Module pins 

Cardputer ADV pin assignment, for reference and for code that drives pins directly. The typed equivalents live in Board.

Source: M5Stack Sch_M5CardputerAdv_v1.0 (2025-06-20), cross-checked against M5Unified/M5GFX.

Avoid UART0. Its default pins on the ESP32-S3 are GPIO43/44, which this board uses for I²S word-select and the IR LED. Log over USB-Serial-JTAG.

Modules

ext

14-pin EXT header (besides the shared SPI bus and system I²C).

grove

Grove HY2.0-4P port (5 V switchable to input).

i2s

ES8311 codec I²S. There is no MCLK line; the codec clocks itself from BCLK.

lcd

ST7789V2 LCD on SPI, write-only (3-wire, no MISO).

spi_bus

SPI bus shared by the microSD slot and the EXT header (e.g. LoRa cap).

sys_i2c

Internal I²C bus shared by the keyboard scanner, audio codec and IMU.

Constants

BATTERY_ADC

Battery voltage through a 100 k / 100 k divider (×2), ADC1.

BUTTON_G0

G0 button; hold at power-on for download mode. Active low.

FPC_IO1

Spare line on the internal 8-pin FPC connector.

IR_TX

IR LED, driven directly through 22 Ω (no carrier hardware).

KEYBOARD_INT

TCA8418 interrupt output, active low.

RGB_LED

WS2812-class RGB LED data. Powered only while lcd::BL is high.