serial port to communicate with an S7-200 PLC


Thread Starter


I've just bought a second-hand Dell Latitute notebook(266MMX). But I can use it's COM port to communicate with an S7-200 PLC. How can I do

P.S.: I usua use my desktop PC to communicate with PLC. It's OK. But I can do that with my notebook. Please show me how to do now!! Help me!

Hakan Ozevin

Please Check if the COM port you are using is 1) visible by Windows, 2) functioning (e.g. by using an external modem or printer with serial

Kerry Sparks

I assume you're trying to use the same software on both your desktop and the notebook, and that the problem is that the COM1 port on the Latitude is not set up correctly. I would suggest going into the BIOS (F2 - Setup at power up) and
making sure the COM1 is set for serial and NOT set up as the IR port (my Latitude has COM3 set for IR). Next make sure once you're booted up to the Windows OS (you didn't mention which Windows operating system you're using) and make sure you're not using the IRQ for something else, like a Model. Troubleshooting serial problems on PC's is something I've had lots of experience with since our company has a software package that transfers files to an operator interface from the PC's serial port. Depending on whether you're
running Win98, NT, or 2K you will have different tools through Control Panel or Administrative Tools to troubleshoot device conflicts. My Dell runs Windows 2000, and the tool to use there is accessed using the System icon in Control Panel. Go to the Hardware tab and use "Device Manager" to look at all the hardware devices. It will show you if there are any device conflicts and it will show what resources are being used by each device. There is even a built in "Troubleshooter..." wizard that help you clear up the conflict (Windows 95/98 has a similar tool). If you've got Windows NT it's a little trickier but you can start with "NT Diagnostics" under "Start>Programs>Administrative Tools (Common)" and look for resource conflicts. Good luck!

Zan Von Flue

To use the Microwin with the S7-200 through the Com-port you need a RS232/PPI convertor.
Does your PC have a comunication card (ISA or PCI) or maybe the convertor is connected on the com port on your PC.