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NVS Protocol Tracking & Navigation: Technical Resource
This technical guide covers the NVS protocol (Port 5101) implementation for the CH-5707 fleet tracker and the NVS-RTK-M high-precision module.
1. Device Comparison Table
| Feature | CH-5707 (Standard) | NVS-RTK-M (High Precision) |
|---|---|---|
| Primary Application | Logistics & Asset Tracking | Drones, AgTech & Surveying |
| Accuracy | ~2.5 Meters | 1cm Horizontal (RTK Fixed) |
| GNSS Engine | Multi-GNSS (L1) | Multi-Band (L1/L2/L5) |
| Protocol Port | 5101 | 5101 / BINR / NMEA |
| Mounting | External Housing (IP67) | OEM Module / SMT Layout |
2. Technical Wiring Diagrams
CH-5707 Interface
[PIN 1] RED —> Power Input (+9V to +36V DC)
[PIN 2] BLACK —> Ground (GND)
[PIN 3] ORANGE —> ACC (Ignition Status)
[PIN 4] YELLOW —> Digital Output (Relay/Immobilizer)
[PIN 5] GREEN —> RS232-TX (To PC/Peripheral)
[PIN 6] WHITE —> RS232-RX (From PC/Peripheral)
[PIN 7] BLUE —> Analog Input (0-30V Fuel Level)
[PIN 8] GRAY —> Digital Input (Panic Button)
[PIN 2] BLACK —> Ground (GND)
[PIN 3] ORANGE —> ACC (Ignition Status)
[PIN 4] YELLOW —> Digital Output (Relay/Immobilizer)
[PIN 5] GREEN —> RS232-TX (To PC/Peripheral)
[PIN 6] WHITE —> RS232-RX (From PC/Peripheral)
[PIN 7] BLUE —> Analog Input (0-30V Fuel Level)
[PIN 8] GRAY —> Digital Input (Panic Button)
3. Essential SMS Configuration Commands
# Set Server (IP, Port, Protocol:0=TCP)
SERVER,0,123.123.123.123,5101,0#
SERVER,0,123.123.123.123,5101,0#
# Set APN (Carrier, User, Password)
APN,internet.provider,guest,guest#
# Set Polling Interval (Moving, Static)
TIMER,20,3600# (20 sec moving, 1 hour static)
# Check Current Settings
PARAM#
4. Troubleshooting RTK Connectivity
Common Fixes for NVS-RTK-M:
- Fix Type: If stuck in ‘Float’, ensure you have >8 satellites with SNR over 35dBHz.
- Baud Rate: Default for NVS modules is often 115200 bps. Check serial mismatch.
- Base Station: Ensure the RTCM 3.x stream is reaching Port 5101 for correction.
- Antenna: Must use an active Multi-Band GNSS antenna with 3-5V LNA power.
5. Glossary of NVS Proprietary Messages
For developers parsing raw NVS protocol streams via Port 5101:
$PNVG: Manufacturer specific NMEA header for NVS proprietary data.
BINR (Binary): The raw binary protocol used for high-update rates and raw measurements.
Message 0x4B: Navigation solution packet (Latitude, Longitude, Altitude).
Message 0x27: Detailed Satellite Visibility and Signal-to-Noise Ratio (SNR).
Message 0xD7: RTK Status Information (Fixed vs. Float status).
