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Kategorie: Diplomové, bakalářské práce |
Tento dokument chci!
Práce popisuje principy a problémy při realizaci ultrazvukového anemometru. Je popsán princip výpočtu rychlosti větru a následné korekce výpočtu. Pro realizaci jsou využity ultrazvukové sensory a microcontrolér ARM Cortex-M3. Práce se zabývá generováním PWM signálu, jeho analogovou filtrací, zesílením a odvysíláním. Na přijímací straně jeto nízkonapěťový zesilovač a komparátor. Vyvíjený kód je popsán pomocí vývojového diagramu.
For creation this diagrams LibreOffice Draw was used. CCS was installed from
kit included CD. First function preparing PWM for measurement chosen
axis. Their behavior controlled with flag global variable with its
definitions for every value.
4.
After this initialization main function called. Variable flag has defined all its states above. Its value 31250 refers 2,5 with 12,5 MHz clock
speed. It’s divided into
sections and functions was illustrated above.4. Then
interrupt handler functions can found.1 Header files, Global variable and Defines
Included header files are chosen for used peripherals and microcontroller.
Then function capture time from timer called. the beginning initialization functions takes place. All orders, processes and functions
are accompanied with lot comments.2 TI.4. [15]
Within development code Stellaris peripheral driver library user's guide was
great aid [14]. The rest are function calculate
peak peak value from ADC sequence, function make averages peak peak
values and wind calculation function. All them are called from main function, where the program
starts.
It let know every time what was done and what has done. Variable adc_array is
used save here samples from converter. Flowchart take account whole code
inside anemometer file, which was created for this application. Every part will be
described separately below. These conditions test flag global
variable and inside each concretes functions are called. the
beginning the main are local variables with calling initialization function.4 Flowcharts
To describe how works our anemometer flowchart was created. After digital input port interruption ADC sample function called. There are few condition inside. contain basic description all peripherals programming API. Constant variable timer_load_set used
to set time for timer interruption.3 Code development
Code was developed Code composer studio 4. also
includes example use every peripherals.
On the bottom the code main function with its infinite while loop. permit us
using drive Stellaris driver API functions.
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. Then after timer interrupt function inform that measurement hasn’t done and sets
flag start again. Below interrupt handler functions the rest of
functions can found.
All code was written into anemometer file. From time time function calculate
temperature called. also contain programming examples, driver libraries and and header
files, which form application programming interface API. Code continue with
a component functions. Behind
that while loop start. It’s divided few section the beginning.
After release notes include files, global variable with its defines can found.
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