Video about ESP-LCD

Hi,

I’ve just found this video from Espressif about their new ESP-LCD board that uses LVGL.
I thought it might be interesting for some people here. :slight_smile:

https://www.youtube.com/watch?v=1LNdpcw5t0Q

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This is very interesting as ESP32 is not usually used with such large displays. What we typically see is ILI9431 displays (320x240) wired via SPI. Using anything larger with ESP32 has always been a pain since ESP32 lacks suitable parallel outputs. I’m aware of people abusing the I2S peripheral to interface some displays and even a project interfacing the QSPI peripheral (intended for flash memory) to an FPGA driving the display, but none of those seemed dependable well-performing solutions. Am I missing something?

Do you know how this 800x480 display is connected?
And what frame rates can be expected?

This LCD uses RM68120 as its display IC and FT5436 as its touch IC. The display IC of the LCD used in ESP32-S2-HMI-DevKit-1 has been configured as 16-bit 8080 parallel communication, with totalled 18 GPIOs used, i.e., 16 data lines (LCD_D0…LCD_D15), a bit clock signal (LCD_WR) and a data/command distinguish signal (LCD_DC/LCD_RS).

Source: https://github.com/espressif/esp-dev-kits/blob/master/esp32-s2-hmi-devkit-1/docs/ESP32-S2-HMI-DevKit-1_Display_en.md

I could not find a schematic of the board unfortunately. This doesn’t sound very fast though.

Note that ESP32-S2 is different from “normal” ESP32. See here and here.

Seemingly the ESP-LCD kit doesn’t use it but ESP32-S2 has an LCD periphery to drive displays “natively”.

Thank you, I was not aware of that.

As I now found out, the ESP32-S2 (unlike the ESP32) can communicate in 8080 mode. But what’s even more interesting is that it can apparently drive a controller-less display directly (i.e. it can generate VSYNC, HSYNC and DE signals and continuously refresh the LCD with the correct timing, all via DMA). See section 8.4.8 in the Technical Reference Manual.

That is a great milestone because controller-less displays are much cheaper than those with a display controller chip (an SSD1963 cost $6.50 last time I checked, just the chip), and controller-less LCDs from different manufacturers are essentially all controlled the same way, which makes a project less dependent from a single supplier, and that is a big plus if you want to make actual products.

I wish Espressif had better documentation and examples. I really want to see this working with LVGL!

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