Moving forward one more step towards some mysterious 7-segment display goal I have in mind, tonight I was testing the clock display I had.
For those paying veeeeerrry careful attention, this clock display might look familiar - I used it in a project 11 years ago 
The interesting thing to keep in mind for these displays is that you don't need to make it very complicated in order to see some results - they are really just LEDs lined up in a neat little display package.
That's also why it's a good idea to add the current limiting resistors.
The way this clock display is set up, as I suspect most are, there are 7 wires for the segments, shared for all of the digits, and then a separate wire for each digit.
So for this first step, I found it easy to just use a little 3v button cell battery to test how things fit together - and as you can see in the pictures, by connecting the 7 wires corresponding to the segments and then touching one of the four wires corresponding to each digit to vcc, you can light them up for testing.
My clock display is LTC-617D1G. I think the data sheets will still be online for that too, but I'll add a description once I get things running more.
Next step will be to light up the digits with the Pi Pico - notice that, because we only have the shared 7 segment wires, we will have to set up each digit individually, then light it, then set up the next digit, etc and repeatedly run through them to display a given time.
-Nico
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