Adding LED fading to word clock

Just to add it's not quite Charlieplexing - just standard multiplexing.

As @allObjects says analogWrite is unlikely to work, but you can slow down the update rate, which will in turn dim the whole image.

startScanning actually returns the 'interval number', so if you change the line startScanning(); to scanInterval = startScanning(); then you can then use changeInterval(scanInterval, X); to change the brightness.

Having X as 10 is the default (100Hz), but you could slowly change it to 100 (which will start to look a bit flickery, but which will be 1/10th of the brightness).