As Ruud Baltissen once put it so eloquently:
> I run into a weird problems. It all has to do with my C64IDE project. After
> I told the IDE harddisk to start or stop its motor, most of the time my
> keyboard does not respond in the way I'm used. I see a normal flashing
> cursor but the moment I press a key, it starts to flash with an enormous
> speed but doesn't move and the typed char does not appear on the
> screen.
I'm pretty sure I've seen this behavior before, but I don't remember
what triggers it (software bug? It always seemed to happen when the
system was already acting strangely). Usually when I encountered it,
the cursor would start out flashing more slowly than normal. Then,
when you hit a key, the cursor would flash madly and only a few
keystrokes would show up (you had to repeatedly hit a key, and only 1
of 50 or so would register). It was as if the IRQ routine were
spending so much time flashing the cursor it couldn't actually do the
keyboard read (or the keyboard strobes were happening so fast the
keypress wouldn't register by the time the read happened).
This was on an NTSC C64. I saw it happen a few times over the years,
so not common.
> What I'm going to do now anyway is to add a routine that displays the
> contents of the CIA's before and after the action. Why didn't I do that
> before writing this email? I did but I run even in more troubles. And I just
Remember that reading some CIA registers changes them :)
%% Chris Bongaarts %% bong0004@tc.umn.edu %% http://umn.edu/~cab
%% Univ of Minnesota %% CBongo on EFnet IRC %% Stop Plate Tectonics!
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