As the title suggests, the clock is powered via a usb cable. When you disconnect the clock or turn off the computer, it will keep going on its battery but it won´t show the time until you reconnect it or switch you PC on again.
For this project, I made my own PCB´s. I have only made 3 PCB´s yet and all in the last 14 days so I am really proud oft them. Any suggestions about those are very welcome!
A small video (the flickering of the LEDS in due to the camera).
Step 1: What do you need:
- 20 x LEDS: Any color you fancy
- 2 x pushbuttons
- 6 x 100Ohm resistors
- 2 x 1.5K resistors
- 2 x 4.7K resistors
- an Atmega 8
- a DS1307 real time clock IC
- a crystal 32.768K
- a USB connector
- A 3V battery + holder ( I used a CR2032)
- a 13pin male header (L-shaped)
- Soldering Iron and solder