Yes, I can get them all to show at same time. I’ve now got the setup to show 11111111 on all units, then 22222222, then 33333333, etc up to 999999999. Started to write the software to show exactly what I want. I’ve got the two 3x5 keypads working with it all as well using interrupts.
All in all it’s going well now that I’ve got the display working.
Thanks for your continued help.
The library referred to in this thread is well out of date.
The author of the library Andrew Davis of Hobby Components advises not using the github library, but to download the latest version from the Hobby Components website.
The latest version appears to be version 0.5.
I couldn't get the code examples in this thread to compile.
It doesn't like things like MAX7219.clear() or HCMAX7219 MAX7219(LOAD);
The HCMAX7219 examples all use HCMAX7219 HCMAX7219(LOAD); or HCMAX7219.clear();
Even the old version 0.2 examples use /* Create an instance of the library */
HCMAX7219 HCMAX7219(LOAD);
Just a thought.
I know its an old thread, but I have seen this problem referred to elswhere, where only the first 5 or so modules light.
In case ths comes up in a search ...
If you are daisy-chaining them out to in, there is a polarity protection diode on the +5 input, which loses over half a volt each board, so short out each of the diodes ( and ake sure not to connect the supply reversed )