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Rev. 1.40
2
March 29, 2019
Rev. 1.40
3
March 29, 2019
HT45F23A/HT45F24A
TinyPower
TM
Flash MCU with OPA & Comparators
HT45F23A/HT45F24A
TinyPower
TM
Flash MCU with OPA & Comparators
....................................................................................... 32
EEPROM Data Memory Structure .............................................................................................. 32
EEPROM Registers .................................................................................................................... 32
Reading Data from the EEPROM ............................................................................................... 34
Writing Data to the EEPROM ...................................................................................................... 34
Write Protection ........................................................................................................................... 34
EEPROM Interrupt ...................................................................................................................... 34
Programming Considerations ...................................................................................................... 35
Programming Examples .............................................................................................................. 35
External Crystal/ Ceramic Oscillator – HXT ................................................................................ 37
External RC Oscillator – ERC ..................................................................................................... 38
External Oscillator – EC .............................................................................................................. 39
Internal RC Oscillator – HIRC ..................................................................................................... 39
External 32.768kHz Crystal Oscillator – LXT .............................................................................. 39
LXT Oscillator Low Power Function ............................................................................................ 40
Internal 32kHz Oscillator – LIRC ................................................................................................. 40
Supplementary Oscillators .......................................................................................................... 40
Operating Modes and System Clocks .............................................................. 41
System Clocks ............................................................................................................................ 41
System Operation Modes ............................................................................................................ 41
Control Register .......................................................................................................................... 44
Fast Wake-up .............................................................................................................................. 45
Operating Mode Switching and Wake-up .................................................................................... 46
Standby Current Considerations ................................................................................................. 50
Wake-up ...................................................................................................................................... 51
Programming Considerations ...................................................................................................... 51
Watchdog Timer Clock Source .................................................................................................... 52
Watchdog Timer Control Register ............................................................................................... 52
Watchdog Timer Operation ......................................................................................................... 53
Reset Functions .......................................................................................................................... 54
Reset Initial Conditions ............................................................................................................... 57
Pull-high Resistors ...................................................................................................................... 60
Port A Wake-up ........................................................................................................................... 60
I/O Port Control Registers ........................................................................................................... 60
I/O Pin Structures ........................................................................................................................ 62
Programming Considerations ...................................................................................................... 62