Bagman board dead z80 reset stuck low

dyno

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Just picked upa untested bagman board hoping it was working but it wasn't, noticed that the reset on z80 stuck low, wr is dead and that there is nothing happening with the data lines or address lines. Swapped out z80 with another but no luck. Also pin 6 the clock is not pulsing.
 
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how is your crystal and reset circuits? Are you even getting 5 volts in there?

+1

You have to check the voltages, First. Second check the crystal to see if that is even doing anything, if yes then check all chips/traces coming from the crystal to near by chips. Check the voltages on the chips near the crystal also. With no clock it is like a car without a starter and you can't push start it.

Look for scratches and any damage to the board, I also hope that was not subjected to high voltage or ac voltage.

On the bright side, chances are good that when the clock is working that board will spring to life.
 
Also, does your power supply have a READY line? Some power supplys will hold not reset low for a few milliseconds for the power to stabilize.
 
Problem fixed, Bagman LIVES! A few sockets had been replaced and I found a broken trace at one of the pins on the socket and also the IC 74ls368 at A6 was bad swapped that out with one from my other none working bagman board and bingo it works now. I was hoping that once the clock started working that the board would come to life just like kb0jjn said, it did. Thanks for your help guys:)
 
Problem fixed, Bagman LIVES! A few sockets had been replaced and I found a broken trace at one of the pins on the socket and also the IC 74ls368 at A6 was bad swapped that out with one from my other none working bagman board and bingo it works now. I was hoping that once the clock started working that the board would come to life just like kb0jjn said, it did. Thanks for your help guys:)

There is no better felling for me when I help someone fix their own board.

The chance meeting with mclemore and his photographer at a second hand store in California was what got me here and it has been a life changing experience. For that I am very thankful!

I am glad I helped you get this board working and great job. I could not have done it without you.
 
I appreciate your help, it sure nice to have somewhere to go for help when it is needed. Still going to try and get my other bagman board up and running, still just scrolls through garbage when powered up.
 
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