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Chinese 'HUB75' RGB LED Driver

q3k's project to create a Zynq-based RGB LED Matrix driver.

Video of a 128x128 panel it action at 32c3.

Overview

This project targets the MYiR ZTurn board with a custom buffer interface board (to be released). The programmable logic exposes a 65-kbyte block RAM to Linux running on the PS via a full-speed AXI slave. The logic also loads data from the BRAM, gamma corrects it and outputs it to the RGB panel interface.

Current Status

It works! But really needs to be re-written. Keep poking q3k on IRC until he does so.

Issues:

  • Vertical glitches Fixed by switching buffers to 5V
  • Low framerate Fixed by switching buffers to 5V and increasing pixel clock
  • Horizontal ghosting
  • No double buffering in hardware
  • No vsync / interrupts
  • No runtime configuration
  • Kernel framebuffer access from userspace (FBDev/DirectFB) locks up whole system
  • Gamma correction is poor, needs and actual ICC color profile correction
  • Hardcoded parameters in kernel/mpv driver

Note: photo of display was taken before dank memes started becoming appropriated by hate groups.

Components

projects/q3kled.txt · Last modified: 2018/04/11 21:16 by q3k