Need help chaining 8x8 led modules.

Searching the web I have found a number of tutorials on how to chain a single row of 8x8 led matrix modules but for the life of me, I can’t find anything on how to chain 2 rows of 8x8 led module to form a 64x16 display. I’m not sure if you would chain all of the modules in the first row and then chain the last module in the first row to the first module in the second row or what? Can anyone steer me to such a tutorial or just explain to me how this is done? It would be very much appreciated.

Thanks

Check the parola.h library, uses a MAX7219 per 8x8 matrix for display, allows chaining I think in multiple ways. https://parola.codeplex.com/

What modules do you have? How are you powering them? What library are you using?

If you are using ledcontrol, you need to create a new instance for every 8 matrices

CrossRoads: Check the parola.h library, uses a MAX7219 per 8x8 matrix for display, allows chaining I think in multiple ways. https://parola.codeplex.com/

Thank you very much, I'll check that out.

INTP: What modules do you have? How are you powering them? What library are you using?

If you are using ledcontrol, you need to create a new instance for every 8 matrices

I have 8x8 led matrices mounted on a small PCB with Max7219s. I bought about 20 of them on eBay. I'll be using them with the Arduino.

The 8x8 modules with Max7219 only chain as one long chain (ie, a linear array). If you want to double them up then you have 3 choices:

  1. Have 2 linear arrays one on top of the other. This doubles the connections to the Arduino. It also can complicated software. Not recommended.

  2. Run the array so that it doubles back on itself. With 12 modules you would have them numbered like this, folded over at the connection between 5 and 6:

00 01 02 03 04 05
11 10 09 08 07 06
  1. Similar to 2 but reset to the start of the line again. I think this is what you suggested in your question. The connection is still between modules 5 and 6.
00 01 02 03 04 05
06 07 08 09 10 11

Either 2 or 3 are the better scheme, with 2 minimising the length of wires used.

If you use the Parola library to display double height text, the way the modules are arranged is a variation on item 2 above.

06 07 08 09 10 11
05 04 03 02 01 00

Thank you very much for the choices. I'll give that a try and see how it works out. Very much appreciated.