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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.
all has done program is
waiting sequence status flag will set. Every cycle loop is
taken samples increased access appropriate position adc_array. Then adjust address value adc_array address with i
parameter and clear counting variable.
In these cycles program has called this function, then initialized local variables,
cleared counting variable and moved into loop. For
better optimization loop was unrolled and instead loop put here copy orders
with appropriate index number. Flowchart show loop cycle with copy data
from adc_value_0 array position content address increased parameter.
When first ADC sequence capturing first samples, there are before
sampling sequence complete. reach waiting condition later,
there can few not sampled periods receiving signal, which don’t affect our basic
signal amplitude correction. checked generated assembler code, that this
version takes clock cycles instead 32.
Data from the other sequences are taken similar way.
When program pass while waiting loop sequence ADC sequence status flag
is cleared and sequence triggered.10: Flowchart ADC sample function
27
. This sequence taking samples have μs
to get date from sequence first its samples are stored local array variable
adc_value_0 with fields.address first field adc_array. With clock frequency 12,5 MHz 200 clock cycles.
Illustration 4
