From: Memblers (jparsell317_at_comcast.net)
Date: 2003-02-26 02:42:28
On 26 Feb 2003 at 1:59, Groepaz wrote: > mmmmh both my NES and my PCE port are currently compiled with --cpu 65C02 > -Ori. i link those files to a "none.lib" which i have compiled --cpu 65C02 > and C-file(s) also compile --cpu 65C02. That could be a problem. The NES's CPU (2A03) is based on the older NMOS 6502. Any of the added 65C02 instructions will turn out as invalid opcodes. Another difference is that it has no decimal mode. SED and CLD will affect the decimal flag, but it has no effect on ADC/SBC. Decimal mode probably wouldn't be needed by cc65 anyways, would it? On 25 Feb 2003 at 13:32, Shawn Jefferson wrote: > Maybe it's time I actually find out the difference between the 6502 and the 65c02. :) 65C02 has a few more opcodes. STZ (store zero), BRA (unconditional branch), and INC A (increment accumulator). I think that's the only difference from the programming point-of-view, but they are useful opcodes. peace. Memblers http://www.parodius.com/~memblers/ ---------------------------------------------------------------------- To unsubscribe from the list send mail to majordomo_at_musoftware.de with the string "unsubscribe cc65" in the body(!) of the mail.
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