ZTE modem

ZTE MG3732

Vayu 3GHN-D comes with ZTE MG3732 3G modem. ZTE modem creates 4 ports :

/dev/ttyUSB0

/dev/ttyUSB1

/dev/ttyUSB2

/dev/ttyUSB3

The USB drivers are already there in the pre included debian wheezy images already available for beaglebone black.

Module Power on/off and reset

The module can be powered on/off by either using the push button switch S1 or GPIO45.

Power on

The module will be turned off after power-on normally. In the state of power off, provide a low level pulse more than 50ms to ON/OFF PIN to turn on the module.

The same can be done with the help of gpio45.

setout 45 high

or

cd /sys/class/gpio
cd gpio45
echo “high” > direction

Power off

In the state of power on, provide a 2000ms low level pulse to ON/OFF  PIN to turn off the module.

The same can be done with the help of gpio45

setout 45 low 

or

cd /sys/class/gpio
cd gpio45
echo “low” > direction

This can also be done by AT commands:

AT+$MYPOWEROFF

Soft Reset

In the state of power on, provide a low level pulse more than 2000ms to /RESET PIN  to reset the module. After reset, the module will be turned off.To turn on the module, provide a low level pulse more than 50ms to ON/OFF PIN.

setout 45 low ; sleep 2 ; setout 45 high

or

cd /sys/class/gpio
cd gpio45
echo “low” > direction ; sleep 2 ; echo “high” > direction

Hard Reset

There may arise some siuations when you need to hard reset the modem as it is not responding ro any AT commands or there may be some other proble. In such cases, gpio60 can be used:

The same can be done by:

cd /sys/class/gpio
cd gpio60
echo “low” > direction ; sleep 2 ; echo “high” > direction 

Note: The USB drivers are already there in the pre included debian wheezy images available for beaglebone black.

Note : You can check the presence of modem by the use of “lsusb”.The PID:VID detected for 3GHN-D is "19d2:ffeb" Also attachment of ports can be seen with the help of “dmesg | grep -i usb”. For detailed use of the commands, see “Power on modem” section on the SW startup guide for Vayu 3G page

AT commands

All the AT commands can be executed on the /dev/ttyUSB1 with serial port settings as 115200 8N1.

Note : If the AT command/ppp connection is not established, please look at the Module power on/off procedure again. Maybe the module has not started properly.

Wvdial/ppp connection

The ppp connection can be established using the /dev/ttyUSB3 port at a baud rate of 115200. Make the suitable corrections in the /etc/wvdial.conf file.

Establish the connection using:

wvdial

Note : For detailed instruction, see the “wvdial configuration for debian wheezy” section above.

Note : If the ppp connection is not succesfull, make sure of the changes in the /etc/wvdial.conf file.