phase firing angle delay using 8051

you're using Timer 1 and checking for Timer 0 overflow flag

while(TF0==0);

fix it, and you can stop timer after delay is over (TR1 = 0)

yes i realized it yesterday. already fix it and it works as same as delay();

my actual problem is when i dont enable ex0, ADC is normal.reading environment normally. and lcd displays it normally.

then i enable ex0, which will check if functions inside ex0 routine. the result is power is correctly distributed (fulfill if function condition). but lcd cant displays it normally. sometimes all 1st row is balck box and some times random number appears.

what could be wrong? i think its software. but i cant figure out

LCD showing black boxes? is your circuit getting reset in the middle of operation? is there a power fluctuation?

sometimes random numbers, and then goes black boxes. but not always together. sometimes just random number, sometimes black boxes, sometimes both. no its not getting reset during process. the flow of the program is set ADC to works->write value to lcd->check zero cross,if the if function met then execute one of the condition.->back to displays reading of adc.

if i disables ex0, or at least not using delaying function inside ex0 routine it works normal. (so there are just two condition, full power and do nothing). i think delaying triac firing is the issue.

my guesses are:
-since triac driven by opto triac (moc 3021) which means high speed switching, so there might be noise.
-or since delay is resulting in different power output, it might cause power fluctuates?
-or delay that inside routine is 'delaying' other process that shouldnt.

because the power distribution seems okay but the display is a mess.
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updated: it is fixed. i interface the lcd away from the main circuit. looks like there is noise there. display is now normal.

when i delay 5ms (90 degree) i got 108.6 on my dvm. when i look up in internet, 90 degree means i got 155 Vrms. is it mean what i got is average voltage? how come i sourced it with 220 Vrms main, and then get average for the reading on dvm?

what actually that i had done here, is it integral cycle control, phase firing angle, or another method of controlling ac voltage using thyristor that i do not know its name?