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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.
When first ADC sequence capturing first samples, there are before
sampling sequence complete. all has done program is
waiting sequence status flag will set.
In these cycles program has called this function, then initialized local variables,
cleared counting variable and moved into loop. This sequence taking samples have μs
to get date from sequence first its samples are stored local array variable
adc_value_0 with fields. With clock frequency 12,5 MHz 200 clock cycles.
When program pass while waiting loop sequence ADC sequence status flag
is cleared and sequence triggered. Flowchart show loop cycle with copy data
from adc_value_0 array position content address increased parameter. Then adjust address value adc_array address with i
parameter and clear counting variable. For
better optimization loop was unrolled and instead loop put here copy orders
with appropriate index number. Every cycle loop is
taken samples increased access appropriate position adc_array.10: Flowchart ADC sample function
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.address first field adc_array.
Illustration 4. checked generated assembler code, that this
version takes clock cycles instead 32.
Data from the other sequences are taken similar way. reach waiting condition later,
there can few not sampled periods receiving signal, which don’t affect our basic
signal amplitude correction
