All you have to do from your PC software is to let for example the DSR high.
Then you can use a simple resistor or a 7805 to power your PIC and the
MAX232.
You should also calculate the maximun current you can spill from your RS232
port.

Take a look on the Microchip Application notes for interfacing a 16C54 via
RS232 (you should make some changes to make it work on a 16c84).

Good luck,
Raffaele


-----Original Message-----
From: Juan Leni [mailto:jleni@IMPSAT1.COM.AR]
Sent: Wednesday, May 12, 1999 10:49 PM
To: PICLIST@MITVMA.MIT.EDU
Subject: RS232 & power


I'm looking for some information related to powering an 16c84 from the rs232
port and at the same time having at least a half duplex communication.
I appreciate any information or idea.
Thanks in advance