HT48R30A datasheet(21/43 Pages) HOLTEK

21 / 43 page

HT48R30A-1

Rev. 1.10

July 2, 2001

ROM code option

The following table shows all kinds of ROM code option in the microcontroller. All of the ROM code

options must be defined to ensure proper system functioning.

Items

Option

WDT clock source: WDTOSC/fTID/RTCOSC/disable

CLRWDT instructions: 1 or 2 instructions

Timer/event counter clock sources: fSYS or RTCOSC

PA wake-up (By bit)

PA CMOS/SCHMITT input

PA, PB, PC, PG pull-high enable/disable (By port)

BZ/BZ enable/disable

LVR enable/disable

System oscillator

Ext. RC, Ext.crystal, Int.RC+RTC or Int.RC+PG1/PG2

Int.RC frequency selection 3.2MHz, 1.6MHz, 800kHz or 400kHz

Lock: unlock/lock

V DD

5. 5V

V LV R

0. 9V

R e s e t S i gnal

Re s e t

N o rm a l O p e ra t i o nR e s e t

LV R D e t e c t V ol t age

Low voltage reset

Note: *1: To make sure that the system oscillator has stabilized, the SST provides an extra delay of

1024 system clock pulses before entering the normal operation.

*2: Since low voltage has to be maintained in its original state and exceed 1ms, therefore 1ms

delay enters the reset mode.

HT48R30A Datasheet(PDF) 21 Page - Holtek Semiconductor Inc