Denial

This kernal (PAL done, NTSC on request) tests the CPU during boot:
if CPU has the BCD flag bug then it's reported like as a normal N-MOS "6502",
if CPU execute opcode "SMB" then it will be classified as Rockwell "R65C02",
otherwise it will be classified as "65C02".

Now I can classify my fakes CPUs and use them for what really they are!


Another kernal that can be burned in a 27HC641:
http://sleepingelephant.com/ipw-web/bul ... 641#p99519

A Rockwell R65C02 is fake? What about WDC's W65C02S ?

I think he meant that many MOS6502s from China are in fact other types of 6502's.

WDC 6502 should have the STP and WAI opcodes...

Kakemoms wrote:I think he meant that many MOS6502s from China are in fact other types of 6502's.

If that is so then I would have to fully agree.

I still see people telling me "I got a sweet deal on a bunch of 6502s on Ebay". They don't like to admit that they got ripped of until they get them.

Is this really more convenient than a short program?
I suppose you can test it without storage hardware, but you have to open the case and swap out a ROM...?!

Floopy wrote:I still see people telling me "I got a sweet deal on a bunch of 6502s on Ebay". They don't like to admit that they got ripped of until they get them.

On the C64, a lot of programs use the illegal opcodes or intricate features of the NMOS 6502 (6510) either to make programs go faster or as part of a copy protection scheme but I truly don't know of any programs on the VIC-20 which would have problems running with a CMOS 6502 except for a few video/audio demos. I certainly don't know of any commercial programs having any problems.

In fact, on the VIC-20 using a CMOS 6502 is probably an advantage because it consumes only a small fraction of the power of the NMOS version and produces virtually no heat.

Since the 1541 drive is mostly used with the C64 then it may not be a good idea to use such an 'upgrade' there, at least if you intend to run demos or sophisticated software for the C64 which may include copy protected ones.

Also, CMOS 6502 can usually run at much higher frequencies than their NMOS counterpart. If you intend to use a 6502 CPU for a faster specific application then you may end up getting a free perk.

So, 'ripped off' is a relative thing.