USB × 1: USB 2.0, can be used for AT communication,
capturing log and upgrading software version; I2C × 3: Support
standard mode 100KHz and fast mode 400KHz, and the internal
software of the module is pulled up by default SPI × 3: Two
dedicated SPI interfaces (SPI CAM and SPI LCD) and one
dedicated SPI FLASH interface ADC × 2: Supports 12-bit ADC,
voltage range 0 to VBAT UART × 2: Used for sending AT
commands or data transmission, the baud rate defaults to
115200bps, and the main serial port UART1 can support RTS
and CTS hardware flow control
GPIOs
KEYs
DEBUG_UART × 1: Debug serial port for AP log output, and the
baud rate is 2M
SIM × 2: Support 1.8 V and 3V cards, support hardware two
SIM card interfaces, but whether to support dual cards is mainly
distinguished by software
LCD × 1
CAM × 1
PCM/I2S: For external audio Codec