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PostPosted: Thu Apr 21, 2016 7:30 pm 
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Posts: 21
Hello,
This is my first time on this site so hopefully someone can help me out. I'm pretty new to all of this and I'm working on some boards I do not know the pinouts of, nor can I find anything online about them. The boards I'm working on are as follows: AOROM, TLSROM, SLRROM, SKROM, UOROM I'm ready to put the chips onto the boards but I'm unsure which ones to bend up and to connect to which holes. I'm fine with all the other boards but I cannot seem to find hardly any info on these ones at all. Here are the boards and the chips I will be using if anyone can provide me with the info that I seek.

AOROM - I will be using a 27C020
UOROM - I will be using a 27C020
TLSROM - I will be using a 27C010
SKROM - I will be using a 27C010
SLRROM - I will be using a 27C010

With the AOROM board I did find a pinout but it seems that it has an extra CE pin for bus conflicts at hole 31 and I'm not sure where to route the wire from this hole. I'm assuming it will be ground or +5V but I'm unsure where and what pin to put it to. Any help is very appreciated.

Thanks.


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PostPosted: Thu Apr 21, 2016 8:20 pm 
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Joined: Sun Sep 19, 2004 11:12 pm
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Location: NE Indiana, USA (NTSC)
The instructions for SxROM, TxROM, and UxROM should be similar. AOROM is a bit trickier because of the extra +CE used for bus conflict suppression. See Mask ROM pinout and NES EPROM Conversions.

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PostPosted: Fri Apr 22, 2016 10:15 am 
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Posts: 21
Thank you for your reply but that still leaves me with one question about the AOROM board. I understand the pinout of the board and the pinout of the chip I'm using, but I'm not sure about where to hook up the other CE(hole 31) and /CE hole. The links above just show a conversion and not a straight drop in for eproms. I have a wire soldered into hole 31 and hole 2 for it but I am unsure where to solder it to. Can you please explain, or even list which pins I should bend up. Here is my layout so far:

Bend up pins 1,2,24,30,31
Connect pin 1 to hole 30
Connect pin 2 to hole 24
Connect pin 24 to pin 16
Connect pin 30 to hole 1
Connect hole 2 to ???
Connect hole 31 to ???

Thanks


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PostPosted: Fri Apr 22, 2016 10:42 am 
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Joined: Sun Sep 19, 2004 11:12 pm
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Location: NE Indiana, USA (NTSC)
To convert an AOROM game to take EPROM, first follow the SNROM instructions, then invert R/W (the signal going to +CE on the AOROM PRG ROM) to make /OE for your EPROM. You can invert with a hex inverter, a quad NAND, a quad NOR, or plenty of other 7400-series chips you may have lying around your workshop.

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PostPosted: Fri Apr 22, 2016 12:02 pm 
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Joined: Thu Apr 21, 2016 2:47 pm
Posts: 21
This really isn't helping. I have hole 2 which is /ce and hole 31 which is ce. Can I just connect hole 2 to hole 31?

If not and once I run the wire from hole 31 to an inverter which pin should it go to on the chip. Als, which pin should the wire in hole 2 go to?

Thanks.


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PostPosted: Fri Apr 22, 2016 12:50 pm 
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Joined: Thu Apr 21, 2016 2:47 pm
Posts: 21
What I'm trying to make is an battle toads n double dragon. Could someone please list the exact steps needed to be taken to the prg eprom to wire this up correctly. I believe it can be done without adding extra gates, but I am unsure how it is done. If someone could help it would be greatly appreciated. Thanks


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PostPosted: Wed Apr 27, 2016 2:48 pm 
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Joined: Thu Apr 21, 2016 2:47 pm
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I still cannot figure this out. IF Someone Has The Wiring For The aorom, Please Let Me know. Thanks


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PostPosted: Thu Jun 30, 2016 11:35 pm 
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Joined: Thu Jun 30, 2016 11:19 pm
Posts: 13
Ok first post here so be gentle with me. I just got my aorom working today with battletoads loaded on a 29c020.
I'm sure something could be wrong but this is what got it working 100% stable for me.

Lift pins 1,2,24,30,31
connect pin 1 to hole/pin 32
pin 2 to hole 24
pin 24 to hole/pin 16
pin 30 to hole 1
pin 31 to hole 30
So that leaves hole 31 and 2 open. Bear in mind this is like the 5th cart I've ever modded so it's not like I know what I'm doing, so use at your own risk.


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PostPosted: Thu Jun 30, 2016 11:39 pm 
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Joined: Thu Jun 30, 2016 11:19 pm
Posts: 13
I'm also working on tlsrom and sl1rom if anyone can help.


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PostPosted: Mon Aug 01, 2016 6:46 pm 
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Joined: Wed Nov 25, 2015 7:54 pm
Posts: 41
I've tried applying Battletoads & Double Dragon onto an AMROM board with an extra wire for A17, works fine. Maybe on an actual AOROM board you have to take care of the extra chip enable signal, but it didn't seem to matter on one of the lower end AxROM boards.

TLSROM is the same as TLROM, except for the nametable mirroring control. There's info about it on the NesDev Wiki.


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