Specifications

The above figure shows the MSP430 architecture. As stated before and as shown in

the figure, the MSP430 has its own clock system, capable of functioning with external

devices. The MSP430 is available with either Flash or Read Only Memory (ROM). As it

is our desire to write our own program and to have the ability to reprogram the chip in

the testing phase, we will be sure to use a microcontroller that utilizes Flash memory.

This will be denoted by an “F” part number immediately following the “MSP430” in the

chips name. Also included on the chip is Random Access Memory (RAM) that can be

used for both programmed code and data.

Utilized by the MSP430 microcontroller is a 16-bit Reduced Instruction Set Computer

(RISC) Central Processing Unit (CPU). Included with this CPU is a 16-bit Arithmetic

Logic Unit (ALU), which is capable of handling arithmetic (addition, subtraction, etc.),

comparison and logical operations (AND, OR, XOR, etc.). With 12 of the 16 registers

being used for general purposes, the ALU allows frequently used values to be stored on

the CPU instead of in the RAM, saving time in terms of computing.

Perhaps one of the more important features of the MSP430 architecture that we will be

able to utilize in our design is its “Watchdog” component. This device is able to monitor

the power consumption of external devices that are utilizing the MSP430

microcontroller. The Watchdog is then able to communicate its results to an LCD output

display. Utilizing the Watchdog in our final design software should drastically increase

our efficiency in monitoring the power that is being supplied by out batteries to our

laptop and projector.

These features of the MSP430, as well as the input/output peripherals and ports, and

are all connected by a 16-bit Memory Address Bus (MAB) and 16-bit Memory Data Bus

(MDB). All of these features combined together allow the MSP430 to execute code at

much faster speeds. This results in a wake up time for the microcontroller of less than

1µs, producing faster, more real time results.

4.2 Software

Now that we have looked at the hardware, we will need to research the software

aspects of our project that will be incorporated in the final design. This will include all

calculations used and devices controlled through executable code. From power

calculations and displays to user interfaces, all of our hardware will be implemented

using original code that our group will write. Since most, if not all, of our devices will be

controlled by one microcontroller or another, it would be beneficial to the group to

choose a microcontroller that is programmable in a programming language that is

already familiar with all of the group members.

4.2.1 Power Usage Calculations

Calculating the power usage will be done by calculating the amount of power in wattage

coming into the system vs. power going out of the system. If 5 watts of power is coming

into the system and 10 watts are going out of the system to power devices the

difference of the two will show the power consumption which will be displayed to the