How long distance for RS232 ?

[iugmoh]

Hi all
I use MAX232 or DS275 with PIC16f877A to make serial communication, anyone know how long distance for this communication ??

[mat janssen]

For rs 232c communication is 1200 m max.
If you change it to rs422 or rs485 then a few Km more is no problem.

[mackrackit]

For rs 232c communication is 1200 m max.

In real life with RS232 you can expect around 100 feet (30 meters).
I am talking a reliable setup with good shielded cable and the environment used in does not have great amount of noise (electrical).

[Charles Linquis]

It depends a lot on the cable and the baud rate. Many years ago, I ran 115Kbaud through 100' and 19.2Kbaud through 300' of expensive shielded cable. It was for PC network that ran through serial ports instead of Ethernet.

[iugmoh]

Thanks for your replies

I think that RS485 will be a good choice for long distance as I read in some sites

[Ioannis]

What is your definition for long?

Ioannis