Lite5200 from RS232 to RS485

[saurosalomoni]

Hello.

I need to switch between RS232 and RS485 in my Lite5200,
 but I realized it's a little bit more dificult than I
thought at first...
Well,  as far as I'm concerned, I can do that just by
controling the RTS pin of my ttyS0 device to activate
the 485 module (is it 100% right?).

I began trying to control it with TIOCMGET/TIOCMSET
ioctl(),  but the driver does not support hardware
handshake.. (tahnx,  Denk)
So now I think I'll have to write a small driver that
uses GPIO to handle the proper PSC register.

MPC5200 Users Manual states that you can set/clear the
RTS pin with bit 7 of the OutputPort 0 (op0, offset 0x3C).

My questions:
- Is this information I gathered correct?..
- Which PSC register I need to use to control ttyS0?
- If it's easyer to do it by extending an existing
driver, wich file should I look for?
- Is there any other way to accomplish that?

Thanks in advance.


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