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Title: Neo Geo MV2F Backup Ram Region 555 FF40 Post by: Claiker on August 28, 2013, 07:04:08 AM Hi.
I´ve got a MV2F, i use universal bios 2.3. when i turn on display Backup Ram region 00D00010 5555 FF40. I think the two rams between suicide battery and the bios could be the problem. I have tested the rams, some pins not signals, but i have not scheme to fix it. Do you have any idea how to fix it? Thanks. Title: Re: Neo Geo MV2F Backup Ram Region 555 FF40 Post by: Claiker on August 28, 2013, 07:47:04 PM I have not signal /we in both cxk58257.
thanks Title: Re: Neo Geo MV2F Backup Ram Region 555 FF40 Post by: channelmaniac on September 03, 2013, 02:26:37 AM Backup RAM is close to the battery... Look for the RAM that has pin 28 NOT connected to the +5v line on the JAMMA connector.
It's surface mount SRAM and you'll want to replace the one that is connected to the lower 8 data bus pins on the CPU. Title: Re: Neo Geo MV2F Backup Ram Region 555 FF40 Post by: channelmaniac on September 03, 2013, 02:27:20 AM Once you replace the bad Backup RAM it will continue on with the RAM tests and tell you if it finds any others as bad.
Title: Re: Neo Geo MV2F Backup Ram Region 555 FF40 Post by: Claiker on September 05, 2013, 09:23:18 AM thanks for responding.
one of the rams was very hot, could be wrong, I've removed. There are pins with corrosion. I need to buy another ram to replace the bad. The battery is removed, If I can I will put a picture. Is there any way of skipping the backup test ram? |