Power save with CMUX and PS Data active in UC864-E

4 thoughts on “Power save with CMUX and PS Data active in UC864-E

  1. Hi

    At the moment we’re using UC864-E with serial port connection and power save enabled in both our TE and the MT using AT+CFUN=5 and RI (#PSMRI) and DTR/RTS/etc signaling.

    Now, we want to use the CMUX and also have a PS Data connection active using one of the virtual serial ports as a dedicated port for the PPP session and one for general AT commands. And we still want to make use of the maximum power saving in both our TE and the MT (equivalent to the AT+CFUN mode above) but without exiting the CMUX mode or terminating the PS Data session when entering power save.

    So we want our TE to wake up when a new PS Data packet is received from the network and resume the PPP session and naturally being able to wake the MT when our application wants to send data or AT commands).

    I’m having a bit of a problem to see from the documention if this is possible with the UC864-E. I’ve read Telit_UC864_Software_User_Guide, Telit_CMUX_Implementation_User_Guide and the AT command spec. Can someone confirm that this is possible?

     

    Thanks, Magnus

     

    1. Dear Magnus,

       

      as described in the CMUX User Guide, AT+CFUN command can’t be used in Multiplexed Mode. Moreover the (PSC) command is not supported on the UC864, therefore it is not possible to enter in power saving when CMUX is active.

      1. Andrea,

         

        Thanks for confirming this.

         

        We did try to send the PSC command and it seems like something is happening in the UC864 when it receives that, because it won’t react to further CMUX packets until we make a call to the module.

         

        But it seems like one can exit CMUX mode while a connection is active (at least a CSD call) and then start CMUX again and resume the data exchange on the virtual port. Perhaps that can be used also on a PSD session and then use the standard power saving mode.

         

        Though, it looked like incoming data from the network side (CSD) was sent directly on the serial port after CMUX  had exited, but the module responded to AT-commands. So it was partly in command mode and partly in online mode.

         

        Regards, Magnus

      2. Andrea,

        Thanks for confirming this.

        We did try to send the PSC command to the UC864 and something happened in the module because it stopped reacting to CMUX packets. When we made a call to the module the CMUX became active again.

        We also noticed that at least for CSD calls, one can set up a call in a virtual serial port using CMUX and then exit CMUX. The CSD session is then resumed when CMUX is started again. So perhaps this can be used also in PSD sessions and use the standard power saving methods.

        Though we did see that if a CSD call had been started in a virtual serial port then after exiting CMUX the traffic from the remote terminal is sent directly to the serial port although the serial port seems to be in command mode (if we type ‘AT’ the module responds with ‘OK’). So it’s partly in command mode and partly in data mode.

         

         

        Regards, Magnus