Re: COMM failed status of Fire Alarm 8000 series

["albertleng" <albertleng@xxxxxxxxx>]

Hi AJ...

There are only 3 pins in the serial interface of fire alarm panel, ie
Tx, Rx and Gnd. Fyi, Rx is actually not working also because the Fire
Alarm doesnt receive signals from outside.
A.J. wrote:
> Un needed overhead and you are not really monitoring for the disconnection
> at the fire panel side. I still believe it is better to monitor the DTR out
> at the fire alarm control panel with the PC's DSR IN.
>
>
>
>
>
> "albertleng" <albertleng@xxxxxxxxx> wrote in message
> news:1157956989.325276.309770@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
> > Hi Friends,
> >
> > I think i have found a way to solve it.
> >
> > Since the Fire Alarm cant receive from my PC (it only sends to my PC),
> > i use Tx of RS232 of my PC side and short it to pin 8, CTS. Then, i use
> > a timer to trigger MSComm1.Output in which Tx will send something to
> > CTS.
> >
> > If we disconnect the connector to the PC, the Tx and CTS are not
> > shorted anymore and there's no more sending from Tx to CTS.
> >
> > Albert