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markcadcam
- 31st May 2006, 18:13
Hi all,

I am working on a project that requires using (2) 18F452 micros communicating between themselves using Serin and Serout commands. I will be using 24 gauge-shielded wire for the communication connections. What is the recommended maximum length of wire between (2) micros?

Thanks,
Mark

Travin77
- 31st May 2006, 21:28
I have read that serial cables should not be longer than 100 feet. I have read 5 volt serial data at fifty feet with cat5e. Hope this helps.

travin

markcadcam
- 31st May 2006, 22:51
Thanks.

Mark

BobK
- 1st June 2006, 02:07
Hi Mark,

RS485 is easy to implement, pretty much like a serial port, and can go up to 4000 feet on a pair of wires. Do a search on this site for RS485 and also on Google and you should be overwhelmed with information. www.Parallax.com has a tutorial for using RS485 chips with the Basic Stamp which is a PIC chip in disguise.

BobK

markcadcam
- 1st June 2006, 11:51
I'll check it out. Thanks!

Mark

Melanie
- 1st June 2006, 12:25
Point-to-Point 2km for proper RS232 and that's without line extenders...

sayzer
- 1st June 2006, 13:07
Point-to-Point 2km for proper RS232 and that's without line extenders...


...and can go up to 4000 feet on a pair of wires...

Are you guys (and girls) saying that we can put 2000meters of RS232 cable between two PICs and expect them to see each other on the line?

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Melanie
- 1st June 2006, 14:29
At proper RS-232 levels (not at logic levels) yes. If you use unshielded CAT5 cable then a little less. If you want more, use a line extender.