The M5Stamp C6LoRa is a small LoRa SMD module featuring the ESP32-C6 Wi-Fi 6, Bluetooth LE, and 802.15.4 microcontroller paired with the SX1262 LoRa transceiver for efficient high-speed and long-distance communication. It is designed for applications such as smart agriculture, remote meter reading, industrial monitoring, and long-range outdoor wireless control systems.
Measuring 18 × 15 × 2.3 mm, the module is ideal for systems with limited space and compact embedded designs. M5Stack has equipped it with an SGM13005L4 low-noise amplifier to enhance reception and a PI4IOE5V6408 I/O expander to control LoRa signals using fewer ESP32-C6 GPIO pins.
M5Stamp C6LoRa specifications:
– SoC: Espressif Systems ESP32-C6
– CPU: Single-core 32-bit RISC-V up to 160 MHz, low-power RISC-V core @ up to 20 MHz
– Memory/Storage: 512KB SRAM, 320KB ROM
– Wireless: WiFi 6, BLE 5.3, 802.15.4
– Storage: 16 MB external NOR flash
– Wireless:
– 2.4 GHz WiFi 6, Bluetooth 5.3, and 802.15.4 radio for Thread/Zigbee via ESP32-C6
– LoRa:
– Semtech SX1262 LoRa transceiver (850 to 960 MHz)
– Max transmit power: +22 dBm
– Max receive sensitivity: -148 dBm
– SGMICRO SGM13005L4 Low Noise Amplifier (LNA) for improved reception
– Antennas: 2x IPEX-4 connectors for external Wi-Fi and LoRa antennas
– Expansion:
– 16x GPIOs routed from the ESP32-C6 (G2, G4 – G11, G15 – G18, G20 – G22)
– 5x extended I/Os (EXT_P0 – P4) via a PI4IOE5V6408 I2C I/O expander
– Power:
– 3.3V DC input via VDD_3V3 pin
– 3.7V to 5V DC input via BAT pin
– Dimensions: 18.0 x 15.0 x 2.3 mm (SMD surface-mount form factor)
– Weight: 1.7 grams
The LoRa control signals are managed through the I/O expander, requiring a specific initialization to activate the LoRa radio. This involves resetting the SX_NRST pin, setting the SX_ANT_SW high for antenna switch operation, and enabling the amplifier chip by setting SX_LNA_EN high. Firmware flashing can be achieved via UART (using a USB-TTL adapter and pulling GPIO9 low) or direct USB pins.
When powering the module via the BAT pin (3.7V – 5V), the MODULE_EN pin must be set high to activate the power supply. No action is required on MODULE_EN when using VDD_3V3.
For software, M5Stack offers a Quick Start guide for Arduino IDE, PlatformIO configuration details using the m5stack-stamp-c6lora environment, M5Unified, and RadioLib libraries. UiFlow visual programming support is in progress. Hardware documentation, including PDF schematics, PCB layout files, KiCad footprint library, and 3D models for mechanical integration, is available on the documentation website.
The Stamp C6LoRa SMD module is available for $12.95 on AliExpress and the M5Stack store.