Simple Command-Line Test for Roland MODELA MDX-15/20 COM port Connection

cover image Test Connection with Command Prompt (CMD)

I have used Roland MODELA MDX-15/20, a desktop CNC milling machine, for several years. Recently, I received an inquiry from the internet about the troubleshooting of these models. Here it is one of the test procedures for you to address the machine problem.

The story is that a newbie didn’t know why his second-hand machine didn’t work after he has received from someone else. Since those CNC models are a little bit old, they use RS232 serial (COM) communication rather than a modern USB port. The official driver defines the CNC machine as a general printer and makes use of Windows printer spooler for the connection. This old-fashion connection is easily causing trouble, especially when you use a USB-to-COM port adapter.

Moreover, printer settings are necessary to be configured correctly in their controlling software. To isolate the operating error, I suggest you to avoid using the official software installed. Indeed, you can test the connection between your PC and the machine without installing any software. You can ping the machine through a Command Prompt in Windows to inspect the serial port connection.

Here is the suggested test procedure.

Step 1:

Download my test file named “testmill.prn”, and copy it to C: (the root directory in your Windows computer).

It contains the codes of a small milling operation that can successfully run on my MDX-20.

Step 2: Prepare Your MDX-15/20

  • Check if the cables are correctly connected
  • Turn on your MDX-15/20
  • Press View button to exit the View mode

Step 3: Test From the Command-line

  • Open Windows Command Prompt (CMD)
  • enter cd c: to change the current directory to the root of your C drive.
  • enter type testmill.prn > com1 to send the machining commands to your MDX-20. (Change the COM port number if your machine is connecting to another port)
Screenshot of windows CMD for sending code via a serial port to roland mdx-15/20
Screenshot of Windows CMD for sending code via a serial port to Roland MDX-15/20

You should see your CNC machine moves if the connection has been set up correctly.

If you have any issues about the machine, you can visit our page FAQ for Roland Modela MDX-20 to find more solutions or leave your questions in the comment section of the FAQ page.

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