Why VGA and not DVI/HDMI


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robert.rozee
Guru

Joined: 31/12/2012
Location: New Zealand
Posts: 1991
Posted: 12:45pm 22 Jan 2022      

  lew247 said  
  JohnS said  
DVI - needs more RAM? (Plus a developer.)
John


Pico can output 30fps 720P DVI full colour video with only resistors
it can also do 1080P 60fps video in black and white only

That's why I asked the question

Video here skip to 2min 49 seconds if you only want to see the video proof


excellent video, showing that acceptable results can be had without needing to go for SMD. all you need is 8x through-hole resistors and a sacrificial HDMI cable.

BUT, i do believe that the code run on the Pico is doubling-up pixels. that is, each pixel value is sent TWICE, so while each line contains 1280 pixels, the ODD numbered pixels are the same as the EVEN numbered pixels.

similarly, each line is doubled up, ie sent TWICE. this is the only way to fit 1280 x 720 into the available RAM on the Pico. you need enough RAM to hold a copy of the screen, and to get a decent number of colours on screen, you have no choice but to double-up the pixels both horizontally and vertically.


having said this, 640 x 350 isn't a bad resolution for running a game. but not so great for displaying text. i'm not much into computer games myself  


cheers,
rob.