Specifications

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is also capable of being used with external devices and could easily be used to control
our LCD user display. With packages between $10-$20 and individual parts as low as
$0.50, the MSP 430 is a very affordable option for our group.
An Arduino microcontroller is another board that we could consider using in our design.
This is an open-source single-board prototyping platform that is designed to be used in
electronics for multidisciplinary projects. This microcontroller is also able to use its input
peripherals as sensors, enabling it to affect its environment by controlling electronics
surrounding it.
Arduino microcontrollers are controlled using their own Arduino programming language.
Since this language is very similar to C++, however, learning how to program the board
using this software would not be a hard task. The board can be powered by an external
battery while having a maximum current draw a of 50mA. Since boards can be found at
under $30, we would have no problem budgeting for a Arduino microcontroller.
Texas Instruments also offers another viable option with its Stellaris family of
microcontrollers. This line of microcontrollers combines high performance with cost
effective pricing. A 32-bit microcontroller from Stellaris runs at roughly the same price
as other 8-bit or 16-bit microcontrollers. Included in the Stellaris family is over 140
different members that are based on the Cortex –M3 technology from ARM.
The Stellaris microcontrollers are also capable of both monitoring and converting power
and energy. For ease of use, Texas Instruments allows the user to program the
microcontroller in C/C++. Power consumption for the Stellaris line of microcontrollers
can run as low as 1.6µA while the microcontroller is in stand-by mode.
With these microcontrollers to choose from, we have decided, at this time, to go with the
MSP430 Microcontroller because of its very low power consumption. This will be written
using the C/C++ programming language. The reason why we have chosen this
programming language is because it is an easy language which is required for computer
and electrical engineers. Thus, we should have no problem with this as every member
of our group has taken C programming, which should make it easy as we can all have
input on this subject.
As of right now the software will only be used to get the data from the microcontroller,
which will monitor the status of the system as well as note any problems with the current
status of the system. It will also be used to calculate the charge remaining on the
system. This will require us to come up with an algorithm that relates voltage and
current draw to determine when the system will be out of stored energy and when it will
shut down. It will also have to calculate the amount of charge that will be entering the
system. This farther complicates our measurement because we will have to take that
into account when predicting the amount of time left on the system.