(Topic ID: 268471)

System 6 MPU troubleshooting with test rom, both LEDs on

By MeEtc

3 years ago


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  • Latest reply 3 years ago by zacaj
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    #2 3 years ago

    You only need the buffer chips if you're using masked roms. It's probably shorted internally which is why you're getting it grounded.... remove the buffer chips and go really bare bones, board without any ram/rom in it will just count up through all address pins. See if you get that, you'll know the cpu is booting then.

    also if it happens to be an AMI branded cpu, try replacing it as well.

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