Device
You do not instantiate gnss-session objects yourself: you request a reference to one by calling hardware.gnss.open(). While at least one gnss-session object reference is in scope, the cellular modem’s GNSS sub-system will remain available for use and further calls to hardware.gnss.open() will throw an exception. You will only receive a reference to a new gnss-session object if all the previously received references have gone out of scope, or been manually set to null.
All interactions between your code and the GNSS sub-system are made by calling gnss-session member methods. The majority of these methods return data synchronously and in the form of a table of standard structure. Every table provided by a gnss-session object member method synchronously or asynchronously will contain the key status; its value will be one of the following:
| Value | Meaning |
|---|---|
| 0 | Success |
| Any integer > 0 | A CME error code issued by the modem |
| Any integer < 0 | An error code issued by impOS |
| impOS Error Code | Description |
|---|---|
| Error Code | Description |
| -1 | Timeout. The modem took too long to respond. Issue the command again |
| -2 | The modem is not ready. Back off and try again shortly |
| -3 | A modem command is already in flight. Back off and try again shortly |
| -4 | An invalid parameter was passed to modem |
| -5 | A transmission failure. The modem has stopped reading its UART. This usually indicates a hardware error |
| CME Error Code | Description |
|---|---|
| 501 | Invalid parameter value |
| 502 | Operation not supported |
| 503 | GNSS sub-system busy |
| 504 | Session already active |
| 505 | Session not active |
| 506 | Operation timed out |
| 507 | Function not enabled |
| 508 | Time information error |
| 509 | Quectel gpsOneXTRA function not enabled |
| 512 | Validity time is out of range |
| 513 | Internal modem resource error |
| 514 | GNSS locked |
| 515 | End by E911 |
| 516 | GNSS not yet fixed |
| 517 | Geofence ID does not exist |
| 549 | Unknown error |
The returned table may contain other keys in addition to status. These will depend on the specific method called, so please see the individual methods’ own documentation for details.
The gnss-session object has the following member methods: