LED dot matrix scrolling message w/ soure code

Discussion in 'The Projects Forum' started by takao21203, Feb 23, 2014.

  1. takao21203

    Thread Starter Distinguished Member

    Apr 28, 2012
    Hope it is useful and interesting, I show the complete source code. Making the scroll working only takes minor modifications.


    There is no schematic required, since I have, during years of work, designed a method to describe the components and the IO layout with tables.

    It is pretty much almost hardware independent. You can use conditional define for different controllers!

    The LED matrix size can be changed easily.

    One thing is, somehow I have one common anode and one common cathode mixed! The components have the same number- it's a bug!

    So I use a different table for the second module (there are two).

    You could also use digital MOSFETs for the anodes (PNP), and then you can remove a few IO lines. But it works without any extra components, at 5 volts.

    8MHz oscillator. It;s easy to change from PIC16f884 to any microconntroller. The hardware port names are put into a table- simply change to the names used by your controller: Arduino, Raspberry PI, STM8, etc.

    There is no schematic, since I can coonnect LED matrix module to any random pins. The scheme is written into a table. Instead of dealing with a schematic, I deal with a software table.

    I use about 1/3 of the 4K FLASH, and 1/2 of the 256 bytes RAM.

    There are no external components at all (the buttons not yet connected). It is powered from the PICKIT3 at 5 volts.

    If you want to try the source, you will have some work to copy/paste, and i'd ask to retain the copyright notice. Zipped file on request. I will update the page soon with a video, and updated code to animate the scroll, and maybe to edit message with the buttons.
  2. THE_RB

    AAC Fanatic!

    Feb 11, 2008
    It's nice to see someone making things and posting them up for others. Good work. :)
  3. Ian Rogers


    Dec 12, 2012
    Yeah! I agree with Roman.... I like your coding style....Others should use this as an example of how to lay out your code!!!