The LED bar shield shall hold two shift registers 74HC595 and a LED bar with 20 LEDs; 16 LEDs of it will be used. The sketch shall choose randomly one of several patterns and run it five to ten times. Then it selects another one.
The first version of the shield was a disaster - the design was much too small. (And the distance were too small to be soldered by a smoker with old eyes ;-)). So I redesigned it with a larger PCB.
Here are some pictures of the first stage populated with one shift register: