Specifications

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the power is low to let the user know that the battery is almost discharged and inform
the user that there will be a need to connect to a different power source unit before
complete shutdown. I estimate 10 minutes before would be sufficient enough to let the
user know about the situation. If the user ignores this we will then send out another alert
when there is 5 minutes of battery left and a final alert when 2 minutes of battery is left.
Figure 28 - Backlight Brightness for LCD Screen
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In figure 2 you can see that there are many operations of the LCD screen brightness.
We will be using value 128 to turn off the LCD screen and will operate it at 140 value
which is mapped to 40% brightness. As you can see you can map the whole range with
this LCD screen by mapping the value between 128 and 157 inclusive. The LCD will be
connected in serial as in the figure below you can see the serial connection that it will
make with the MSP430. We are using a low power microcontroller to save power for the
other operations of the power system. This LCD interfaces with the MSP430 which we
have tested with by writing a test program and seeing if the LCD will be able to interface
with the MSP430. In the figure below you can see the serial connection that the
MSP430 will make with the display this we will also incorporate the buttons which will
change the display and turn it on and off. This is a important factor in making our display
multifunctional as well as making it user friendly so that a novice user can use it without
any problems.