How disable attachment of sio(4) driver to device?

[Daniel O'Connor]

On Sat, 22 Oct 2005 06:09, Bernd Walter wrote:
> I personally build specialized USB and Ethernet devices for doing
> Modbus/RTU RS485 timing.

We use 9 bit data RS485 (the ninth bit is used as an address mark so 
microcontrollers can sleep until it turns up then check if it's addressed to 
it and go back to sleep).

I have been told it could be implemented as a line discipline but I am not so 
sure (since to do 9 bit transmition you need to change between mark & space 
parity on a byte by byte basis)

We (well msmith originally) implemented it as a cut down hacked up copy of sio 
- this IS suboptimial so I think I'll have a look at implementing it via 
uart.

-- 
Daniel O'Connor software and network engineer
for Genesis Software - http://www.gsoft.com.au
"The nice thing about standards is that there
are so many of them to choose from."
  -- Andrew Tanenbaum
GPG Fingerprint - 5596 B766 97C0 0E94 4347 295E E593 DC20 7B3F CE8C
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