[CentOS] RS-485 over a half duplex serial in Centos 6.5

John R Pierce pierce at hogranch.com
Sat Nov 8 21:49:09 UTC 2014


On 11/8/2014 1:36 PM, Jason Ricles wrote:
> Hi, I am trying to make a program in C to communicate with a temperature
> sensor over my serial port that uses RS-485 and is a half duplex. I am
> however having trouble getting the device into RS-485 mode, is it possible
> to use RS-485 mode in Centos 6.5 or does it only support RS-232 mode?

standard legacy PC serial ports are strictly RS232C.    RS485 is a 120 
ohm balanced line specification.    What host-side serial port are you 
using that has RS485 support?

re: linux support, I found this: 
http://retis.sssup.it/~scordino/code/rs485.html      which suggests '485 
support is pretty thin in Linux.



-- 
john r pierce                                      37N 122W
somewhere on the middle of the left coast




More information about the CentOS mailing list