MMS3000 will not Communicate with MAS Software. I can't get my MMS or VB to communicate with its MAS software. What should I try?

Submitted by glx25v on Fri, 08/17/2018 - 17:29


  1. Ensure that the MMS or VB battery has at least 30% charge.
  2. Ensure that your PC has at least one free COM port. For example, if your PC has two, but one is used for the mouse and the other is used internally to drive a modem, then you have none free! You should purchase and install a Serial Port Card in your PC. They are cheap and available at all computer stores.
  3. Check that Windows has detected the ports, and it reports that each one is 'working properly' and has 'no conflicts'. This should be checked in the Control Panel >> System, under the Device Manager (each version of windows is slightly different).
  4. Connect the unit via its cable to a free COM port on your PC, and turn it on. If using a VB, in MAS VB use the automatic detection under Options >> Configure Comm Ports. If using an MMS or Profiler, in MAS under Tools >> Configure COM Port, set the baud rate to automatic and use the 'Test Port' button for all of the available ports.
  5. Repeat the above for all free COM ports.
  6. Ensure that no software protection dongles are connected to the COM port you are using.
  7. If there is still no communication, there may be a problem with your cable. First identify which type of cable you have, of the two which have been produced. One has a screw ring to lock the connector at the MMS/VB end, the other has a little push button.

    Then use a multimeter to check the continuity of the following lines:
    DB9 (PC) Connector Screw-ring lock connector Button lock connector
    2 3 1
    3 2 2
    5 1 5
    8 5 3

    Then use the multimeter to check the insulation at the DB9 connector:
    Check between every pin and pin 5 (signal ground), there should be no connection. Check all pins, not just those in the table above. Flex the cable while performing the test.


  8. The screw-ring connectors are prone to becoming loose after a lot of use, and making intermittent contact. Look at the contacts, for any obvious corrosion or looseness.
  9. If possible, repeat the above steps using a different PC.
  10. If there is STILL no communication, then please send an email to Help detailing the problem, including at least the following information:
    • the type of your MMS or VB.
    • the version of firmware it is running (this should be displayed on the screen at power up).
    • the version of MAS software you have.
    • the type of PC you are using.
    • which operating system it is using (e.g. Win 95, NT, ...).
    • how many COM ports does it have, and which ones are free.
    • which type of comms cable you have (screw lock or button lock).
    • whether you have been able to check the continuity of the cable or not.