1E2 error on a dontknow whatitis Slot Machine

[dormi]

This slot machine has no manufacturer's name any where, and appears to be a prototype.  Machine lites up but all it does is show error on candle of "1E2".  Questions are what is it and what is it trying to tell me?  Any answers or opinions are welcome.

thanks

[dormi]

Date codes on IC's are 1978.

[ROCKET]

looks familiar for some reason ?

SUMMIT
OR
SPECTRUM

[ROCKET]

looks familiar for some reason ?

SUMMIT
OR
SPECTRUM

its got 1978 chips o the board it looks -in fantastic condtion for year

[ROCKET]

most of the chips on the boards are made in 1978---7839 -which means 39th week of production =1978

the 1974 intel is from the orignial copyright

so i would say its a 1978 -79 machine

[Op-Bell]

I don't know exactly what it is, but it's very interesting! Thanks for the beautifully clear picture of the main board. It's remarkably unusual. The CPU is a 4040! That's a 4-bit processor, son of the ancestor of all microprocessors the Intel 4004. In my entire very long career, that's the first time I've ever seen one of those CPUs used in a commercial product. It came out in the mid-1970s at about the same time as the Intel 8080 and Intel pushed it a bit as a lower cost alternative - the 8080 cost over $150 at the time - but it never caught on. These days that chip family is completely unobtainable and the number of people who still remember how to work on it can probably be counted on your fingers.

Harrah's back then, when Bill Harrah was still running things, put in a lot of effort to develop their own slot machines - all ultimately unsuccessful. You are probably right that this is a proto. It looks a bit like a Bell Fruit mechanism, developed by the British Bell Fruit company. They were one of the pioneers of microprocessor controlled slots and I once had one of their games based on a 4004 microcontroller (in fact I still have the glass, which is quite attractive) so they would be a logical company to be offered a Harrahs contract, and it makes sense that they'd base it on their 4004 design and update it to the later processor. Red plastic reels was another of their characteristics. Bell Fruit - that would be my final answer if this was a Millionaire game.

[dormi]

Thats a great answer!  thank you

[Op-Bell]

A common kind of error would be that it hit for a cherry and there were no coins in the hopper. The problem is I can't see a battery on the main board so that it could remember the error through a power cycle. Another thing common with older machines is the optics that sense the reel positions get blocked with dust - assuming there are optics on this game - nah, it must have optics. Check it out and blow the dust out.

[dormi]

Three hard meters and no battery, only RAM is a 2102.  Each reel has a printed circut board with refelective type opto couplers looking at five rings printed on them for position sensors.  Only unidentified part on the board is the gold 24 pin IC mounted in about the center, it's been wiped clean of markings.  Single  EPROM a 2716 labeled 0E that I assume is a check sum doesn't equal the check sum as I get a 06 check sum. Don't like being a pessimist, but I'm thinking the EPROM is bit rotten and this machine is a goner