6502.org

what differences between the w65c816sxb and w65c02sxb ?

I tried the w65c816sxb I'm so deceived that I'm thinking to trash it and buy the w65c02sxb

I found the board nice for it's speed, but I found the compiler and debugger useless
and I have problems with the w65c816sxb in emulation mode (while crossing $FFFF)


except for the processor I will find the ACIA, PIA, VIA at the same place ? and an usb uart fifo connected to a via ?
I'm thinking to use it with my own firmware, cc65 or 64tass

thanks for your advices

(If you have something you no longer want, there might be someone here happy to accept it...)

I suspect you'll have largely the same issues with the 65C02SXB but the page wrapping will work as you expect.

The 65C816 is best thought of as a completely different CPU rather than as a suped up 6502. Having 16-bit registers completely changes the way you access memory and you are not so dependent on zero page. The WDC C compiler for example overlays the direct page onto the stack to provide quick access to function arguments and locals, not its traditional use at all.

I have some projects on GitHub that program the 816SXB in assembler using the WDC tools that you could use as a starting point. I have been meaning to put up a C demo but I have too many other things going on at the moment to do that right now.

Of all the SXB boards I think the W65C265SXB is the best. Its has a built in monitor (which can be disabled by your code if needed) with S28 SREC download (so you can use any assembler that outputs S28 files - like my one does). It is much easier to add more RAM to (just a chip and some wires) and its cheaper.