hi there, i am at the stage where i have got the addressing modes, memory map code, push & pop up and running on the nes emulator i an programming, i am now moving onto the instruction set, if there is anyone out there who has worked on a nes emulator - is the following function for the ADC instruction correct? (its pseudo code)
processor_stat_reg &= ~ CARRY_FLAG;
accum += value + (processor_stat_reg & CARRY_FLAG);
if(accum > 255) { processor_stat_reg |= CARRY_FLAG | OVERFLOW_FLAG; } else if(accum == 0) {
hw->cpu.processor_stat |= ZERO_FLAG; }
processor_stat_reg |= (processor_stat_reg & NEGATIVE_FLAG) ? OVERFLOW_FLAG: 0;
any help would greatly be appreciated thanks
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