Rabbit RabbitCore RCM4400W Product Manual - page 27

OEM User’s Manual

19

•

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 Proto-

typing 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 RCM4400W modules interact, you can move on and try the other 

sample programs, or begin building your own.