Re: TI-H: TI-MOUSE


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Re: TI-H: TI-MOUSE



Jussi Vainionpää wrote:
>         Well, I connecting a pc-mouse to ti should be quite trivial. All you
>         would have to do would be converting the RS232 voltage levels to ttl.
>         Or if you used a bus-mouse you wouldn't have to do even that.

"All you would have to do"..? Okay, it's easy to convert the voltage
levels with a MAX232 but the software part is a lot trickier. Most mice
use 1200 bps and you would have to get the timing right from the TI's
end. You can't use the clock interrupt because it's too slow, about 200
Hz.

The only practical solution would be to connect a UART to the TI and use
it to time the RS232C operations right. In fact, that's what I'm
currently trying to build (as one of my projects...oh well.) I should
get the SCC2691 UART tomorrow and connect it to the TI with two
PCF8574's. Also, a MAX232 will be needed. With that design it is
possible to connect a mouse, or any other RS232C device such as a modem,
to the link port. But it costs about $30 (I'd guess, FIM 150 if you're
interested) to build.

-Ozone

-- 
*** Osma Suominen *** ozone@clinet.fi *** http://www.clinet.fi/~ozone
***


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