GPS Controller Powering Down by itself

6 thoughts on “GPS Controller Powering Down by itself”

1. Device : Telit HE910
   Device Firmware Version : 12.00.005
   Host : imx28
   Communication : USB (Always connected)
   VBATT : 3.9 volt (Always)

   I invoked cmuxt as in below line
   cmuxt -d -p /dev/ttyACM0 -m he910

   As a result, 3 TTY ports got created ttyMUX1 , ttyMUX2, and ttyMUX3

   The way we have engaged Telit HE910
   ttyMUX1 : Locked for ppp connection
   ttyMUX2 : Continuously Receive Signal Strength, Network Operator Name, and few radio parameters
   ttyMUX3 : Used for receiving GPS messages

   No data is sent towards /dev/ttyMUX3. Even then, GPS Controller powers down by itself and powers up automatically by itself in 5 – 8 seconds.
   I could observe the response for AT$GPSP? as 0 during this period of time. After this period of time, GPS controller is UP by itself.

   After a day of continuous usage of Telit HE910 as explained above, we have observed the problem being occured around 3 – 4 times.

   Let me know if some one needs additional information to resolve this problem

   Thanks.

   1. 
      

      Hi,

      to check why there is this behaviour I need more informations:

      1) I need AT command sequence used to try to reproduce here the scenario

      2) Just to clarify the issue: GPS messages are received on ttyMUX3. For some reasons sometimes for 5-8 seconds GPS sentences are not received anymore and the GPS is off. Is it correct?

      1. To Turn On GPS on ttyMUX3, below commands are executed over ttyMUX3
         
         AT$GPSP=1
         AT$GPSNMUN=1,1,1,1,1,1,1
         
         And your understanding is correct about the issue. The problem of GPS Controller powering down by itself and power up by itself, happened 4 times in 24 hours.
         And, duration of the problem is between 5 and 8 seconds.

         Thanks.

         1. Is there anything else I could provide to help resolve the problem ?

            Thanks.

            1. Hi,

               I
               tried here to reproduce your scenario: my test ran for 8 hours and the
               GPS was always up and running. I’m working to run the test for 24 hours
               (as yours). In the meantime it would be nice if you could collect a
               trace of the module (if it’s possible) with the TTC trace tool (you can
               download it form this link
               :https://tcloud.telit.com/public.php?service=files&t=41e267117f838f5bbf1ea8cbe4b1d3b3
               )

            2. Cosmin

               Sorry that I took some time.

               I will get back to you if I again observe this GPS controller powering off/on by itself.

               Regarding TTC trace tool:
               Our custom board has HE910 USB lines connected to Freescale Linux processor.

               To use TTC Trace tool, we will need to connect HE910 USB lines to Windows PC.

               To do that, we will have to do some hardware modification to our board and then only HE910 can connect to Windows.

               We already have corrupted a board because of the hardware modification while trying to update firmware of the HE910. We are no more able to talk to HE910 (either through Windows or Freescale Linux processor) in one of our custom boards.

               We do not want to risk another product of us. So, connecting HE910 to Windows is not going to happen and for us to use TTC trace tool is not possible, until we figure out, what caused the board to corrupt the HE910 in our hardware modification process.