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Old 2nd Jan 2018, 7:29 pm   #20
Sean Williams
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Join Date: Feb 2005
Location: St.Ippolyts, Hitchin, Hertfordshire QRA IO91UW
Posts: 3,517
Default Re: 8085 processor questions

A little progress update.

A replacement 8085 appeared in the post today, so I slotted it in - result..... Well, the green CPU led is now working, and the clock is running, and producing a T9 note as well

There is another oscillator on the card behind that wasnt wiggling at all, this was traced to a dead 74S04 - I only has 74LS04 in stock, so tried one of those instead - the oscillator is now also running.

Still nowt but rubbish on the screen though, so I guess next stop will be logic probe and see what the address lines are doing.

Thanks for all the helpful comments so far though.

Sean
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