Pin	Type	Function	Name	Function
1	P	Ground	GND	Ground
2	P	Power supply.	3.3V	Power supply to ESP32 WROOM32
3	I	Chip-enable signal. Active high.	ESP32_EN	"EN" switch
4	I	GPIO36, SENSOR_VP, ADC_H, ADC1_CH0, RTC_GPIO0	ADC_IN	ADC in (from 12V vehicle power voltage divider)
5	I	GPIO39, SENSOR_VN, ADC1_CH3, ADC_H, RTC_GPIO3	SD_DET	SD Card DETECT
6	I	GPIO34, ADC1_CH6, RTC_GPIO4	SP_INT1	VSPI INT 1
7	I	GPIO35, ADC1_CH7, RTC_GPIO5	SP_INT2	VSPI INT 2
8	I/O	GPIO32, XTAL_32K_P (32.768 kHz crystal oscillator input), ADC1_CH4, TOUCH9, RTC_GPIO9	EXP_1	Expansion GPIO 1
9	I/O	GPIO33, XTAL_32K_N (32.768 kHz crystal oscillator output), ADC1_CH5, TOUCH8, RTC_GPIO8	EXP_2	Expansion GPIO 2
10	I/O	GPIO25, DAC_1, ADC2_CH8, RTC_GPIO6, EMAC_RXD0	CAN_TXD	CAN, tx to transceiver
11	I/O	GPIO26, DAC_2, ADC2_CH9, RTC_GPIO7, EMAC_RXD1	CAN_RXD	CAN, rx from transceiver
12	I/O	GPIO27, ADC2_CH7, TOUCH7, RTC_GPIO17, EMAC_RX_DV	SP_CS2	VSPI CS 2 (MCP2515)
13	I/O	GPIO14, ADC2_CH6, TOUCH6, RTC_GPIO16, MTMS, HSPICLK, HS2_CLK, SD_CLK, EMAC_TXD2	SD_CLK	SD Card CLK
14	I/O	GPIO12, ADC2_CH5, TOUCH5, RTC_GPIO15, MTDI, HSPIQ, HS2_DATA2, SD_DATA2, EMAC_TXD3	SD_DATA2	SD Card DATA2
15	P	Ground	GND	Ground
16	I/O	GPIO13, ADC2_CH4, TOUCH4, RTC_GPIO14, MTCK, HSPID, HS2_DATA3, SD_DATA3, EMAC_RX_ER	SD_DATA3	SD Card DATA3
17	I/O	GPIO9, SD_DATA2, SPIHD, HS1_DATA2, U1RXD	FL_DATA2	SPI flash on ESP-WROOM-32
18	I/O	GPIO10, SD_DATA3, SPIWP, HS1_DATA3, U1TXD	FL_DATA3	SPI flash on ESP-WROOM-32
19	I/O	GPIO11, SD_CMD, SPICS0, HS1_CMD, U1RTS	FL_CS1	SPI flash on ESP-WROOM-32
20	I/O	GPIO6, SD_CLK, SPICLK, HS1_CLK, U1CTS	FL_CLK	SPI flash on ESP-WROOM-32
21	I/O	GPIO7, SD_DATA0, SPIQ, HS1_DATA0, U2RTS	FL_DATA0	SPI flash on ESP-WROOM-32
22	I/O	GPIO8, SD_DATA1, SPID, HS1_DATA1, U2CTS	FL_DATA1	SPI flash on ESP-WROOM-32
23	I/O	GPIO15, ADC2_CH3, TOUCH3, MTDO, HSPICS0, RTC_GPIO13, HS2_CMD, SD_CMD, EMAC_RXD3	SD_CMD	SD Card CMD
24	I/O	GPIO2, ADC2_CH2, TOUCH2, RTC_GPIO12, HSPIWP, HS2_DATA0, SD_DATA0	SD_DATA0	SD Card DATA0
25	I/O	GPIO0, ADC2_CH1, TOUCH1, RTC_GPIO11, CLK_OUT1, EMAC_TX_CLK	ESP32_IO0	"BOOT" switch
26	I/O	GPIO4, ADC2_CH0, TOUCH0, RTC_GPIO10, HSPIHD, HS2_DATA1, SD_DATA1, EMAC_TX_ER	SD_DATA1	SD Card DATA1
27	I/O	GPIO16, HS1_DATA4, U2RXD, EMAC_CLK_OUT	MDM_TXD	UART 2, TX to modem
28	I/O	GPIO17, HS1_DATA5, U2TXD, EMAC_CLK_OUT_180	MDM_RXD	UART 2, RX from modem
29	I/O	GPIO5, VSPICS0, HS1_DATA6, EMAC_RX_CLK	SP_CS1	VSPI CS 1 (MCP2515)
30	I/O	GPIO18, VSPICLK, HS1_DATA7	SP_CLK	VSPI CLK
31	I/O	GPIO19, VSPIQ, U0CTS, EMAC_TXD0	SP_MISO	VSPI MISO
32	-	-	n/a	No connection
33	I/O	GPIO21, VSPIHD, EMAC_TX_EN	SP_CS3	VSPI CS3 (MAX7317 I/O expander)
34	I/O	GPIO3, U0RXD, CLK_OUT2	CSL_TXD	UART 0, TX to console
35	I/O	GPIO1, U0TXD, CLK_OUT3, EMAC_RXD2	CSL_RXD	UART 0, RX from console
36	I/O	GPIO22, VSPIWP, U0RTS, EMAC_TXD1	FL_CS2	SPI to external flash, Chip Select
37	I/O	GPIO23, VSPID, HS1_STROBE	SP_MOSI	VSPI MOSI
38	P	Ground	GND	Ground
39	P	Ground	GND	Ground