Writing pins to the RS232

[Peter Hansen]

Richard Brodie wrote:
> If you just need one or two signals, then it might be practical to use one
> of the control lines, and PySerial supports this (UPS monitoring software
> often works this way). Setting 8 pins to 1 would be impossible, because
> there plain won't be that number of outputs wired, in addition to all the
> good stuff about UARTs Roy said. 

All true, but then Jay might get into electrical compatibility issues, 
and may not realize that the output levels of RS-232 serial hardware are 
not simply 0 and 5V levels, but rather +9V (or so) and -9V (and with 
variations from 6V up to 13V seen in the wild), and without much in the 
way of drive capability.  Using this to control custom hardware would 
probably be an exercise in frustration and kind of pointless in 
comparison to using parallel hardware, which at least has more typical 
logic voltage levels.

-Peter