A new Heart in an Old Box
The new pulsing heart of the old smart clock will be the .for two reasons: the first is the interior design of the box that seems created to host the micro:bit and the second is the power of the micro:bit and the incredible availability of options on this small board. There is a third reason too, I am fan of the micro:bit
With a couple of screws I fixed a to the bottom of the clock box, replacing the original motherboard. As the micro:bit should remain closed inside the clock the on-board LED matrix display will not used. One of the goals of this rebuild (or smartification?) is to leave untouched the original design and style of the device.
Just for luck, the original 220V power cable made easy to fix the USB programming and power supply cable. To keep the board in place I had to modify the attachment of the 8 Ohm speaker removing the fixing screws and hot gluing the speaker after cutting the screw support.
The top cover of the clock will not be screwed but only closed with an internal spring as the micro:bit should be programmed so I decided to use the clock alarm on-off switch to add the battery pack as shown in the image below.
The 7=segments Display
The 7=segments LED display I have used as replacement of the original clock is a bit smaller so it was possible adding a couple of LEDs for the AM/PM 12 hours display format.It is a 4-digits single component for which I plan to use a 7=segment display IC controller. The datasheet of the component is available in attach.
The Real Time Clock
For the real-time clock I have used a breakout board including the backup battery and the clock based on the IC (datasheet in attach) This hardware is easy to control by the micro:bit but I expect to be challenging the software control.
The next part will be testing separately the components before completing the software programming