GPS Enhanced PFD System Software PresentationEric Grossmann

Presentation Summary

•General System Specifications

•Timeslice Kernel Tasks

•Modules

•Data Flow Diagram

•Individual Task Descriptions

•CPU Load

• MCU PSOC 1 CY8C24794• 4 Digital Blocks & 6 Analog Blocks

• Bus Frequency: 24 MHz • Timeslice Kernel

• Timeslice Period:100 ms• Memory Available:

• 16k Flash • 1k RAM

• Memory Requirement:• Less than 1k Flash• 1k RAM

•General System Specifications

• Startup Task• Acceleration Detect Task• Immersion Detect Task• Switch Detect Task• GPS Rx Task• Tx Task

•Timeslice Kernel Tasks

• Initializes the system

• Execution Time:• 100ms worst case.

• Period:• Once at Startup

•Startup Task

• Observes hex output from the sensor• Passes a hex output to the MCU.• Period 100ms• Execution Time 5μs

•Acceleration Detect Task

• Observes changing voltage from the sensor• Converts the voltage into digital format• Passes voltage level as a hex output to the MCU.• Period 100ms• Execution Time 5μs

• Immersion Detect Task

• Waits and recognizes a voltage level on a toggle switch. De-bounces the switch.

• Period: 1s • Execution Time: 10μs

•Switch Detect Task

• Observes hex output from the sensor• Passes a hex output to the MCU.• Period 300s (sporadic)• Execution Time 5μs

•GPS Rx Task

• Observes hex output from the MCU• Passes a hex output to the Transmitter module.• Period 300ms (sporadic)• Execution Time 5μs

•Tx Task

•Modules

Module TasksPublic

Functions & Data

GPSPFD.c Startup TaskAcceleration Detect TaskImmersion Detect TaskGPS Rx TaskTx Task

GLevelOvrBrdGPSDataRescMe()GPSID

Switch.c Switch Detect Task SwitchState

• Max CPU Load

• 5us/100ms + 5us/100ms + 10us/1000ms + 5us/300000ms + 5us/300000ms

= 0.01% CPU Load

•CPU Load

GPS Module GPS Rx Task GPSData

Accelerometer Sensor

Acceleration Detect

TaskGLevel

Immersion Sensor

Immersion Detect

TaskOvrBrd

Toggle SwitchSwitch Detect Task

SwitchState

Transmitter Module Tx TaskGPSID

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•Data Flow DiagramHardware GPSPFD.c