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CPU Board Debugging - White Screen

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sigma7:
If the timing logic looks to be working properly, then we're headed back to square 1 to investigate what is currently happening.

Suggestions:

After you press reset, does /BERR do any cycling?

If /BERR cycles:

* does it continue cycling perpetually, or stop until reset again?
* (and) disable the bus timeout and probe the 68k address lines to find out what address is causing the first bus error after reset.

If /BERR doesn't cycle, does /AS cycle perpetually?

If /AS cycles:

* check that the EPROM output enables are cycling (U13D-22 and U14D-22)
* check /DTACK is cycling
If /AS does not cycle, check /RESET, /HALT, /BR, /BERR at the 68k.

edit for future cases: also check CLK at the 68K is about 5 MHz, as without a running clock, nothing is likely to work.

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