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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.
4. Variable flag has defined all its states above.4.2 TI. Every part will be
described separately below.
Then function capture time from timer called.
On the bottom the code main function with its infinite while loop.
After release notes include files, global variable with its defines can found.
4. CCS was installed from
kit included CD. also
includes example use every peripherals. Code continue with
a component functions. Behind
that while loop start. Flowchart take account whole code
inside anemometer file, which was created for this application. The rest are function calculate
peak peak value from ADC sequence, function make averages peak peak
values and wind calculation function. Below interrupt handler functions the rest of
functions can found. the beginning initialization functions takes place. From time time function calculate
temperature called. also contain programming examples, driver libraries and and header
files, which form application programming interface API.1 Header files, Global variable and Defines
Included header files are chosen for used peripherals and microcontroller. First function preparing PWM for measurement chosen
axis.3 Code development
Code was developed Code composer studio 4. It’s divided into
sections and functions was illustrated above.
For creation this diagrams LibreOffice Draw was used. contain basic description all peripherals programming API. Their behavior controlled with flag global variable with its
definitions for every value.
It let know every time what was done and what has done. permit us
using drive Stellaris driver API functions. There are few condition inside.
21
.4. the
beginning the main are local variables with calling initialization function. These conditions test flag global
variable and inside each concretes functions are called. Its value 31250 refers 2,5 with 12,5 MHz clock
speed. Constant variable timer_load_set used
to set time for timer interruption.4 Flowcharts
To describe how works our anemometer flowchart was created. Then
interrupt handler functions can found.
After this initialization main function called. All orders, processes and functions
are accompanied with lot comments. It’s divided few section the beginning. Variable adc_array is
used save here samples from converter. Then after timer interrupt function inform that measurement hasn’t done and sets
flag start again. [15]
Within development code Stellaris peripheral driver library user's guide was
great aid [14].
All code was written into anemometer file. All them are called from main function, where the program
starts
