Is there diffrent 3902 REV C , REV B

[ALIDMAN]

Hi everyone , so I thought 3902 is only one model that works in all game kings , here is what I have on my hand :  I have 2 of the 17 inch game king machines , one is working and one does not , I pulled everything including I/O cards from working machine and put them in non working machine , NO LUCK , disconnected the printer , NO LUCK , checked cherry switches , NO LUCK , moved the 3902 board from working machine with same software ( 4.3 ) to the non working machine , it will let me to clear it but when I turn the reset key several times and push the white reset button for 2-3 seconds , it comes up as CALL ATTENDENT .


so I have several different 3902 boards and I notice the numbers are different so is the mother boards , here comes $64 question : is there different 3902 boards that needs to match the mother boards , cause that's the only thing I see different , I always thought 3902 boards are all the same , any input would be very much appreciated and happy holidays everyone   

[wizeone]

the "call attendant" message is that in a big blue or black box?  sounds like the door might have been closed(or cherry pulled out)

[Tilt]

I agree.  Once the door is opened or the cherry switch pushed in it should change from CALL ATTENDANT to the actual error message (RAM ERROR, EPROM ERROR, ETC). 


All 3902 boards are basically the same, there may be different revs but they will work with any 3902 motherboard.  Once the game is initialized, setup, and running the EEPROM on the motherboard will contain information specific to that MPU board and the software installed on it.  Change either and you'll get some error messages, but by following the onscreen directions the EEPROM will get updated for the new MPU/software. 

[ALIDMAN]

Thanks for the response guys , I did check the cherry switches , that's why I was at point why this is not working , I will replace cherry switch also this weekend and see what happens , thanks for your input again and have happy holidays everyone