Backplane EPROM

[smoothgrh]

Hey everyone,

What does the EPROM on the backplane actually do? I thought I could clear my game by changing the EPROM, but I guess that's what the 40 key chip is for.

I also thought that all the accounting information gets wiped out when you change that EPROM, but even after I changed it, all the statistics were still there. (After the error, and I turn the key, it does say it's updating the EPROM.) Are the stats stored on the base chip?

[rokgpsman]

I believe the chip on the backplane is actually an "eeprom". The extra "e" means it is an eprom that can be erased electrically , instead of having to be removed from the machine and exposed to UV light to erase.

eeproms are used when you want the cpu/mpu of the machine to be able to erase and rewrite data to the chip. On your slot machine the eeprom on the backplane stores certain data about your machine for security purposes, such as what game software is installed in your machine. On powerup the mpu checks the eeprom to see if what is has stored matches the game software and cmos ram data in the machine, to see if someone switched parts around. This is a security feature. The eeprom may also store a backup copy of the financial statistics for the machine, in case a battery failure on the mpu would kill the cmos ram data.

The eeprom is located on the backplane so that it is still in the machine if someone switches the mpu. It doesn't need a battery, it is like an eprom in that regard.

[smoothgrh]

Thanks rokgpsman for describing that so well!

[Badbaud]

The only way to clear the EEPROM data is with a KEY chip, that being said plugging in a new EEPROM that has never been programmed will also...... well.... clear the previous game information.

[smoothgrh]

The only way to clear the EEPROM data is with a KEY chip, that being said plugging in a new EEPROM that has never been programmed will also...... well.... clear the previous game information.

I put in a a new EEPROM that had never been programmed, but I think it copied the data from the MPU onto the EEPROM. If I remove the battery from the MPU, and put in a new EEPROM, would it clear the game? (In my other forum post, I'm trying to clear a Coin-Out Jam, despite having no hopper.)

[erbs]

The only way I have found out to clear a coin out jam is to key it.

[smoothgrh]

The only way I have found out to clear a coin out jam is to key it.

So even if I have credits on the machine, Key 22 or Key 40—or both—will clear it?

Thanks for the help!

[erbs]

Yes. Credits wont matter when you clear.