As this PIC has six pins and is the size of an SMD transistor, it is ideal for low profile applications and can easily be reprogrammed as and when needed.
In this case I am using the "reverse polarised LED" trick to get six LED's working from three I/O lines, as detailed in Microchip's "Application Notes".
Runs on two 3V cells, as the PIC's maximum voltage is around 7V this is acceptable and the cells last a lot longer this way.
can be used with any of the 10F20x series but you may need to modify the code slightly.
Have fun, -Andre
Step 1: Program the PIC(s)
Note that this PIC requires ICSP, which means if your programmer doesen't support this then you will need to find one that does. External 5V is needed, here it is provided from a 9V battery and 7805 regulator.