8-bit MicrocontrollersのトピックRe: problem with QD4, pin number 2

problem with QD4, pin number 2

Deepak1 — Sat, 28 Jul 2007 17:12:38 GMT

Dear sir,

I am using MCS908QD4,i want to turn on the SCR Connected to pin no. 2 & 5.

at first i used only pin no. 5 & pin no. 2 not in use.but there is no o/p on pin no. 5 & o/p at pin no. 2 showing some voltage.So plz tell me why i m not gettnig o/p,

my initial settings are like this,

SOPT1 = 0x50;
SPMSC1 = 0x1c;

SPMSC2 = 0x00;
ICSC1 = 0x00;
ICSC2 = 0x40;

ICSTRM = 0x99;

ICSSC = 0x01;
SRS =0x82;

SOPT2 = 0x00;

//*********************PORT INIT**************************************************

PTAPE = 0x00;

PTASE = 0x3f;
PTADS = 0x18;

PTADD = 0x18;

Re: problem with QD4, pin number 2

peg — Sun, 29 Jul 2007 09:21:28 GMT

Hi Deepak,

I am not exactly clear on what you are trying to say but here goes anyway.

Pin 2 is shared with then BKGD function.

This is enabled out of power up.

To use this pin as GPIO you disable this function by clearing 1,SOPT1 which you are doing.

But, this is a write once register, make sure the write you are showing us here is the only one that occurs.

Only the first write to this register is honoured!

Maybe this is your problem. If not please try again to explain your problem.