It is easy to hook up knobs, LEDs, and switches to the Critter Board. The example code shows how to handle the software side of things. To run the example unpack the archive, and run 'make' and then upload the main.hex file to the Critter Board.
The Critter Board has one row of 16 connections, and one row of 5 connections. The pinouts are listed in the hardware reference. By default, these pins are general purpose digital input/output lines. The can be used to read switches and light LEDs. 11 of them are also connected to the LPC2138s analog to digital converters. Check out the LPC2138 datasheet for information.
The example code uses 2 LEDs, one switch, and one potentiometer. When the switch is held down, one LED turns on and the other LED flashes at a rate specified by the pot. The two LEDs are connected to P0.23 and P0.20, the switch is connected to P0.13, and the potentiometer is connected to P0.15 (ADC1.5).
Here are some hook up diagrams.
Diagram for hooking up a pot:
Diagram for hooking up a LED:
Diagram for hooking up a switch:
