GPIO_NXP_Arduino

GPIO device operation sample code for Arduino

Note This library works with I2C_device library together. Please be sure the I2C_device library is imported in your environment before trying to build.

PCAL6416AEV-ARD (on Arduino), PCAL6534EV-ARD, PCAL6524EV-ARD and PCAL6408A-ARD (far side from left to right) : Arduino® Shield Evaluation Boards for GPIO

What is this?

An Arduino library for I²C GPIO-expander with sample code.
This library provides simple API to control GPIO device IO bits Include device name header file (PCAL6408A.h, PCAL6416A.h, PCAL6424.h, PCAL6434.h, PCA9554.h, and/or PCA9555.h) to use those class libraries.

Basic operation

With GPIO_NXP_Arduino library, parallel output can be controlled by next sample code.

#include <PCAL6416A.h>

PCAL6416A gpio;

void setup() {
  gpio.begin(GPIO_base::ARDUINO_SHIELD);
  Wire.begin();
  gpio.config(0, 0x00); //  Port0 is configured as output
}

void loop() {
  static int count = 0;
  gpio.output(0, count++);  //  Output to port0 
  delay(10);
}

To operate the port for input, the IO pins can be configured bit by bit.
The config bit for output is 0 and input is 1. When the bit 0 to 4 on port 0 are configured as input and rest are output, the configuration can be done as..

gpio.config(0, 0x0F); // bit 0 to 4 are '1' to set those bits are input

For multiple port setting, the configuration can be done with array.
Following is a sample to set 2 port in PCAL6416A as port0=output, port1=input.

#include <PCAL6416A.h>
PCAL6416A gpio;

void setup() {
  uint8_t io_config_and_pull_up[] = {
    0x00,  // Configure port0 as OUTPUT
    0xFF,  // Configure port1 as INTPUT
  };

  gpio.config(io_config_and_pull_up);                   //  Port0 as OUTPUT, port1 as INPUT
}

void loop() {
  int input1 = gpio.input(1); //  Read port0 input
  gpio.output(0, input1);     //  Output to port0
}

Option: Operation with PORT class

As an option, PORT class is available to operate the GPIO port independently. With this class, each port input and output can be done with = operator.

#include <PCAL6416A.h>
#include <PORT.h>

PCAL6416A gpio;
PORT port[] = { PORT(gpio, 0),
                PORT(gpio, 1) };

void setup() {
  Wire.begin();

  port[0].config(0x00);  //  Configure port0 as OUTPUT
  port[1].config(0xFF);  //  Configure port1 as INPUT
}

void loop() {
  int input1 = port[1];  //  Read port0 input
  port[0] = input1;      //  Output to port0
  
  // if you want to do like port[0] = port[1], cast the port instance. It should be like..
  // port[0] = (int)port[1];	

  delay(100);
}

Supported devices

Type#	Header file	IO bits	Features	Interface	Evaluation board
PCAL6408A	PCAL6408A.h	8	Low-Voltage Translating, 8-Bit I²C-Bus/SMBus I/O Expander	I²C Fast-mode Plus (1MHz)	PCAL6408A 8-Bit GPIO Arduino® Shield
PCAL6416A	PCAL6416A.h	16	Low-Voltage Translating 16-Bit I²C-Bus/SMBus I/O Expander	I²C Fast-mode Plus (1MHz)	PCAL6416A 16-bit GPIO Arduino® Shield
PCAL6424	PCAL6424.h	24	Ultra-Low-Voltage Translating 24-Bit Fm+ I²C-Bus/SMBus I/O Expander	I²C Fast-mode Plus (1MHz)	PCAL6524EV 24-Bit GPIO Arduino® Shield
PCAL6434	PCAL6434.h	34	Ultra-Low-Voltage, Level Translating, 34-Bit I2C-Bus/SMBus I/O Expander	I²C Fast-mode Plus (1MHz)	PCAL6534EV 34-Bit GPIO Arduino® Shield
PCAL9722	PCAL9722.h	22	22-Bit SPI I/O Expander with Agile I/O Features	SPI (5MHz)	PCAL6534HV 22-Bit GPIO Arduino® Shield
PCA9554 not tested	PCA9554.h	8	8-Bit I²C-Bus and SMBus I/O Port with Interrupt	I²C Fast-mode (400Hz)	---
PCA9555	PCA9555.h	16	16-Bit I²C-Bus and SMBus I/O Port with Interrupt	I²C Fast-mode (400Hz)	---

Getting started

Use Library manager in Arduino IDE for easy install

What's inside?

Examples

Examples are provided as scketch files.

How to use?

After library install, Choose menu on Arduino-IDE: File→Examples→GPIO_NXP_Arduino→ sketch for your try

List of sample code

For PCAL6xxx GPIO Arduino® Shield evaluation boards

Sketch	Folder/Target	Feature
PCAL6408A_simple_OUT	PCAL6408A	Simple sample for just output counter value
PCAL6408A_simple_IN_OUT	PCAL6408A	Blink LED to show which buton pressed. Read value shown on serial terminal also
PCAL6408A_interrupt	PCAL6408A	IO demo with interrupt
PCAL6416A_simple_OUT	PCAL6416A	Simple sample for just output counter value
PCAL6416A_simple_IN_OUT	PCAL6416A	Blink LED to show which buton pressed. Read value shown on serial terminal also
PCAL6416A_interrupt	PCAL6416A	IO demo with interrupt
PCAL6524A_simple_OUT	PCAL6524	Simple sample for just output counter value
PCAL6524_simple_IN_OUT	PCAL6524	Blink LED to show which buton pressed. Read value shown on serial terminal also
PCAL6524_interrupt	PCAL6524	IO demo with interrupt
PCAL6534_simple_OUT	PCAL6534	Simple sample for just output counter value
PCAL6534_simple_IN_OUT	PCAL6534	Blink LED to show which buton pressed. Read value shown on serial terminal also
PCAL6534_interrupt	PCAL6534	IO demo with interrupt
PCAL9722_simple_OUT	PCAL9722	Simple sample for just output counter value
PCAL9722_simple_IN_OUT	PCAL9722	Blink LED to show which buton pressed. Read value shown on serial terminal also
PCAL9722_interrupt	PCAL9722	IO demo with interrupt

For non-ARD boards

Sketch	Folder/Target	Feature
PCA9555_port0_OUT	PCA9555	Simple sample for just output counter value
PCA9555_port0_OUT_and_port1_IN	PCA9555	To check output and input
PCA9555_interrupt_on_port1	PCA9555	Interrupt check

For PORT class usage samples

As an option, the PORT class can be used for GPIO devices.
Each port on GPIO devices can be an instance to operate by = operator.

Sketch	Folder/Target	Feature
PCAL6408A_PORT_OUT	PORT_class/PCAL6408A/	Simple sample for just output counter value using PORT class
PCAL6408A_PORT_IN_OUT	PORT_class/PCAL6408A	Blink LED to show which buton pressed. Read value shown on serial terminal also using PORT class
PCAL6416A_PORT_OUT	PORT_class/PCAL6416A	Simple sample for just output counter value using PORT class
PCAL6416A_PORT_IN_OUT	PORT_class/PCAL6416A	Blink LED to show which buton pressed. Read value shown on serial terminal also using PORT class
PCAL6524A_PORT_OUT	PORT_class/PCAL6524	Simple sample for just output counter value using PORT class
PCAL6524_PORT_IN_OUT	PORT_class/PCAL6524	Blink LED to show which buton pressed. Read value shown on serial terminal also using PORT class
PCAL6534_PORT_OUT	PORT_class/PCAL6534	Simple sample for just output counter value using PORT class
PCAL6534_PORT_IN_OUT	PORT_class/PCAL6534	Blink LED to show which buton pressed. Read value shown on serial terminal also using PORT class

TIPS

If you need to use different I²C bus on Arduino, it can be done like this. This sample shows how the Wire1 on Arduino Due can be operated.

include <PCAL6408A.h>

PCAL6408A gpio(Wire1);

void setup() {
  Wire1.begin();

Document

For details of the library, please find descriptions in this document.

References

Related libraries

Library	Feature	Target devices	Required library
GPIO_NXP_Arduino	GPIO libraries	PCAL6408A, PCAL6416A, PCAL6524, PCAL6534, PCA9555, PCA9554	I2C_device_Arduino
LCDDriver_NXP_Arduino	LCD driver libraries	PCA8561	I2C_device_Arduino
LEDDriver_NXP_Arduino	LED driver libraries	PCA9955B, PCA9956B, PCA9957	I2C_device_Arduino
MUX_SW_NXP_Arduino	I²C mux/switch libraries	PCA9846	I2C_device_Arduino
RTC_NXP_Arduino	RTC libraries	PCF2131, PCF85063A	I2C_device_Arduino
TempSensor_NXP_Arduino	Temperature sensor libraries	LM75B, PCT2075, P3T1085	I2C_device_Arduino
I2C_device_Arduino	Base library for I²C operations	none (can be applied as base class for all I²C targets)	---