SPI Flash: Built-in 4M. Supports 2.4GHz Wi-Fi and Bluetooth Low Power 5.0, suitable for all kinds of IoT devices with wireless connection needs. WiFi:802.11b/g/n protocol, 2.4GhHz. Bluetooth:BT 5.0. Pin Interface: 1xI2C, 1xSPI, 2xUART, 11xGPIO(PWM), 4xADC.
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