kbeckmann/PicoDVI-N64

Full N64 color space and resolution with the just announced Pico 2?

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I wonder how much work it would be to port this over to the new Pico 2. https://www.raspberrypi.com/products/rp2350/

The Pico 2 has built-in 520 KiB RAM. This is nearly double what the first Pico came with.

Currently PicoDVI-N64 works with a 320x240 internal framebuffer with up to rgb565 color depth.

The N64 can output up to 640x480 with rgb777.

Is it feasible to actually handle 7 bits per color? This would mean that each pixel consumes 21 bits which does not fit into the 8 bits raster. Assume this is possible and we only want to support 240p content. This would result in 395 KiB memory usage and so could fit into the Pico 2 RAM.

And then I found this one: https://shop.pimoroni.com/products/pimoroni-pico-plus-2
The new RP2350 seems to have external RAM support and this variant comes with 8MB of additional RAM. So the full sized frame buffer should fit with ease.

So long story short: I don't know if it would be possible at all but if this project can be extended to full color space and resolution, this would be a really interesting low cost HDMI mod. Currently (in my opinion) it is a nice demo to show what is possible with the RP2040 but the native resolution of the N64 already is not that great on big HDMI screens. Further limiting this doesn't really improve things.

https://m.youtube.com/watch?v=kQzxHdXNY6g
Maybe Adafruit will also provide software for this.