Testing chips in circuit with an Oscilloscope

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Steve Rieck

New Tinkerer
Mar 24, 2023
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(for idiots perhaps...). I've got a Simasimac reloaded SE/30 board and I suspect the GLU chip is at fault. It cleaned up well but was kinda rough when I got it off the bombed board.

I have checked all pin continuity several times and everything checks out to destinations. No bridges also. Assuming that side of things is good, what would you specifically be looking for with the Oscilloscope to see if the GLU was alive and functioning correctly?

Walking the ROM bus? How is this done? Are there other aspects of the GLU that can be checked? Sorry I'm new to this side of things.

Thank you very much for any help!