................. 137
Mode 3 Block Diagram – Timer 0 .......................................................................................................... 138
Timer 2 with PCA Modules Block Diagram ............................................................................................ 140
Capture Modes Block Diagram.............................................................................................................. 146
Compare Mode 0 – Module 1, Module 2, Module 3............................................................................... 147
Compare Mode 0 – Module 0 ................................................................................................................ 148
Compare Mode 0 Timing Diagram......................................................................................................... 148
Compare Mode 1 – Module1, Module2, Module 3................................................................................. 149
Compare Mode 1 – Module 0 ................................................................................................................ 149
Compare Mode 1 Timing Diagram......................................................................................................... 150
Reload Mode – Module 0....................................................................................................................... 151
Timer2 Clock Output Block Diagram...................................................................................................... 152
Programmable Clock Output Timing Diagram – Module 0 .................................................................... 152
A/D Converter Structure ........................................................................................................................ 153
A/D Conversion Timing .......................................................................................................................... 162
Ideal A/D Transfer Function (PGA=1) .................................................................................................... 163
DAC Basic Operational Block Diagram ................................................................................................. 166

Rev. 1.00 13 of 225 January 15, 2015
Standard 8051 8-Bit Flash MCU
HT85F2260/HT85F2270/HT85F2280
List of Figures List of Figures
Voltage Reference Generator Block Diagram........................................................................................ 169
Comparator 0......................................................................................................................................... 170
Comparator 1......................................................................................................................................... 171
I2C Master Slave Bus Connection.......................................................................................................... 177
I2C Interface Operation Flow.................................................................................................................. 177
I2C Block Diagram.................................................................................................................................. 181
I2C Bus Initialisation Flow Chart ............................................................................................................ 182
I2C Communication Timing Diagram...................................................................................................... 184
Single SPI Master and single Slave Connection ................................................................................... 190
SPI Interface Block Diagram.................................................................................................................. 191
SPI Master Mode Timing ....................................................................................................................... 195
SPI Slave Mode Timing – CPHA=0 ....................................................................................................... 196
SPI Slave Mode Timing – CPHA=1 ....................................................................................................... 196
SPI Transfer Control Flowchart.............................................................................................................. 197
Basic UART Data Transfer Diagram ...................................................................................................... 199
UART 0 Block Diagram.......................................................................................................................... 200
UART0 Mode 0 Timing Diagram............................................................................................................ 205
UART0 Mode 1 Timing Diagram............................................................................................................ 206
UART0 Mode 2 Timing Diagram............................................................................................................ 207
UART0 Mode 3 Timing Diagram............................................................................................................ 208
UART0 Baud Rate Generator................................................................................................................ 209
UART1 Block Diagram........................................................................................................................... 210
UART1 Mode A Timing Diagram............................................................................................................ 214
UART1 Mode B Timing Diagram............................................................................................................ 215
UART1 Baud Rate Generator................................................................................................................ 216

Rev. 1.00 14 of 225 January 15, 2015
Standard 8051 8-Bit Flash MCU
HT85F2260/HT85F2270/HT85F2280
Features
1 Features
CPU Features
■Operating Voltage:
●fSYS=3.6864MHz: 2.2V~5.5V
●fSYS=8MHz: 2.2V~5.5V
●fSYS=12MHz: 2.7V~5.5V
●fSYS=24MHz: 4.5V~5.5V
■Program Memory Capacity: 16K×8~64K×8
■Data Memory Capacity: 1280×8~2304×8
■High performance 1-T architecture: 8051
■Up to 32MIPS with 32MHz system clock at VDD=5V
■8051 compatible instruction set
■Flexible Power-down and wake-up functions to reduce power consumption
■Oscillator types:
●External high frequency crystal
●Internal high frequency RC
●External low frequency crystal
●Internal low frequency RC
■Multi-mode operation: Normal, Idle and Power-Down Modes
■Fully integrated internal 3.6864MHz oscillator requires no external components
■Internal PLL to multiply oscillator frequency up to 1~8 times for high speed system clock
■Watchdog Timer function
■Dual 16-bit data pointers with addition arithmetic operation

Rev. 1.00 15 of 225 January 15, 2015
Standard 8051 8-Bit Flash MCU
HT85F2260/HT85F2270/HT85F2280
Features Features
Peripheral Features
■Multi-channel 12-bit resolution A/D converter
■Single 12-bit D/A Converter
■Serial SPI Interface
■I2C Interface
■Dual UART Interfaces
■Dual Comparator functions
■Up to 48 bidirectional I/O lines
■16-bit Programmable Counter Array with 5 Capture/Compare Modules
■16-bit Programmable Counter Array
■Single Time-Base functions for generation of xed time interrupt signal
■Internal Temperature Sensor
■Low voltage reset function
■Low voltage detect function
■Package types: 48-LQFP and 64-LQFP

Rev. 1.00 16 of 225 January 15, 2015
Standard 8051 8-Bit Flash MCU
HT85F2260/HT85F2270/HT85F2280
General Description
2 General Description
The HT85F22x0 series of devices are Flash Memory A/D type high performance 1-T architecture
8051-Based microcontrollers. Offering users the convenience of Flash Memory multi-programming
features, these devices also include a wide range of functions and features.
Analog features include a multi-channel 12-bit A/D converter, a 12-bit D/A converter and dual
comparator functions. Multiple timers provide timing, capture, event counter and programmable
clock output functions. Communication with the outside world is catered for by including fully
integrated SPI, I2C and UART interface functions, popular interfaces which provide designers
with a means of easy communication with external peripheral hardware. Protective features such
as an internal Watchdog Timer, Low Voltage Reset and Low Voltage Detector and excellent noise
immunity and ESD protection ensure that reliable operation is maintained in hostile electrical
environments.
A full choice of both internal and external high and low speed oscillators are provided with the
internal oscillators requiring no external components for its implementation. A fully internal Phase
Locked Loop and the ability to operate and switch dynamically between a range of operating
modes using different clock sources gives users the ability to optimise microcontroller operation
and minimize power consumption.
The inclusion of exible I/O programming features, Time-Base functions along with many other
features ensure that the device will nd excellent use in applications such as electronic metering,
environmental monitoring, handheld instruments, household appliances, electronically controlled
tools, motor driving in addition to many others.
The HT85F22x0 series are Flash devices offering the advantages of easy and effective in-circuit
program updates. In addition, an EV chip, HT85V2280, includes an OCDS (On-Chip Debug
Support) interface for the In-Circuit Emulator.

Rev. 1.00 17 of 225 January 15, 2015
Standard 8051 8-Bit Flash MCU
HT85F2260/HT85F2270/HT85F2280
General Description Selection Table
3 Selection Table
Most features are common to all devices, the main feature distinguishing them are Program
Memory and Data memory capacity, A/D channels, UART numbers and packages. The following
table summarises the main features of each device.
Part No. VDD
Program
Memory
Data
Memory I/O Ext. Interrupt 16-bit Timer 16-bit PCA Time Base
HT85F2260 2.2V~5.5V 16K×8 1280×8 32 7 4 CCU×4 1
HT85F2270 2.2V~5.5V 32K×8 2304×8 48 7 4 CCU×4 1
HT85F2280 2.2V~5.5V 64K×8 2304×8 48 7 4 CCU×4 1
Part No. A/D D/A Comparator I2C SPI UART Temp.
Sensor package
HT85F2260 12-bit×7 12-bit×1 2 √ √ 1√48LQFP
HT85F2270 12-bit×9 12-bit×1 2 √ √ 2√48/64LQFP
HT85F2280 12-bit×9 12-bit×1 2 √ √ 2√48/64LQFP
Note: CCU stands for Compare/Capture Unit.

Rev. 1.00 18 of 225 January 15, 2015
Standard 8051 8-Bit Flash MCU
HT85F2260/HT85F2270/HT85F2280
Block Diagram
4 Block Diagram
The following block diagram illustrates the main functional blocks.
× ×
32768Hz
I
3.6864MHz

Rev. 1.00 19 of 225 January 15, 2015
Standard 8051 8-Bit Flash MCU
HT85F2260/HT85F2270/HT85F2280
Block Diagram Pin Assignment
5 Pin Assignment

 
      
      
























  
  
   
  
 


   


  
  
  









 
  
   
   
   
   
  
  
  




               
  
      
   
  

 













     






















 

           
        
  
   
    
  















   
  
  
  
  
  
 
 


  
  
  
  


 

  
  
  
               
  
    
Note: 1. If the pin-shared pin functions have multiple outputs simultaneously, its pin names at the right side of the “/”
sign can be used for higher priority.
2. For both the 48 LQFP-A and 64 LQFP-A packages, both real IC and OCDS EV IC share the same
package.

Rev. 1.00 20 of 225 January 15, 2015
Standard 8051 8-Bit Flash MCU
HT85F2260/HT85F2270/HT85F2280
Pin Descriptions
6 Pin Descriptions
With the exception of the power pins, all pins on these devices can be referenced by their Port
name, e.g. P0.0, P0.1 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, Serial Port pins
etc. The function of each pin is listed in the following table, however the details behind how each
pin is congured is contained in other sections of the datasheet.
Pin Name Function OPT I/T O/T Description
P0.0/ICPDA/TDA
P0.0
P0M0
P0M1
P0WAKE ST CMOS
General purpose I/O. Register selected I/O mode and wake-up
ICPDA — ICP Data Input/Output
TDA — Debug Data Input/Output
P0.1/C1OUT P0.1
P0M0
P0M1
P0WAKE
ST CMOS General purpose I/O. Register selected I/O mode and wake-up
C1OUT — — CMOS Comparator 1 Output
P0.2/SSN P0.2
P0M0
P0M1
P0WAKE
ST CMOS General purpose I/O. Register selected I/O mode and wake-up
SSN — ST — SPI Slave select Input
P0.3/SCK P0.3
P0M0
P0M1
P0WAKE
ST CMOS General purpose I/O. Register selected I/O mode and wake-up
SCK — ST CMOS SPI Clock
P0.4/MISO P0.4
P0M0
P0M1
P0WAKE
ST CMOS General purpose I/O. Register selected I/O mode and wake-up
MISO — ST CMOS SPI Master In Slave Out pin
P0.5/MOSI P0.5
P0M0
P0M1
P0WAKE
ST CMOS General purpose I/O. Register selected I/O mode and wake-up
MOSI — ST CMOS SPI Master Out Slave In pin
P0.6/SCL P0.6
P0M0
P0M1
P0WAKE
ST CMOS General purpose I/O. Register selected I/O mode and wake-up
SCL — — NMOS I2C Clock
P0.7/SDA P0.7
P0M0
P0M1
P0WAKE
ST CMOS General purpose I/O. Register selected I/O mode and wake-up
SDA — — NMOS I2C Data
P1.0/INT3/CC0
P1.0 P1M0
P1M1 ST CMOS General purpose I/O. Register selected I/O mode
INT3 — ST — External Interrupt 3 Input
CC0 — ST CMOS Compare/Capture input/output for PCA module 0
P1.1/INT4/CC1
P1.1 P1M0
P1M1 ST CMOS General purpose I/O. Register selected I/O mode
INT4 — ST — External Interrupt 4 Input
CC1 — ST CMOS Compare/Capture input/output for PCA module 1
P1.2/INT5/CC2
P1.2 P1M0
P1M1 ST CMOS General purpose I/O. Register selected I/O mode
INT5 — ST — External Interrupt 5 Input
CC2 — ST CMOS Compare/Capture input/output for PCA module 2