WSAL23721 – L76K GPS Module/en

Documentation notice: This technical documentation was independently rewritten from an archived supplier source. Check technical details and commands against the product version and manufacturer documentation before use.

Summary

Technical overview of the Waveshare L76K GNSS module: interfaces, parameters, NMEA/PCAS commands, and integration with common controllers.

Related products at JW Tech

WSAL23721 – L76K Multi-GNSS Module, Supports GPS, BDS, QZSS

Technical overview

The L76K supports GPS, GLONASS, BeiDou (BDS) and QZSS; it uses the AT6558R chip with 32 tracking and 72 acquisition channels on L1.
Interfaces: UART (TX/RX), PPS, reset, I²C (LC76G/L76B only), and antenna open/circuit detection.
Power supply: 2.7–3.4 V; current draw is about 29 mA in tracking (GPS+BDS) and about 8 µA in RTC backup mode.
Positioning accuracy: 2.0 m CEP; velocity accuracy 0.1 m/s; max update rate 5 Hz; default baud rate 9600 bps.
NMEA-0183 output includes e.g. $GNRMC, $GNGGA, $GNGSV; prefixes such as GP=GPS, BD=BeiDou, GL=GLONASS, GA=Galileo, GN=multi-satellite system.
PCAS commands allow configuring baud rate ($PCAS01), positioning interval ($PCAS02), NMEA output sentences ($PCAS03), satellite system selection ($PCAS04), and restart modes ($PCAS10).
Raspberry Pi connection: TX to P15 (GPIO14), RX to P14 (GPIO8); debugging via Minicom or U-center is possible.
Supported demos: C/Python for Raspberry Pi, Arduino, ESP32, Jetson Nano; all demos use UART communication.
TTFF: cold start autonomous ~30 s, with AGNSS ~5.5 s; warm start ~30 s autonomous or ~5 s with EASY™; hot start ~2 s.
Operating temperature -40 to +85 °C; storage -40 to +90 °C; weight 0.4 g; dimensions 9.7 × 10.1 × 2.4 mm (LCC package).

Commands and examples – verify before use:

$PCAS01,5*19
$PCAS01,1*1D
$PCAS02,1000*2E
$PCAS03,1,1,1,1,1,1,1,1,0,0,,,0,0*02
$PCAS04,3*1A
$PCAS10,0*1C

Notes and version constraints

Checksums (<Checksum>) must be recalculated after modifying any PCAS command.
Indoor positioning is unreliable; place the module or antenna by a window or outdoors for a reliable fix.
Cold start takes about 35 s under normal conditions; poor weather can make it longer or cause failure.
Raw GPS coordinates are uncorrected geocoordinates (“lunar coordinates”); map applications require additional conversion depending on the provider (e.g., Baidu vs. Google).
If position prints as 0,0 or the program hangs: place the device outdoors with the antenna facing down; positioning data should appear within 45 s of power-on.
The 2.5 m error bound applies only in open environments with clear weather; other conditions may produce larger deviations.

Source and revision record

L76K GPS Module - Waveshare Wiki
Source revision: 89560
Captured: 2026-09-04T03:19:49+00:00
SHA-256: 1393636ecd562f6a3c2093331a0bda220726be08edb26655df93ae6f91a20dac