#116951 - mog123 - Wed Jan 31, 2007 7:34 am
I know you need counters when designing a gba 8-bit rom flash cart, but i was thinking, if i could use 16bit eproms, would it still be necesarry to use counters?
#117027 - tepples - Wed Jan 31, 2007 9:49 pm
Yes. The counter is part of the definition of the GBA cart bus protocol. Without a counter, you just get one 16-bit word repeating itself 65,536 times in each 128 KiB bank, not bootable. If you have an EPROM with a 16-bit data output, go ahead and use it on a Sega Genesis cart. But you'll still need the 16-bit binary counter (e.g. four 74*161 chips) on a GBA cart.
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#117172 - Cyberman - Fri Feb 02, 2007 1:30 am
Ehh.. something you can 'count' on is needing that counter. It's how the interface works.
Either a CPLD/FPGA as a go between or some descrete logic is needed. Fun fun fun.. yeah.
Tepples, is the reset on the GBA connector an output or an input?
Cyb
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#117179 - tepples - Fri Feb 02, 2007 2:22 am
| Cyberman wrote: |
| Tepples, is the reset on the GBA connector an output or an input? |
Which pin number are you talking about? I don't see any called reset.
_________________
-- Where is he?
-- Who?
-- You know, the human.
-- I think he moved to Tilwick.
#117184 - Cyberman - Fri Feb 02, 2007 3:14 am
| tepples wrote: |
| Cyberman wrote: | | Tepples, is the reset on the GBA connector an output or an input? |
Which pin number are you talking about? I don't see any called reset. |
Well that kind of answers the question then doesn't it. I guess my memory is old /REQ[/IREQ, /DREQ] I guess is what I was thinking. (Weee).
LOL. Thanks for answering the question I should have looked at GBATEK!
Cyb
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