182 lines
4.5 KiB
Markdown
182 lines
4.5 KiB
Markdown
# AT Commands User Guide
|
|
|
|
This document provides detailed usage instructions for the main AT commands supported by the H11 device.
|
|
|
|
## 1. AT+DEV_INIT_STA=GET
|
|
|
|
**Function**: Query device initialization status
|
|
|
|
**Command Format**:
|
|
```
|
|
AT+DEV_INIT_STA=GET
|
|
```
|
|
|
|
**Response Example**:
|
|
```
|
|
AT+DEV_INIT_STA=GET,4G,<4G_link>,<SIM_ready>,<NTRIP_flag>,<CSQ>,<data_back>,<upload_size>,<NTRIP_size>,GNSS,<status>,<reserved>,star,<SNR45>,<SNR48>,<SNR50>,<visible_stars>
|
|
OK
|
|
```
|
|
|
|
**Parameter Explanation**:
|
|
- `<4G_link>`: 4G network connection status (0=disconnected, 1=connected)
|
|
- `<SIM_ready>`: SIM card ready status (0=not ready, 1=ready)
|
|
- `<NTRIP_flag>`: NTRIP connection status (0=disconnected, 1=connected)
|
|
- `<CSQ>`: Signal quality (0-31, higher is better)
|
|
- `<data_back>`: Data upload status (0=idle, 1=uploading)
|
|
- `<upload_size>`: Upload queue size (bytes)
|
|
- `<NTRIP_size>`: NTRIP data queue size (bytes)
|
|
- `<status>`: GNSS module status
|
|
- `<SNR45>`, `<SNR48>`, `<SNR50>`: Number of satellites with SNR > 45/48/50 dB
|
|
- `<visible_stars>`: Total number of visible satellites
|
|
|
|
**Use Cases**:
|
|
- Check device module initialization status after startup
|
|
- Diagnose device connectivity and module status
|
|
- Monitor network and GNSS module status
|
|
|
|
---
|
|
|
|
## 2. AT+NEMATIME=SET
|
|
|
|
**Function**: Set NMEA output frequency
|
|
|
|
**Command Format**:
|
|
```
|
|
AT+NEMATIME=SET,<frequency>
|
|
```
|
|
|
|
**Parameters**:
|
|
- `<frequency>`: Output frequency in Hz (supported values: 1, 2, 5, 10)
|
|
|
|
**Response Example**:
|
|
```
|
|
AT+NEMATIME=SET
|
|
OK
|
|
```
|
|
|
|
**Error Response**:
|
|
```
|
|
AT+NEMATIME=SET
|
|
ERROR
|
|
```
|
|
|
|
**Use Cases**:
|
|
- Configure GNSS position data output rate
|
|
- Adjust positioning data update frequency based on application requirements
|
|
- Balance between update rate and power consumption
|
|
|
|
---
|
|
|
|
## 3. AT+NEMATIME=GET
|
|
|
|
**Function**: Query current NMEA output frequency
|
|
|
|
**Command Format**:
|
|
```
|
|
AT+NEMATIME=GET
|
|
```
|
|
|
|
**Response Example**:
|
|
```
|
|
AT+NEMATIME=GET,<frequency>
|
|
OK
|
|
```
|
|
|
|
**Parameter Explanation**:
|
|
- `<frequency>`: Current NMEA output frequency in Hz
|
|
|
|
**Use Cases**:
|
|
- Verify the current NMEA output frequency configuration
|
|
- Ensure frequency configuration has taken effect
|
|
- Troubleshoot positioning data update issues
|
|
|
|
---
|
|
|
|
## 4. AT+RTCMBASEPOS=GET
|
|
|
|
**Function**: Query base station position and distance from RTCM data source
|
|
|
|
**Command Format**:
|
|
```
|
|
AT+RTCMBASEPOS=GET
|
|
```
|
|
|
|
**Response Example** (when RTCM data is available):
|
|
```
|
|
AT+RTCMBASEPOS=GET,<latitude>,<longitude>,<altitude>,<distance>
|
|
OK
|
|
```
|
|
|
|
**Response Example** (when RTCM data is not available):
|
|
```
|
|
AT+RTCMBASEPOS=GET,0.0,0.0,0.0,0.0
|
|
OK
|
|
```
|
|
|
|
**Parameter Explanation**:
|
|
- `<latitude>`: Base station latitude in degrees (positive=North, negative=South)
|
|
- `<longitude>`: Base station longitude in degrees (positive=East, negative=West)
|
|
- `<altitude>`: Base station altitude/elevation in meters
|
|
- `<distance>`: Distance from device to base station in meters
|
|
|
|
**Use Cases**:
|
|
- Obtain current base station position information in RTK mode
|
|
- Monitor distance to reference station
|
|
- Assess differential positioning quality
|
|
- Verify RTK connection status
|
|
|
|
---
|
|
|
|
## Command Usage Examples
|
|
|
|
### Query device initialization status
|
|
```
|
|
→ AT+DEV_INIT_STA=GET
|
|
← AT+DEV_INIT_STA=GET,4G,1,1,1,25,0,0,1024,GNSS,1,0,star,8,5,2,12
|
|
← OK
|
|
```
|
|
|
|
### Set NMEA frequency to 1Hz
|
|
```
|
|
→ AT+NEMATIME=SET,1
|
|
← AT+NEMATIME=SET
|
|
← OK
|
|
```
|
|
|
|
### Query current NMEA frequency
|
|
```
|
|
→ AT+NEMATIME=GET
|
|
← AT+NEMATIME=GET,1
|
|
← OK
|
|
```
|
|
|
|
### Query base station position and distance
|
|
```
|
|
→ AT+RTCMBASEPOS=GET
|
|
← AT+RTCMBASEPOS=GET,31.135370,121.287729,22.467,1234.56
|
|
← OK
|
|
```
|
|
|
|
---
|
|
|
|
## Important Notes
|
|
|
|
1. **Command Format**: All AT commands start with "AT" and end with "\r\n"
|
|
2. **Case Insensitive**: Commands are case-insensitive
|
|
3. **Response Timeout**: Recommended timeout for each command is 5 seconds
|
|
4. **Response Format**: Successful execution returns "OK", failure returns "ERROR"
|
|
5. **RTCM Base Station Info**: Base station position is only available after receiving valid RTCM 1005/1006 messages
|
|
6. **Frequency Setting**: Device may need restart for frequency changes to take effect
|
|
7. **Line Ending**: Use CR+LF (\r\n) as line terminator
|
|
8. **Serial Parameters**: Default baud rate is 115200 bps
|
|
|
|
---
|
|
|
|
## Related Information
|
|
|
|
- **NMEA**: National Marine Electronics Association protocol, widely used in GPS/GNSS devices
|
|
- **RTCM**: Radio Technical Commission for Maritime Services, data format for differential positioning
|
|
- **RTK**: Real-Time Kinematic positioning technology
|
|
- **CSQ**: Signal Quality indicator (0-31, where 31 is excellent)
|
|
- **SNR**: Signal-to-Noise Ratio measured in dB
|