We’ve experienced a similar problem in the past. Our automated test equipment shuts down and reapplies the power supply automatically and the open AT app would not start approx 1 in every 100 restarts. (very random though)
This was improved substantially by ensuring a AT+CPOF was called before shut down of power, but the problem still occurs occasionally.
Never got to the bottom of this. I’d be interested if you learn any more.
I have a similar problem but a little more often than 1 to 100.
I have even seen it when i made some experiments from hyperterminal, i then realized that it had changed the baudrate to 57600, and responded to AT commands whith that speed, but +CSQ answered 99,99 and a GPRS connection was not possibly.
An automated power off (i have a relay in the power) in 10 sec. did’nt solve it either . I apperently have to make a manual power off/on, to “get up” in a state that works.
Is any of you getting closer to solving the problem ??
What kind of “power off” are you doing that doesn’t work?
There are bugs in some modules/firmware where the module may start up at half the speed, and when you ask with +IPR? it will claim to be the original speed.
Ex: module configured for +IPR=115200
module starts up in half speed for some reason, +IPR? give +IPR: 115200
As far as I know, Wavecom have yet to admit that this problem exist at all, despite it being reported many times.
Forgot to add…
Since Wavecom seems to completely ignore this problem (noticed a lot on Q2406B with 6.57 fw, but not on Q24PL001 also with 6.57 but with some changes to how power up is handled that is not the same as old modules), I’d like to find any way to programmatically detect this condition and force a restart when it happens.
As I said in previous post, querying IPR does not work, so does anyone know of any other way you can detect this?
I’m not making aplikations IN the modem but im using the fasttrack as a external modem to my main processor. So the power off i’m doing is a fysical power off via a relay in the fasttrack’s power cord.
From the remote processor i can detect the faulty mode by trying different speeds to see which one the modem answers OK to a simple AT.
And i’m using 115200, so it’s possibly that it is the bug you are refering to.
I could live with a different communication speed, but my real problem is that when i does that, it responds to AT commands but GPRS connection is impossibly (as mentioned early’er).
I have off course tried a normal restart (+CFUN=1) but it dont brings the modem out of the faulty state.