RE: Serial connection over Cat5 getting corrupted

["Paul Gale" <groups@xxxxxxxxxxxxxxxx>]

Thanks for the replies everyone :)

The power supply, baudrate etc are all fixed in the computer.

I haven't tried running Rx and Tx over twisted pairs though - I'm not sure
=
which wires they're running on but I have a feeling they won't be on a
pair=
! I'll try that first.

Thanks!

Paul.

> -----Original Message-----
> From: ukha_d@xxxxxxx [mailto:ukha_d@xxxxxxx] On Behalf Of
> David Yeend
> Sent: 13 July 2005 23:44
> To: ukha_d@xxxxxxx
> Subject: Re: [ukha_d] Serial connection over Cat5 getting corrupted
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> Certainly pairing the TX and RX with a ground shows an improvement in
> my experience. I can only think this is due to minimisation of cross
> talk, RS-232 is single ended and not balanced so you do not get the
> same common mode 'noise immunity' as with a technology designed for
> twisted pair, such as Ethernet or RS-485.
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> I think it safe to assume that you already have the cat5 in place and
> want to use it - an alternative cable is probably least favourable. If
> 2 way comms is involved, status and control, and it is critical - i.e.
> you would like your fish to survive and loosing comms would reduce the
> likely hood of this, then I would not risk the possibility of 'just
> getting by' on cat5. In my opinion there are too many
> variables.....new sources of noise having unforeseen effects,
> degradation of the interface electronics leading to attenuated signal
> or jitter etc.
>=20
> My solution would be either purchase one of the MSS100s and have it
> talk to a virtual com port, or (being more sociable) purchase a pair
> and have them talk to each other and provide a physical RS-232 at Node
> 0. Alternatively use a pair of RS-232 to RS-485 converters and match
> the line technology to the wire in use.
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> Good luck.
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> David
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> On 7/13/05, Paul Gale <groups@xxxxxxx> wrote:
> > I've just wired up my aquarium computer (RS232) via my structured
Cat5
> cabling back to node0. I guess there's about 10-15m in the run.
> >
> > The trouble is, I'm getting some corruption in the sent data =96
spurio=
us
> characters and line feeds missed off.
> >
> > Any ideas what I can do to improve the comms?
> >
> > Ta,
> >
> > Paul.
> >
> >
> >
> >
> >
> > [Non-text portions of this message have been removed]
> >
> >
> >
> >
> > Yahoo! Groups Links
> >
> >
> >
> >
> >
> >
> >
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> Yahoo! Groups Links
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