I find this thread very timely. I normally do a lot of pinball work and a friend of mine referred someone to me who has a Racing Jam board that gets an RTC error. He has had ZERO luck finding anyone who can help so I'm going to give it a try. I found some replacement timekeeper chips and when I researched them I figured it was just battery backed RAM. However after reading this thread it appears that there is some kind of image stored there too. Is that the case? If it is then I guess I need to find the image file too. My programmer supports the M48T58Y device so I will try to read the old chip first and hope I can pull the file from there, assuming the battery is OK.
Before I start - for those who may know, is that the normal procedure for these devices? Program them with an EPROM burner for the game they're being used for? If that's true then I guess the game's program must then use the memory space as RAM and not ROM, or they would have just used an EPROM, right?
I'd love to see some documentation about the theory of operation for these machines to get insight on what the program is doing, and how it uses this device. Even a schematic would be great.
One more question - is there a way to check the condition of the battery on the device? I'll go and find the datasheet but I just thought I'd ask you guy (and gals) first.
Thanks for any insight from this MAME-newb.