4 ms·
Great video and usually i love Ben's work, but, @ 7:48 he DECrements A which is not a valid instruction on the 6502 =(
by nicetryguy 3y ago
Great video and usually i love Ben's work, but, @ 7:48 he DECrements A which is not a valid instruction on the 6502 =(
- wkjagt 3y agoThe CMOS version (at least the one from WDC, which he uses) does have it.
- nicetryguy 3y agoAhhh i see. So technicallyyyyy it's a 65C02. All good. So if you're trying this code on an original 6502 it will not work, but easily modifiable to use the X or Y registers instead of A.
- tom_ 3y agoAll the CMOS variants have it, regardless of manufacturer. The manufacturer-specific instructions are: - RMB/SMB/BBR/BBS - Rockwell/later WDC only - WAI/STP - later WDC only
- wkjagt 3y agoAren’t WAI and STP only on the 16 bit versions? EDIT: just looked it up, and you’re right! The 65C02S has them. I thought I saw in the WDC programming manual that it was on the 16 bit version. I’m going to play around with those a bit :-)
- zaxomi 3y agoDon't they also have BRA - BRanch Always, PHX PHY PLX PLY - PusH or PulL X or Y register, STZ - STore Zero, TRB - Test and Reset Bits, TSB - Test and Set Bits?
- tom_ 3y agoYes, but those are common to all versions, not manufacturer-specific.