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rjhelms / compe6502

Homebrew 6502 system
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VIA I/O Card: occasional erroneous cassette input #9

Open rjhelms opened 2 years ago

rjhelms commented 2 years ago

Under some unknown circumstance, cassette input 0 can momentarily be received as a 1:

SDS00003

This seems to not occur when a scope probe is attached to pin 3 (Q7) of U6 - perhaps it is ringing on that signal which could be resolved by a small (30pF-ish?) capacitor.

rjhelms commented 2 years ago

Seems to be resolved by bodging on a 47pF capacitor between pin 3 of U6 and ground

rjhelms commented 2 years ago

47pF cap has seemingly fully resolved this. Need to check if this is reflected in the KiCad project.