I had put off getting going with the RTC after reading about 'issues' others had had with the board I got. Eventually I just got on with it and was easier than expected.
Setting the time was hampered slightly by the realisation that the time is set at compile time and then transferred. There's probably a clever way to set it over serial, but I went for timing the compile and upload and compensating for that (19secs) It's accurate to within one second which will do for me.
Tidied up the clock code to try using one LED on the inner ring and two on the outer for the hour, so you get a triangle for the hour. For the minutes I've filled the outer ring proportionally. Looks ok but currently is only good for 2.5 mins accuracy.
I'm going to try fading up the next pixel which should allow a guess at the time within 30 secs to the trained eye. May try some other options
Maybe also add markers for 12,3,6,9
I will add a second blinker, I think a radial sweep looks really cool but may get a bit distracting in normal use.
Still to do is something interesting with the colours, alarm function, switch and a case.