t153
Member
my NVRAM just turned bad (the M48T58Y-Chip). Anyone able to help out with the code in this chip or the chip itself for dumping ? thanks.
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I have a Police 911/2, but I don't know anything about that chip or how to get its contents. Do you have any details about it... is the chip socketed, and are there any MAME dumps of Police 911/2?
DogP
Ah... I'm familiar w/ the timekeeper and zeropower chips. I just popped my case open, and unfortunately mine's not socketed :/ . What's the point of this chip, and why/how does it cripple the game? Is it meant as a security chip like a suicide battery kinda thing (pretty bad one if it's an off-the-shelf R/W NVRAM), or why can't it rebuild the NVRAM when a new chip is put in? Is it just making sure it's a valid time, and if so, couldn't you program the time on a new one and pop it in?
Also, my cab was upgraded from Police 911 to Police 911 2, so doesn't that mean you could use the NVRAM of Police 911, then "upgrade" to Police 911 2? The manual shows that the PCB is reused, and all you do is swap the CF card and the security plug.
DogP
Hes talking about the rtc "security plug" This is what is needed for the conversion from police 911 to police 911/2. I think I may have the conversion manual. Ill look for it
http://www.arcade-museum.com/vaps/
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Its an upgrade from the original
the rtc must be connected at all times to boot the new cf to the old pcb. Strange thing is that I have a japanese version that does not require a rtc to work with the original police 911. So it seems that theres different versions of the board out there.
Well no...my police 911/2 needs the rtc plug as its the conversion from the original. I have an original police 911 thats a Japanese version that doesnt need the rtc plug. I also have another original police 911 that needs the rtc plug. Not sure why this works like this
I thought that was kinda interesting... I had seen pics around where there were no security keys, but mine has one. Then looking at the manual, it says to remove old CF (store in safe place), insert new CF, insert security key... nothing about "remove old security key".
Also, when you write data to the Timekeeper, are you setting the time? IIRC you have to do a special operation to set the clock, and not just write it as you were writing the rest of memory.
DogP
Hey t,
I've been looking at this for awhile..try this. I believe that the nvram data is that same for world combat And police 911/2 ..same name and valued. World combats has been dumbed. Try to use that in place of police 911/2 that is undumped. Thinking out load that the values are the same it could work. Trying to remember I believe its nvram39 or similar that both games share. I'd give that a try.
Its either the same or they labeled them both nvram39. Or that because theres no dump for them..duno