eLCDIF "Smart" Display Configuration

[nmeltzer]

Hello,

I have a display driven by the ILI9488 that is connected to the i.MX RT1064. I am using the eLCDIF module to drive ENABLE, HSYNC, VSYNC, DOTCLK, and DB[17:0]. 

However, I believe the ILI9488 falls into the "smart" display catagory mentioned in "Chapter 35: Enhanced LCD Interface" of the imx reference manual.

To this end, in order to use the RGB interface with the ILI9488, the ILI9488 must be configured using control commands. I am wondering how this is meant to be done.

The method that immediately occurs to me is:

1. Mux all LCD pins as GPIO.
2. Bitbang LCD configuration using D/CX, RDX, WRX, D[7:0] pins
3. Mux all necessary pins back to eLCDIF peripheral
4. Start eLCDIF peripheral and use RGB interface.

I am wondering if this is the intended flow.

Chapter 35 also mentions using APBDMA descriptor chains to interface with "smart" displays, but this is the only place that APBDMA is mentioned, so I am wondering if there is an application note that I am missing.

A related (but less important) question is whether or not it would be possible to use the GRAM onboard the ILI9488 as a framebuffer via DMA operations.

Thank you for your time,

Noah

[kerryzhou]

Hi @nmeltzer ,

  I checked the ILI9488 datasheet:

 https://www.hpinfotech.ro/ILI9488.pdf

Seems this is the MIPI interface, not the LCD parallel interface, so it can't be supported in the RT1060 eLCD interface, as that is the parallel interface.

  You can refer to this community post:

https://community.nxp.com/t5/i-MX-RT/imxrt1062-pxp-rotation-with-non-screen-sized-buffer/td-p/158929...

maybe you need to use the flexIO with 8080 to driver it.

you can refer to this application note:

https://www.nxp.com/docs/en/application-note/AN5313.pdf

Wish it helps you!

Best Regards,

Kerry