Lantronix M110 Series User Guide - Page 14

Communication with the Modem After the communications between the both has been established, refer to below AT commands for start using the modem. AT Command AT+CGMI AT+CPIN=XXXX AT+CSQ AT+CREG? ATD; ATH Description To check the module manufacturer identification To enter a PIN code (if required) (XXXX is actual PIN) To verify the received signal strength To verify the network registration status To initiate a voice call To end the above voice call 7.3 Received Signal Strength The modem can only establish a call or data session when the received signal strength is sufficient. In terminal window, enter AT+CSQ to see the received signal strength, then the modem will response in the below format; +CSQ: , or , or , or , where; : Received Signal Strength Indication : channel Bit Error Rate (GPRS) : channel Bit Error Pattern (EGPRS) : Energy per Chip Noise ratio (UMTS) : Reference Signal Received Quality (LTE) For SMS, voice and data operation, please refer to the below table for sufficient RSSI levels; RSSI Level 6 to 8 10 to 12 13 to 31 99 Description SMS/Voice SMS/Voice/Data All of above, to maximum RSSI level Not measurable 7.4 Network Registration To verify network registration, first ensure the SIM card has been provisioned. If the model has embedded SIM, first ensure the modem has been activated by the network provider. M110 Series User Guide 14