IO Zero 32 Node JS Library

Node.js Library to use with IO Zero 32 Raspberry Pi development board.

Install

To download to your Raspberry Pi type in the terminal:

git clone https://github.com/abelectronicsuk/ABElectronics_NodeJS_Libraries.git

The IO Zero 32 library is located in the /lib/iozero32/ directory

The example files are located in the /examples/iozero32/ directory

The IO Zero 32 library requires the i2c-bus library to run.

Install from npm package repository i2c-bus with

npm install i2c-bus

Classes:

IOZero32(address)

Parameters:
address: (number) i2c address for the target device. 0x20 to 0x27

Functions:

setPinDirection(pin, direction):

Sets the IO direction for an individual pin
Parameters:
pin: (number) 1 to 16
direction: (number) 1 = input, 0 = output
Returns: null

getPinDirection(pin)

Get the IO direction for an individual pin
Parameters:
pin: (number) pin to read, 1 to 16
Returns: (number) 1 = input, 0 = output

setPortDirection(port, direction): 

Sets the IO direction for the specified IO port
Parameters:
port: (number) 0 = pins 1 to 8, 1 = pins 9 to 16
direction: (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

getPortDirection(port): 

Get the direction from an IO port
Parameters:
port: (number) 0 = pins 1 to 8, 1 = pins 9 to 16
Returns: (number) between 0 and 255 (0xFF)

setBusDirection(direction): 

Sets the IO direction for all pins on the bus
Parameters:
direction: (number) 16-bit number 0 to 65535 (0xFFFF). For each bit 1 = input, 0 = output
Returns: null

getBusDirection()

Get the direction for an IO bus
Returns: (number) 16-bit number 0 to 65535 (0xFFFF). For each bit 1 = input, 0 = output

writePin(pin, value)

Write to an individual pin 1 - 16
Parameters:
pin: (number) 1 to 16
value: (number) 1 = logic high, 0 = logic low
Returns: null

writePort(port, value)

Write to all pins on the selected port
Parameters:
port: (number) 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

writeBus(value)

Write to all pins on the selected bus
Parameters:
value: (number) 16-bit number 0 to 65535 (0xFFFF). For each bit 1 = logic high, 0 = logic low
Returns: null

readPin(pin)

Read the value of an individual pin 1 - 16
Parameters:
pin: (number) 1 to 16
Returns: (uint8_t) 0 = logic low, 1 = logic high

readPort(port)

Read all pins on the selected port
Parameters:
port: (number) 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

readBus()

Read all pins on the bus
Returns: (number) 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

setPinPolarity(pin, polarity)

Set the polarity of the selected pin
Parameters:
pin: (number) 1 to 16
polarity: (number) 0 = same logic state of the input pin, 1 = inverted logic state of the input pin
Returns: null

getPinPolarity(pin)

Get the polarity of the selected pin
Parameters:
pin: (number) pin to read, 1 to 16
Returns: (number) 0 = same logic state of the input pin, 1 = inverted logic state of the input pin

setPortPolarity(port, polarity)

Set the polarity of the pins on a selected port
Parameters:
port: (number) 0 = pins 1 to 8, 1 = pins 9 to 16
polarity: (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

getPortPolarity(port): 

Get the polarity for the selected IO port
Parameters:
port: (number) 0 = pins 1 to 8, 1 = pins 9 to 16
Returns: (number) between 0 and 255 (0xFF)

setBusPolarity(polarity)

Set the polarity of the pins on the bus
Parameters:
polarity: (number) 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

getBusPolarity()

Get the polarity of the pins on the bus
Returns: (number) 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:

var IOZero32 = require('../../lib/iozero32/iozero32');

Next, you must initialise the IOZero32 object

var bus1 = new IOZero32(0x20);

We will read the inputs 1 to 8 from bus 1 so set port 0 to be inputs

bus1.setPortDirection(0, 0xFF);

You can now read pin 1 with:

console.log('Pin 1: %d', bus1.readPin(1));