Advice on adding a new QSPI panel

[Shadowtrance]

Messing around with the QSPI branch trying to add a new panel / screen config but it seems to be way above my pay grade and I can't figure out where to go from here tbh.

It compiles and "seems" to sort of wake the screen but i get no output. I copied another panel that was a similar setup and eyeballed the hell out of Arduino_GFX to try and figure out what's going on (it works with that library).

I'm just banging my head against a wall atm it seems so thought I'd see if anyone can help get it going.

Screen in question is the JC3248W535EN with the AXS15231B controller.

Here's a mess of things I've put together. https://gist.github.com/Shadowtrance/d69e91671e1b77b7c66624279decc71b

[tobozo]

hi,

The QSPI branch was an attempt to integrate changes from a qspi-dedicated fork but it is based on older versions of LovyanGFX and esp-idf core. This branch is kept as is because the originating fork has been deleted.

arduino-esp32 3.1.x was supposed to get native support for QSPI through the SPI library, but it hasn't happened yet.

Arduino_GFX is currently the best model to follow because it uses esp-idf functions instead of trying to inherit from arduino-esp32 SPI API.

[Shadowtrance]

So qspi is a no go atm with LGFX?
Or is my config just not correct in some way? (highly likely)

Guess I'll have to wait for proper qspi support or figure out how to adapt the project i wanted to use which uses LGFX (TFT ESPI) functions to work which I don't think Arduino GFX has. :(

Thanks for the reply. :)

[tobozo]

your config looks correct, but Bus_QSPI just doesn't init, as you can see here Bus_QSPI calls initQuad():

https://github.com/lovyan03/LovyanGFX/blob/QSPI/src/lgfx/v1/platforms/esp32/Bus_QSPI.cpp#L148

however the bus initialization code block is commented out, waiting for espressif to have SPI.begin() handle QSPI:

https://github.com/lovyan03/LovyanGFX/blob/QSPI/src/lgfx/v1/platforms/esp32/common.cpp#L554-L566

you can try uncommenting those lines as a start, this is where I stopped testing:

https://github.com/lovyan03/LovyanGFX/blob/QSPI/src/lgfx/v1/platforms/esp32/common.cpp#L563-L566

[Shadowtrance]

hmm that didn't seem to make a difference.
I did however get "some" more life out of it after changing some of the init commands after looking at the https://github.com/esp-arduino-libs/ESP32_Display_Panel AXS15231B branch. But what flashes i do see appear to be partially off screen which is kinda weird. Running PDQgraphicstest.

Setting cfg.spi_mode to 3 results in backlight on but no other screen life, cfg.spi_mode 1 and 2 result in the partial life above.

It's fun tinkering with things and making even a tiny bit of progress. haha

[Shadowtrance]

So after some messing around with this and arduino gfx it seems the key to success is the "canvas (framebuffer i guess?)" thing arduino gfx uses.
I disabled the canvas and it acted exactly the same as with lgfx mentioned above. (so just using the qspi bus and panel controller type)
Haven't looked any further yet to see if lgfx has anything similar.
Back to digging around code. :)

[tobozo]

I'm not sure what that canvas/framebuffer has to do with QSPI displays or why/if/when it is required, will RTFM 🤣

LGFX_Sprite class sounds like a good candidate for a canvas but it may be too much for a framebuffer.

Maybe the SpriteBuffer class would be a good fit?

Or maybe a framebuffer=ps_malloc( width*height*bpp ) will be enough as a start.

I'm still waiting for my QSPI devices to be delivered so I can only help with theory, for now 😊

[Shadowtrance]

Yeah I'm sure either tbh. I just know it works lol
And for this particular display/controller it is set up like this in arduino gfx (can also see how it's in done in their PDQ Graphics Test example with the included files.)

Arduino_DataBus *bus = new Arduino_ESP32QSPI(45 /* CS */, 47 /* SCK */, 21 /* D0 */, 48 /* D1 */, 40 /* D2 */, 39 /* D3 */);
Arduino_GFX *g = new Arduino_AXS15231B(bus, GFX_NOT_DEFINED /* RST */, 0 /* rotation */, false /* IPS */, 320 /* width */, 480 /* height */);
#define CANVAS
Arduino_Canvas *gfx = new Arduino_Canvas(320 /* width */, 480 /* height */, g, 0 /* output_x */, 0 /* output_y */, 0 /* rotation */);

Then after that instead of calling tft.whatever like you do with LFGX or TFT_eSPI you call gfx->whatever.... and it does stuff.

[tobozo]

At this stage it may be interesting to know what kind of psram the device is using.

From what I understood so far:

• That QSPI+framebuffer operating mode implies that spiram freq >= bus freq, spiram size >=320*480*4 bytes, and spiram type = quad|octal spi.
• Alternatively, esp32 devices with slower psram (or without psram) would need to use MIPI DSI mode instead

[Shadowtrance]

I think i linked some info regarding this screen in the QPSI / MIPI discussion you made but it's using 8M OPI (octal spi?) psram according to the arduino settings they say to use in the getting started guide.