docs/reference/hardware/controller-pinout.md

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Controller GPIO Pinout	1.0

Controller GPIO Pinout

GPIO pin assignments for the ClearGrow Controller (ESP32-S3 with Waveshare 4.3" RGB LCD).

Source of Truth: /opt/repos/controller/main/pin_config.h

GPIO Pin Allocation Table

GPIO	Function	Interface	Notes
0	LCD_B2	RGB	Blue bit 2 (strapping pin)
1	RESERVED	—	Reserved (previously NFC_CS)
2	RESERVED	—	Reserved (previously NFC_IRQ)
3	TOUCH_INT	GPIO	Touch interrupt (input)
4	LCD_VSYNC	RGB	LCD vertical sync
5	LCD_HSYNC	RGB	LCD horizontal sync
6	LCD_G0	RGB	Green bit 0
7	LCD_R4	RGB	Red bit 4
8	USB_VBUS_DETECT	GPIO	USB power detection
9	LCD_G2	RGB	Green bit 2
10	LCD_G3	RGB	Green bit 3
11	LCD_G4	RGB	Green bit 4
12	LCD_G5	RGB	Green bit 5
13	LCD_B0	RGB	Blue bit 0
14	LCD_B1	RGB	Blue bit 1
15	LCD_R3	RGB	Red bit 3
16	LCD_R2	RGB	Red bit 2
17	LCD_R1	RGB	Red bit 1
18	LCD_R0	RGB	Red bit 0
19	TOUCH_SDA	I2C	GT911 touch data
20	TOUCH_SCL	I2C	GT911 touch clock
21	LCD_PCLK	RGB	LCD pixel clock
35	SPI_MOSI	SPI2	SD card data out
36	SPI_SCLK	SPI2	SD card clock
37	SPI_MISO	SPI2	SD card data in
38	LCD_BACKLIGHT	LEDC	PWM backlight control
39	SD_CS	SPI2	SD card chip select
40	RCP_RESET	GPIO	nRF52840 RCP reset
41	STATUS_LED	GPIO	Status LED output
43	RCP_TX	UART	ESP TX → nRF RX
44	RCP_RX	UART	ESP RX ← nRF TX
45	LCD_DE	RGB	LCD data enable
46	LCD_G1	RGB	Green bit 1 (strapping)
47	LCD_B3	RGB	Blue bit 3
48	LCD_B4	RGB	Blue bit 4

Pin Configuration Header

// main/pin_config.h
#ifndef PIN_CONFIG_H
#define PIN_CONFIG_H

// === RGB Display Interface ===
#define PIN_LCD_DE          45
#define PIN_LCD_VSYNC       4
#define PIN_LCD_HSYNC       5
#define PIN_LCD_PCLK        21

// Red channel (5 bits)
#define PIN_LCD_R0          18
#define PIN_LCD_R1          17
#define PIN_LCD_R2          16
#define PIN_LCD_R3          15
#define PIN_LCD_R4          7

// Green channel (6 bits)
#define PIN_LCD_G0          6
#define PIN_LCD_G1          46
#define PIN_LCD_G2          9
#define PIN_LCD_G3          10
#define PIN_LCD_G4          11
#define PIN_LCD_G5          12

// Blue channel (5 bits)
#define PIN_LCD_B0          13
#define PIN_LCD_B1          14
#define PIN_LCD_B2          0
#define PIN_LCD_B3          47
#define PIN_LCD_B4          48

#define PIN_LCD_BACKLIGHT   38

// === Touch Controller (GT911) ===
#define PIN_TOUCH_SDA       19
#define PIN_TOUCH_SCL       20
#define PIN_TOUCH_INT       3
#define PIN_TOUCH_RST       -1   // Not connected

// === SPI Bus (SD card) ===
#define PIN_SPI_MOSI        35
#define PIN_SPI_MISO        37
#define PIN_SPI_SCLK        36

#define PIN_SD_CS           39

// Reserved pins (previously NFC)
// #define PIN_NFC_CS          1
// #define PIN_NFC_IRQ         2

// === Thread RCP (nRF52840 via UART) ===
#define PIN_RCP_TX          43
#define PIN_RCP_RX          44
#define PIN_RCP_RESET       40

// === Other ===
#define PIN_USB_VBUS_DETECT 8
#define PIN_STATUS_LED      41

// === I2C/SPI Frequencies ===
#define I2C_TOUCH_FREQ_HZ   400000
#define SPI_BUS_FREQ_HZ     10000000

#endif // PIN_CONFIG_H

Interface Groups

RGB LCD (16-bit RGB565)

The display uses a 16-bit parallel RGB interface:

Signal	GPIO	Description
DE	45	Data enable
VSYNC	4	Vertical sync
HSYNC	5	Horizontal sync
PCLK	21	Pixel clock
R[4:0]	7, 15-18	Red channel (5 bits)
G[5:0]	6, 9-12, 46	Green channel (6 bits)
B[4:0]	0, 13-14, 47-48	Blue channel (5 bits)
Backlight	38	PWM brightness control

Touch Controller (GT911)

Signal	GPIO	Description
SDA	19	I2C data
SCL	20	I2C clock
INT	3	Touch interrupt
RST	-1	Not connected

I2C frequency: 400 kHz

SPI Bus (SD Card)

SPI2 used for SD card storage:

Signal	GPIO	Description
MOSI	35	Data out
MISO	37	Data in
SCLK	36	Clock
SD_CS	39	SD card chip select

Note: GPIO 1 and 2 are reserved (previously used for NFC reader, now removed)

Thread RCP (nRF52840)

Signal	GPIO	Description
TX	43	ESP32 TX → nRF RX
RX	44	ESP32 RX ← nRF TX
RESET	40	nRF reset control

Status & Power

Signal	GPIO	Description
STATUS_LED	41	Status indicator LED
USB_VBUS_DETECT	8	USB power detection

Strapping Pin Notes

GPIO	Boot Requirement	Usage
0	Pull-up (normal boot)	LCD_B2 - safe after boot
45	Pull-down (3.3V VDD_SPI)	LCD_DE - safe after boot
46	Pull-down (normal boot)	LCD_G1 - safe after boot

GPIO 0, 45, and 46 are strapping pins. They affect boot behavior but can be used for LCD signals after boot completes.

Related Documents

• Controller PCB
• Controller Power
• Components