I decided to mess around with another IGT machine called the "S-Plus (S+)". This machine is strictly a mechanical slot machine with no real video.
The hardware is similar to the PE+ machine but lacks video and contains optics for the reels.
There is a bunch of 7-segment display for some form of output, and interesting navigation procedures to view various operator values.
Once I got a skeleton driver working, I started to hookup the inputs and the 7-segment displays. After much work, I finally got the display to show the first error code. This is an error 61 or "Bad CMOS RAM". Sound familiar? It should, the PE+ generates this error the first time you boot the machine with empty RAM and empty EEPROM data. When I saw this error code come up, I knew I was on the right track.
The proper procedure to recover from this error is to open the door and press the Self-Test button. After doing that, the follow error code appears. This is an error 61-1 which represents "Game Data Reset". What needs to be done at this point is to close the door and turn the jackpot reset key.
Doing that produces the next error code, 65-3 which is "Game Options & Meters Not in the Most Current Format". This can be corrected with a Set Chip, or you can just turn the jackpot reset key and have it overwritten.
I chose to allow the machine to overwrite the values and turned the jackpot reset key. A new display appears with the "0" flashing as the CMOS data is reloaded. Now the next error code appears, 65-1 or "Bad EEPROM Data". Once again a error message I've seen on the PE+ machine. To resolve this you must open the door and press the self-test button.
Finally, the last screen appears which should be error free, however I get the following code, 41 which says "Reel 1 Tilt". This means the machine was unable to process the first reel properly.
So this is where I'm currently at today. From this screen I can go into all the operator self-test screens and play around with the machine settings and listen to the built-in sounds, but I get held up eventually trying to activate the reels.
Time to investigate the Reel Optics next. It should be an interesting challenge.