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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.
After digital input port interruption ADC sample function called.
On the bottom the code main function with its infinite while loop.1 Header files, Global variable and Defines
Included header files are chosen for used peripherals and microcontroller.4. Constant variable timer_load_set used
to set time for timer interruption. These conditions test flag global
variable and inside each concretes functions are called. the beginning initialization functions takes place.3 Code development
Code was developed Code composer studio 4.
4. Flowchart take account whole code
inside anemometer file, which was created for this application. Its value 31250 refers 2,5 with 12,5 MHz clock
speed. Variable adc_array is
used save here samples from converter. Behind
that while loop start. The rest are function calculate
peak peak value from ADC sequence, function make averages peak peak
values and wind calculation function.2 TI. the
beginning the main are local variables with calling initialization function. All them are called from main function, where the program
starts. Every part will be
described separately below. Then after timer interrupt function inform that measurement hasn’t done and sets
flag start again. All orders, processes and functions
are accompanied with lot comments. From time time function calculate
temperature called. Then
interrupt handler functions can found. also contain programming examples, driver libraries and and header
files, which form application programming interface API.
21
. also
includes example use every peripherals.
For creation this diagrams LibreOffice Draw was used.
It let know every time what was done and what has done. There are few condition inside.
After release notes include files, global variable with its defines can found. Variable flag has defined all its states above. permit us
using drive Stellaris driver API functions. Their behavior controlled with flag global variable with its
definitions for every value. It’s divided into
sections and functions was illustrated above.
After this initialization main function called. CCS was installed from
kit included CD.
4.
Then function capture time from timer called.4 Flowcharts
To describe how works our anemometer flowchart was created. [15]
Within development code Stellaris peripheral driver library user's guide was
great aid [14]. Code continue with
a component functions. It’s divided few section the beginning. contain basic description all peripherals programming API.
All code was written into anemometer file.4. Below interrupt handler functions the rest of
functions can found. First function preparing PWM for measurement chosen
axis