Re: Commodore joystick ports

From: Jim Brain (brain_at_jbrain.com)
Date: 2007-04-09 04:15:13

Scott McDonnell wrote:
> Of the 512 clock cycles, the first 256 cylces are used to completely
> discharge the cap. The second 256 are used to count the time it takes
> for the cap to charge to 50% of VCC (or 2.5V)
>   
As my results show, I think it's 2.0v and the 256 cycles are not needed 
to discharge the cap.  It discharges in at most 2uS after being clamped 
to 0volts (which makes sense, the shortest RC time would be when there 
is no R.

Jim

-- 
Jim Brain, Brain Innovations                                      (X)
brain@jbrain.com 
Dabbling in WWW, Embedded Systems, Old CBM computers, and Good Times! 
Home: http://www.jbrain.com

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