2. Masterboard

2.1 Layout and Components

Component	Description
ESP32-WROOM-32	A module with ESP32 at its core. For more information, see ESP32-WROOM-32 Datasheet
ON-OFF Switch (S1)	Switch ON/OFF the board.
ENABLE Button (SW1)	Reset button.
BOOT Button (SW2)	Download button. Holding down BOOT and then pressing ENABLE initiates Firmware Download mode for downloading firmware through the serial port
USB-C Port (J1)	USB interface. Power supply for the board as well as the communication interface between a computer and the ESP32-WROOM-32 module.
I/O Pins (J2, J8)	Most of the pins on the ESP module are broken out to the pin headers on the board. You can program ESP32 to enable multiple functions such as PWM, ADC, DAC, I2C, I2S, SPI etc.
5V Power On LED	Turns on when the USB or an external 5V power supply is connected to board
Sensor Ports (J5, J6, J9, J10)	Connect sensor modules to the board. Contains the necessary pins to control the sensor
Master-Slave Connector Port	Connect master board to slave board.

2.2 Pin Layout

2.3 Pin Definition

J5 (Sensor Port 1)

No.	Name	Type	Function
1	ESPIO17	I/O	GPIO17, HS1_DATA5, U2TXD, EMAC_CLK_OUT_180
2	ESPIO16	I/O	GPIO16 , HS1_DATA4, U2RXD, EMAC_CLK_OUT
3	GND	P	Ground
4	3V3	P	Vout

J6 (Sensor Port 2)

No.	Name	Type	Function
1	ESPIO19	I/O	GPIO19, VSPIQ, U0CTS, EMAC_TXD0
2	ESPIO18	I/O	GPIO18, VSPICLK, HS1_DATA7
3	GND	P	Ground
4	3V3	P	Vout

J9 (Sensor Port 3)

No.	Name	Type	Function
1	ESPIO25	I/O	GPIO25, DAC_1, ADC2_CH8, RTC_GPIO6, EMAC_RXD0
2	ESPIO23	I/O	GPIO23, VSPID, HS1_STROBE
3	GND	P	Ground
4	3V3	P	Vout

J10 (Sensor Port 4)

No.	Name	Type	Function
1	ESPIO27	I/O	GPIO27, ADC2_CH7, TOUCH7, RTC_GPIO17, EMAC_RX_DV
2	ESPIO26	I/O	GPIO26, DAC_2, ADC2_CH9, RTC_GPIO7, EMAC_RXD1
3	GND	P	Ground
4	3V3	P	Vout

J13

No.	Name	Type	Function
1	5V	P	Vin
2	MOSI	SPI	VSPID
3	GND	P	Ground
4	MISO	SPI	VSPIQ
5	SCK	SPI	VSPICLK
6	CS	SPI	VSPICS0

J7

No.	Name	Type	Function
1	RX	I/O	GPIO3, U0RXD, CLK_OUT2
2	TX	I/O	GPIO1, U0TXD, CLK_OUT3 , EMAC_RXD2

J8 (Breakout Pin)

No.	Name	Type	Function
1	ESPIO36	I	GPIO36, ADC1_CH0, S_VP
2	ESPIO27	I/O	GPIO27, ADC2_CH7, TOUCH7, RTC_GPIO17, EMAC_RX_DV
3	ESPIO26	I/O	GPIO26, ADC2_CH9, DAC_2, RTC_GPIO7, EMAC_RXD1
4	ESPIO25	I/O	GPIO25, ADC1_CH8, DAC_1, RTC_GPIO6, EMAC_RXD0
5	ESPIO	I/O	GPIO23, VSPID, HS1_STROBE
6	ESPIO	I/O	GPIO22, VSPIWP, U0RTS, EMAC_TXD1, SCL
7	ESPIO	I/O	GPIO21, VSPIHD , EMAC_TX_EN, SDA
8	ESPIO	I/O	GPIO19 , VSPIQ, U0CTS, EMAC_TXD0
9	ESPIO	I/O	GPIO18 , VSPICLK, HS1_DATA7
10	ESPIO	I/O	GPIO17 , HS1_DATA5, U2TXD, EMAC_CLK_OUT_180

J2 (Breakout Pin)

No.	Name	Type	Function
1	ESPIO16	I	GPIO16 , HS1_DATA4, U2RXD, EMAC_CLK_OUT
2	ESPIO15	I/O	GPIO15, ADC2_CH3, TOUCH3, MTDO, HSPICS0, RTC_GPIO13, HS2_CMD, SD_CMD, EMAC_RXD3
3	ESPIO14	I/O	GPIO14, ADC2_CH6, TOUCH6, RTC_GPIO16, MTMS, HSPICLK, HS2_CLK, SD_CLK, EMAC_TXD2
4	ESPIO13	I/O	GPIO13, ADC2_CH4, TOUCH4, RTC_GPIO14, MTCK, HSPID, HS2_DATA3, SD_DATA3, EMAC_RX_ER
5	ESPIO12	I/O	GPIO12, ADC2_CH5, TOUCH5, RTC_GPIO15, MTDI, HSPIQ, HS2_DATA2, SD_DATA2, EMAC_TXD3
6	ESPIO5	I/O	GPIO5, VSPICS0, HS1_DATA6, EMAC_RX_CLK
7	ESPIO4	I/O	GPIO4, ADC2_CH0, TOUCH0, RTC_GPIO10, HSPIHD, HS2_DATA1, SD_DATA1, EMAC_TX_ER
8	ESPIO2	I/O	GPIO2,ADC2_CH2, TOUCH2, RTC_GPIO12, HSPIWP, HS2_DATA0, SD_DATA0
9	ESPIO0	I/O	GPIO0, ADC2_CH1, TOUCH1, RTC_GPIO11, CLK_OUT1, EMAC_TX_CLK
10	ESP_EN	P	Module-enable signal. Active high.

J12

No.	Name	Function
1	HEADER TO SLAVEBOARD	Connect masterboard to slaveboard

NOTE: You might have noticed that some pin in the sensor port and the breakout pin have the same number. They are the same pin essentially which means both pins with the same number will be giving the same output.

2.4 Masterboard Dimensions

Length	100mm
Width	100mm
Height (bottom to highest point)	35mm