GPU Tutorial Questions


I’m reading through the tutorial at:

I have a few questions:

  1. Is there a wiring diagram available for the LCD? Assuming the video on the tutorial page is accurate, I can see the pins on the D0 side of the LCD board that are used, but I don’t see a way to trace the wires in the picture/video from the LCD to the Alchitry. Looking through lcd.acf, I’m not seeing any reference to D0 or any way to use this acf file as a wiring diagram.
  2. Is this tutorial fully functional? I see shader.luc in the source directory, but in the URL I listed above, it says the shader is “coming soon”. Does that mean a working shader is coming soon, or that an explanation of how the shader works in coming soon?

Any help appreciated. Really excited to start using the Alchitry Au, and post pictures of a successful project.


  1. There isn’t a wiring diagram but the lcd.acf file should be enough. You can technically use any pins you want as long as you change the acf file to reflect this.

The contents of lcd.acf look like

pin lcd_data[0] A5;
pin lcd_data[1] A6;
pin lcd_data[2] A46;
pin lcd_data[3] A45;
pin lcd_data[4] A2;
pin lcd_data[5] A3;
pin lcd_data[6] A49;
pin lcd_data[7] A48;

pin lcd_wr A9;
pin lcd_rd A42;
pin lcd_cd A43;
pin lcd_cs A8;

DO is lcd_data[0] and is connected to pin A5 on the Br. That is, bank A pin 5. These are labeled on the Br.

D1-D7 are lcd_data[1] through lcd_data[7] respectively.

lcd_wr, lcd_rd, lcd_cd, and lcd_cs correspond to WR, RD, C/D, and CS.

  1. The project is fully functional, I just never finished the explanation. I’m planning to port it to Lucid V2 and the Hd (hdmi) element when it comes out.

You should be able to wire it up, load the project, and have a spinning monkey head.

Let me know if you have any other questions!