06

7.0

ESP32 Peripherals

Table 2 – Peripherals

Figure 3 – External RTC crystal circuits

† These are hardware limits, the micropython firmware may impose its own limits.

* Requires an external CAN bus transceiver, we recommend the SN65HVD230 from Texas Instruments.

For a more detailed description of the ESP32 peripherals

along with peripherals not currently supported by our

firmware, please check the ESP32 datasheet.

7.1

RTC

Our modules by default all use the internal RC oscillator

at 150kHz for the RTC. If you require better accuracy/

stability you can connect a 32.768 kHz crystal (or TCXO)

externally on pins P19 and P20 (or P19 for a TXCO)

Peripheral

Count

Pins

UART

3

Remappable to any GPIO.

Note: P13–18 can only be mapped to RX or CTS since they are input only.

I2C

2

Remappable to any GPIO except P13–18 since they are input only and I2C is bi–directional.

SPI

3

Remappable to any GPIO.

Note: P13–18 can only be mapped to MISO since they are input only.

CAN*

1

Remappable to any GPIO.

Note: P13–18 can only be mapped to RX since they are input only.

JTAG

1

TDO = P4, TDI = P9, TCK = P10, TMS = P24

PWM

1

All GPIO except P13–18 which are input only

ADC

18

Fixed mapping, see Table 1, Only ADC 1 is supported in our micropython firmware.

DAC

2

Only available on P21 and P22

SD

1

DAT0 = P8, SCLK = P23, CMD = P4