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

[John R Pierce]

On 11/8/2014 1:55 PM, Jason Ricles wrote:
> I am not too sure, it is for work and we got a custom board. My co worker
> who is more the hardware guy set it up. I did notice it is thin before 3.0
> kernal. I saw in the 3.0 kernal they have more support. So we are basically
> up the creek without a paddle with the device and kernal 2.6. Would a
> RS-485 to RS-232 converter possibly fix the problems?

the problem is, a 232-485 converter needs to be told when to be in 
transmit vs recieve mode for a half duplex single pair circuit to 
function.  as that article says, this can be done by using the RS232 RTS 
signal to control the RS485 line driver, but the linux driver has to 
know about this and support it.



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