ESP32-S3 LCD Intel 8080 bus read

[daniSi]

Dear,

I have successfully implemented the lcd example with intel 8080 bus for a ili9488 controller. I would now additionally need a read capability. I started to modify the esp_lcd_panel_io_i80.c file but I am not quite sure if its even possible to accomplish this with use of the functions found in lcd_ll.h?

best regards!

[ESP_Sprite]

Likely not, the LCD logic is write-only. You could bitbang the read configuring the bus as GPIOs, though.

[daniSi]

I tried to follow your suggestion with implementing the bitbang method. I have now managed to control the CS and RD pin separate from lcd library and to match all the pin states as the LCD driver datasheet requires. Also in the ESP LCD library I have changer the data pins from output->input/output.

The problem is that when i generate the clock signal on the RD pin, on the data line the state always remains "0". Could be this due to the ESP LCD library which holds the pins to state "0"? Would the pins have to be configured differently?

Here is also the screenshot of the output

[ESP_Sprite]

You would have to reconfigure those pins as GPIOs and inputs, yes.