Controlling The Led - FIGnition FUZE Hardware Reference Manual

and there is another function (analogRead()) which selects and reads the specified port
C pin.
FIGnition provides direct access to the AVR's ports using ic@, ic!, i@ and i! which
means that individual pins and groups of pins can be read and written.
Arduino supports a 3.3v output, but on FIGnition this is a 3.6v output. The 3.6v output is
achieved by using a pair of diodes as a voltage regulator. Connecting diodes in a forward-
biased direction has the effect of dropping an input voltage by 0.7 at its output [See Ap-
pendix B]. Thus, two diodes in series will drop an input voltage by 1.4v, low enough to
power FIGnition's memory chips. A 1K resistor is used to provide enough of a loading cur-
rent (3.6mA) for the diodes to switch on.
Arduino and FIGnition header rows are spaced 1.9" (48.26mm) apart. On an arduino each
header section is separated from the one below by 0.06" due to a design error in the first
commercial release of arduino 7 . It means that to connect stripboard circuits to an arduino,
offset header pins are required to provide a 0.1" spacing 8 .
Fig 9.2
FIGnition uses a spacing of 0.1" as originally intended. This means that straight pins are
required to connect to stripboard and to connect to a standard arduino shield, the same
offset header pins used to connect an arduino to stripboard should be used.

9.2.1 Controlling the LED

Like an arduino, FIGnition has a built-in LED that can be controlled directly from the ma-
chine. To turn it on, type:
31 40 ic! <exe>
To turn it off, type:
15 40 ic! <exe>
To toggle the LED type:
7
http://forum.arduino.cc/index.php?PHPSESSID=nbfe5ret3vilupk33eomflbdp3&topic=22737.msg171839#msg
171839
8 https://www.sparkfun.com/products/9374