Holtek HT66F488 Manual page 3

HT66F488/HT66F489
A/D Flash MCU with EEPROM
EEPROM Data Memory .................................................................................. 31
EEPROM Data Me�o�y St�uctu�e ........................................................................................ 31
EEPROM Registe�s .............................................................................................................. 31
Reading Data f�o� the EEPROM ........................................................................................ 33
W�iting Data to the EEPROM ................................................................................................ 33
W�ite P�otection ..................................................................................................................... 33
EEPROM Inte��upt ................................................................................................................ 33
P�og�a��ing Conside�ations ................................................................................................ 34
Oscillator ........................................................................................................ 35
Oscillato� Ove�view ............................................................................................................... 35
System Clock Configurations ................................................................................................ 35
Exte�nal C�ystal/Ce�a�ic Oscillato� - HXT ........................................................................... 36
Inte�nal RC Oscillato� - HIRC ............................................................................................... 3�
Exte�nal 32.�68kHz C�ystal Oscillato� - LXT ........................................................................ 3�
Inte�nal 32kHz Oscillato� - LIRC ........................................................................................... 38
Supple�enta�y Oscillato� ...................................................................................................... 38
Operating Modes and System Clocks ......................................................... 39
Syste� Clocks ...................................................................................................................... 3�
Syste� Ope�ation Modes ...................................................................................................... 4�
Cont�ol Registe� .................................................................................................................... 41
Fast Wake-up ........................................................................................................................ 42
Ope�ating Mode Switching ................................................................................................... 43
Stand�y Cu��ent Conside�ations ........................................................................................... 45
Wake-up ................................................................................................................................ 45
P�og�a��ing Conside�ations ................................................................................................ 46
Watchdog Timer ............................................................................................. 46
Watchdog Ti�e� Clock Sou�ce .............................................................................................. 46
Watchdog Ti�e� Cont�ol Registe� ......................................................................................... 46
Watchdog Ti�e� Ope�ation ................................................................................................... 48
Reset and Initialisation .................................................................................. 49
Reset Functions .................................................................................................................... 4�
Reset Initial Conditions ......................................................................................................... 51
Input/Output Ports ......................................................................................... 54
Pull-high Resisto�s ................................................................................................................ 55
Po�t A Wake-up ..................................................................................................................... 55
I/O Po�t Cont�ol Registe�s ..................................................................................................... 55
Pin-sha�ed Functions ............................................................................................................ 55
I/O Pin St�uctu�es .................................................................................................................. 55
I/O Po�t sou�ce cu��ent selection ........................................................................................... 5�
P�og�a��ing Conside�ations ................................................................................................ 5�
Rev. 1.21 3 �ove��e� ��� 2�1�