RS232 pic <--> PC

[Louati]

Hello
I have a little problem with communication rs232, in fact when I do simulation with Proteus ISIS it's working but when I integrate the chip Max232, infomations are received but they are all false :(
Even in practice the same problem :/
I supposed that the max232 is not working so I integrated another pic and I used the Max232 to transfer informations from pic1 to pic2 and it's working !!

[gpsmikey]

Have you verified the voltage levels are correct on the max232 chip ? (the correct charge pump caps are in place). How are you trying to talk to it from the PC ? Hyperterminal or just what? What does a scope (if you have one available) show on the tx and rx lines to/from the pc ? Remember that RS232 is inverted, so a "1" from the PIC should be a negative voltage on the MAX232 chip.

mikey
_________________
mikey
-- you can't have too many gadgets or too much disk space !
old engineering saying: 1+1 = 3 for sufficiently large values of 1 or small values of 3

[Louati]

[Mike Walne]

Describe the problem you are seeing.

The CCS manual suggests several tests for RS232 links.

CCS also provide example programs which can be used with a PC to verify correct operation.

Mike

[temtronic]

You should also do a loopback test of your 'USB<-> RS-232' convertor. Not all actually work ! I have 2 new ones here both fail miserably.

Useless Serial Bus....sigh, bring back REAL comports!

[bkamen]

[Louati]

Actually it just a problem of inverting input and output
It's on right now Thanks for help