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jeremybenn |
/*
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* This project contains an application demonstrating the use of the
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* FreeRTOS.org mini real time scheduler on the Luminary Micro LM3S811 Eval
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* board. See http://www.FreeRTOS.org for more information.
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*
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* main() simply sets up the hardware, creates all the demo application tasks,
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* then starts the scheduler. http://www.freertos.org/a00102.html provides
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* more information on the standard demo tasks.
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*
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* In addition to a subset of the standard demo application tasks, main.c also
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* defines the following tasks:
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*
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* + A 'Print' task. The print task is the only task permitted to access the
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* LCD - thus ensuring mutual exclusion and consistent access to the resource.
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* Other tasks do not access the LCD directly, but instead send the text they
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* wish to display to the print task. The print task spends most of its time
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* blocked - only waking when a message is queued for display.
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*
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* + A 'Button handler' task. The eval board contains a user push button that
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* is configured to generate interrupts. The interrupt handler uses a
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* semaphore to wake the button handler task - demonstrating how the priority
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* mechanism can be used to defer interrupt processing to the task level. The
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* button handler task sends a message both to the LCD (via the print task) and
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* the UART where it can be viewed using a dumb terminal (via the UART to USB
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* converter on the eval board). NOTES: The dumb terminal must be closed in
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* order to reflash the microcontroller. A very basic interrupt driven UART
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* driver is used that does not use the FIFO. 19200 baud is used.
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*
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* + A 'check' task. The check task only executes every five seconds but has a
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* high priority so is guaranteed to get processor time. Its function is to
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* check that all the other tasks are still operational and that no errors have
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* been detected at any time. If no errors have every been detected 'PASS' is
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* written to the display (via the print task) - if an error has ever been
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* detected the message is changed to 'FAIL'. The position of the message is
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* changed for each write.
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*/
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