Joy-it RB-P-XPLR-SET handleiding

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Joy-it

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Handleiding

. DISTANCE DISPLAY

In our first project, our goal is to build an ultrasonic rangefinder that visualizes distances on our TFT display. This project is a great introduction to sensing

and visualizing data with your Raspberry Pi Pico.

ULTRASONIC SENSOR: A transmitter emits an ultrasonic wave and measures the time until it is reflected

and arrives back at the transmitter. As the speed of sound is known in various media such as air (343 m/s

at 20 °C) and water (1,484 m/s), the distance to the reflecting surface can be calculated (halving the transit

time, as the distance there and back was measured). A pulse from the microcontroller at the trigger input

triggers a sequence of eight short ultrasonic pulses. As soon as the signal is received again, the echo output

briefly goes high. The time between the trigger and the echo signal corresponds to the transit time. Distance

measurement is possible in the range from about 2 cm to 400 cm and is quite precise as long as the reflecting

surface is as hard and even as possible. So materials such as carpeting can even prevent a measurement.

Since the ultrasonic sensor is a sensor that requires a power supply of 5 V, but the Raspberry Pi Pico

can only process 3.3 V signals without any problems, it is necessary to down-convert the signal voltage

to avoid damage. We achieve this by connecting our yellow LED in series on the breadboard and using

it to down-convert our signal. The LED also functions as a signal indicator for the active echo signal.

Further details on LEDs can also be found in chapter 5.5.

ATTENTION! For this project it is necessary to set the switches

for the RELAY and the DHT to OFF and the switch for the TFT

DISPLAY to ON.

RASPBERRY PI PICO ULTRASONIC SENSOR

3V3

GP17

GP16

GND

VCC

Trig

Echo

GND

Bekijk gratis de handleiding van Joy-it RB-P-XPLR-SET, stel vragen en lees de antwoorden op veelvoorkomende problemen, of gebruik onze assistent om sneller informatie in de handleiding te vinden of uitleg te krijgen over specifieke functies.