Note: Before you begin, please ensure your SIM is successfully activated in the Hologram Dashboard.
For instructions on sending AT commands to a device, click here. Keep in mind that the instructions are written for Hologram Novas but use basic serial communication and standard AT commands so the same commands can be used on all modems. If you are unable to open a serial communication channel with your modem, contact your original equipment manufacturer for instructions on sending AT commands to your device.
Modem, Module, & SIM Diagnostic Procedure
Using your favorite terminal program (Screen, Teraterm, Putty, GTKTerm, etc.), run the following commands and record their outputs. Copy this table and use the actual response field to paste your answers.
Note, the last command, below, may take up to 5 minutes to complete.
| Command | Function | Sample Response | Notes | Actual Response |
| AT | Attention | OK | Determines if device can send commands | |
| ATI | Module Number | SARA-U201-03B-00 | Device Type | |
| AT+CGMI | Manufacturer Specific Identity | u-blox | Manufacturer | |
| AT+CGMM | Manufacturer Specific Model Identity | SARA-U201 | Manufacturer Model Identity | |
| AT+GMM | Manufacturer Specific Model Identity | SARA-U201 | Manufacturer Model Identity | |
| AT+CPIN? | Check The SIM PIN | +CPIN: READY | Hologram SIMs do not require a SIM PIN | |
| AT+CCID | Check The SIM ICCID | +CCID: 1234567890123456789 | ICCID is a unique SIM identifier | |
| AT+CRSM=176,28539,0,0,12 | Read Data File 28539 In Binary Mode | +CRSM: 144,0,"FFFFFFFFFFFFFFFFFFFFFFFF" |
Forbidden or Restricted Network list All F's indicate no Networks forbidden |
|
| AT+CFUN? | Determine What Mode the Module Is In | +CFUN: 1,0 | Full functionality mode is needed | |
| AT+CSQ | Signal Quality | +CSQ: 22,4 |
Returns multiple values to indicate signal strength, use device command manual to decipher |
|
| AT+CREG? | Network Registration Status | +CREG: 0,5 | GSM & SMS Network Registration | |
| AT+CGREG? | GPRS Network Registration Status | +CGREG: 0,5 | 3G Network Registration | |
| AT+CEREG? | EPS Network Registration Status | +CEREG: 2,5,"MI9S","25SS404",8 | 4G LTE Network Registration | |
| AT+CGDCONT? | Read PDP Context Parameters (APN) | +CGDCONT: 1,"IP","hologram","0.0.0.0",0,0 |
APN should be hologram Verify your device manual but generally AT+CGDCONT=1,"IP","hologram" will set APN |
|
| AT+CGACT? | PDP Context Activation | +CGACT:1,1 | Indicates which PDP context is being used and if that PDP context is active.
The active context (1 in this example) should match the ext ID of the PDP context where the APN is set to hologram for connectivity |
|
| AT+COPS? | Operator Selection Status and Current Operator | +COPS: 1,2,"310260",2 |
Displays MCC + MNC of Network connected to. The last number is the RAT (Radio Access technology): 0 for GSM, 2/3 for 2G/3G, 7 for LTE, 8 for CAT-M1, 9 for Nb-IoT |
|
| AT+COPS=? | Networks In Reach |
+COPS:(1,"AT&T","AT&T","310410",2) If the module returns an error, please try again. This command can take up to 3 minutes to run. |
Network Operators or Network MCC+MNC are displayed for available Networks and their associated Region |
|
If you are not seeing the AT commands, you are typing try sending ATE. If you prefer, you can run this script for the diagnostics to automatically execute.