ESP8266 – Best Pins to Use

ESP8266 Peripherals

The pins highlighted in green are OK to use. The ones highlighted in yellow are OK to use, but you need to pay attention because they may have unexpected behavior mainly at boot. The pins highlighted in red are not recommended to use as inputs or outputs.

LabelGPIOxInputOutputAt the BootNotes
D3GPIO00pull-upOKBoot fails if pulled-downConnected to FLASH button
D10GPIO01TXOKHIGH
Boot fails if pulled-down
UARTS (Serial ports)
debug output
D4GPIO02pull-upOKHIGH
Boot fails if pulled-down
D9GPIO03OKRXHIGHUARTS (Serial ports)
D2GPIO04OKOK (PWM)
 SDA (I2C)
D1GPIO05OKOK SCL (I2C)
  
 SD2GPIO09HIGH
 SD3GPIO10HIGH
D6GPIO12OKOK (PWM)
SPI (MISO)
D7GPIO13OKOKSPI (MOSI)
D5GPIO14OKOK (PWM)
SPI (SCLK)
D8GPIO15pull-downOK (PWM)
Boot fails if pulled-upSPI (CS)
D0GPIO16no Int.HIGHwake up from deep sleep
A0ADC0AnalogX10-bit ADCinput range of 0 – 1.0V

Leave a Reply

Your email address will not be published. Required fields are marked *

*