Messages in this thread | | | Date | Fri, 4 Aug 2000 15:05:55 +0100 | From | Roger Gammans <> | Subject | Re: Re hardware handshake support for 2.0/2.2/2.4 |
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On Fri, Aug 04, 2000 at 02:18:52PM +0100, Alan Cox wrote: > > I been asked to put togther some driver support for some of these cards > > and was thinking about an ioctl, but is there a std which overs this? > > For a radio modem I got involved with the RS485 was just done in userspace > via the modem control ioctls
There are different h/w arrangement for RS485 IIRC though, these cards give the folowing options:- Half-duplex auto-gated, Half-duplex RTS switch, tx when RTS high[1] Half-duplex RTS switch, tx when RTS low[1] Both Tx/Rx Disabled. Tx only Rx Only Full Duplex.
I guess you were using either option 2 or 3 with that.
These various modes are handled by the hardware and you can switch them just be setting the register approriately. Assuming kernel or CAP_SYS_RAWIO (is this the right one?).
TTFN
[1] Just to confuse matters one set of these cards then goes and uses DTR instead of RTS. -- Roger Think of the mess on the carpet. Sensible people do all their demon-summoning in the garage, which you can just hose down afterwards. -- damerell@chiark.greenend.org.uk
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