exboard 1.0.5

A exboard package for AIBOX

GPIO Control Library for Jetson Orin Nano and RK3399 Pro

https://github.com/jiangyangcreate/exboard

Overview

This Python library provides an easy-to-use interface for controlling the GPIO pins on Jetson Orin Nano and RK3399 Pro. It simplifies the process of configuring, reading, and writing GPIO pins, making it suitable for various hardware projects and applications.

Features

• Support for Jetson Orin Nano and RK3399 Pro platforms.
• Automatic detection of the operating system (Ubuntu or Debian).
• Easy GPIO configuration (input/output).
• Read and write GPIO pin states.
• Clean and simple API.

USE

We use Python code to operate sensors such as cameras, temperature sensors, and more. These sensors help us gather environmental information to make appropriate decisions.

For sensors other than the camera, we use the I2C protocol. The I2C protocol is a serial bus that can connect multiple devices simultaneously. We read sensor data via the I2C protocol. The relevant code must be run with sudo privileges.

For detailed usage instructions, refer to the interface documentation section at the end of this document. Here, we will mainly discuss some simple examples and precautions.

How to Call Sensors?

1. Import Modules

The latest version is Version: 1.0.5

sudo pip3 install exboard==1.0.5

When using functions, we import the specified module using the import keyword, or we can use from module_name import function/class/method_name:

from exboard import FlameSensor
from exboard import MQGasSensor
from exboard import PhotosensitiveSensor
from exboard import RGB
from exboard import Ultrasound
from exboard import SoundSensor
from exboard import Servos
from exboard import RotaryPotentionmeter

2. Instantiate Sensors

The following code, named sensor.py, imports gas, photosensitive, sound, and ultrasonic sensors, and then calls the read method to get the sensor data through the instantiated objects.

Note: Data is obtained through the read method. To continuously acquire data, you need to use a loop. Also, remember to add time.sleep to avoid data retrieval being too fast to be readable.

from exboard import MQGasSensor
from exboard import PhotosensitiveSensor
from exboard import Ultrasound
from exboard import SoundSensor
import time

sensor2 = MQGasSensor()
sensor3 = PhotosensitiveSensor()
sound4 = SoundSensor()
us = Ultrasound()
while True:
    a2 = sensor2.read()
    a3 = sensor3.read()
    a4 = sound4.read()
    dist = us.read()
    print(
        "Gas {} Photosensitive {} Sound {} Ultrasound {} ".format(
            a2,
            a3,
            a4,
            dist,
        )
    )
    time.sleep(0.2)

3. Execute Code

You have already learned the basics of the terminal. Now you can use the cd command to switch to your working directory and then run your code with the python command.

Here is a basic example. Note that spaces are meaningful, so make it a habit not to add or remove any:

sudo is a command used to elevate permissions, as our code needs to operate hardware, it requires elevated permissions.
python3 sensor.py is the command to execute the code, indicating that Python is used to run the sensor.py file.

sudo python3 sensor.py

All code involving sensors other than the camera needs to be run with sudo privileges.

4. Results

After executing the code, you will see the sensor data continuously printed in the terminal.

Interface Documentation

RaspberryPi-Sensor-Board Custom Interface Extension Board

Sensor Name	Interface 1	Interface 2	Calling Method
LED Ring	D9	D10	RGB
NFC	SDA	SCL	RC522
Sound Sensor	A0	D22	SoundSensor
Air Quality Sensor (Old)	A1	D23	MQGasSensor
Air Quality Sensor (New)	A2	D24	MQGasSensor
Photosensitive Sensor	A4		PhotosensitiveSensor
Ultrasonic Sensor	D4 (trig)	D5 (echo)	Ultrasound
Camera Pan-Tilt X Axis	D12		servos
Camera Pan-Tilt Y Axis	D13		servos
Camera Pan-Tilt LED	D14		LED
Left Knob	A5		RotaryPotentionmeter
Right Knob	A6		RotaryPotentionmeter
Left Button	D25		GPIO
Middle Button	D26		GPIO
Right Button	D27		GPIO
Free Expansion Port Upper Left	D16		Determined by sensor
Free Expansion Port Lower Left	A7		Determined by sensor
Free Expansion Port Middle	A3	D25	Shares D25 signal with left button
Free Expansion Port Upper Right	D17		Determined by sensor
Free Expansion Port Lower Right	D18		Determined by sensor

The air quality sensor might be connected to A1| D23 or A2| D24. To determine the exact sensor connection, you can check the MQGasSensor method and input different interface combinations to see if there is data.

The Free Expansion Port Middle uses A3| D25, where D25 shares the signal line with the left button. If you connect the Flame Sensor to the Free Expansion Port Middle, this sensor has GVAD four pins, where A can return the flame size, and D can return the presence of a flame.

Both of the following conditions will generate a signal on D25:

• Pressing the left button switch
• The flame sensor detects a flame

GPIO

This class is used to handle general-purpose input/output (GPIO) pins. It receives a pin number and other parameters 'out' or 'in', and returns a periphery.GPIO object. Operations that can be performed on periphery.GPIO include:

• write(value): Write a boolean value
• read(): Read the current value of the pin

Example:

gpio17 = GPIO(17, 'out')
gpio17.write(True) # Power on
gpio17.write(False) # Power off

gpio18 = GPIO(18, 'in')
gpio18.read()

ADC

This class is used to handle Analog to Digital Converters (ADC). It receives a pin number and creates an I2C object to read the ADC's value. It has a method read to read the current value of the ADC.

Example:

adc = ADC(0)
value = adc.read()
print(value)

LED

This class is used to handle an LED. It receives a pin number and creates a GPIO object to control the LED. It has two methods: on and off to turn the LED on and off.

Example:

led = LED(17)
led.on()
led.off()

RC522

This class is used to handle the RC522 RFID reader. It has two methods: scan and read. The scan method scans for RFID cards, and the read method reads data from the scanned RFID card.

Example:

rc522 = RC522()
tagType, uid = rc522.scan()
if uid:
    data = rc522.read(uid, 8)
    print(data)

RGB

This class is used to handle RGB LED strips. It has two methods: set and send_frame. The set method receives a list of colors and sends them to the LED strip. The send_frame method sends a complete frame to the LED strip.

Example:

rgb = RGB()
rgb.set([(255, 0, 0), (0, 255, 0), (0, 0, 255)])

Ultrasound

This class is used to handle ultrasonic sensors. It receives the pin numbers for the trigger and echo pins and creates two GPIO objects to control these pins. It has a method read to read the current distance from the ultrasonic sensor, with the value in centimeters.

Example:

ultrasound = Ultrasound(4, 5)
distance = ultrasound.read()
print(distance)

SoundSensor

This class is used to handle sound sensors. It receives the pin numbers for an analog pin and a digital pin and creates a GPIO object and an ADC object to control these pins. It has a method read to read the current state (presence of sound) and value (sound level) from the sound sensor.

Example:

sound_sensor = SoundSensor(0, 22)
signal, value = sound_sensor.read()
print(signal, value)

PhotosensitiveSensor

This class is used to handle photosensitive sensors. It receives the pin number for an analog pin and creates an ADC object to read the value of the pin. It has a method read to read the current value from the photosensitive sensor.

Example:

photosensitive_sensor = PhotosensitiveSensor(4)
value = photosensitive_sensor.read()
print(value)

SoilMoistureSensor

This class is used to handle soil moisture sensors. It receives the pin number for an

analog pin and creates an ADC object to read the value of the pin. It has a method read to read the current value from the soil moisture sensor.

Example:

soil_moisture_sensor = SoilMoistureSensor(5)
value = soil_moisture_sensor.read()
print(value)

FlameSensor

This class is used to handle flame sensors. It receives the pin number for an analog pin and creates an ADC object to read the value of the pin. It has a method read to read the current value from the flame sensor.

Example:

flame_sensor = FlameSensor(7)
value = flame_sensor.read()
print(value)

TemperatureSensor

This class is used to handle temperature sensors. It receives the pin number for an analog pin and creates an ADC object to read the value of the pin. It has a method read to read the current value from the temperature sensor.

Example:

temperature_sensor = TemperatureSensor(6)
value = temperature_sensor.read()
print(value)

Servos

This class is used to handle servo motors. It receives the pin numbers for two PWM pins and creates PWM objects to control these pins. It has methods set_angle and set_speed to control the angle and speed of the servo motors.

Example:

servos = Servos(12, 13)
servos.set_angle(90)
servos.set_speed(1)

RotaryPotentionmeter

This class is used to handle rotary potentiometers. It receives the pin number for an analog pin and creates an ADC object to read the value of the pin. It has a method read to read the current value from the rotary potentiometer.

Example:

rotary_potentiometer = RotaryPotentionmeter(5)
value = rotary_potentiometer.read()
print(value)