serial motor stepper labview 5.1

[Shellpetal]

Hello

I am using LabVIEW 5.1 with Windows 98 and I'm trying to contol my stepper motor through the serial port. This version of LabVIEW has Serial_port_out.vi and not port_out.vi as in all the examples I have found.

My problem is that I don't want to send the device a string, but a byte, but this version won't let me do this. What can I do?

Thanks

[Dennis_Knutson]

You actually have two methods for writing to the serial port. There is the Serial Port Write function and on the VISA palette, you have VISA Write. If you ever plan to upgrade, using the VISA functions is recomended. The Serial Port Write depends on a driver called serpdrv and this is no longer supported. Using VISA now will make the migration less painful. No matter which one you choose, you can easily send a byte. On the string control/constant, you can right click and select Hex Display. You can use a U8 control/constant and typecast. You can use a U8 array and the Byte Array to String function.

[Shellpetal]

I have the serial write.vi connected and I have the correct port address, but there is no response. Is there anything I can use to walk me through this probably very simple task?
Thanks

[Dennis_Knutson]

One thing about the port numbering with this old function is that Com1 is port 0, Com2 is port 1, etc, so double check your setting. Other than that, I would recomend you check the communication with a different program such as hyperterminal. If hyperterminal doesn't work, you may have problem with the com settings or are using the wrong type of cable.