| 101 | ==== AT Commands ==== |
| 102 | |
| 103 | AT Commands are supported on one of the /dev/ttyUSB lines. |
| 104 | |
| 105 | * [https://www.u-blox.com/sites/default/files/SARA-R4-SARA-N4_ATCommands_%28UBX-17003787%29.pdf u-blox SARA-R4/N4 series AT Commands Manual, Doc. No. UBX-17003787] |
| 106 | |
| 107 | Radio Access Technology (RAT): |
| 108 | * R4 Series of Ublox Modems support NB-IoT and Cat-M1 and are enabled default. NB-IoT hasn't spread much in the USA so turning that off can speed up connections to CAT-M1 |
| 109 | {{{ |
| 110 | AT+URAT? # Query the radio access technology; 7 = Cat-M1, 8 = NB-Iot, 7&8 = both |
| 111 | AT+URAT=7 # Cat-M1 only |
| 112 | AT+URAT=8 # NB-IoT only |
| 113 | AT+URAT=7&8 # both |
| 114 | }}} |
| 115 | |
| 116 | Operator selection: |
| 117 | {{{ |
| 118 | AT+COPS? #is to check what network currently on |
| 119 | AT+COPS=? #is to check what networks are available |
| 120 | +COPS: (1,"311 480","311 480","311480",7),(2,"AT&T","AT&T","310410",7),(1,"313 100","313 100","313100",7),,(0,1,2,3,4),(0,1,2) |
| 121 | AT+COPS=1,2,"310410" #sets to AT&T |
| 122 | AT+COPS=1,2,"311480" #sets to verizon |
| 123 | AT+COPS=0,0 #To go back to automatic carrier selection (which is typically recommended) |
| 124 | }}} |