4 Replies Latest reply on Oct 15, 2014 7:14 AM by ignacio guerra

    Problem with IrDA on MC75A

    Juan Martinez Villena



      We tried to use the terminal to MC75A way communication through the port IRDA against a machine ( no windows ) . The purpose is not to transfer files, exchange information and keep a dialogue.


      We have the same application in other brands of terminals and functions properly.


      The problem is that if we send bytes on COM3 ( IRCOMM ) , the device sends data previously with your device name on it. With this operation, the machine does not respond correctly because there is a layer (we think ) that interacts before sending data .


      If we use the COM4 port ( RAW IR) , you get to write the information , but not read from the other device . The same code with another handheld with Windows Mobile 6 works fine. But if I use the same code on the MC75A , just write .

      We have developed two versions of the same program I'm using the SerialPort objects in VS.NET and using the port with CreateFile instead of SerialPort . However, the same result : sometimes we fail to read or write when the program is used version of CreateFile . Currently my code works with other devices, the Motorola MC75A reads and writes only 255 characters (ÿ).


      Does anyone know if you need to configure any component MC75A to use the infrared port as a clear standard serial port ?


      Thanks for your help

        • Re: Problem with IrDA on MC75A
          Pietro Francesco Maggi

          I have attached one sample application "COMPortTransceiver.exe" that I used times ago to make some tests on MC75A IrDA.

          Follow below steps to use the application.


          1. Uncheck the following settings Start-->Settings-->Connections-->Beam--> Beam Mode ("Receive all incoming beams").

          2. Copy the "COMPortTransceiver.exe" into 'Application' folder of MC75A device having latest BSP image.

          3. Tap the Application to launch it.

          4.  Tap on 'Configure' tab.  Do the following settings,

              Port=COM4; Baud Rate= Set desired baud rate by using up/down arrow keys. Data Size=8 bits, Parity=None,

              Stop bit=1 bit, Flow Control=None, Check the 'InfraRed' box. Click 'OK'.

          5. Tap on 'Open' tab to open the com port.

          6. Do same settings on another MC75A device which will be paired with the first one.

          7. Align the IR transceivers of both the devices to make it line of sight.

          8. Now tap on 'Write' tab of one device couple of times, immediately after that tap on 'Read' tab of the other device and vice versa. Repeatative 'abcdefgh' characters should be received on the device which is  reading the characters.


          I ran this test at different baud rates from 1200 to 115200 for MC75 pair, MC75A pair and (MC75+MC75A) pair and received sent characters successfully.