27 Nov
2007
27 Nov
'07
7:40 p.m.
Ensor wrote:
OTOH At the company I worked for at the time, the
beige "wedge shaped"
PSUs were dropping like flies - we found them to be HORRENDOUSLY
unreliable, and those were stock unmodified C64s too!
pics? I'm not sure I
recall a wedge-shaped PSU.
The 400 and 800 used a PIA (6520/6820) with 4 bits of
each port going
to each joystick port. The paddle inputs (analogue in) and triggers
were handled by POKEY.
Was the trigger IO, or just input?
Paddle inputs were likewise handled by 6560/61 VIC-I in the VIC, and
6567/69 VIC-II in the C64. Input only for obvious reasons.
If Atari only had 4 bits per port, You could still do 8 nybbles (4
bytes) of data and a SELect, or 2 bytes and SEL and CLK lines with both
ports across the two machines. What about TI or Apple?
Jim
--
Jim Brain, Brain Innovations (X)
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Dabbling in WWW, Embedded Systems, Old CBM computers, and Good Times!
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