[Ovmsdev] Cannot reset simcom stuck in PoweringOn state without removing module power

[Michael Balzer]

Craig,

you'll need log level verbose to see all tx/rx going on (i.e. MUX commands), but debug should be sufficient for the power on sequence.

You can test setting the PWRKEY manually by "egpio output 0 1". If the simcom driver is now stuck in the power cycle loop and interferes, you should be able to
stop that by "simcom setstate PoweredOff" or "power simcom off".

Regards,
Michael


Am 05.01.20 um 05:16 schrieb Craig Leres:
> The simcom on one of my modules wedged today and had some time to poke at it. When I turn on simcom debugging I see "AT" commands once a second:
>
>     D (1199981) simcom: tx scmd ch=0 len=4   : AT
>     D (1200981) simcom: tx scmd ch=0 len=4   : AT
>
> but no responses.
>
> I wanted to see if I could talk to the simcom via the usb connector on the modem card so I sacrificed a micro usb cable and hacked the molded end off so I
> could plug it in without detaching the modem board from the main board (see attached).
>
> Next I spent a few minutes with a spare module looking for a windows 10 driver. The sim5360 (rar) archive from techship.com didn't work but the windows 8 zip
> file from here did:
>
>
> https://github.com/botletics/SIM7000-LTE-Shield/tree/master/SIM7000%20Documentation/Drivers
>
> I ended up with four com ports (at, nema, diagnostic, and audio) and was able to talk to the spare modem.
>
> Then I went out to plug into the simcom in the car. The first thing I noticed was that the blue led on the modem board is not lit and (as expected) I got
> nothing from the at com port.
>
> For completeness I tried rebooting the module but it help.
>
> I now believe wedging the simcom involves running the car for a short amount of time. In this particular case I moved the car out of the garage to make room
> for some work on my other car. An hour later I moved it back. The run time was 1-2 minutes each time. A bit later when I tested Mark's new ios app I noticed
> that the car was not reporting a location.
>
> I looked at the simcom docs a bit and it's too bad the simcom RESET pin isn't connected to a pio pin.
>
> It'll be a couple of days before I'll need the gps to work in case there are ideas of what can be done via software to wake up the simcom. I might trying add
> a simcom command to set PWKEY to an arbitrary state to see if holding it low for more than one second does anything.
>
>         Craig 

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