XMMProtocolInterfaces » History » Revision 20
Revision 19 (Denis 'GNUtoo' Carikli, 01/04/2021 09:59 PM) → Revision 20/46 (Denis 'GNUtoo' Carikli, 01/04/2021 10:01 PM)
h1. XMMProtocolInterfaces
{{>toc}}
h2. usb_sel
h3. HowTO
First you need to get a root shell in the device as the commands need to be executed as root.
Once this is done you need to switch the USB connector to the modem USB. This can be done with the following command:
<pre>
echo MODEM > /sys/devices/virtual/sec/switch/usb_sel
</pre>
Then nothing will happen, you will still be able to login through adb.
To make the device switch to the modem USB you then need to unplug and replug the USB cable between your computer and the device.
At this point, if the modem was booted, you'll see a new USB device appearing.
Some serial ports will also appear.
Tested on Replicant 6.0 0004 RC3
| Device | Distribution | Modem status | USB ids | tty |
| GT-I9100 | Replicant 6.0 0004 RC3 | Off | None | N/A |
| GT-I9100 | Replicant 6.0 0004 RC3 | Booted | 1519:0020 Comneon HSIC Device | /dev/ttyACM0 -> /dev/ttyACM6 |
| GT-I9300 | Replicant 6.0 0004 RC3 | Booted | 1519:0020 Comneon HSIC Device | /dev/ttyACM0 -> /dev/ttyACM6 |
h3. Protocols
|_. | Device |_. State |_. | state | UART |_. | Protocol |
| GT-I9100 | modem booted | /dev/ttyACM0 | AT: [[GTI9100ModemTTYACM0]] |
| GT-I9100 | modem booted | /dev/ttyACM1 | Compatible with xgoldmon |
| GT-I9300 | modem booted | /dev/ttyACM0 | AT: [[GTI9300ModemTTYACM0]] |
| GT-I9100 | modem booted | /dev/ttyACM1 | Xgoldmon waits for messages but nothing arrives |
h3. Xgoldmon
Xgoldmon seem to display things on the GT-I9100:
<pre>
# ./xgoldmon -vvvv -i localhost -t s2 -l /dev/ttyACM1
LOG:>>[HIGH]oembatt.c,310,[DISP] Thermistor : measured_value=1630666778<<
LOG:>>[HIGH]oembatt.c,137,[DISP] oem_set_batt_level : 4220<<
LOG:>>[HIGH]oembatt.c,236,[DISP] BATT : measured_value_mv=4220, AvgBattVal_mv=4007, battery_level=5<<
LOG:>>[LOW]oemdisplay.c,363,no change -> rssi:4, bat:5<<
LOG:>>[HIGH]oembatt.c,310,[DISP] Thermistor : measured_value=1630666779<<
LOG:>>[HIGH]oembatt.c,137,[DISP] oem_set_batt_level : 4225<<
LOG:>>[HIGH]oembatt.c,236,[DISP] BATT : measured_value_mv=4225, AvgBattVal_mv=4026, battery_level=5<<
LOG:>>[LOW]oemdisplay.c,363,no change -> rssi:4, bat:5<<
LOG:>>[HIGH]oembatt.c,310,[DISP] Thermistor : measured_value=1630666778<<
LOG:>>[HIGH]oembatt.c,137,[DISP] oem_set_batt_level : 4220<<
LOG:>>[HIGH]oembatt.c,236,[DISP] BATT : measured_value_mv=4220, AvgBattVal_mv=4055, battery_level=5<<
LOG:>>[LOW]oemdisplay.c,363,no change -> rssi:4, bat:5<<
</pre>
And when calling an (inexisting/invalid) number, the frames appear in Wireshark.
However on the GT-I9300 it waits for messages that never arrive.
And on the GT-I9100 there seem to be very few messages.
So maybe AT+TRACE=1 enables tracing but doesn't set the tracing verbosity.