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Re: Apple //c displays black and white stripes



On Apr 27, 10:44 am, "Matt J. McCullar" <mccul...@flash.net> wrote:
> The Apple //c has a built-in self test.

True except for the original 16KB ROM (ROM 255) which does not have
the space.

> Try holding down these keys on the keyboard:
> Open Apple -- Close Apple -- Control -- Esc

I don't recall needing to press ESC and you have to reset the machine
so I would press Ctrl+Open Apple+Closed Apple+Reset and then release
either Ctrl or Reset (keep the Apple keys depressed until the self-
test starts).

Of course if the main RAM is faulty the system may not even be able to
run the self-test (the 2nd instruction after a RESET is a JSR so the
stack needs to work if the rest of the reset code is to function).