I'm often asked by friends who tinker with the Arduino family, "Can my code run on the Propeller?"
I have ported lots of Arduino code to Spin, and as a project for a book I'm working on, decided to port the LedControl library (for MAX7219s) this afternoon. I already have a low-level library for the MAX7219 (jm_max7219.spin), but LedControl supports chained devices and I really wanted to do this as an exercise.
It turned out to go pretty smoothly. I started with a near line-for-line translation of Arduino C to Spin. In a few areas I used things like bytemove() and bytefill() for efficiency, along with left-shift for power-of-2 multiplication (which the original author chose not to do). Once done and tested I made a couple small modifications and additions because I think the library needs them.
So... if you're looking for a multi-device MAX7219 library, I hope you'll give this a try and let me know if you find any problems.
It's Jon or JonnyMac -- please do not call me Jonny.