Help! TI545 serial communication


Thread Starter


Cannot communicate with TI545PLC using new computer (Celeron 1G) under TISoft as well as Aimax (MMI software). The computer is fine. I can use it with Omron PLC on other machine.

The message is <communication time out> under Win98 and <communication error> under DOS. Can anybody tell me what is wrong. Your help is very much appreciated.

Barry Sinagra

We had this problem with win98 on older p266 machines we had to go back to dos mode(actual dos 6.22 or older) in order to resolve the issue.Also on some machines we were able to get tiSoft to work under win95. So far we have found that the windows version Softshop works under all windows based products. We had it working fine on a PIII 1.0ghz macine without any problems. I would suggest that you upgrade to Softshop as this is a windows based product and you have acsess to a far greater range of options.

This problem seems to do with the way Windows 98 handles serial ports. If you upgrade your PC to Win2000, the problem is solved!

Or else reboot the machine every time you want to go online to TI545 and select "Command Prompt Only' option from setup menu. (Not Dos Mode)

The problem with this is that you can't multi-task on PC while online to TI545 and it becomes a pain..

Zeljko Fucek

I've been using TISOFT with Win95/Win98SE/Win2000 over serial port with no problems at all, including multitasking (Excel, Word, etc.) - but just don't go overboard!

There is a README.TXT file included with the TISOFT (starting version 6.x) that explains how to setup the TISOFT shortcut on Win95/98SE desktop. I was following that and didn't have any problems on all three computers I used (two notebooks - Hyperdata & IBM A20m, and one clone PC). On one ocasion, I even tried TISOFT on Win2000, and it worked, I got it to communicate with PLC over serial link.

I am the one who raised the question. Thank you very much for your answers. The problem is not only TISoft but also Aimax cannot communicate using new computer. I have now reverted back to old computer P166 and is running fine under win98. My question is that whether new generation of computers treat serial port differently? If so what could I do a few years down the road when I cannot find old computers.

The problem is caused by the Windows 98 power management subsystem deactivating the serial port, when restarting in MS-DOS mode, and a DOS based driver's inability to "wake or reactivate" the serial port. The issue only occurs on sustems that have an ACPI BIOS and Windows '98. To work around this issue, make the following registry modification.
WARNING: Using the Registry Editor incorrectly can cause serious problems that may require you to reinstall your operating system. Toshiba cannot guarantee that problems resulting from the incorrect use of the Registry Editor can be solved. Use the Registry Editor at your own risk. For information about how to edit the registry, view the "Changing Keys And Values" Help topic in Registry Editor (Regedit.exe) or the "Add and Delete Information in the Registry" and "Edit Registry Data" Help topics in Regedt32.exe.NOTE: You should back up the registry before you edit it. 1. Boot into Windows 98.2. Go to the "START" menu, click on "RUN".3. Enter "REGEDIT.EXE" and click on "OK" to continue.4. Go to the following registry key: "Hkey_Local_Machine\System\CurrentControlSet\Services\VxD\VCOMM"5. Change the value of the "EnablePowerManagement" key from "01 00 00 00" to "00 00 00 00".6. Exit registry and restart system.By making this change, the computer's COM port power management is disabled.
It works. Thank you very much. I have been asking around about this problem for sometime already.
Let me express my sincere thanks.