Gevino tft - samd21 - ra8876

Hello Comunity

I’m making this display:

48 Mhz, 32-bit ARM Cortex - M0+ processor. Flash 256KB, RAM 32K
7” Capacitive Touch 1024x600
Isolated Input, Output, analog, module.
RA8876 Controller on SPI bus

I would try this library, but I have many doubts.

The RA8876 has an accelerator that makes it very fast, drawing primitives, it has a DMA to draw proportional fonts and images from a Flash chip connected to it.

Set pixel is very slow.
Copy image from SD, require 20 Seconds.
Write text from CPU Flas, require 3 Seconds

It may also be that we can improve, but do not know by how much.

If you chose LittlevGL, you wouldn’t be able to make use of the acceleration for drawing primitives, but you might be able to utilize DMA to transfer the bitmap in RAM that the library gives you to the display.

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I can put on DMA Flash all the Object of library of all the theme ?
And use Flash Font ?
There are 2 Serial Flash on the board.

No one has had experience with RA8876 ?
I’m not a software expert, I’m hardware technical.

No. We compose a bitmap of the display in RAM and then flush it to the display. You will not be drawing directly from flash.

print picture from flash to TFT on 250mS

print same picture on 150mS

TFT is 1024x600 pixel

With this speed, the net effect may be nice?
I do not mean scrolling page, but at least the slide transition and movement of objects.