However, after several futile attempts of trying to get the activation email and not finding any info on who to contact (other than 'board administrator' with no specific contact info), I thought I'd try my luck here, as there is a high probability of someone knowing the answer.
So, I'm writing a 6502 emulator (just the processor), and I'm trying to understand how exactly the decimal mode works. I KNOW that when the flag is set, the processor considers each digit of a byte as a decimal number if the digit is in the range of 0-9, and if either digit is in the range of A-F, it is considered an invalid BCD number. All the examples I've seen are when the BCD number is valid, but what happens when it is an INVALID BCD?
for example, what would the result be in the following case?
Code: Select all
SED
LDA #$20
CLC
ADC #$1A
Also, if anyone could give me any info on who to contact regarding my problems on registration to 6502.org I would thankful.