quick mapper question and eprom question

Discuss hardware-related topics, such as development cartridges, CopyNES, PowerPak, EPROMs, or whatever.

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sleepy9090
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quick mapper question and eprom question

Post by sleepy9090 » Wed Aug 27, 2008 1:51 pm

1. From what I understand if i make say a cnrom dev cart, then any cnrom i dump to a eprom and load in the socket should run?

2. I picked up some 8Meg eproms with the uv window, i can use these correct? even though it is overkill (got them free)

3. Any place that shows how to create dev carts or I am to get the datasheets and figure it out =)


thanks all

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MottZilla
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Post by MottZilla » Wed Aug 27, 2008 2:04 pm

I would really advise against using a 8Mbit EPROM for a CNROM game. That is a HUGE waste and these EPROMs aren't made anymore.

Yes if you make a CNROM cart with sockets you could load any CNROM game into it.

I'm not sure what the wiring is for CNROM but the main NESDEV page has a document with EPROM info.

sleepy9090
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Post by sleepy9090 » Wed Aug 27, 2008 2:58 pm

I know it is a big waste, but I have a whole lot of old cable modems that are getting pitched, im talking at least hundred or so, each one has an 8M eprom in it, so it's free and there is plenty

thanks for the tip, I will check out that part of the forum

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kyuusaku
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Post by kyuusaku » Wed Aug 27, 2008 5:15 pm

If I had 100x 27080s I'd erase then sell them for $300-400 and get a PowerPak. (Or make a 32-game CNROM multicart with two of the ROMs and sell the rest.)

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MottZilla
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Post by MottZilla » Wed Aug 27, 2008 8:23 pm

kyuusaku is right. You should harvest them and sell them for a PowerPAK if you want to play games on your NES. 8MBit EPROMs have much better uses like SNES or Genesis cartridges or really anything other than a CNROM game. I wish I had 100 8M eproms. =(

sleepy9090
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Post by sleepy9090 » Thu Aug 28, 2008 7:50 am

I might end up doing that to get a power pack, but I like wiring and soldering anyway so im gonna make a few this way, I would be willing to trade off some 8meg chips for other hobby items if someone wants some of them that badly. I work for a cabletv/internet provider and we are in the process of upgrading docsis and the old modems are not compliant anymore. I tried several cm configs and these modems are about the jankest, so its nice that i can harvest something from them before they get pitched.

looks like the power paks are sold out right now, but that does look awesome, i would rather play it on real nes hardware and not the xbox, dc, pc, etc, i will have to read more, i do not see that it does save states

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Bregalad
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Post by Bregalad » Thu Aug 28, 2008 11:09 am

Oh if I you have lots of 27C080 for free you should immediately move to SNESdev.
Other than that I belive they're 32 pins (if not even more ?) and the slots in CNROM are 28 pins so you'll be in trouble if you use any EPROMs greater than 64k for a CNROM board. Of course you could make it to work but that'd be somewhat stupid when the 27C256 (32kx8) is really the most common EPROM arround, and it's the one that fit perfectly CNROM boards.

I don't know if 27C080 aren't made anymore (or they're called 27C8001), I guess there is some of them but they are definitely expensive and less common. Those are the higher capacity EPROMs I've ever seen in catalog, tough. I don't know what you are supposed if you make a SNES game of 2MB, 3MB or 4MB. You are basically forced to jungle with '138 or '139s and make stacks of EPROMs which sucks.
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kyuusaku
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Post by kyuusaku » Thu Aug 28, 2008 1:15 pm

Bregalad wrote:Those are the higher capacity EPROMs I've ever seen in catalog, tough. I don't know what you are supposed if you make a SNES game of 2MB, 3MB or 4MB. You are basically forced to jungle with '138 or '139s and make stacks of EPROMs which sucks.
There's 2Mx8 = 27C160 and 4Mx8 = 27C320, or you can use very common FlashROM 28F016 and 28F032 (surface mount).

sleepy9090
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Post by sleepy9090 » Fri Aug 29, 2008 6:05 am

Well I got my eprom eraser and willem programmer yesterday. I am able to read the winbond chips however when I read the 8M chips I get a different checksum each time so I wonder if the willem is having trouble with these chips. M27C801, so I use the settings for 27c080/801. Google doesn't not have much info.

well i guess i will wait till tonight to mess with it more, in the meantime im bored so coding a c# version of the game genie decoder

Which roms are 32pin that I can use these for?, I'm sure I can score some 28 pin roms off ebayz for the cnroms, i was just starting with that because it appears to be easiest.

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