Rev. 1.10 2 November 26, 2019 Rev. 1.10 3 November 26, 2019
HT68FB240
USB Low Speed Flash MCU
Oscillator ........................................................................................................ 35
Oscillator Overview .............................................................................................................. 35
System Clock Congurations ............................................................................................... 35
Internal RC Oscillator – HIRC .............................................................................................. 37
Internal 32kHz Oscillator – LIRC .......................................................................................... 37
Operating Modes and System Clocks ........................................................ 37
System Clocks ..................................................................................................................... 37
System Operation Modes ..................................................................................................... 38
Control Register .................................................................................................................... 40
Operating Mode Switching ................................................................................................... 41
Standby Current Considerations .......................................................................................... 45
Wake-up ............................................................................................................................... 45
Programming Considerations ............................................................................................... 46
Watchdog Timer............................................................................................. 46
Watchdog Timer Clock Source.............................................................................................. 46
Watchdog Timer Control Register ......................................................................................... 46
Watchdog Timer Operation ................................................................................................... 47
WDT Enable/Disabled using the WDT Control Register ....................................................... 47
Reset and Initialisation.................................................................................. 48
Reset Overview..................................................................................................................... 48
Reset Functions ................................................................................................................... 49
Reset Initial Conditions ........................................................................................................ 53
Input/Output Ports ......................................................................................... 56
Pull-high Resistors ................................................................................................................ 56
Port Wake-up ........................................................................................................................ 57
I/O Port Control Registers ..................................................................................................... 58
I/O Pin Structures.................................................................................................................. 60
Programming Considerations ............................................................................................... 60
Timer Modules – TM ...................................................................................... 61
Introduction ........................................................................................................................... 61
TM Operation ........................................................................................................................ 61
TM Clock Source................................................................................................................... 61
TM Interrupts......................................................................................................................... 62
TM External Pins .................................................................................................................. 62
TM Input/Output Pin Control Registers ................................................................................. 62
Programming Considerations................................................................................................ 64
Compact Type TM – CTM .............................................................................. 65
Compact TM Operation ........................................................................................................ 65
Compact Type TM Register Description................................................................................ 66
Compact Type TM Operating Modes .................................................................................... 70
Compare Match Output Mode............................................................................................... 70
Timer/Counter Mode ............................................................................................................ 73
PWM Output Mode ............................................................................................................... 73
