crap that didn't work its got to be something to do with the serail handshake
cause i can make the DCE side look the same as on the r486
rd and cts -VCD
dsr and dcd +VCD
any software tools you know of to trouble shoot handshaking?
Quoting tims <tims@timsworld.net>:
> RS-232 486 PC RTS is unasserted (off) while DTR is asserted. TD is just
> idle at the time you read the voltage.
> Pentium class RTS in asserted. Odd that this would prevent
> communications. I don't believe that the UART hardware has changed much
> since the 16550AF with the fixed FIFO, so I would assume here that this
> is a software issue. Can you force RTS off with your breakout box and
> then see if the PLC will talk to the pentium class computer.
>
> Try shunting RTS to CTS on the PC side of the connection for the pentium.
>
> The 486 should have RTS enabled as well - strange.
>
> rob wrote:
> > Hi Linux Friends!
> >
> > This is not Linux related really, I was wondering if anyone has had
> > problems like this.
> >
> > dos 486 cmputer serial port -> plc serial port
> >
> > td (-VDC) rts(-VDC) and dtr(VDC) as per my serial breakout box
> >
> > this one is recognized by the PLC as a serial port so it will accept
> > data
> >
> >
> > pentium class machine
> >
> > td (-VDC) rts(+VDC) and dtr(VDC) as per my serial breakout box
> >
> > this one is not recognized as a serial port and will not accept data?
> >
> > any idea on the changes in uart hardware over the ages? or is this
> > purley a software driver issue?
> >
> >
> > --
> > I'm interested in upgrading my 28.8 kilobaud internet connection to a
> > 1.5 megabit fiberoptic T1 line. Will you be able to provide an IP
> > router that's compatible with my token ring ethernet LAN configuration?
> >
> > To unsubscribe, send a message with the word "unsubscribe" (without the
> > quotes) in the body to linux-request@slg.org
> > Archives are at http://list.slg.org/
> >
>
>
> --
> I'm interested in upgrading my 28.8 kilobaud internet connection to a
> 1.5 megabit fiberoptic T1 line. Will you be able to provide an IP
> router that's compatible with my token ring ethernet LAN configuration?
>
> To unsubscribe, send a message with the word "unsubscribe" (without the
> quotes) in the body to linux-request@slg.org
> Archives are at http://list.slg.org/
>
Received on Wed Jul 30 15:34:20 2008
This archive was generated by hypermail 2.1.8 : Wed Jul 30 2008 - 15:34:23 CST