15 Oct
2012
15 Oct
'12
4:34 p.m.
> The analog input adapter (joystick interface) was
offered at the time of
> release, but no joysticks (until YEARS later) - but the docs had a drawing
> that was clearly and obviously the joystick of the RS Coco.
On Mon, 15 Oct 2012, Tony Duell wrote:
Which wouldn't ahve wored without intenral wiring
changes (not just a
conencotr adapter). The CoCo jopsticks used 3-terminal pots as a
potential divider acorss the 5V supply, the slider goes ot ta voltage ADC
input on the CoCo. The IBM (and Apple ][) joysticks are variable
resistors (2 terminal) used as part of the timing network on a 555
monostable (actually a 558, which is a quad 555, wired in monostable mode
only).
You would ahve to separate the 'bottom end' of the 2 pots in the joystick
for it to work proeperly.
Doing so took less time than changing the connector on them to a DA15.
Of coruse it's entirely possible that IBM were
planning on selling
joysticks made by the same company that made the CoCo ones, but wired fro
the 5150 adapter.
a reasonable guess