Display hats

There are a number of Raspberry Pi HAT displays available.

Color 1.44 128x128 display (ST7735S)

This HAT is listed as Waveshare 1.44inch LCD Display HAT for Raspberry Pi 128x128 with Embedded Controller Communicating via SPI Interface (Amazon, Waveshare).

• LCD display HAT for Raspberry Pi, 1.44inch diagonal, 128x128 pixels, with embedded controller, communicating via SPI interface.
• 1x joystick (5-position), 3x pushbuttons
• RGB, 65K color
• ST7735S ("green tab")
• Manual

To use this display, use the Adafruit_ST7735_RK library. The Adafruit_ST7735_RK github contains a README and example code. The pi-HAT example works with this board.

The initialization code is typically:

#define TFT_CS        A6
#define TFT_RST       A5
#define TFT_DC        D22

Adafruit_ST7735 tft = Adafruit_ST7735(&SPI, TFT_CS, TFT_DC, TFT_RST);

This sample uses the display and also handles debouncing the buttons.

As of Device OS 5.9.0, it's not possible to read IOEX_PB7 from user firmware, so you won't be able to interpret the joystick right button.

SSD1305 Monochrome OLED

This HAT is listed as 2.23 inch OLED Display HAT for Raspberry Pi 2B/3B/4B/Zero/Zero W Jetson Nano 128×32 Pixels SPI/I2C Interface (Amazon, Waveshare).

To use this display with the Muon, use the Particle port of the Adafruit SSD1305 library. It's in the community libraries as Adafruit_SSD1305_RK and the Adafruit_SSD1305_RK Github contains the source and README. The example pi-hat works with this display.

The important parameters for this display are:

#define OLED_CS A6 
#define OLED_DC D25
#define OLED_RESET D22

Adafruit_SSD1305 display(128, 32, &SPI, OLED_DC, OLED_RESET, OLED_CS, 7000000UL);