Dr. Floppy wrote:
Memblers wrote:
Dr.Floppy, I made a cart a while back that does 4-screen nametables and has 4 channels of expansion sound (on NES, with no system mods needed). You interested? I have a bunch of the boards sitting around since I never built any to sell.
Very much so!!!
What do you want in exchange?
Since it would sorta be a DIY kit with rough software/firmware, not sure what I'd say about price. Including an RS232 adapter, I guess the cost of parts is under $20. If you have cash, post or PM me an offer (nothing is too low, since I've already had the parts sitting around forever
), but more than anything I'd be really pleased to see it used for a game.
Here is what the board looks like:
http://www.parodius.com/~memblers/nes/squeedo/pics/rev1.jpg
It uses a PIC18F4525 (@ 40Mhz, it has 48kB program memory and ~4kB of RAM), so for full control of the hardware you would need to do a little PIC18 assembly. The code I wrote (for the sound synth, communications, banking, IRQs) worked last time I used it (maybe 5 years ago?) but definitely is in need of some optimization in a couple spots. I could help with that some, but I won't have time to offer a whole lot of support.
This is the doc I had written on the registers and memory map:
http://www.parodius.com/~memblers/nes/squeedo/micromapper.txt
RS232 adapter is used to update the PIC firmware, also can be used for loading the NES program into FlashROM using XMODEM (though I can't remember if I ever wrote the code for it to load NES programs larger than 32kB). Alternatively you'd use a ROM programmer to use FlashROM up to 512kB or EPROM up to 1Mbyte. I did most testing using an EPROM emulator, because I had one and it was easy/fast.
There are some examples of the sound output (recorded through my TV at a really crappy samplerate though) here:
http://www.parodius.com/~memblers/nes/squeedo/samps/. But the pitch is messed up on some of them, turns out it was because of the music driver I was using (some version of MCK I hacked to replace namco106). I wasted a bunch of time trying to find a non-existent bug in the PIC code. The NES has to spend some time handling the sound too, it gets an IRQ and then writes the sound to the DAC ($4011 register), which actually works pretty well.
Let me know if you're not scared off yet, I understand if so. It would have been easier to use if I had developed it fully.
I quit working on this version of the hardware a long time ago, but more recently started planning a redesign (with extremely better hardware, but more cost to go with it..). That redesign won't be ready for a long time though. What I've done so far on it is rewrite my sound synth in C, there are some examples here:
http://membler-industries.com/squeedo/ (Castlevania, Lady Madonna, and TMNT4 all had an accidental distortion bug when I recorded them though)