> The "Status" LED flashes some kind of code - long long, short short short. I assumed the number of flashes would correspond to the time but apparently not. We didn't have time to figure this out before we had to leave.
long-long-short-short-short is 7 in morse code. They don't say what time they tried this or if it ever changed, though, so that's just a hypothesis.
It's almost certainly this. I suspect the advance button can be used to advance the time via morse code LED flashes and only then committed when you get to the right hour.
Perhaps the long-press commits the hour, which is why it rang once initially.
As an engineer i would never think that complicated - morse code?
Couldn't it be just binary
long-long-short-short-short
11000
Which is - to everyones surprise - 24 as in hours.
To anyone other than a computer engineer, I would bet Morse code would be preferred at least 10 to 1. Most people who aren’t computer science majors could barely decode binary “10” correctly, whereas writing down the dots and dashes and googling “Morse code chart” is something I’d bet over 50% of non-engineers could do accurately.
How is this any different than decoding binary? If you can read a chart of codes involving either dot or dash surely you can also read a chart of codes with either 0 or 1.
I used to use Morse to blink out status codes in similar things but I think by the mid-2000s I'd moved from PIC16F628s to atmega328.
I didn't build the chime box but it looks like the sort of thing I used to do back then.