Dead PET4032

tony duell ard at
Mon Oct 5 13:52:40 CDT 2015

> Look for inconsistencies in voltages and pulses to and from RAM.  You may
> need RAM at the lowest memory locations to boot.  Hooking up the keyboard
> at least to eliminate a missing keyboard as a reason the system does not

The PET keyboard is just a matrix of switches, if nothing it pressed it tests as
an open-circuit between all pins. So the machine can't fail to start up because
the keyboard is not connected.


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