Using DTR to get into command mode

2 thoughts on “Using DTR to get into command mode

  1. Hi,

    We are having a problem with the HE910 getting it to switch
    back to command mode using the DTR line. We are using the AT&D1
    command and opening our connection with AT#SD. When we toggle the DTR
    line, the chip doesn’t respond back, stays in data mode. We are driving
    DTR low usually, then we toggle DTR line high for 50ms, then back down. I
    don’t see any timing specs on this signal anywhere. Any ideas?

     

    THanks,

    Greg

    1.  

      Luca answering:

       

      Here is my log, DTR seems to be working ..

      AT#SGACT = 1,1

      AT#SGACT = 1,1



      #SGACT: 2.192.35.1



      OK


      AT#SD=1,0,10450,"88.37.127.164",0,0,0


      AT#SD=1,0,10450,"88.37.127.164",0,0,0


      –>EVENT: DCD 



      CONNECT


      TEST STRING …LOOP COUNTER 1


      TEST STRING …LOOP COUNTER 2


      TEST STRING …LOOP COUNTER 3



      DTR OFF



      TEST STRING …LOOP COUNTER 4




      OK




      SRING: 1



      DTR ON



      AT+CGMR


      AT+CGMR



      12.00.003



      OK