[Coco] Joystick jitter in OS9

CoCoList for Color Computer Enthusiasts coco at maltedmedia.com
Mon May 12 23:08:09 EDT 2014


On Monday 12 May 2014 22:18:42 CoCoList for Color Computer Enthusiasts did 
opine
And Gene did reply:
> The hires joystick has always had this jitters problem. Software can
> try and minimize it but it is inherently jittery.
> 
> The jitter is from noisy potentiometers (due to age), electrical
> interference picked up by the cord to the computer and software
> drivers not running as efficiently to minimize the problem.
> 
> What we ideally need is a digital interface rather than the current
> analogue system being employed.
> 
> May I suggest to try and design your program interface to use keyboard
> commands (1-9, F1 & F2, first letter of command etc)...unless someone
> can design a new and more reliable mouse interface.
> 
> Nick

The true serial mouse, using a set of piggy backed chips in an RS-232 
pack, is absolutely dead stable.  Been using it for about 15 years. 
Recognizes all 3 buttons of either a logitech or an M$ style mouse, auto 
switching when it detects the first packet that is not used in the default 
configuration.

For Nitros9 only, try the joydrv_6551L.sb module in your boot instead of 
the normal mouse driver.  But read the src code to see where its 
addressed, ISTR its in the 4 byte wide block above the /t2 port.

Its been so long since I hacked up my 232 pack that I've long forgotten 
exactly what I did.  Base port address is ff6c-6F, so if your extra chips 
are decoded at $ff6c, it should Just Work(TM).  If not, send details.

Cheers, Gene
-- 
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Genes Web page <http://geneslinuxbox.net:6309/gene>
US V Castleman, SCOTUS, Mar 2014 is grounds for Impeaching SCOTUS



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