User’s Manual
18
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TAMPERDETECTION.C
—demonstrates how to detect an attempt to enter the bootstrap mode.
When an attempt is detected, the battery-backed onchip-encryption RAM on the Rabbit 4000
is erased. This battery-backed onchip-encryption RAM can be useful to store data such as an
AES encryption key from a remote location.
This sample program shows how to load and read the battery-backed onchip-encryption RAM
and how to enable a visual indicator.
Once this sample is compiled and running (you pressed the
F9
key while the sample program
is open), remove the programming cable and press the reset button on the Prototyping Board to
reset the module. LEDs DS2 and DS3 will be flashing on and off.
Now press switch S2 to load the battery-backed RAM with the encryption key. The LEDs are
now on continuously. Notice that the LEDs will stay on even when you press the reset button
on the Prototyping Board.
Reconnect the programming cable briefly and unplug it again to simulate an attempt to access
the onchip-encryption RAM. The LEDs will be flashing because the battery-backed onchip-
encryption RAM has been erased. Notice that the LEDs will continue flashing even when you
press the reset button on the Prototyping Board.
You may press switch S2 again and repeat the last steps to watch the LEDs.
•
TOGGLESWITCH.C
—demonstrates the use of costatements to detect switch presses using the
press-and-release method of debouncing. LEDs DS2 and DS3 on the Prototyping Board are
turned on and off when you press switches S2 and S3. S2 and S3 are controlled by PB4 and
PB5 respectively.
Once you have loaded and executed these five programs and have an understanding of how
Dynamic C and the RCM4510W modules interact, you can move on and try the other sample pro-
grams.