Holtek BS82B12A-3 - Page 3

Rev. 1.20 2 January 23, 2015 Rev. 1.20 3 January 23, 2015
BS82B12A-3/BS82C16A-3/BS82D20A-3
Touch Key 8-Bit Flash MCU with LED/LCD Driver
BS82B12A-3/BS82C16A-3/BS82D20A-3
Touch Key 8-Bit Flash MCU with LED/LCD Driver
Writing Data to the EEPROM ................................................................................................ 43
Write Protection ..................................................................................................................... 43
EEPROM Interrupt ................................................................................................................ 43
Programming Considerations ................................................................................................ 44
Oscillator ........................................................................................................ 45
Oscillator Overview ............................................................................................................... 45
System Clock Congurations ................................................................................................ 45
Internal RC Oscillator – HIRC ............................................................................................... 46
Internal 32kHz Oscillator – LIRC ........................................................................................... 46
External 32.768kHz Crystal Oscillator – LXT ........................................................................ 47
LXT Oscillator Low Power Function ..................................................................................... 48
Operating Modes and System Clocks ......................................................... 48
System Clocks ...................................................................................................................... 48
System Operation Modes ...................................................................................................... 50
Control Register .................................................................................................................... 51
Operating Mode Switching ................................................................................................... 53
NORMAL Mode to SLOW Mode Switching ........................................................................... 53
SLOW Mode to NORMAL Mode Switching .......................................................................... 54
Entering the SLEEP Mode .................................................................................................... 54
Entering the IDLE0 Mode ...................................................................................................... 55
Entering the IDLE1 Mode ...................................................................................................... 55
Standby Current Considerations ........................................................................................... 55
Wake-up ................................................................................................................................ 56
Programming Considerations ................................................................................................ 56
Watchdog Timer ............................................................................................. 57
Watchdog Timer Clock Source .............................................................................................. 57
Watchdog Timer Control Register ......................................................................................... 57
Watchdog Timer Operation ................................................................................................... 58
Reset and Initialisation .................................................................................. 59
Reset Functions .................................................................................................................... 59
Reset Initial Conditions ......................................................................................................... 61
Input/Output Ports ......................................................................................... 65
I/O Register List .................................................................................................................... 65
Pull-high Resistors ................................................................................................................ 66
Port A Wake-up ..................................................................................................................... 66
I/O Port Control Registers ..................................................................................................... 66
I/O Pin Structures .................................................................................................................. 66
Source Current Selection ...................................................................................................... 67
Programming Considerations ................................................................................................ 68
Timer Modules – TM ...................................................................................... 69
Introduction ........................................................................................................................... 69
TM Operation ........................................................................................................................ 69
TM Clock Source ................................................................................................................... 69
TM Interrupts ......................................................................................................................... 70