FinalProjectCriticalDesignReview
Nguyen,Kevin
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SystemDescription
Thesystemisacalculatorthatperformssimpleintegeraddition/subtractionand
displaystheresultonanLCDdisplay:
o Inputs:Theusershallprovidekeypadpresseswhicharecapturedbythe
microcontroller'sGPIOpinsconnectedtothekeypad
o Function:
o Eachkeypadinputisdecodedandidentifiedasoperator,operand,orcommand
o OperatorsandoperandsarebufferedanddisplayedontheLCDinreal-time
Operandsareconstructedfromaseriesofdigitkeypresses.
o AnequaloroperatorcommandkeypressinstructstheALUtoperformthe
arithmeticoperation.
o Outputs:TheLCDdriverconvertstheALUresultintoabinaryformattobe
shownontheLCDdisplay.GPIOfunctionsareusedtodrivethepinsconnected
totheLCDdisplay.
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OverallSystemBlockDiagram
4
OverallSystemSchematic
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SubsystemsOverview
Keypad
o 4x4arrayofkeyswhichareconnectedtoMCU
Decoder/Buffers
o Decodeskeypadinputsandstoresintobuffer
ALU
o Performsintegeraddition/subtraction
LCD&GPIODrivers
o ConvertsstringsintoformatthatcanbedrivenoutonGPIO
LCDDisplay
o DisplaysdataonLCDscreenandhasacontrollerwhichcanbeconfigured
intodifferentmodesofoperation
