ESP32 How to use with devices

1 x ESP32 monitor/controller

3.3V ESP32 logic and development board ($7.38)

See pin outs below

Project
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ESP32D Pin mapping
(click table for installable program guide code)

Left side pins (from top to bottom)

| Label | GPIO Number   | Notes
| ----- | ------------- | -------------------
| EN    | Reset pin     | Not GPIO
| VP    | GPIO36        | Input-only (ADC)
| VN    | GPIO39        | Input-only (ADC)
| D34   | GPIO34        | Input-only (ADC)
| D35   | GPIO35        | Input-only (ADC)
| D32   | GPIO32        | ADC, can be input
| D33   | GPIO33        | ADC, can be input
| D25   | GPIO25        | DAC, can be output
| D26   | GPIO26        | DAC, can be output
| D27   | GPIO27        | ADC, can be input
| D14   | GPIO14        | PWM, SPI, I2C
| D12   | GPIO12        | PWM, SPI, I2C
| D13   | GPIO13        | PWM, SPI, I2C
| GND   | Ground        | Ground pin
| VIN   | Input voltage | Power in 5V in/out
|       |               | out =< 500 ma

Right side pins (from top to bottom)

| Label | GPIO Number   | Notes
| ----- | ------------- | ---------------
| D23   | GPIO23        | PWM, SPI
| D22   | GPIO22        | PWM, SPI, I2C
| TXD   | GPIO1         | UART0 TX
| RXD   | GPIO3         | UART0 RX
| D21   | GPIO21        | PWM, I2C
| D19   | GPIO19        | PWM, SPI
| D18   | GPIO18        | PWM, SPI
| D5    | GPIO5         | PWM, SPI
| TX2   | GPIO17        | UART2 TX
| RX2   | GPIO16        | UART2 RX
| D4    | GPIO4         | PWM, SPI
| D2    | GPIO2         | Built-in LED, some
| D15   | GPIO15        | PWM, SPI
| GND   | Ground        | Ground pin
| 3V3   | 3.3V Power    | Power pin max 300ma

Notes:

    Pins VP (GPIO36), VN (GPIO39), D34 (GPIO34), D35 (GPIO35), D32, and D33 are ADC-capable input-only pins.
    They cannot be used as digital outputs.

    Pins like D25 and D26 have DAC (digital-to-analog converter) capability.

    Pins labelled TXD/RXD correspond to the UART serial pins.

    Pins like D2 (GPIO2) often have an onboard LED on some ESP32 boards.

    EN is not a GPIO pin; it's the enable (reset) pin.

Summary usage:

    Use the GPIO numbers in code, e.g., digitalRead(34) or digitalWrite(2, HIGH).

    Do not to use input-only ADC pins as outputs.

    You can use most of the pins for PWM, SPI, I2C, UART, or digital IO as shown.

    max GPIO output 12 ma per pin, Use resistors when driving LEDs (eg. 220-330 Ohms). max total 120 ma

    Input consumption ~50 µA typical

    No pin tolerates < 0 V or > 3.6 V