Dotmation Screen Message

[dale]

I started up my WMS 400 game today and was greeted with a machine that does not work. I am getting a BAD PACKET TYPE message on the Dotmation screen. The game just keeps going from Dot Init , one bong and repeating itself. Any help is appreciated.

The game will occasionally work. Whenever I push the BET ONE button the game tilts again. It will tilt on the MAX BET button but not as often.

I am actually getting 3 bongs between the cycles. Could that be a bad XU31?

Now it will play with the MAX BET button. It will not play and go into its tilt mode when I push the BET ONE button. I changed out the button harness with no difference. I'm thinking chips or CPU board. I haven't tried a clear yet as not sure that will solve this. Help!

[knagl]

With the power off, I'd check the communication cables between the Dotmation box and the machine (unplug and re-plug the cables to make sure they're seated nicely and to help wipe off any oxidation that may be starting in the plug/harness).  If that doesn't make a difference, the next thing I'd try (with the power off again) is to pull and re-seat each of the game and Dotmation chips (for the same purpose).

A "Packet" in computer speak is a small blip of communication from one point to another -- that's what makes me think that it's a communication issue between the main boards and the Dotmation box.

[dale]

I changed the Serial Port harness from the controller board to the backplane, the cable between the dot box and controller board, the Dot Box itself, reseated all the chips and put a new controller board in. It will initialize then buzz and bong, spin slowly, show credits then display goes blank and it repeats itself again. The Dot box will show half the screen then sits on Williams. Any other part I should look at? Thanks.

I just put a new game in. I changed the controller board with chips and the CPU  board with chips. I left the IO board in because the jurisdiction is the same. The game went right up.

I think we are narrowing it down to CPU board or corrupted chips.

I just switched out CPU boards. Game is working fine right now. I have my fingers crossed. Thanks for helping.

[knagl]

You're doing some good troubleshooting. 

Chips generally don't tend to go bad, but I suppose anything is possible.

If I'm reading correctly, you have multiple boards, right?  If so, use the known good boards that are in there now and put the chips in question into those boards.  If the game clears and then works properly from there, your chips should be fine.  To further troubleshoot, replace one board at a time with questionable boards until you run into the issue.

[dale]

I did as suggested. The game is up and running. The CPU board apparently took a dump. I am hoping it stays working.Thanks for all the help.

[knagl]

You did most of it yourself!  Nice work.

(To save yourself a headache later, you may want to label the suspect board as "Bad?" with a post-it note or something, but if nothing else keep it around for future repair and/or to steal components off of in the future should you need them.)