This program is used for testing devices connected to your serial port. You can send commands to the device and see what kind of response you get.
Setup the port by clicking Port / Port Setup. Set the parameters for your port.
Click Port / Open to connect to the port. If the light turns green then you are connected to the port. Remember that just because you can talk to the serial port, it doesn't mean that you are talking the the device that is connected to the serial port.
Type in the command you want to send to your device and see if you get a response.
Check the Use uppercase to guarantee all commands are sent as uppercase.
Send using CR will append a single carriage return to the line you typed else a linefeed is appended.
Use Ports / Clear old commands to remove all previously typed commands in the pulldown.
If you can't get a response then it is possible you are connected to the wrong connector on your computer. You may have the wrong kind of cable. You could be talking at the wrong baud rate. Some devices need to be programmed to accept commands from the serial port.
This program is available on an "as is basis". I make no claims that it will work on your system. Use it at your own risk. You are free to use it as you like but remember that I own the rights to it. See you on the web at www.llevine.com.