Thanks everybody for the explanation. Yes, I was wondering how many clock cycles the CPU executes/sec - looks like it's 1.8 million.

I've managed to get the simulator to run at > 3 million cycles/second after compiling it (it was running at 500K in the IDE). Not ideal but faster than the original ...

I should have been a bit more specific - my fault.

My opcode methods do already increment the number of cycles each opcode takes accurately depending on the address mode (varies between 2 and 7 cycles). My question should have read, how many of these cycles occur per second on the actual 6502? If ...

I have just finished my 6502 core in Real Studio and am currently testing all of the opcodes.

My end game is to emulate the NES. One thing I'm not sure about is how many cycles the 6502 (I know, it was actually a Ricoh chip, not a stock 6502) the chip in the NES was capable of executing per second ...

Thank you for the links to the test programs - I shall take a look.

This really is a great community

Excellent explanations - thank you very much.

I should have more faith in my own code!

On a related note, does anyone know of a good way of testing individual opcodes? Perhaps some software suite that I can check my code against?

Hi,

I'm working on a 6502 emulator in Realbasic (a Visual Basic like language).

I have implemented my ADC (add with carry) instruction thanks to a lot of help from this question on stackoverflow. My output was exactly as the question's answer's example output.

The problem is, I'm now not sure if ...