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Python Library to use with IO Zero 32 Raspberry Pi development board.
The example python files can be found in /ABElectronics_Python_Libraries/IOZero32/demos
Downloading and Installing the library
Python 3
To install the library you will need the Python3 build and install packages. To install them run the following command.
sudo apt update
sudo apt install python3-build python3-installer git
Download the ABElectronics_Python_Libraries to your Raspberry Pi:
git clone https://github.com/abelectronicsuk/ABElectronics_Python_Libraries.git
To install the python library navigate into the ABElectronics_Python_Libraries folder and run:
python3 -m build
sudo python3 -m installer dist/*.whl
Python 2
If you want to install the library on older versions of Linux using Python 2 you can run the following command.
sudo python setup.py install
If you have PIP installed you can install the library directly from GitHub with the following command replacing python2.7 with the version of Python on your computer:
sudo python2.7 -m pip install git+https://github.com/abelectronicsuk/ABElectronics_Python_Libraries.git
Using classes without installing the library
To use a specific part of our Python library in your project without installing the entire library, you can simply copy the needed class file into your project's directory. For example, to use the IO Zero 32, copy the IOZero32.py file from the IOZero32 directory to where your project files are located. After doing this, you can use the class in your program by adding an import statement at the beginning of your Python code. This allows you to directly utilize the class's functionality in your project.
from IOZero32 import IOZero32
Required Libraries
The library requires smbus2 or python-smbus to be installed
For Python 2.7:
sudo pip install smbus2
For Python 3:
sudo pip3 install smbus2
Classes:
IOZero32(address, bus)
Parameters:
address: i2c address for the target device. 0x20 to 0x27
bus (optional): I2C bus number (integer). If no value is set the class will try to find the i2c bus automatically using the device name.
Functions:
set_pin_direction(pin, value):
Sets the IO direction for an individual pin
Parameters:
pin: 1 to 16
value: 1 = input, 0 = output
Returns: null
get_pin_direction(pin)
Get the IO direction for an individual pin
Parameters:
pin: pin to read, 1 to 16
Returns: 1 = input, 0 = output
set_port_direction(port, value):
Sets the IO direction for the specified IO port
Parameters:
port: 0 = pins 1 to 8, 1 = pins 9 to 16
value: number between 0 and 255 or 0x00 and 0xFF. Each bit in the 8-bit number represents a pin on the port. 1 = input, 0 = output
Returns: null
get_port_direction(port):
Get the direction from an IO port
Parameters:
port: 0 = pins 1 to 8, 1 = pins 9 to 16
Returns: number between 0 and 255 (0xFF)
set_bus_direction(value):
Sets the IO direction for all pins on the bus
Parameters:
value: 16-bit number 0 to 65535 (0xFFFF). For each bit 1 = input, 0 = output
Returns: null
get_bus_direction()
Get the direction for an IO bus
Returns: 16-bit number 0 to 65535 (0xFFFF). For each bit 1 = input, 0 = output
write_pin(pin, value)
Write to an individual pin 1 - 16
Parameters:
pin: 1 to 16
value: 1 = logic high, 0 = logic low
Returns: null
write_port(port, value)
Write to all pins on the selected port
Parameters:
port: 0 = pins 1 to 8, 1 = pins 9 to 16
value: number between 0 and 255 or 0x00 and 0xFF. Each bit in the 8-bit number represents a pin on the port. 1 = logic high, 0 = logic low
Returns: null
write_bus(value)
Write to all pins on the selected bus
Parameters:
value: 16-bit number 0 to 65535 (0xFFFF). For each bit 1 = logic high, 0 = logic low
Returns: null
read_pin(pin)
Read the value of an individual pin 1 - 16
Parameters:
pin: 1 to 16
Returns: 0 = logic low, 1 = logic high
read_port(port)
Read all pins on the selected port
Parameters:
port: 0 = pins 1 to 8, 1 = pins 9 to 16
Returns: number between 0 and 255 or 0x00 and 0xFF. Each bit in the 8-bit number represents a pin on the port. 0 = logic low, 1 = logic high
read_bus()
Read all pins on the bus
Returns: 16-bit number 0 to 65535 (0xFFFF) Each bit in the 16-bit number represents a pin on the port. 0 = logic low, 1 = logic high
set_pin_polarity(pin, value)
Set the polarity of the selected pin
Parameters:
pin: 1 to 16
value: 0 = same logic state of the input pin, 1 = inverted logic state of the input pin
Returns: null
get_pin_polarity(pin)
Get the polarity of the selected pin
Parameters:
pin: pin to read, 1 to 16
Returns: 0 = same logic state of the input pin, 1 = inverted logic state of the input pin
set_port_polarity(port, value)
Set the polarity of the pins on a selected port
Parameters:
port: 0 = pins 1 to 8, 1 = pins 9 to 16
value: number between 0 and 255 or 0x00 and 0xFF. Each bit in the 8-bit number represents a pin on the port. 0 = same logic state of the input pin, 1 = inverted logic state of the input pin
Returns: null
get_port_polarity(port):
Get the polarity for the selected IO port
Parameters:
port: 0 = pins 1 to 8, 1 = pins 9 to 16
Returns: number between 0 and 255 (0xFF)
set_bus_polarity(value)
Set the polarity of the pins on the bus
Parameters:
value: 16-bit number 0 to 65535 (0xFFFF). For each bit 0 = same logic state of the input pin, 1 = inverted logic state of the input pin
Returns: null
get_bus_polarity()
Get the polarity of the pins on the bus
Returns: 16-bit number 0 to 65535 (0xFFFF). For each bit 0 = same logic state of the input pin, 1 = inverted logic state of the input pin
Usage
To use the IO Zero 32 library in your code you must first import the library:
from IOZero32 import IOZero32
Next, you must initialise the IOZero32 object with the I2C address of the I/O controller chip. The default addresses for the IO Zero 32 are 0x20 and 0x21:
bus1 = IOZero32(0x20)
We will read the inputs 1 to 8 from bus 1 so set port 0 as inputs.
bus1.set_port_direction(0, 0xFF)
You can now read pin 1 with:
print('Pin 1: ' + str(bus1.read_pin(1)))
