|
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.
Port and interrupt handlers are same.
Illustration 4.4. External comparator on
port gives rising edge when signal lower than low reference.4: Flowchart Header files, Global variables and Defines
4.Illustration 4. External comparator port gives
rising edge when received signal higher than high reference.2 Interrupt handler functions
These functions are called from startup_ccs file.
Timer interrupt occurs when signal was received reserved time. Handler turn off
all interrupt and timer peripheral.
Handler disable all interrupt and timer, increase flag variable GPIO_INT, so
next value refer X_GPIO_INT Y_GPIO_INT. means that
some error could happen that have visibility between sensors. After that program continue place,
where was before this interrupt.5: Flowchart Interruption
handlers
22
. There were added declarations, which
link interrupts handler function and lines vector interrupts table with demanding
interruptions. When occur one of
that interrupt, signal was received. Then flag increased TIMER_INT defined
number and the result number which equal X_TIMER_INT Y_TIMER_INT
depends the measurement was axis
