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ESP32-S3 (DevKitC-1) pinout

ESP32-S3 (DevKitC-1) pin table: which GPIOs are free for sensors and relays, which affect booting (strapping), are taken by flash, USB or are input only, and where the ADC and I²C are. With an ESPHome example.

25 safe 11 with care 9 avoid

GPIOBoard labelUse?FunctionsNotes
GPIO0with careBOOTStrapping pin: the BOOT button, LOW at boot = flash mode.
GPIO1safeADC1_0, Touch1Free; ADC1 works with Wi-Fi on.
GPIO2safeADC1_1, Touch2Free; ADC1 works with Wi-Fi on.
GPIO3with careADC1_2, Touch3Strapping pin (JTAG source). Fine as a normal pin after boot.
GPIO4safeADC1_3, Touch4Free; ADC1 works with Wi-Fi on.
GPIO5safeADC1_4, Touch5Free; ADC1 works with Wi-Fi on.
GPIO6safeADC1_5, Touch6Free; ADC1 works with Wi-Fi on.
GPIO7safeADC1_6, Touch7Free; ADC1 works with Wi-Fi on.
GPIO8safeADC1_7, Touch8Free; ADC1 works with Wi-Fi on.
GPIO9safeADC1_8, Touch9Free; ADC1 works with Wi-Fi on.
GPIO10safeADC1_9, Touch10Free; ADC1 works with Wi-Fi on.
GPIO11safeADC2_0, Touch11Free; ADC2 is unreliable with Wi-Fi on.
GPIO12safeADC2_1, Touch12Free; ADC2 is unreliable with Wi-Fi on.
GPIO13safeADC2_2, Touch13Free; ADC2 is unreliable with Wi-Fi on.
GPIO14safeADC2_3, Touch14Free; ADC2 is unreliable with Wi-Fi on.
GPIO15safeADC2_4Free; ADC2 is unreliable with Wi-Fi on.
GPIO16safeADC2_5Free; ADC2 is unreliable with Wi-Fi on.
GPIO17safeADC2_6Free; ADC2 is unreliable with Wi-Fi on.
GPIO18safeADC2_7Free; ADC2 is unreliable with Wi-Fi on.
GPIO19USB D−avoidUSBBuilt-in USB.
GPIO20USB D+avoidUSBBuilt-in USB.
GPIO21safe—Free.
GPIO26avoidSPI flash / PSRAMConnected to the flash and PSRAM.
GPIO27avoidSPI flash / PSRAMConnected to the flash and PSRAM.
GPIO28avoidSPI flash / PSRAMConnected to the flash and PSRAM.
GPIO29avoidSPI flash / PSRAMConnected to the flash and PSRAM.
GPIO30avoidSPI flash / PSRAMConnected to the flash and PSRAM.
GPIO31avoidSPI flash / PSRAMConnected to the flash and PSRAM.
GPIO32avoidSPI flash / PSRAMConnected to the flash and PSRAM.
GPIO33with careOctal PSRAMTaken by octal PSRAM on N8R8/N16R8 modules; free on modules without it.
GPIO34with careOctal PSRAMTaken by octal PSRAM on N8R8/N16R8 modules; free on modules without it.
GPIO35with careOctal PSRAMTaken by octal PSRAM on N8R8/N16R8 modules; free on modules without it.
GPIO36with careOctal PSRAMTaken by octal PSRAM on N8R8/N16R8 modules; free on modules without it.
GPIO37with careOctal PSRAMTaken by octal PSRAM on N8R8/N16R8 modules; free on modules without it.
GPIO38safeRGB LED (v1.1)Free; the RGB LED on DevKitC-1 v1.1.
GPIO39safeJTAGFree unless you use JTAG debugging.
GPIO40safeJTAGFree unless you use JTAG debugging.
GPIO41safeJTAGFree unless you use JTAG debugging.
GPIO42safeJTAGFree unless you use JTAG debugging.
GPIO43TXwith careUART0 TXUART0 (USB-UART chip).
GPIO44RXwith careUART0 RXUART0 (USB-UART chip).
GPIO45with careVDD_SPI selectStrapping pin: keep LOW at boot.
GPIO46with careBoot modeStrapping pin: keep LOW at boot.
GPIO47safe—Free.
GPIO48safeRGB LED (v1.0)Free; the RGB LED on DevKitC-1 v1.0.

Boards route pins differently: check your board’s schematic. Strapping pins are read at power-on; if a sensor or button pulls one the wrong way, the board will not boot or will enter flash mode.

ESPHome example

esp32:
  board: esp32-s3-devkitc-1

i2c:
  sda: GPIO8
  scl: GPIO9

binary_sensor:
  - platform: gpio
    pin:
      number: GPIO6
      mode: INPUT_PULLUP
      inverted: true
    name: "Button"

A full config with sensors, keys and a pin clash check: ESPHome generator. Other boards: ESP32, ESP32-C3, ESP8266.

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