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docs/use/gsm.md

@@ -0,0 +1,25 @@
+# GSM 2G gateway
+## Receiving SMS from 2G
+
+Subscribe to all the messages with mosquitto or open your MQTT client software:
+`mosquitto_sub -t +/# -v`
+
+Generate your SMS by sending an SMS to the phone number of the A6/A7 SIM card you will see :
+
+```
+home/OpenMQTTGateway/2GtoMQTT {"phone":"+33123456789","date":"2018/04/22,16:17:51+02","message":"Hello OpenMQTTGateway"}
+```
+
+## Send data by MQTT to send an SMS message with A6/7
+
+`sudo mosquitto_pub -t home/OpenMQTTGateway/commands/MQTTto2G -m '{"phone":"+33123456789","date":"2018/04/22,16:17:51+02","message":"hello"}'`
+
+This command will send by SMS the sentence "hello" and use the phone number 0123456789
+
+Arduino IDE serial data received when publishing data by MQTT
+
+![](../img/OpenMQTTGateway_serial_2G_1.jpg)
+
+Arduino IDE serial data received when receiving SMS
+
+![](../img/OpenMQTTGateway_serial_2G_2.jpg)