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8x8 matrix with a MAX7219 with arduino Mega

Is there some type of code (even if incomplete) that I can take a look at to control this matrix.

thanks for any help in advance

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My objective is to be able to write (turn on) 1 or more indicators (on the matrix) dynamically.

is this done using SPI in my scenario. I know there are Vcc, GND, Din, Cs, and SCK

clk and cs I have them connected to DIO 52 & 53, Din I have it connected to DIO 12

but iam struggling into conceiving the spi part.

again any help will be appreaciated.

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I changed to the arduino UNO.

DIN --> pin 10

CS --> pin 11

CLK-->pin 13

8x8 matrix.PNG

here is the code I have

Code.PNG

Iam writing 1 byte at the time (every event). all it does is make the LED brighter.

say I wanted to make letter A light on the matrix.

Again any help will be appreaciated.

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Iam thinking about having a 2D array boolians that I can set up dynamically and converting that into something that I can write to the ship and hence turn on the appropiates output.

Code1.PNG

I just cant make the matrix plash the way I want to.

Iam I going through the right path here?

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no one can give me a hand here?

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If you could post a link to where you purchased it and possibly example Arduino (or other) example code, it would help.  I didn't study the datasheet extensively but I could only find reference to 7 segment LEDs which only had options to display numbers and specific letters for a 7 segment LED which won't work for the LED array.

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thanks for the replay.

I dont have a link for the little matrix board. (it looks exactly like the one on the picture. (has I/Os including reference and vcc.

I did look at a couple of tutorials done in C and both showed a video at the end writing letters and numbers on the matrix.

one of them is : http://tronixstuff.com/2010/07/09/review-maxim-max7219-led-display-driver-ic/

Iam sure I have the right pins for the connection CS, SCK, and DIN as well as VCC and GND.

Iam also sure the problem lies on the software (specifically on the SPI VIs )

iam missing something hopefully trivial here.

here i send you a piece of code to see if it makes sence to you.Capture.PNG

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Nathan,

here are some of the stuff you requested earlier.

http://playground.arduino.cc/LEDMatrix/Max7219 this is a sample code for a matrix control.

here is another example: http://playground.arduino.cc/Main/LedControl here is exactly what i want (on the matrix control)

they call the row, colum of the given led(s) to display and then they write the binary value example:

Capture2.PNG

I cant seem to achieve this on my scenario.

http://playground.arduino.cc//Main/LedControlDemos here is anothee example

Capture.PNG

iam here trying to just write 1 byte representing the top row on my 2d array just to see something.

output spi data is always = 53.

Capture1.PNG

the actual array iam not using it rather the numeric control to simulate a 1d array = to row0

the videos and such show the LED matrix 8x8 just like mine indicating letters, numbers and paterns.

Again any help will be appreciated.

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No one? 😕

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Hi!

Some days ago I get two of this Matrix, and at the beggining I also think that the MAX7219 (due that this product mix a 8*8 matrix and the MAX7219) worked in the same way that have 2 74HC595, I mean: 8 bits for control columns, and 8 bits for the control of the rows. But that it's not right, the MAX7219 work with 16 bits, but like Nathan says, this is a driver for control 7 segments displays, not a LED matrix, and also has some other features that depend of the Data that you send to it. You can't send 8 bits for the columns and 8 bits for the rows, because the distribution of the data for the MAX is the next:Data.png

Taking this table and other stuffs from the Datsheet I made a LabVIEW code that already work and in which I show how the driver works: https://decibel.ni.com/content/docs/DOC-36277

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