I build this circuit to control ac voltage... I attached the errors occured and the circuit too

Alec_t

Joined Sep 17, 2013
14,280
I don't use Proteus, but if I were simulating this I'd try a divide-and-conquer approach, by simulating functional blocks in turn, i.e first make sure the Arduino section works, then the lamp control section, then the LCD display section. Hopefully that would show up which section is causing the time-step problem.
 
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