Thus spake Ed Todd (edtodd@SNI.NET):

> I did some experiments with PICMaster 16C65 pod J and noticed something
> strange.  When working with a PC, the signals going in both directions
> needs to be inverted.  For example, the 'rest' state of the PIC RX/TX data

Correct, and this is normally done by the RS232 driver chip. IF you check out
a MAX232 (or the older 1488 and 1489 parts) you will find that all the drivers
and receivers are inverters - the TTL levels coming out of the UART or whatever
are inverted through the RS232 driver.

Since the PIC is intended to be used with a driver chip, it has the standard
TTL levels in and out. You have to do the inversion yourself (but consider using
a MAX202 anyway - it's simpler and better, and not very expensive).

--
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clyde@htsoft.com      | P.O. Box 103, Alderley, | Fax:   +61 7 3354 2422
http://www.htsoft.com | QLD, 4051, AUSTRALIA.   |
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