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Critique my first PCB
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carl0s:
Same thing is now super fast compared to before.
This is mostly down to CPU DCache and CPU ICache though. The DMA2D made some improvement before the CPU caches were enabled, but nothing like the same improvement that those caches made. I think this simple text demo isn't the best thing to benchmark DMA2D. That's more for shifting large blocks of pixel bytes. Anyway the DMA2D stopped hanging the system once I ticked the box to enable the global interrupt under NVIC. Another thing to read up on .. ;)

http://www.internetsomething.com/lcd/big_numbers_superfast_with_cpudcache_cpuicache.mp4
luiHS:
 
Do you know what the IC controller chip is on your round screen? I would like to start doing my tests with the same screen model. I have here three different models of screens, two are octagonal and one totally round (2.1 inches).

The controller chips are ST7796S, ST7701S and HX8379-C, fortunately I have the data sheet of the three, the one of the HX8379-C was quite difficult to get.

2.4 inches, octagonal outline, ST7796S controller chip, 320x320 pixel, Active area 60mm, TE available
2.47 inches, octagonal outline, HX8379-C controller chip, 480x480 pixel, Active area 62mm, TE not available
2.1 inches, round outline, ST7701S controller chip, 480x80 pixel, Active Area 53mm, TE available
carl0s:

--- Quote from: luiHS on August 08, 2019, 03:09:24 pm ---
Do you know what the IC controller chip is on your round screen? I would like to start doing my tests with the same screen model. I have here three different models of screens, two are octagonal and one totally round (2.1 inches).

The controller chips are ST7796S, ST7701S and HX8379-C, fortunately I have the data sheet of the three, the one of the HX8379-C was quite difficult to get.

2.4 inches, octagonal outline, ST7796S controller chip, 320x320 pixel, Active area 60mm, TE available
2.47 inches, octagonal outline, HX8379-C controller chip, 480x480 pixel, Active area 62mm, TE not available
2.1 inches, round outline, ST7701S controller chip, 480x80 pixel, Active Area 53mm, TE available

--- End quote ---

Mine is the 2.4" which the manufacturer describes as 3.4", with ST7796S and 17 pin 0.3mm FPC connector, no touch.

Please could you post pictures of all 3 of your screens? Would be interesting to see the differences.

Also, TE can be sent as a MIPI packet, without its own pin. maybe that's what your 2.47" can do ?
carl0s:
If your 2.47" screen is the one I've just found on the internet, then it's not MIPI-DSI is it? It has SPI and parallel RGB

If that's correct, then maybe you just use VSYNC.
https://kingtechgroup.en.alibaba.com/product/60791460985-807281342/HX8379_C_2_5inch_50pin_24bit_tft_lcd_display_module.html

Oh wait, I just found the MIPI ~2.47" 480*480 screen. I guess maybe you use DSI-TE, i.e. it comes as a DSI packet.

I'm going to order a couple of those because I'm interested in the increased resolution, although the lower brightness is a downer.
luiHS:

These are my round screens, I have some smaller 1.2 and 1.39 inches, also MIPI.
I also bought two HDMI controller boards to connect the screens to the computer, for initial tests.



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