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biggestsonicfan

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Here's something to get you started...
I made this for myself a while back but I find it super useful. I printed it out and have had it stuck to the wall next to my monitor for a couple of years now.
ts_eprom_xref.jpg


"on disk" is the size of the ROM file as it would be reported by windows
"in MAME" is the size of the ROM file as reported within MAME source

EPROMs within the same color group mean that you can double the ROM file and write it to the next size down the list.

obviously it's not comprehensive but it seems to cover 99% of the stuff I typically need to program.
I needed a replacement for some C27C202-90V05s and ordered some AT27C4096-90U replacements. Will the ROM files need to be modified to be put onto the EPROM?

EDIT: For reference, it appears each of my 4 binary ROM files are 128Kb and my device reads 4 interleaved EPROMs.
 
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MoppelTheWhale

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today i stumled across something new for me, an answer would probably best fit into this topic so here it goes:

i need to program a m27c2001 with two files, one should go in the upper half, one in the lower half - how do i do that?

i already tried adding them together with
copy /b "rom1.rom" + "rom2.rom" "rom_merge.rom"
also in reverse order, but unfortunately that didn't work.

should i use the offset option of my programming software (Prog-express/ Batronix) , that has the option for memory and buffer...

I also have a split option in the programmer, possible settings are all, odd, even, and first, second, third or fourth of 4...

Thanks for your help!
 

twistedsymphony

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i need to program a m27c2001 with two files, one should go in the upper half, one in the lower half - how do i do that?
that copy command you did should work; HOWEVER the rom files you're using need to be exactly half the size...

Code:
copy /b lower.rom+upper.rom combined.rom

an alternative command is the "type" command

Code:
type lower.rom upper.rom > combined.rom

I tend to do this one as it's a bit easier to remember, however it's technically "slower" and less safe

in either case you can use a hex editor like HxD to confirm that the lower ROM data is at the start of the file and the upper ROM data starts at exactly half way (0x20000)
 

MoppelTheWhale

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@twistedsymphony thanks got the eprom programmed, unfortunately still stuck even before the rom test - i'm about to test all programmed eproms against the files for a second time
 
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