The TFGPSLITE01 module is a GNSS (Global Navigation Satellite System) module based on the u-blox CAM-M8 series GNSS receiver. This module is primarily designed for use in small, simple unmanned aerial vehicles (UAVs), where basic GPS functionality is required. It utilizes the "Basic GPS Port" as defined in the Pixhawk connector standard (DS-009).
Despite being functional, TFGPSLITE01 exhibited several performance limitations during testing:
- Time-to-first-fix (TTFF) under favorable conditions was in the range of several minutes, which is not suitable for applications requiring fast initialization.
- The module struggled to maintain a stable fix, further reducing its reliability.
Due to these shortcomings, the module has been superseded by TFGPSLITE02, which utilizes a different GNSS receiver to address these issues and achieve significantly better performance.
- GNSS Constellations: Supports GPS and GLONASS constellations by default.
- Interfaces:
- UART: 9600 baud rate (default), 8 data bits, no parity bit, 1 stop bit.
- I2C compliant DDC (slave mode).
- Power Requirements:
- Input Voltage: 5.4 V.
- Backup Voltage: 1.4–3.6 V.
- Antenna Options: Integrated GNSS antenna (the ability of module to use an external antenna is not applied).
- Connector: JST GH series connector, compatible with the Pixhawk "Basic GPS Port".
- Receiver Type: 72-channel concurrent GNSS receiver.
- Sensitivity:
- Cold start: -148 dBm.
- Tracking: -167 dBm.
- Accuracy:
- Horizontal Position: 2.5 meters (CEP, 50% under ideal conditions).
- Time-to-First-Fix (TTFF):
- Cold Start: ~26–30 seconds (theoretical).
- Aided Start: ~2–3 seconds (theoretical).
- Real-world Performance: Multiple minutes for cold start, even under good conditions.
The TFGPSLITE01 uses the Pixhawk "Basic GPS Port" pinout as described in the DS-009 standard:
| Pin | Signal | Voltage |
|---|---|---|
| 1 | VCC | +5 V |
| 2 | TX (OUT) | +3.3 V |
| 3 | RX (IN) | +3.3 V |
| 4 | I2C1 SCL | +3.3 V |
| 5 | I2C1 SDA | +3.3 V |
| 6 | GND | GND |