USB and Serial Communication - Exploring Arduino: Tools and Techniques for Engineering Wizardry - page 125

Sending Lists of Values to Control an RGB LED
Sending a single command character is fine for controlling a single digital pin,
but what if you want to accomplish some more complex control schemes? This
section explores sending multiple comma-separate values to simultaneously
command multiple devices. To facilitate testing this, wire up a common cathode
RGB LED as shown in Figure 6-11.
Figure 6-11: RGB LED connected to Arduino