Hey guys, well ive been so close to getting a rom split and ready for programming. the first game im making is super mario brothers 2 Japanese version, and i already download the mmc3 hack version and split the rom. Now all i have to do is data mirror it for programming, but i have no idea how to do it. If someone could please help that would be great. i know the CHR for mario 2 is only 16 KB and the eproms i have are 512 KB so i have to duplicate it a lot. i have the willems eprom programmer and im using the hex workshop 4.2 software. If anyone has any info please send me a PM, or better yet a instant message on AOL Instant Messenger. my username there is parpunk Thanks guys!
-mark
Hey! Note that you don't have to mirror the data if you connected the unused address lines of the chip to GND, as that will make it impossible for the chip to output anything other than the data in the beginning of it.
However, if the state of those address lines is unknown, you'd better replicate the data. I guess that a simple copy & paste procedure could be done in the hex editor, give it a try. If that fails for some reason, try using a command prompt box (if you're using windows). The command "copy /b file.chr + file.chr file2.chr" will result in the file "file2.chr" holding the data from "file.chr" twice. Of course you can replicate it more times, like "copy /b file.chr + file.chr + file.chr + file.chr file4.chr", where "file4.chr" will have the content of "file.chr" replicated 4 times. Do that as many times as you need.
Hey dude, thanks a lot for the input. i would like to take the address lines to the gnd. Thats pin 16 right? What exactly do you mean by the address lines?? Please lemme know asap. ive been waiting all day to find someone who knows about this. thanks!
All the pins labeled "Axx" are address lines. These tell the chip what address to read from. However, the CHR data you have is much less than the size of the chip. By connecting the unused address lines to GND, you'll make it seem like your chip is only 16KB.
Since 16KB is 16384 bytes, and 2^14 is 16384, that means only the first 14 address lines are needed to address the CHR data. So, A0 through A13 should be connected accordingly, but A14 to A18 should all go to GND. I don't know what chips you're using, so you'll have to check out it's pinout and see where exactly those address lines are.
hi man thanks for the info. do you happen to have aol instant messenger?? if so please send me a message and we can discuss it more. user name is parpunk .....i really hope i can figure this out. heres the exact eproms i bought>
http://cgi.ebay.com/ws/eBayISAPI.dll?Vi ... 0083568304
Do you happen to a know a chart that shows which pins would be the AXX on these. also to take the pins to the ground you mean take a wire from them to the GND? How many wires you think i will be running on those. please let me know man, im sooooo close. lol
also how would you successfully take about 10 wires from the AXX pins all to the gorund. would that be like 10 wires to one GND and make a big mess or there a decent way of doing it?
You're doing a bunch of rewiring instead of duplicating the data in a hex editor?!? Why?
blargg wrote:
You're doing a bunch of rewiring instead of duplicating the data in a hex editor?!? Why?
I guess it's because I said he didn't
have to replicate the data. But I guess he decided to go with the replication, though.
Although since he is converting a cart for EPROMs, he will have to rewire many of the higher address lines anyway, and would be easier to solder them all to GND than look for holes and all that, don't you think?
But maybe since he's a beginner at this, maybe he should go with the standard procedure.