128×32 DMD Update

The verilog code is almost fully debugged. The demo code that will run on a Parallax Propeller is in the works. Right now the demo is fairly basic. Today I wrote a C program that takes a 4-bit bitmap image and strips out the header and and converts it to a 2-bit image. It then reorientates the data so the image is “correct”. Bitmap images data reads the image from bottom left to top right. This is essentially backwards. So the program corrects this which means less work for the microcontroller and faster transmission of pixels.

5 thoughts on “128×32 DMD Update”

  1. Hi there!

    Why limit yourself to only 2-bit color? I’ve managed to get 16 colors using a Chipkit and a little preprocessing to separate the different layers and still achieve around 100 Hz performance. The SD card reading is a bit on the slow side so while streaming video I’m limited to 8 colors at 14 FPS (but still around 100Hz).

    Or is it a strategical decision to only have B&W? :)

  2. My bad, you wrote 2bit so that would mean 4 possible values. But the question remains.

    I wrote my image conversion using Python. Very simple, but efficient. Animated GIF’s are supported so converting an animation to a single binary DMD file is possible. As I don’t know the official DMD format it’s simple a lot of bytes cramed together and in its current state quite crude. Let me know if your interested in seeing the code. :)

    1. I actually have a C program that takes bitmaps and rips them apart. I haven’t posted it yet but I will when I get the FPGA code hammered out.

      1. Awesome!
        Hope to see some cool Reset Vector related progress soon!

        I changed my theme btw, last time we spoke it was based around the Fallout universe… but it’s now Bioshock instead. Same same, but different. ;)


Leave a Reply to Robert Cancel reply

Your email address will not be published.