Display (MIPI-DSI)

The ESP32-P4 integrates a MIPI-DSI host controller capable of driving high-resolution LCD panels. This guide covers supported displays, hardware setup, and getting a graphical interface running with LVGL or the Arduino GFX library.

Display interface overview

The board’s MIPI-DSI controller provides:

Specification	Value
Interface	2-lane MIPI D-PHY v1.1
Maximum bandwidth	1.5 Gbps per lane
Color formats	RGB888, RGB666, RGB565
Pixel processing	Integrated PPA (Pixel Processing Accelerator)
DMA	2D-DMA for efficient framebuffer transfers
JPEG decode	Hardware-accelerated, 1080P at 30fps

Supported screens

Waveshare offers several MIPI-DSI panels tested with this board:

Screen size	Resolution	Touch	Notes
5.0”	800 x 480	Capacitive	Compact, good for handheld
7.0”	800 x 480	Capacitive	Most common for prototyping
8.0”	800 x 1280	Capacitive	Portrait orientation default
10.1”	800 x 1280	Capacitive	Largest supported size

Note

Third-party MIPI-DSI panels may work if they are 2-lane compatible, but Waveshare only provides tested drivers for the screens listed above.

Hardware connection

1. Power off the board (disconnect USB).

2. Connect the DSI ribbon cable from the display to the board’s MIPI-DSI FPC connector. The cable tab faces away from the PCB — align the contacts and press the connector latch down firmly.

3. If your display has a separate touch connector (I2C), connect it to the corresponding header on the board.

4. Reconnect USB power. The backlight should illuminate (the screen may show noise until firmware initializes it).

Caution

FPC connectors are fragile. Do not force the ribbon cable. If it does not slide in smoothly, verify the orientation and that the latch is fully open before inserting.

Setting up LVGL (ESP-IDF)

LVGL v9.3.0 is the recommended GUI framework for ESP-IDF projects. It provides a rich widget library, animation support, and efficient rendering that takes advantage of the ESP32-P4’s PPA and 2D-DMA.

1. Create or open an ESP-IDF project targeting ESP32-P4.

2. Add the LVGL component to your project. In your project directory:

   idf.py add-dependency "lvgl/lvgl^9.3.0"

3. Add the display driver component. Waveshare’s demo package includes a pre-configured BSP (Board Support Package) with panel initialization for each supported screen size.

4. Configure LVGL via menuconfig:

   idf.py menuconfig

   Navigate to Component config > LVGL configuration and set:

   • Display resolution to match your panel
   • Color depth (16-bit RGB565 for performance, 24-bit RGB888 for quality)
   • Enable GPU acceleration if available in the menu

5. In your application code, initialize the display driver and LVGL:

   #include "lvgl.h"
   #include "bsp/esp-bsp.h"
   
   void app_main(void)
   {
       bsp_display_start();
       bsp_display_backlight_on();
   
       lv_obj_t *label = lv_label_create(lv_scr_act());
       lv_label_set_text(label, "ESP32-P4 Display Ready");
       lv_obj_align(label, LV_ALIGN_CENTER, 0, 0);
   }

6. Build and flash:

   idf.py build
   idf.py -p /dev/ttyUSB0 flash monitor

Setting up GFX Library (Arduino)

For Arduino projects, GFX_Library_for_Arduino provides a simpler API for basic drawing operations.

1. Ensure you have completed the Arduino setup, including installing GFX_Library_for_Arduino v1.6.0 and the displays library.

2. Open the appropriate example from the demo package for your screen size.

3. The display is initialized through the displays library which handles DSI lane configuration and panel timing for each supported screen.

4. Basic drawing example:

   #include <Arduino_GFX_Library.h>
   
   // Display instance is configured by the displays library
   extern Arduino_GFX *gfx;
   
   void setup() {
     gfx->begin();
     gfx->fillScreen(BLACK);
     gfx->setTextColor(WHITE);
     gfx->setTextSize(3);
     gfx->setCursor(10, 10);
     gfx->println("Hello ESP32-P4!");
   }
   
   void loop() {
     // Your drawing code here
   }

5. Upload to the board and verify the display shows your output.

Performance considerations

The ESP32-P4’s hardware acceleration pipeline significantly improves rendering performance:

• PPA (Pixel Processing Accelerator): Handles color space conversion, scaling, and rotation in hardware. LVGL can offload these operations automatically when the PPA driver is enabled.
• 2D-DMA: Transfers framebuffer data to the DSI controller without CPU involvement, freeing the RISC-V cores for application logic.
• JPEG decoder: Decodes JPEG images in hardware at up to 1080P 30fps, useful for photo galleries or splash screens.

For best frame rates on high-resolution panels, use RGB565 color depth and enable double buffering in LVGL’s configuration.

Application examples

Smart home panel

LVGL widgets for thermostat control, lighting scenes, and security camera feeds on a 7” or 10.1” touchscreen.

Industrial HMI

Process monitoring dashboards with charts, gauges, and alarm indicators. The ESP32-P4’s real-time capabilities suit factory floor use.

Vending machine UI

Product selection menus with images (JPEG-decoded in hardware), payment status, and animated transitions.

Kiosk / info display

Digital signage with timed content rotation, touch navigation, and network-sourced content via WiFi 6.

Further reading

• LVGL documentation — full widget and driver reference
• Espressif MIPI-DSI driver API
• Waveshare demo package — pre-built display examples for each screen size