That's interesting - some cases not yet covered by Klaus' tests. Could you raise an issue perhaps?
https://github.com/Klaus2m5/6502_65C02_functional_tests/issues
(If not, perhaps I can)

The bugs I just fixed were fairly harmless, and would only have any effect if the program counter was in the ...

I see you describe it as bug-free(!)
It looks like memory doesn't wrap around.

Could you point to where? I tried to always access withthe index as a uint16_t (which inherently wraps), or with "& 0xFFFF" when addition is involved.

Ah, you were right. Some of my address-mode decoding functions ...

Could you point to where? I tried to always access withthe index as a uint16_t (which inherently wraps), or with "& 0xFFFF" when addition is involved.

Well done! I see you describe it as bug-free(!) - does that mean you've passed Klaus' test suite? Or maybe a different test suite?

Perhaps my wording was too ambiguous, the "relatively" part was also meant to refer to the bugs :lol:

But yes, I have tested it with Klaus's tests, up to the part ...

Here it is: https://github.com/DavidBuchanan314/6502-emu

Nothing special, but it's completely free of macros which I personally find hard to read.

I started this project so I could debug programs for my SBC more easily, so it has the same hardware (so far only the 6850 UART is actually implemented ...

I'm currently working on a 6502 emulator in C. I have a few bugs to work out, but GDB support is high on my list of priorities.

The GDB protocol is fairly simple, so it really shouldn't be too much work to add.

Full Atari 2600 emulator:

https://www.youtube.com/watch?v=5nViIUfDMJg

It uses "command blocks" rather than redstone, but still very impressive.

Speaking of "a lot less wiring required," somewhere on the net I saw a bootup scheme for Z80 in which the host computer connected only to the Z80 clock and interrupt lines. (And reset, I guess, but still it was downright astonishing.) The gist of it was to stick the bytes in memory using the stack ...

My CH376S arrived today.

To my dismay, my arduino circuit still did not work after swapping out the new part. It turned out to be a silly programming mistake! (I forgot to set the A0 input accordingly.) I have updated the code I posted previously.

Update: I now have my arduino reading files with ...

3-Chip ROMless designs have been done in the past, using a microcontroller to load up the RAM.

However, all the ones I've seen so far have had the whole address and data bus wired up to the microcontroller. To save microcontroller pins, I came up with a much simpler design, that also works for CPUs ...

Oh dear, I seem to have bricked mine already. I had it working with my Arduino, and the GET_IC_VER command was returning a sensible value. I connected the INT pin to one of my Arduino pins before I had configured it as an input, and now the data lines are stuck at 0xFF.

Here's the arduino code I ...

Mine has just arrived, so I'm going to start testing.

It has an undocumented header on it, which I've determined out the pinout for (See attachment).
It has a serial mode, which I'll use to figure out how the protocol works.

I've been lurking for a while now, and it occurs to me that I never posted in this thread.

Although I'm 18, my first experience with programming was Usborne's " Introduction to Computer Programming: BASIC for beginners ", which I got from a second hand sale when I was around 8. I never had much ...

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> gung hfrf nqqerff yvarf sbe bhgchg.

Gung'f vg!

Guvf vf n irel vagevthvat pbaprcg. V npghnyyl hfrq fbzrguvat fvzvyne jura V jnf grfgvat zl FOP, gb oyvax na YRQ sebz bar bs gur nqqerff yvarf (jvgu n ohssre, bs pbhefr).

Qb lbh unir n ...

I came across this part on eBay recently.

It is very cheap (~£2), and lets you interface with USB mass storage devices over an 8-bit parallel bus (it also has some serial modes).

I'm still waiting for mine to be delivered, but it looks like a very cheap and simple way to add storage to a project ...