 For instance, a display in Texas uses a PIC microcontroller-based dimmer scheme, and also refers to dimming controllers that people have built based on this scheme.The designs all use mid-range PIC microcontrollers, are generally modular in units of eight channels (dimmable circuits), and use medium-speed, daisy-chainable, one-direction serial communications for input.Most controllers do not have stand-alone show sequencing capabilities, and rely on a separate computer (usually a PC) to send it real-time sequences of dimmer commands.