Power Saving Modes Slow Idle and Slow standby modes


Hello all,

Has anyone been able to successfully use the Slow Idle mode when connected to TCP via SIM/GPRS control?

For example what I would like to do is the following:

  • Power up
  • Initiate w32k=1
  • DTR low (disabling low power mode)
  • Subscribe to SIM with pin
  • On SIM event FULL_INIT start connection to GPRS
  • Once GPRS connected start TCP connection
  • Once TCP connected communicate to host
  • Once successfully communicated to host set DTR High (enabling low power mode)
  • Now in low power mode (after x seconds) until timer event happens

(using Oasis 2.10 with a 2686h CPU)

What I am initially doing is testing that the device can go into low power mode after a successful SIM init but when I trigger the DTR line high at this point and after waiting longer than 15s (as stated in documentation) the device dose not go into slow idle mode, hence, if i cannot get this to work then I cannot see it working after all the other items above have been done.

I have managed to achieve low power mode before attempting the sim action above.

Anyone have any ideas about this?

On this basis I have tried another approach, i.e. trying to use the slow standby mode. I know this does not give you the functionality that slow idle mode gives.

For example what I have tried so far is this:

  • power up.
  • start a regular timer to perform set operations, including reading at+wbhv=1,x state.
  • adl_atUnSoSubscribe to commands “+CALA:”.
  • Set an Alarm using the at command at+cala.
  • When alarm event happens:
    • send internal command for a new alarm to trigger.
    • send internal commands at+wbhv=1,2, Set DTR low via GPIO then perform a internal at+cfun=1 operation.
  • After x seconds of the unit having restarted the unit goes into low power mode.
  • When next alarm event happens (during slow standby mode):
    • send internal command for alarm trigger (to go back into slow standby mode), at+cala.
    • send internal commands at+wbhv=1,0 then perform a internal at+cfun=1 operation.

The idea being that the application will loop round and round going between slow standby and default modes.

The problem I am having with this idea is that after the last stage above I am not seeing the device come back to the default mode (Fast Idle Mode), anyone have any idea’s??




I have the same problem,

Wich GPIO do you try to use to set the DTR?



Hi Mat56,

I am using GPIO24 at present, I was using 25 but I decided to avoid using a multiplexed signal line.



First option sounds better, but I think DTR must set as low (like in the second option).
Anyway I have never used the W32K mode but I have think you must send the AT commands trough a physical serial port, no GSM/GPRS activity shall be required, all physical ports must be in AT mode, and all DTE of open ports shall be set to low. Check all these conditions are fulfilled.
I don’t know if this helps you. Good luck.