Saildrop-os

Saildrop OS is an ESP32 operating system for sailing gauges and tools.

This is a work in progress project, and currently I'm targeting the Waveshare Esp32 with 1.28 inch touch LCD, connected to an NMEA3WIFI multiplexer using wifi.

Supported Devices

Device	Display	Touch	Status
Waveshare ESP32-S3 1.28" Touch LCD	240x240 GC9A01 (SPI)	CST816S	✅ Supported
Waveshare ESP32-S3 4" Touch LCD	480x480 ST7701 (RGB)	GT911	✅ Supported

Customization

The OS is customizable by editing saildrop/conf.h.

Building

https://www.waveshare.com/wiki/ESP32-S3-Touch-LCD-1.28

It provides a package with fixed version libraries, use their tft.

• esp32 version 2.0.12
• lvgl 9.3.0
• tft_espi
• micronmea

https://github.com/lvgl/lvgl/blob/v8.3.11/examples https://docs.lvgl.io/8.4/widgets/extra/index.html

# Build for your board
make compile BOARD=BOARD_<NAME>

# Upload and monitor
make upload
make monitor

Adding Support for a New Device

To add support for a new ESP32 display board, follow these steps:

1. Create a Board Configuration File

Create a new file saildrop/boards/board_<name>.h with hardware-specific definitions:

#ifndef BOARD_<NAME>_H
#define BOARD_<NAME>_H

#define BOARD_NAME "Your-Board-Name"

// Screen dimensions
#define SCREEN_WIDTH  <width>
#define SCREEN_HEIGHT <height>

// Display shape (0 = rectangular/square, 1 = circular/round)
#define DISPLAY_IS_ROUND <0 or 1>

// Display driver selection
#define DISPLAY_DRIVER_SPI      <0 or 1>   // For SPI displays (GC9A01, ST7789, etc.)
#define DISPLAY_DRIVER_RGB      <0 or 1>   // For RGB parallel displays (ST7701, etc.)
#define DISPLAY_USE_TFT_ESPI    <0 or 1>   // Use TFT_eSPI library

// Touch driver selection
#define TOUCH_DRIVER_CST816S    <0 or 1>
#define TOUCH_DRIVER_GT911      <0 or 1>

// Touch I2C pins
#define TOUCH_SDA_PIN   <pin>
#define TOUCH_SCL_PIN   <pin>
#define TOUCH_RST_PIN   <pin or -1 if via IO expander>
#define TOUCH_INT_PIN   <pin>

// LVGL buffer size
#define DRAW_BUF_SIZE   (SCREEN_WIDTH * SCREEN_HEIGHT / 10 * (LV_COLOR_DEPTH / 8))
#define USE_PSRAM_BUFFER <0 or 1>

// DPI for this display
#define DISPLAY_DPI     <dpi>

#endif

2. Register the Board in boards.h

Edit saildrop/boards/boards.h to include your board:

#if defined(BOARD_<NAME>)
    #include "board_<name>.h"
#elif defined(BOARD_LCD_128)
    #include "board_lcd_128.h"
// ... other boards
#endif

3. Create LVGL Configuration (if needed)

For displays with different memory/feature requirements, create lv_conf_<name>.h:

• Adjust LV_MEM_SIZE based on available RAM
• Enable/disable LV_USE_TFT_ESPI based on display driver
• Configure DPI with LV_DPI_DEF

4. Add Display Driver Support (if new driver needed)

If the display uses a driver not yet supported, update saildrop/hal.h:

• Add include for the display library
• Add initialization code in HAL::begin()
• Add flush callback in HAL::initDisplay()

5. Add Touch Driver Support (if new driver needed)

If the touch controller is not yet supported:

1. Create saildrop/drivers/<TouchDriver>.h with the driver implementation
2. Add #define TOUCH_DRIVER_<NAME> option in board config
3. Update saildrop/hal.h to include and initialize the new driver

6. Handle IO Expanders (if present)

Some boards use IO expanders (PCA9557, TCA9554, etc.) for:

• Backlight control
• Display reset
• Touch reset

Add expander initialization in HAL::initIOExpander() if needed.

License

This software is licensed with Apache License 2.0.