SIMDET and QSS based SIM card presence detection

3 thoughts on “SIMDET and QSS based SIM card presence detection

  1. Hi,


    I would like to use the software based SIM card presence detection (e.g. holder without  SIM detect pin). For that I use the following algorithm:







    if QSS status == 1 –> SIM present

    if QSS status == 0 –> SIM not present


    This seems to be working fine. My questions are:

    a) is this solution good?

    b) what are the times I need to wait between the issuing of the commands? For example, If I don’t wait after the AT#SIMDET=1 (or wait for ~20ms) the SIM is never detected. 


    I’m using GL-865.


    Best regards,

    Andrzej Telszewski

    1. Hi,


      the solution is good.

      The delay between AT#SIMDET=0 and #SIMDET=1 should be increased, specially if the SIM is ready (+CPIN: Ready) and the module registered. In this case the timeout should be 5 seconds tonot interfere with the detach procedure.