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Old 14th Sep 2017, 11:02 pm   #19
PETERg0rsq
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Join Date: Jun 2009
Location: St Helens, Lancashire, UK.
Posts: 641
Default Re: Help with 6802 Microcontroller

The "range" LED will light if there is no clock.
The 10 MHz clock I guess is isolated via T2, divided by SN2 and level shifted by Q3/SN1. All looks OK, and I get a good "E" clock which is derived from the EXTAL input.

Anyway I seem to have a partial success

I hooked up the last few channels of my logic analyser to SN9/SN11 5V supply, ROM1 CE, ROM2 CE, ROM1/2 DE and the ROM 5V supply and

The signal generator boots up perfect every time, and doesn't lock up!

I will have to leave it for tonight, but tomorrow I will try and find out why connecting the logic analyser makes it work.

pods state 200 KΩ by 3 pF so will have little effect on the logic, but obviously enough to change the timings!

Will keep you informed of what I find.

Peter
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