TQROM pinout

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TQROM pinout
by nintendo2600 on 2014-04-22 (#127958)
Hey,

I've looked but can't find a pinout for the TQROM pcb. It's got a 28pin package but is using 128k on the prg which confuses
the hell out of me. So I'm assuming the pinout must differ from more common nes pcbs. I only plan on using it for 32k or 64k of CHR and
64k of PRG and I'm taking the CHR RAM off as it's not needed for what I'm doing. If anyone has the exact pinout for this pcb to share
I'd be greatful.

Cheers,

Shawn
Re: TQROM pinout
by lidnariq on 2014-04-22 (#127962)
nintendo2600 wrote:
It's got a 28pin package but is using 128k on the prg which confuses the hell out of me.
That's perfectly normal. It's the JEDEC-standard 128KiB 28-pin mask ROM pinout, with a single output enable. Pin 22 is A16.
Re: TQROM pinout
by nintendo2600 on 2014-04-24 (#128059)
lidnariq wrote:
nintendo2600 wrote:
It's got a 28pin package but is using 128k on the prg which confuses the hell out of me.
That's perfectly normal. It's the JEDEC-standard 128KiB 28-pin mask ROM pinout, with a single output enable. Pin 22 is A16.


OK, I am just more familiar with 32pin 128k pintout is all.

So if I was using a 27512 does vpp from pin 22 on the eprom just get pulled high then and leave everything else as is?
Re: TQROM pinout
by lidnariq on 2014-04-24 (#128061)
nintendo2600 wrote:
So if I was using a 27512 does vpp from pin 22 on the eprom just get pulled high then and leave everything else as is?
No, pin 22 on a 27'512 is /OE. It needs to be low for the 'PROM to output data.
Re: TQROM pinout
by nintendo2600 on 2014-04-24 (#128066)
lidnariq wrote:
nintendo2600 wrote:
So if I was using a 27512 does vpp from pin 22 on the eprom just get pulled high then and leave everything else as is?
No, pin 22 on a 27'512 is /OE. It needs to be low for the 'PROM to output data.


ok so to the ground it will go! :)
Re: TQROM pinout
by Jon2887 on 2015-06-19 (#149477)
Were you able to get the game running? I'm fighting a TQROM trying to get it to run Mario Bros 2 Japan and its fighting me the whole way. I'm using 27c512 just like you were.
Re: TQROM pinout
by tepples on 2015-06-19 (#149485)
The MMC3 hack of SMB2 (J) needs work RAM at $6000-$7FFF. To add it to TQROM, you'll need to add a 74HC20 and a 6264 and a bunch of wires.