HT85F2250 datasheet(3/187 Pages) HOLTEK

3 / 187 page

Rev. 1.10

� of 187

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A/D Flash 8051 Core Low Pin Count MCU

HT85F2250/HT85F2262

Memor� Protection Contro� B�tes................................................................................................. 4�

18 RAM Data Memory.............................................................................................. 46

Str�ct�re............................................................................................................................ 46

Register Banks.................................................................................................................. 48

Bit Addressab�e Space ...................................................................................................... 49

Specia� F�nction Registers................................................................................................ �1

ACC Register – Acc�m��ator........................................................................................................ ��

B Register .................................................................................................................................... ��

SP Register – Stack Pointer......................................................................................................... ��

DPL� DPH� DPL1� DPH1 Registers – Data Pointer Registers...................................................... ��

Data Pointer Se�ect Registers ...................................................................................................... ��

Data Pointer Contro� Register....................................................................................................... ��

Program Stat�s Word................................................................................................................... ��

19 Oscillators ........................................................................................................... 56

S�stem Osci��ator Overview .............................................................................................. �6

System Clock Configuration.............................................................................................. �6

Externa� High Speed Cr�sta� Osci��ator – HXT ............................................................................. �6

Interna� High Speed RC Osci��ator – HIRC................................................................................... �7

Interna� Low Speed RC Osci��ator – LIRC .................................................................................... �7

20 Operating Modes and System Clocks .............................................................. 58

S�stem C�ocks Description................................................................................................ �8

Operation Modes............................................................................................................... 6�

NORMAL Mode ............................................................................................................................ 6�

IDLE Mode.................................................................................................................................... 6�

Power - Down Mode..................................................................................................................... 6�

Power Contro� Register ..................................................................................................... 6�

Standb� C�rrent Considerations ....................................................................................... 64

Wake-�p ............................................................................................................................ 64

21 Watchdog Timer.................................................................................................. 65

Watchdog Registers .......................................................................................................... 66

Watchdog Timer C�ock So�rce.......................................................................................... 69

Watchdog Timer Operation ............................................................................................... 69

22 Low Voltage Detector – LVD .............................................................................. 71

LVD Register ..................................................................................................................... 71

LVD Operation................................................................................................................... 71

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