Well, I got a BIG progress update today!
Blargg and I couldn't wait for the US postal service to deliver him his board. So naturally, we decided to forge ahead anyway. I sent him those high res. pics you can see a few posts ago, and he worked up a wiring diagram, We met on IRC to talk about the project, and he suggested remotely working on the cartridge. Then I set up an SSH tunnel to my home Linux computer so he could remotely control my NES via the special USB cable. After a bit of fiddling with the old NROM board to test the connection and some new code, I built the prototype board and we got it running with the Flash chip instead of EPROMs. Blargg tested some read and write functions, and we called it a day!
So, I have some pics and also some excepts from our IRC session.
First, A giant mess. Yes, that is what happens when you're working on something and don't care about keeping it clean in the process.
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The pcb front, now with socket and Flash chip (and some hidden trace cuts):
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The pcb back, now with 5 new jumpers and some trace cuts (details coming soon):
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And some IRC excepts:
<blargg> If you wanted to keep moving on development, you could do the wiring before I receive my board, then get it in the NES with a loader and hook it to your Linux box and then I could get debugging it remotely.
<arfink> oh, cool
<blargg> Assuming the wiring is good, the only thing I'd need from you is to reset the NES if I crash the loader :)
<arfink> I see
<blargg> I'd try to avoid that, so I could just sit here running tests remotely without any assistance.
<blargg> Since it'll be several days before I get my board at the soonest, I'm open to doing this to speed things up. Would also be pretty cool.
<blargg> You'd obviously create a separate account on your machine for me.
<blargg> Since I know you've got GCC and that test program compiled, I think all the libraries/packages are already there, so nothing to install.
<arfink> i feel like a freakin dentist here with my pick
<arfink> :)
<arfink> and cleaning brush
<arfink> ok, I'm pretty sure #2 is done
<arfink> and cap is back in place
<arfink> just 2 more cuts
. . .
<arfink> ok got one side done
<arfink> other side...
<blargg> And it's got a trace close to it, so you don't want to cut too far over the edge of the trace.
<blargg> ok, the flash id test :)
<arfink> try to ping again
<arfink> first
<arfink> ok
<blargg> yeah
<arfink> I think the cart was not quite seated right
<arfink> i got a beep
<blargg> yeah, writes work!
<blargg> FF FF 01 A4 FF FF
<blargg> first two are ROM, second two are the manufacturer and device code
<blargg> third two are ROM again
<arfink> coooool
<blargg> OK, now to try programming a byte... should work fine though
<blargg> gotta look up the writes
<arfink> yes
<blargg> and let's see how it needs to verify that they byte was written...
<blargg> works!
<blargg> I programmed a byte
<arfink> yup
<arfink> I heard the beep
* arfink does happy dance