Arduino Forum

Using Arduino => LEDs and Multiplexing => Topic started by: TheScientist on Jan 21, 2015, 04:12 pm

Title: Please Help with 8x8 Led with Maxim 7219
Post by: TheScientist on Jan 21, 2015, 04:12 pm
 :smiley-eek:

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.
Title: Re: Please Help with 8x8 Led with Maxim 7219
Post by: UKHeliBob on Jan 21, 2015, 07:49 pm
Can you please provide a link to to the module that you are using ?
Title: Re: Please Help with 8x8 Led with Maxim 7219
Post by: Pedro147 on Jan 22, 2015, 03:34 am
Download LedControl library here (http://playground.arduino.cc/uploads/Main/LedControl.zip)

How to install libraries (http://arduino.cc/en/Guide/Libraries)

I can direct you to this code YouTube video (https://www.youtube.com/watch?v=_0dVsDgVNpw) I did if you are interested. Let me know  8)
Title: Re: Please Help with 8x8 Led with Maxim 7219
Post by: TheScientist on Jan 22, 2015, 01:05 pm
Thanks Pedro147... that simple comment opened up a lot.
Title: Re: Please Help with 8x8 Led with Maxim 7219
Post by: TheScientist on Jan 22, 2015, 01:13 pm
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 =
                        ^
Title: Re: Please Help with 8x8 Led with Maxim 7219
Post by: Pedro147 on Jan 22, 2015, 07:28 pm
 am pretty sure that this is the code (http://www.mediafire.com/view/wjxcc9w8a8xsrdo/Compilation_Of_All_Mk3.ino) in that video
Title: Re: Please Help with 8x8 Led with Maxim 7219
Post by: marco_c on Jan 22, 2015, 07:55 pm
Quote
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?
Title: Re: Please Help with 8x8 Led with Maxim 7219
Post by: TheScientist on Jan 23, 2015, 01:19 pm
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...

Title: Re: Please Help with 8x8 Led with Maxim 7219
Post by: Pedro147 on Jan 23, 2015, 09:43 pm
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 (http://www.mediafire.com/view/hsx8w6d6m64jk16/Compilation_Of_All_Mk1.ino) is very close (hard to tell as my brain is not that fast :D )

This  (http://playground.arduino.cc/Main/LedControl)shows how to control individual LED's and rows / columns as well
Title: Re: Please Help with 8x8 Led with Maxim 7219
Post by: Paul__B on Jan 24, 2015, 07:46 am
I am using OS Linux Mint 17... Windows has too much bloat-ware on it.
Now you're talking! (http://www.christianmums.com/forum/public/style_emoticons/default/thumbs-up-smiley%5B1%5D.gif)