Please Help with 8x8 Led with Maxim 7219

Using Arduino LEDs and Multiplexing
1

:astonished:

Where is the Library ledControl.h located?

I just got the 8x8 Dot matrix module with a maxim 7219 and the only code (workable) is one that puts a diagonal line on the display.

Has anyone come up with a simple code that just makes the module count 0-9? ... and if it takes at special library that does not come with the ide, can you post a link to it?

If there is some sketches out there for a single module to do neat light show displays that would be great too.

Please Help... I am trying to get my eight yr old interested in programming so help me dazzle this thing.

2

Can you please provide a link to to the module that you are using ?

3

Download LedControl library here

How to install libraries

I can direct you to this code YouTube video I did if you are interested. Let me know 8)

4

Thanks Pedro147... that simple comment opened up a lot.

5

I found a repository at:

https://arduinocode.codeplex.com/releases

and when I try to compile a sketches using the "MD_MAX72xx.h" library, I get this error message.
Any clues???

In file included from /usr/share/arduino/libraries/MD_MAX72xx/MD_MAX72xx_font.cpp:25:0:
/usr/share/arduino/libraries/MD_MAX72xx/MD_MAX72xx_font.cpp:132:24: error: variable ‘_sysfont_var’ must be const in order to be put into read-only section by means of ‘attribute((progmem))’
uint8_t _sysfont_var[] PROGMEM =
^

6

am pretty sure that this is the code in that video

7

In file included from /usr/share/arduino/libraries/MD_MAX72xx/MD_MAX72xx_font.cpp:25:0:
/usr/share/arduino/libraries/MD_MAX72xx/MD_MAX72xx_font.cpp:132:24: error: variable '_sysfont_var' must be const in order to be put into read-only section by means of 'attribute((progmem))'
uint8_t _sysfont_var[] PROGMEM =

What version of the IDE are you using and on which OS?
Please confirm that the libraries are the downloaded from the site as a zip file recently? Better still, what version is in the zip file name?

8

Hey Macro_C,

I am using OS Linux Mint 17... Windows has too much bloat-ware on it.

Hey Pedro147:

I don't think it's the same one, but it is very cool...

I use the pinouts via the Funduino Multi-Function Shield (pins 5,9,6 for Din, Clk, Cs) so i can have handy switches, pot, 7 seg display, beeper, etc... if I want to add controls to sketches.

That light show is a very good 'upload-n-go' sketch.

Thanks...

9

TheScientist:
Hey Pedro147:

I don't think it's the same one, but it is very cool...

Yeah, I wasn't sure. I will connect up the circuit over the weekend and try and find it for you.

Edit - John I am sure that this code is very close (hard to tell as my brain is not that fast :smiley: )

This shows how to control individual LED's and rows / columns as well

10

TheScientist:
I am using OS Linux Mint 17... Windows has too much bloat-ware on it.

Now you're talking!