Can't get serial output on Digi Connect ME proto board

Hi all,

I am working on a multi-door security system using the Digi Connect ME. I have multiple doors on a private lan connecting to a common listening daemon on a server. The idea is that people will enter a code into a keypad on the door, an embedded board with an MSP430 will transmit the data via serial port to the ME which will forward it on to the server. If the server decides the code is valid, it will send a request to the ME to open the door. Got all that :slight_smile:

Now enter the problems:
I have succeeded in writing a small daemon to run on the server that accepts connections and writes some data back to the socket. I have also configured all the communication data on the ME. If I write to the serial port on the proto board I get the data on the server daemon no problem, however when I write data back to the socket, it never exits the serial port on the proto board. TcpDump shows that my reply data is indeed leaving the server bound for the MEโ€™s ip and the port the ME used to send the data to the server, but it never shows up on the serial port. Is something wrong or do I have a fundamental misunderstanding of the ME?

I also though that I might have to send the data to the TCP server on port 2101, but it doesnโ€™t forward that data out the serial port either. It appears that if a connection is open on 2101, the data that comes in the serial port is forwarded to that connect, but if there is no connection on 2101 it opens a connection per your autoconnect settings, correct?

One other question. Is it possible to change the destination ip serially? One of the competitors allows you to serially program the device with dst ip, dst port, etc.

Thanks a lot,


Hello Bary,

A couple of things come to mind:

First and foremost, What version of the Connect ME do you have? The Hardware revision โ€œKโ€ has a known combination of Firmware and Post that can cause behavior like this. If you upgrade to the Current version, this will be resolved. Current firmware is available here:

Other Possibilities:

  1. The Port Profile on the Connect ME is not properly set for TCP client.
  2. The Integration Board serial port is not properly set up, improper handshaking, or flow control.
  3. Possible cabling problems between the Integration board and the device connected to it.

From your e-mail here, I would expect this to be the Rev. K problem. If it is not this, I suggest using our On-Line submission form to build a Tech Support case.


You were correct. It was a revision โ€œKโ€, and upgrading the firmware fixed it. Thanks!


Glad I could help!