Quote Originally Posted by swr999 View Post
Of course you're right! Why didn't I think of that? ;-\
I'm just using a 3-wire connection, so I suppose, aside from a dedicated RS232 translator chip (MAX232 etc), I could use any scheme to hardware-invert the Rx and Tx lines?
Thanks for the helpful responses!
You can use any scheme to invert the signals and it will work, bearing in mind that you might encounter an interface that it won't work with because it doesn't strictly meet the spec. You'll have more success with a 5V PIC, and you should protect any input from overvoltage on whatever device you use. I do this all the time for one way communication out of the PIC for dumping status logs or other information that doesn't require a response from the computer. Typically, I use an N-channel FET to do the inversion, but a spare comparator or op-amp will do too.