Comms Problem with syswin on laptop

[kwhy 0]

Hi all I'm trying to connect to an Omron plc CPM1A with a old toshiba laptop 4600 through its com1 ( Syswin 3.4 on Win98) and getting 'connect failed' Using the same set up on a newer XP desktop works fine Tested the com1 port on Laptop by connecting a serial modem to it, works fine Help Kwhy

[Sleepy Wombat 27]

What are your comm's settings in Syswin...

[kwhy 0]

9600 , data bits =7 , Even and Stop = 2. Tried different baud rate and no luck. Same settings work on the other PC

[Sleepy Wombat 27]

Does the PLC comm;s light even flash when you try and connect.... Typically it will flash around 3 times while it trys to communicate to the PLC... if it aint flashing then there would apprear to be a problem with the comm;s getting through... 1. Could be that an application has hold of the comm;s port 2. A programming cable problem 3. A broken cable 4. Problem with the CIF01 5. Problem with that PLC's comm's port.

[kwhy 0]

Yep, light flashes while its trying to connect. Like i said the same cable and plc works on a different pc . It has to be the laptop. But what !

[Sleepy Wombat 27]

Ok, so you have proved the comm;s to the PLC... but it sounds like Syswin aint getting a response back. When you tested the modem where you getting your characters echo'd back ?

[kwhy 0]

Used a wire jumper to connect pin 2 to pin 3. And With hyperterminal any text type was echoed on the screen. Like you said it must be syswin not talking properly to com1

[PdL 71]

If using a CIF01 RS232C adapter, is the mode switch setting on the CIF01 set to "host" ?

[kwhy 0]

Yes the adaptor is set to Host

[Sleepy Wombat 27]

Have you check if any resident programs are nabbing the port ?

[moosty 0]

That is a good way to test com port. However, it may not be enough sometimes. Shorting 2 and 3 only tests Rx and Tx. If some other pins required for hardware handshake are burnt and you are trying to communicate by 'Hardware Handshake' , you may not be able to communicate. Try without an handshake