Pi/GPIO

pin 4 supports a CLOCK mode, which can be used to drive various digital ICS. To enable this mode install the modified GPIO libraries from the pi project;

http://www.cl.cam.ac.uk/projects/raspberrypi/tutorials/robot/cheat_sheet/

there are some further docs on the GPIO and the GOIO utility to control the pins from the command line;

http://wiringpi.com/the-gpio-utility/ gpio write 0/1 This sets an output pin to high (1) or low (0)

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