WMS 550 NXT upgrade - MC-40 Coin Comparator

[rokgpsman]

http://www.coinmech.com/product_profile.cfm?id=44

[fmetz374]

Thanks for the great documentation.  Regarding the Multi-color status LED.  I've never actually seen it turn green.  I've seen red and orange but never green.  Per the documentation the LED will be orange if the inhibit line is active.  Any suggestions why I'm seeing orange even though I've selected MC40 in the machine setup of the game?


The MC incorporates a bi-color (green / red) LED on its front cover to easily indicate the operating status of the
mechanism visually. The LED will be green when power is applied to the device and it is enabled (INHIBIT not active)
to accept coins. The LED will be orange if the INHIBIT line is active (disable coin acceptance). The LED will be red
when the TILT line is active (error condition) or if there is no resident coin in place.

[rokgpsman]

Sorry, I don't know the answer to that, maybe one of the folks knowledgeable on that model of machine can say. I was hoping the documents would have full information. But I'd think the inhibit line would be coming from your machine mpu to enable or disable the MC-40, so that may be what is the cause of your problem, have to find out why that inhibit line isn't enabling the MC-40. If you were to remove the inhibit pin (with wire attached) from the connector temporarily would that let the MC-40 work?

I suppose you have verified the cabling, making sure it is plugged in to wherever it goes (backplane, mpu, etc) and that there isn't a broken wire or a connector pin pushed back? Or was something perhaps overlooked or miswired when you made your adapter cable for the MC-40? Rickhunter will check back in later, he is experienced with this machine, maybe he will have suggestions, particularly on the adapter cable construction and the inhibit function.

[fmetz374]

Well I am happy report that my coin comparator is now working! And with tokens which is what I was hoping to accomplish.  I am rather embarrassed to share that the issue was with the connector on my harness to the MC-40.  I originally had tested the harness for continuity and all of the pins checked out good between both end of the harness.  Unfortunately two of the pins inside the connector going to the MC-40 7-pin header were not making a connection.  When I did a continuity test to the header pins on the MC-40 PCB I noticed the top two pins did not have continuity.  I pulled these two pins out of the connector and bent them out a bit and problem solved!


I should have thought of this earlier!


Thanks to every one that gave me all of this great support!  I've learned a lot about how the coin comparator works and have also learned how many highly knowledgable people there are in these forums!  I couldn't have done this without everyone's support.


Much appreciated!    [size=78%] [/size]

[rickhunter]

Awesome!  I went ahead and powered up my 550 converted to NXT to note the behavior of the comparitor during the diagnostic.  It is indeed disabled when you first enter the diagnostic, and the led on the comparitor is orange (Red/yellow).  When enabled on the test menu, the comparitor light turns greens and it diverts the coins to the hopper.

You should go ahead and test the other MC40 you have to verify functionality.

[rokgpsman]

Well I am happy report that my coin comparator is now working!
.....
Much appreciated!   

Good job sticking with it!   

And a big    for your honesty on what you found. We've all had to retrace our steps at one time or another to find something we missed.

[fmetz374]

I just swapped out MC-40 and installed the original with the CMI # that ended in 200.  (the non WMS sticker MC-40)


That one does not work and I can never get the LED to go green.  It looks like for the WMS 550/NXT board combination you do indeed need the WMS approved coin comparator. 


Thanks again goes to Ros at CVSLOTS for getting me what I needed.   

[fmetz374]

One final question for the experts.  My connector is still "iffy" at best.  What is the actual/proper type of connector that I need for the 7-pin power and IO connector on the MC-40?


Thank you.

[rickhunter]

You could just cut off the wires and reconnect them using molex mini-fit Jr connectors.  It would only be the 6 wires, so not a whole lot of work.  When I did my conversion, I didn't have the tools to terminate molex ends, now I do, so if I were doing it today, I would just use that.  Since my cable has never given me any issues, I've just left it alone, but if it ever does I will just put molex ends on it and be done with it.