JoyPi_Advanced_RGB_Matrix_RP2040

Software for RP2040 on Joy-Pi Advanced with the RGB matrix

Note

This code has dependencies to Adafruit Neopixel.

Pinout

Function	GPIO	Description
Pin to matrix	GPIO 6	LED matrix signal
I2C SDA	GPIO 20	I2C data line
I2C SCL	GPIO 21	I2C clock line

I2C Communictaion Protocol

Byte Offset	Field	Type	Description
0	Command	uint8_t	Reserved/Command prefix
1	ParamCnt	uint8_t	Parameter count (fixed at 0x0B)
2	funcNum	uint8_t	Function code (see table below)
3	pos	uint8_t	LED position index (0-63)
4	r	uint8_t	Red component (0-255)
5	g	uint8_t	Green component (0-255)
6	b	uint8_t	Blue component (0-255)
7	w	uint8_t	White component (0-255)
8	c	uint8_t	Mixed color parameter
9	bright	uint8_t	Global brightness (0-255)
10	first	uint8_t	Starting pixel (for FILL function)
11	count	uint8_t	Pixel count (for FILL function)
12	data	uint8_t	Extended data / Interrupt flag
13	data1	uint8_t	Extended data 2

Function Encoding

Function Codes (FunctionEnum)

Code	Name	Description
0	SHOW	Refresh display (push RAM data to LEDs)
1	SETPIXELCOLOR	Set single pixel color
2	FILL	Fill a range of pixels with color
3	SETBRIGHTNESS	Set global brightness
4	GAMMA8	Read Gamma8 correction table value (Request)
5	GAMMA32	Read Gamma32 correction table value (Request)
6	NUMPIXEL	Read LED count (Request)
7	COLORHSV	Read HSV to RGB conversion value (Request)
8	CLEAR	Clear all pixels
9	SENDDATA2SHOW	Bitmap mode display (8×8 matrix control)
10-15	SENDALLPIXRGB0-5	Bulk pixel data block transfer (32 bytes per block)

Bulk Pixel Data Transfer

For SENDALLPIXRGB0 through SENDALLPIXRGB5 (codes 10-15):

Each command transmits 32 bytes of RGB data

Total of 6 blocks, accumulating 192 bytes (64 pixels × 3 colors)

Upon receiving SENDALLPIXRGB5, the entire matrix automatically refreshes

File Structure

JoyPi_Advanced_RGB_Matrix_RP2040/ ├── rgb_matrix.h # Global header: macros, data structures, definitions ├── matrix_functions.cpp # Control RGB matrix: methods to use teh Adafruit Neopixel code └── rgb_matrix.ino # Main program: initialization, setup of i2c handlers

Key Components

• void i2c_receive_handler(int numBytes) > Method to save data from I2C communication
• void i2c_request_handler() > Method to write requested value to communication
• void matrix_handler(const uint8_t _receivedData[MAX_BUF_LEN]) > Method to execute other methods to manipulate matrix depending on funcNum
• FunctionEnum > Enum holds the encoding of the different function which are possible execute
• TransferData > Class to hold all relevant read data from I2C communication
• RGBMatrix > Class to manipulate matrix and uses Adafruit Neopixel