Difference between revisions of "GSM/GPRS"

Revision as of 10:28, 13 May 2011

This page will summarize informations to use the GSM/GPRS module of the APF27Wireless board and the APF51Dev (optionnal).

Introduction

GSM/GPRS are generally driven through the RS-232 bus. AT commands are used to dialog with the module.

• GSM MODEM of the APF27Wireless extension board (APW) is connected to the UART2 (/dev/ttySMX1) of the APF27.
• GSM/3G MODEM of the APF51Dev is connected to the i.MX processor through an UART implemented in the FPGA. So the corresponding bitfile has to loaded before trying to access the MODEM.

Both are using a Sagem's Hilo module. Hilo AT commands can be found here

Linux configuration (APF27Dev only)

• Linux will have to be configured in order to tell that an APW is connected to your APF27Dev:

$ make linux26-menuconfig

System Type  --->
    Freescale MXC Implementations  --->
            ...
            Extension board (Wireless (APW))  --->
       [*] GSM/GPRS Modem (NEW)
       [ ] Bluetooth & WiFi module (NEW)
       [ ] CSI (Camera) pass-through (NEW)
       [ ] GPS module (NEW)

$ make linux26

• reflash you Linux kernel

Usage

Configure serial port

APF27

# stty -F /dev/ttySMX1 raw -echo -echoe -echok

APF51Dev

• Don't forget to put "Wireless" jumper on your APF51Dev (near microSD connector)

# load_fpga top_gsm_gps_firmware.bin
# modprobe irq_ocore
# modprobe 8250
# insmod board_irq_mng.ko
# insmod 16750_ocore.ko      
serial8250.0: ttyS0 at MMIO 0xb8000020 (irq = 320) is a TI16750

Bring MODEM out of reset state (POK_IN pin, connected to PMIC GPIO6):

# modprobe wm831x-gpio
# echo 245 > /sys/class/gpio/export
# echo out > /sys/class/gpio/gpio245/direction
# echo 1 > /sys/class/gpio/gpio245/value

AT commands

• Sending AT commands with cu utility (be sure to have installed it before):

# cu -l /dev/ttySMX1

• Check module presence:

ATI3
SAGEM HiC,A.005.00

OK

• Get constructor name:

AT+CGMI
SAGEM

OK

• Get model name:

AT+CGMM
HILO GPRS

OK

• Enter PIN code:

AT+CPIN="1234"

OK

• Check PIN code status:

AT+CPIN?
+CPIN: READY

OK

Note: Don't launch further AT commands if PIN code wasn't entered successfully

• Check module status (0 Ready, 1 Unavailable, 2 Status unknown, 3 Ringing, 4 Call in progress, 5 Asleep):

AT+CPAS
+CPAS: 0

OK

• Voice call "123456789"

ATD"123456789";
OK

• Terminate current call:

ATH
OK

Tools to look at

• http://www.gnokii.org/
• http://www.alamin.org/en/index.html
• http://www.gammu.org/wiki/index.php?title=Gammu:Main_Page
• http://gatling.ikk.sztaki.hu/~kissg/gsm/index.html

Links

• HiLo 3G documentation at Sagem
• HiLo AT Commands
• SMS tutorial
• http://wiki.openmoko.org/wiki/Neo_1973_and_Neo_FreeRunner_gsm_modem
• AT Test commands
• Les commandes AT