early s plus doesnt register credits

[puckhead]

i have an early s plus, and in another post i stated one of the problems was it doesnt take credits when coined up.

i went into input tests 11_1 ( coin in B) and 12_1 ( coin in C) . both of those tests go from 1 to 0 when a coin is in the path of the coin optics.  i know test 10_1 is coin in A, which i believe is coin in with the door closed. that test does nothing with the door open, but it doesnt on my working machines either. i blocked open the coin comparitor to insure that any coin inserted would pass the optics. still doesnt add credits or give a coin accepted light.

well, i think that confirms the optics are good, and that the wiring to the cpu is good.  its there some kind of setting to prevent adding of credits?  maybe its time to do a ram clear?   cpu sees a signal from the coin optics, seems like its on a processor level.

figures i'm a month into this hobby, and i get this, but i actually like stuff like this. still, any help is appreciated.

thanks
mike

[rickhunter]

The comparitor triggers a signal when the coin passes through ok, if that signal is not seen by the cpu, then even if the coin passes the optic circuit, it will not register a credit.  All 3 coin in signals must be triggered in the correct order.  There is no setting to prevent coins from going to credits.  Take the sample coin out of the comparitor, is the coin rejected if you try it that way (i.e. coin goes to tray).  There is also a little white button where the optics are.  push the button to see if it will register a credit (done with door open and only used for testing purposes).  If it registers a coin in, then your optics are good and I would start looking at the comparitor harness since you have already tested the machine with the known good comparitor from your other machine.

[jay]

What do you mean by "coined up"
If you have a 3 coin machine, and 3 coins in the machine - the 4th coin does not go to Credit. It usually gets dumped back out to the coin tray.
There is an option on some game chips to support Montanna Credits (which is not the norm) which allows you to credit up the machine.
Some people set their bill validator to a penny and slip a $5 bill in to quickly bang on some credits.

[Shaggy]

What do you mean by "coined up"
If you have a 3 coin machine, and 3 coins in the machine - the 4th coin does not go to Credit. It usually gets dumped back out to the coin tray.
There is an option on some game chips to support Montanna Credits (which is not the norm) which allows you to credit up the machine.
Some people set their bill validator to a penny and slip a $5 bill in to quickly bang on some credits.

I agree with Jay. If you're wanting to just add credits to the the machine, you can tokenize it by using an SP1137 for normal style games not nudge or haywire type. There are more chips available for different style games.

[puckhead]

rick, thats in interesting point about the comparitor not just diverting the coins, but also signaling the cpu. i tested that on a working game by unplugging the comparitor and shimming the chute so coins go thru the optics, and yes, no credit is given.

on the non working game, i pressed the little test switch on the optics board , and it did give a credit.  i dont see an input test on the menu for the comparitor signal like 11_0 and 12_0 for the optics.  is there one ? im also curious, what is the purpose or test 10_1  if it doesnt work with the coin door open.  do you need a coin stick to check it with the door closed?  in the input tests, dropping a coin will not register , there has to be a coin in the path of the optics.   on a working unit, i may have to check the pins on the comparitor with a logic probe or scope , see what pin changes state when a coin drops, and then trace that wire back to the cpu.  i found some of the cc-16-c schematics online.

does anybody know what pin on the compatitor signals the cpu, and does it go high to low, or low to high? the is a pin marked credit, so im suspecting it may be that one. tracing it back to the cpu could be more of a problem.  also, is the comparitor on an model s plus 13v dc, or 24 ac?

sorry for all the questions, this is all new to me.

thanks

[jay]

Have you moved the working comparator to the non working machine ?

Coin comparators are cheap.
The letter behind the name such as CC-16D designates voltage.
The number is the coin type. 16 is quarter 33 is dollar.

[rickhunter]

Actually if you are doing the input/output tests the comparitor is activated and should respond as if it is operating normally.  The S+ uses a 24v AC comparitor.

[puckhead]

ive been doing some testing on a working machine, to try to figure out exactly how it works. i found some conflicting info on the web regarding the pinouts on the comparitor.  looking at the igt field service guide, it appears the violet wire on the comparitor is 6 volts, and drop to ground when a coin passes to signal the cpu,  i tried trying the violet wire to ground , and bypassing the comparitor to see what happens. code 21, thats what happens         i want to know how it works so i can them go to the broken machine and see if i can duplicate it.    i also put a little video recorder inside to see what the comparitor LED does.  i ordered a spare door optic. i want to make a test lead for it so i can operate the machine in door close mode with the door open.     

[Sunrise Side]

Have you  reseated all the cables at the  Motherboard board,  pull out the mpu and reset the connections on the motherboard  inside there, and the cables at the top of the mpu chassis?

[puckhead]

i did reseat all the connectors, didnt help. 

[puckhead]

i pretty much decided it was the violet wire coming off the comparitor.  what i like to do it find on the schematics where it ends, and buzz it out for continuity, or put a scope or logic probe on it and look for change at its terminus. . it was really tough for me to decipher the schematics. they are pretty blurry, and im not at all familiar with the layout, so i didnt find where it ended.

anyway, i decided i had to trace it out, follow it inch by inch.  i found a break in the wire, by a connector. the break was hidden in a long black sleeve. i only knew because i had one less wire coming in the sleeve out than going in.  it was too short to reach the connector, and even the molex was missing the pin it would have had on the end. it was like it was almost intentional, to hide it. anyway, i hard wired it in, and it works the way it should.

i didnt learn everything i wanted to know about exactly how it worked, but i know a heck of a lot more than i did, and its fixed.

thanks much
mike

[Shaggy]

Glad you got it going. And bravo for sticking it out, that sounded like a lot of work.   


Dave