MiSTer FPGA Forum

I recently got a screen from Adafruit that wanted to connect to my mister for a project but I'm having trouble setting the correct video mode.
The screen works when connected to a PC or laptop and was able to get some info from the EDID and datasheet to figure out the timings, but for some reason is not working.

I noticed the EDID says the screen is 7'' where as mine is 5'', but not sure if that's relevant at all.
Another interesting thing is that if I connect the HDMI through my video capture device then it works. No idea why, my guess is that the capture device is doing some processing that "fixes" the signal somewhow.
Saw in another similar post that tweaking the back porch under 10 gives some "stable" image, and I observed the same on mine, but is still not correct.

See details below, any ideas? anyone?


Anyhow, alledgedly the correct video mode should be the following:
video_mode=800,40,48,40,480,13,3,29,32000

Based on:

The screen datasheet: https://cdn-shop.adafruit.com/datasheet ... 0NT-A1.pdf

PC Radeon Settings: And the reported EDID:
Monitor
Manufacturer............. ADA
Plug and Play ID......... ADA0004
Serial number............ 1
Manufacture date......... 2007, ISO week 1
Filter driver............ None
-------------------------
EDID revision............ 1.3
Input signal type........ Digital
Color bit depth.......... Undefined
Display type............. RGB color
Screen size.............. 150 x 100 mm (7.1 in)
Power management......... Not supported
Extension blocs.......... None
-------------------------
DDC/CI................... Not supported

Color characteristics
Default color space...... Non-sRGB
Display gamma............ 1.00
Red chromaticity......... Rx 0.000 - Ry 0.000
Green chromaticity....... Gx 0.000 - Gy 0.000
Blue chromaticity........ Bx 0.000 - By 0.000
White point (default).... Wx 0.000 - Wy 0.000
Additional descriptors... None

Timing characteristics
Range limits............. Not available
GTF standard............. Not supported
Additional descriptors... None
Preferred timing......... Yes
Native/preferred timing.. 800x480p at 66Hz
Modeline............... "800x480" 32.000 800 840 888 928 480 493 496 525 -hsync -vsync

Standard timings supported

Report information
Date generated........... 11/07/2021
Software revision........ 2.91.0.1043
Data source.............. Real-time 0x0061
Operating system......... 10.0.19043.2

Raw data
00,FF,FF,FF,FF,FF,FF,00,04,81,04,00,01,00,00,00,01,11,01,03,80,0F,0A,00,0A,00,00,00,00,00,00,00,
00,00,00,00,00,00,01,01,01,01,01,01,01,01,01,01,01,01,01,01,01,01,80,0C,20,80,30,E0,2D,10,28,30,
D3,00,6C,44,00,00,00,18,00,00,00,10,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,10,00,00,
00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,10,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,17

I had more time to experiment with and got some results that might help somebody to figure out what's going on.

This is the image in the screen when passing the signal through the video capture device.
video_mode=800,40,48,40,480,13,3,29,32000 ; video mode based on datasheet
Image when HDMI is plugged directly.
This is the image tweaking the modes, reducing the front and back porch values from 40 to 4.
The colors in the background are ok, but the menu is not shown, and although it can't be seen in the picture, the top and bottom vertical lines flicker.
video_mode=800,4,48,4,480,13,3,29,29517 ; bg colors ok, no menu, unstable top and bottom lines
Also tried to reduce the HSync but the colors are wrong, although some part of the mister logo is now visible.
video_mode=800,4,12,4,480,13,3,29,28276 ; bg colors wrong, cut logo, no menu, no top-bottom flicker
showing
And lastly I made a video of me toggling through the backgrounds (F1), noticed like it seems the active area is wrong, is only showing the first few columns, hence why the logo and menu are not visible.
video_mode=800,4,48,4,480,13,3,29,29517 ; bg colors ok, no menu, unstable top and bottom lines

https://imgur.com/a/aj3IrbM