Hey all. Ok so im going a little bonkers and feeling bad about using my Uncharted Waters for Rockman 4 Minus Infinity. I got the label and the chips, just not the board. So i'll take my Rockman 4 out, and put Uncharted back. Im trying first to see if I can get an adapter (for Honeybee family adaptor, the long one) to use for any of the ETROM famicom games to fit in my toaster. (Also dont give me anything about buying the top loader please).
So I thought about designing my own EXROM board, so the PRG fits the JEDEC standard chip, and to hold CHR RAM by coping an ETROM board and lifting a MMC5 chip from a Laser Invasion. Altho what concerns me the most is really the board and pin dimensions. Does anyone have any of these dimensions? InfiniteNESlives? Ill be using express pcb
Do you already have a (hot air rework/"real" desoldering) station? It's not exactly trivial to get a 100-pin SMT part out without the right tool.
No I dont, but I didn't figure that it would be that much of a problem. Has anyone tried?
I believe infiniteneslives and myself have both posted board dimensions at some point, if I think of it later on I can try a search, but you may be able to find it. If the forum search doesn't help, try a Google search of the forum. But I can say that my board dimensions were almost too exact (the board manufacturer I've used can't route a perfectly square corner, so it only fit when trimming a bit of plastic off the case).
And yeah, express PCB.. that was my first experience with board layout. It was a good experience, but a couple disadvantages (unless they've changed in the past decade) is that first you're locked in to using them to make the board, and second, they used .063" thick boards - while regular NES boards are .047" thick. .063" boards will work, but it's not good for the NES connector. Game Genie's are that thickness, presumably so it can still make contact without being pushed down.
I've removed SMT parts with a normal heat gun, mostly little 20-pin ones and such, but I don't think it would be too different for a 100-pin part. When you don't care about preserving the board, it's even easier, you could just roast the hell out of it with a blowtorch (applying heat to the back of the board, not the component side). When it's hot enough, hold it upside down or sideways and smack it on a table (the board, not the chip of course, heheh).
When using a heat gun or hot air (and trying to save the board), you need to put something under the chip. I've not done it with a QFP, but I've heard that slipping a wire underneath the pins would work. With a SOIC part, I just stick an x-acto knife under the chip's body. At any rate, don't apply pressure. You continually move the heat gun around the part, and when the solder on all the pins is melted, the part will lift right off with minimum of effort. There's also some stuff called chipquik, which is solder that stays molten for longer. Not really necessary, but it would help.
Here are the thread I was thinking of, lots of dead links, but at least a couple posts have it in the text. Luckily, I knew the magic search term, "100mm".
http://forums.nesdev.com/viewtopic.php?t=5095&start=15And this one:
http://forums.nesdev.com/viewtopic.php?t=2162
Thanks, ill take a gander! I was gonna say I did find some stuff here and on the wiki all with dead links.
Oh and thanks for the info about the tqfp chip and express pcb
I actually joined to see if anyone had made a low-profile FC->NES adapter, to use the FC E_ROM boards in an NES shell. The donors there are cheap, so it seems like the optimal solution. I'm trying to use INL's Designspark layout, but Designspark is a real pain in the butt to use.
So far the best solution is to buy one of the converters on ebay, and mod your nes pins to bend UPWARD so you dont have to push the cartridge down for the NES to read the game. The game and the converter are just a HAIR too big to push downward in the NES. Very annoying! So thats what I did yesterday. I need a new 72 pin connector because the one I have was too old and the game has to be pushed down a few millimeters to work instead of directly.
I am still interested in mapping out my own MMC5 board for my own curiosity.