Search found 134 matches

by poorstudenthobbyist
Mon Oct 26, 2020 12:10 pm
Forum: SNESdev
Topic: Retro Game Builder (make your own snes games)
Replies: 56
Views: 13734

Re: Retro Game Builder (make your own snes games)

Obviously it's not linear because if it was, it'd have estimated like $200k. Just pointing out that it's only been up for three days, and even then, it still estimates it gets pretty close, within a few thousand. Way too early to just write it off. Using a few points of data and filling in the next ...
by poorstudenthobbyist
Fri Oct 23, 2020 8:35 am
Forum: SNESdev
Topic: Retro Game Builder (make your own snes games)
Replies: 56
Views: 13734

Re: Retro Game Builder (make your own snes games)

I'm not running the Kickstarter, but I am helping! :D
I don't think I have the skills or bandwidth to make the software work! Haha
by poorstudenthobbyist
Sat Oct 17, 2020 10:31 am
Forum: SNESdev
Topic: SuperCIC 12F629 problem with Super Famicom console
Replies: 11
Views: 3863

Re: SuperCIC 12F629 problem with Super Famicom console

Sounds like the internal oscillator might be out of spec (assuming that is what it's running from). I looked in the datasheet and it has this note: The SuperCIC/SNESCIC always run off of external clock, so the internal calibration is irrelevant. (Also, different SNESes use different clocks: the ear...
by poorstudenthobbyist
Thu Oct 15, 2020 7:01 pm
Forum: Reproduction
Topic: I wrote up a Multicart guide
Replies: 0
Views: 728

I wrote up a Multicart guide

I've seen more than one person asking for help with multicarts, so I figured I'd write up a general guide to help beginners out. If you want to check it out feel free, and any criticisms are welcome. I wrote it in a few hours so I probably either forgot something important somewhere or worded someth...
by poorstudenthobbyist
Wed Oct 14, 2020 6:14 am
Forum: NES Hardware and Flash Equipment
Topic: SOLVED - Debugging an MMC3 Dev Cart
Replies: 9
Views: 3671

Re: Debugging an MMC3 Dev Cart

I've found that it's actually required to tie /CE to ground for most EPROMs due to timing issues. Not doing so often results in graphics glitches interestingly enough. Sorry for bumping such an old thread - but is this true? I had never heard of that before. Is that why /CE is normally tied to GND ...
by poorstudenthobbyist
Tue Oct 06, 2020 9:15 pm
Forum: Reproduction
Topic: Nes Noob Repro Starter help
Replies: 12
Views: 4623

Re: Nes Noob Repro Starter help

I just would much rather use 3 cents worth of combined parts instead of one 50 cent part. Well, nowadays you can get rather inexpensive 74'1g04s too. Those smaller packages weren't an option during the NES's commercial life, however. Maybe NoA really just wanted to use parts where if there was a pr...
by poorstudenthobbyist
Tue Oct 06, 2020 8:49 pm
Forum: Reproduction
Topic: Nes Noob Repro Starter help
Replies: 12
Views: 4623

Re: Nes Noob Repro Starter help

My best guess, without any good evidence, is resistor-transistor logic had some kind of compatibility problems. Maybe it was with the assembly method (can you wave solder a TO-92?), or maybe it was timing problems. Wave soldering TO-92's doesn't pose any problems, unless wave solder technology was ...
by poorstudenthobbyist
Tue Oct 06, 2020 7:23 am
Forum: Reproduction
Topic: Nes Noob Repro Starter help
Replies: 12
Views: 4623

Re: Nes Noob Repro Starter help

For ANROM, couldn't you just make a simple logic inverter for the R/W signal with an NPN, and wire it up to the previously-permanently-grounded /OE pin? That seems way easier than using an entire 16-pin logic chip to invert one signal. Why would Nintendo use that instead of just a transistor and two...
by poorstudenthobbyist
Sun Sep 27, 2020 8:34 pm
Forum: Reproduction
Topic: Nes Noob Repro Starter help
Replies: 12
Views: 4623

Re: Nes Noob Repro Starter help

Games originally shipped on AMROM boards explicitly do have bus conflicts; games originally shipped on ANROM don't; games on AOROM might or might not. Is there some newer documentation about which AOROM games have issues with having bus conflicts, besides Wheel of Fortune and Double Dare? Are there...
by poorstudenthobbyist
Mon Sep 21, 2020 6:55 pm
Forum: Other Retro Dev
Topic: Sega Genesis rom/sram address mapping
Replies: 37
Views: 38281

Re: Sega Genesis rom/sram address mapping

Krzysiobal made a schematic of a Sonic 3 a while ago here. There are PCB p0rn pictures on the begining of that same thread. Hope this can be usefull. Thanks for this, I did see this a while back and looked at it a bit again yesterday but missed the schematic. Though, I think that schematic raises m...
by poorstudenthobbyist
Mon Sep 21, 2020 6:14 am
Forum: Other Retro Dev
Topic: Sega Genesis rom/sram address mapping
Replies: 37
Views: 38281

Re: Sega Genesis rom/sram address mapping

Ok, thanks for that. So, going by this which was said earlier: For games with 2MB of ROM or less, there isn't an overlap, and there you would use a 74xx chip just to invert the chip enable signal for one of the ICs =P (so one gets enabled in the $000000-$1FFFFF range and the other in the $200000-$3F...
by poorstudenthobbyist
Sun Sep 20, 2020 9:46 pm
Forum: Other Retro Dev
Topic: Sega Genesis rom/sram address mapping
Replies: 37
Views: 38281

Re: Sega Genesis rom/sram address mapping

I'm having trouble finding the circuit, and I don't actually have a Genesis cart like that to check unfortunately. But even then, shouldn't this still work? Or do 16 Mbit games not use $A130F1 to pulse the /TIME signal? Also, one game did show save data when booting it up for the first time, it was ...
by poorstudenthobbyist
Sun Sep 20, 2020 9:37 pm
Forum: Other Retro Dev
Topic: Sega Genesis rom/sram address mapping
Replies: 37
Views: 38281

Re: Sega Genesis rom/sram address mapping

I made this circuit but I'm having some trouble holding some saves - it looks like the trend is games that are greater than 16 Mbit do not have any issues, but 16 Mbit and less do. I don't see why that would be a problem here, though. I'm a bit stumped.