I stumbled into some strange behaviour of a modem.
Every time the unit is resetted with power off/on, it sends out “OK” on the serial port even though I’ve not sent any command and its even before “+WIND: 3”!!
It doesn’t matter if I got the serial port connected or not, or if flowcontrol is enabled/disabled.
However, the “OK” is not sent out after a “+CFUN=1”
It seems like it is caused by the fact that an OpenAT application has been running on the unit and later disabled.
But the “OK” does not disappear even if Open AT is disabled/deleted (+WOPEN=3, =4, and =0) or even if I download the whole GSM core firmware.
I’ve also tried to reconfigure every command I can think of that can cause somthing like this.
Unit is Q2406B with 6.41b and Open AT 2.10.
Anyone seen this before and know how to get rid of this unwanted “OK”?
Is this a Wavecom bug?
Is there a workaround?
This should be the bug of 6.41b firmware.
In 6.41c firmware release note there is stated “Correct Problem” : “OK is displayed when resetting the module”.
I tried 6.41c and get no extra “OK”, but not yet tried 6.5x