Max485 & RS232

[rwskinner]

I tried it for grins.

Max232 tied to RB2 & RB5
Max485 tied to RB2 & RB5 with RB4 as the Enable on the 485 chip.

What I would really like, is both chips be driven the same, so I could use 232 or 485 without jumpers or SW changes. The end user could plug into either one but not both.

I'm not sure if there is any electrical issues with both tranceivers on the same logic lines.

Maybe safer just to include two 3 pin jumpers on RB2 and RB5 and let them select which one they want.

[Archangel]

I tried it for grins.

Max232 tied to RB2 & RB5
Max485 tied to RB2 & RB5 with RB4 as the Enable on the 485 chip.

What I would really like, is both chips be driven the same, so I could use 232 or 485 without jumpers or SW changes. The end user could plug into either one but not both.

I'm not sure if there is any electrical issues with both tranceivers on the same logic lines.

Maybe safer just to include two 3 pin jumpers on RB2 and RB5 and let them select which one they want.

Hello rwskinner,
How about using 1n914 diodes as isolation, the 07v voltage drop is not likely to kill off the signal, I doubt you really need anything but you could put a couple of gates in also.
regards,
JS