Search found 14 matches

by kmatch98
Wed Nov 02, 2022 11:14 am
Forum: Hardware
Topic: ESP32-S3 RGB LCD maximum throughput
Replies: 34
Views: 30600

Re: ESP32-S3 RGB LCD maximum throughput

Yes, this fork of CircuitPython does work with ESP32-S3 and dot clock displays.

See details for the “HACKtablet”.

https://hackaday.io/project/185831-hack ... wn-rebuild

https://github.com/adafruit/circuitpython/issues/6049
by kmatch98
Sat Jun 25, 2022 9:12 pm
Forum: Hardware
Topic: ESP32-S3 RGB LCD maximum throughput
Replies: 34
Views: 30600

Re: ESP32-S3 RGB LCD maximum throughput

I pushed my modifications to the ESP-IDF for the RGB LCD peripheral here: https://github.com/kmatch98/esp-idf/tree/release/v4.4_rgblcd This uses the "bounce-buffer" code to tie up the processor so there aren't DMA memory collisions that starve the LCD peripheral. Also, my code adds the ability to tr...
by kmatch98
Sat Jun 11, 2022 8:16 am
Forum: ESP-IDF
Topic: ESP32-S3 RGB LCD peripheral: weird glitches
Replies: 2
Views: 2277

Re: ESP32-S3 RGB LCD peripheral: weird glitches

Arno, I had the same issue with glitching and tearing. Thanks to some code from the Espressif, I found a working solution: https://www.esp32.com/viewtopic.php?f=12&t=26793&start=20#p95677 This method creates a “bounce buffer” that ties up the processor during the display refresh. This prevents simul...
by kmatch98
Mon Apr 18, 2022 3:08 am
Forum: Hardware
Topic: ESP32-S3 RGB LCD maximum throughput
Replies: 34
Views: 30600

Re: ESP32-S3 RGB LCD maximum throughput

I have now achieved a “non-streaming” trigger-by-code method. I turned off the VSYNC interrupts and call the lcd_rgb_panel_start_transmission function to trigger each redraw. Using this modified code, in my program I finish updating the FrameBuffer, and then trigger the LCD peripheral to redraw to t...
by kmatch98
Sun Apr 17, 2022 2:51 am
Forum: Hardware
Topic: ESP32-S3 RGB LCD maximum throughput
Replies: 34
Views: 30600

Re: ESP32-S3 RGB LCD maximum throughput

Yes, I'd like to be able to control the refreshes. Why: 1. If my code is updating the framebuffer and then the screen refreshes before it is finished, I will get an image that is only partly updated. I think this is called "tearing". 2. If the LCD update requires the processor to use the bounce_buff...
by kmatch98
Sat Apr 16, 2022 1:51 pm
Forum: Hardware
Topic: ESP32-S3 RGB LCD maximum throughput
Replies: 34
Views: 30600

Re: ESP32-S3 RGB LCD maximum throughput

I actually want to control the display refresh, so I want my CircuitPython code to call for the screen redraws. Now that it’s basically working with your constant refresh mode (I think your code constantly refreshes after each VSYNC interrupt), I want to see if it is possible to turn off the interru...
by kmatch98
Sat Apr 16, 2022 5:42 am
Forum: Hardware
Topic: ESP32-S3 RGB LCD maximum throughput
Replies: 34
Views: 30600

Re: ESP32-S3 RGB LCD maximum throughput

One more positive update! Now that using "restart_transmission" was showing some progress, I decided to add back the interrupts (like the original code). For some reason, the code doesn't hang anymore (not sure why this is different from my earlier trials). Now with a 24 MHz dot clock and a bounce_b...
by kmatch98
Sat Apr 16, 2022 3:58 am
Forum: Hardware
Topic: ESP32-S3 RGB LCD maximum throughput
Replies: 34
Views: 30600

Re: ESP32-S3 RGB LCD maximum throughput

Thanks for the suggestions and for the code. I really appreciate the effort that your team is taking to try and get this to work, this LCD peripheral is a great capability to have. I tried adjusting the size of the bounce_buffer_size_px and saw some odd behavior depending on the size. Sometimes noth...
by kmatch98
Fri Apr 15, 2022 4:00 am
Forum: Hardware
Topic: ESP32-S3 RGB LCD maximum throughput
Replies: 34
Views: 30600

Re: ESP32-S3 RGB LCD maximum throughput

I spent today evaluating the code. Unfortunately the project I am trying to integrate it into is rather complex (CircuitPython) so it's difficult for me to give specific debugging feedback about these issues. Here are my observations: 1. This code appears to use all the CPU cycles, so I turned off t...
by kmatch98
Thu Apr 14, 2022 4:25 am
Forum: Hardware
Topic: ESP32-S3 RGB LCD maximum throughput
Replies: 34
Views: 30600

Re: ESP32-S3 RGB LCD maximum throughput

As I said, problems rise when the application code starts using the PSRAM for other purposes, as this seems to "stretch" the GDMA transactions, making the LCD peripheral loose data. The only way to solve this would be some sort of hardware priority schemes which allow GDMA to complete its job witho...