Specifications

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order to set default values, such as the contrast, cursor position, character data,
etc. Use the application code to send a few test strings or simple integers. If they
display on the unit, basic verification is complete. Next, send several integers
consistent with the display format of BAC. If this is successful, the basic
functionality of the display has been verified.
Next, test control functionality of the backlight. If possible, test control of the
backlight by direct commands from the microcontroller, or by adjusting a timer. If
not possible, look for a pin that controls power to the backlight. Wire this pin to a
power transistor, and the transistor to the power supply. This transistor should be
controlled by the microcontroller. Verify that it is now possible to control the
backlight by flipping that particular pin on the microcontroller high or low
(depending on transistor and microcontroller configuration). If successful, the
backlight should turn on or off as expected. Lastly, measure the current while the
backlight is on. If within the expected, relatively low values, the power
consumption portion has been verified.
5.2.5 Verifying Wireless Communications
The MSP430-RF2500 target boards are pre-loaded with a test set of software to
verify communications are working between two boards. The easiest means of
testing and verifying the wireless target boards is to load the application code
provided by Texas Instruments onto each board, and allow the demo application
to run correctly. In order to do this, software must be downloaded from Texas
Instruments, and an Export-Trade agreement must be signed in order to receive
the software from TI. Once the environment is setup inside Code Composer
Studio, there are two available projects that can be configured for build. One is
called the “Main ED”, which is a simple temperature sensing device that
communicates back to the other project, the “Main AP”. Program each board with
its respective software, plug the “Main AP” board into a Windows computer, and
connect to the COM port on your computer that is associated with the debug
stick. Supply power to the “Main ED” board using the battery breakout board, and
look for data coming into the serial port of the computer. Successful
communications will be established if the lights on both boards finish an initial
round of repeated blinking between the Red and Green onboard LEDs, then
begin only blinking the Red LED. This will indicate that packets are being
transmitted from the ED to the AP, and the AP is sending back its
acknowledgement packets successfully.
5.2.6 Verifying Airflow Detection
The airflow sensor or circuitry must first be interfaced to the microcontroller or
other components in the circuit. It must then be mounted into or on the airflow