Arduino,Matrix,Max7219

Hello to all,
I would have to solve a problem that I really can not understand ;
My intent is to appear on my led matrix lettering .
I then connected to the arduino max7219 max7219 e and the matrix .

This is the datasheet of the matrix in my possession :
https://www.sparkfun.com/datasheets/Components/LED/YSM-1288C

The connections are made ??by me seguenti_
22 - pin matrix DIG0 of max7219

  • " " 19 " " DIG1 " "
  • " " 16 " " DIG2 " "
  • " " 13 " " DIG3 " "
  • " " 3 " " DIG4 " "
  • " " 6 " " DIG5 " "
  • " " 9 " " DIG6 " "
  • " " 12 " " DIG7 " "
  • " " 23 " " SEGDP " "
  • “” 20 " " SEGA " "
  • " " 17 " " SEGB " "
  • " " 14 " " GCSE " "
  • “” 2 " " SEGD " "
  • " " 5 " " Sege " "
  • " " 5 " " SEGF " "
  • " " 11 " " ET SEQ " "

If you look at the datasheet for the max7219 and read at this link:
http://playground.arduino.cc//Main/LEDMatrix # . UxOHeuN5OVM
Note that it is necessary to insert a resistor and two condensatori.La resistance I inserted 27KW , while the capacitors same as it is written .
Then I loaded it on the following Arduino sketch (Copied from the internet now to make sure it’s working)

include " LedControl.h "
LedControl LedControl lc = ( 12,11,10,1 ) / /

/ / Pin 12 is connected to the MAX7219 pin 1
/ / Pin 11 is connected to the CLK pin 13
/ / Pin 10 is connected to LOAD pin 12
/ / 1 as we are only using 1 MAX7219

void setup ()
{
/ / The zero Refers to the MAX7219 number, it is zero for 1 chip
lc.shutdown (0 , false) ;/ / turn off power saving , Enables display
lc.setIntensity (0.8) ;/ / sets brightness (0 ~ 15 possible values)
lc.clearDisplay (0) ;/ / clear screen
}
void loop ()
{
for (int row = 0 ; row <8 , row + +)
{
for (int col = 0 ; col < 8 , with + +)
{
lc.setLed ( 0, col , row , true) / / turns on LED at col, row
delay ( 25);
}
}

for (int row = 0 ; row <8 , row + +)
{
for (int col = 0 ; col < 8 , with + +)
{
lc.setLed ( 0, col , row , false) / / turns off LED at col, row
delay ( 25);
}
}
}
then I connected the arduino to 1 of 12 max7219 , the 11-13 , and 10-12 .
After powering up the circuit I also tried to turn even arduino , but the matrix does not appear absolutely nothing.
I have no idea what it might be and I have no idea what to do … the matrix works because I tested , the max7219 is new, but never say never … but do not know how to test it … have any suggestions on what to do ? … or possibly tell me what I did wrong ?
Thank you very much . :slight_smile:

lc.setIntensity (0.8) ;

Is 8) a new C keyword I'm not familiar with?

Use CODE tags, edit the post, select the code, click on the # button. Then fix all the indenting (^T in the IDE)


Rob

Graynomad: lc.setIntensity (0.8) ;

Is 8) a new C keyword I'm not familiar with?

Use CODE tags, edit the post, select the code, click on the # button. Then fix all the indenting (^T in the IDE)


Rob

I thought I'd connect Arduino directly to the matrix, using two potentiometers .. how can I make the connections and the program?

Andrea_21: have any suggestions on what to do ? .. or possibly tell me what I did wrong ?

If you go back and look at what you first posted here, you will see that your code has not shown up correctly - that is what Graynomad was pointing out to you.

You need to do things methodically, step by step. That applies equally to posting here, as it does to getting your circuit to work. Most of us would rather not have to figure out code that is not properly presented, as well as figuring out why it might or might not be correct, so do please go back and select "modify" on your first posting above, highlight the actual code section and tag it as code using the "code" button [ # ] above the submit window. Then we can have a look at it.

Once you have done that, we need to try and figure out whether it is your code, your wiring, or both that is the problem. Given that we have your code in a readable form, we also need to see how you have wired it. We need a clear, focused photograph or two of your assembly, appended to a post here using the "Additional Options" function, preferably sized 1024 by 768 or slightly smaller.

Andrea_21: I thought I'd connect Arduino directly to the matrix, using two potentiometers .. how can I make the connections and the program?

I realise you are not a native English speaker, but "using two potentiometers" makes no sense; what did you actually mean? To drive the matrix, you need the MAX7219; you need to wire it correctly and program the Arduino. Going off on a tangent will only get you all the more confused.