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