Manuel Caballero / PCF8574

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PCF8574 Class Reference
Public Types | Public Member Functions

PCF8574 Class Reference

Example: More...

#include <PCF8574.h>

Public Types

enum  PCF8574_address_t {
  PCF8574_ADDRESS_0 = ( 0x20 << 1 ), PCF8574_ADDRESS_1 = ( 0x21 << 1 ), PCF8574_ADDRESS_2 = ( 0x22 << 1 ), PCF8574_ADDRESS_3 = ( 0x23 << 1 ),
  PCF8574_ADDRESS_4 = ( 0x24 << 1 ), PCF8574_ADDRESS_5 = ( 0x25 << 1 ), PCF8574_ADDRESS_6 = ( 0x26 << 1 ), PCF8574_ADDRESS_7 = ( 0x27 << 1 ),
  PCF8574A_ADDRESS_0 = ( 0x38 << 1 ), PCF8574A_ADDRESS_1 = ( 0x39 << 1 ), PCF8574A_ADDRESS_2 = ( 0x3A << 1 ), PCF8574A_ADDRESS_3 = ( 0x3B << 1 ),
  PCF8574A_ADDRESS_4 = ( 0x3C << 1 ), PCF8574A_ADDRESS_5 = ( 0x3D << 1 ), PCF8574A_ADDRESS_6 = ( 0x3E << 1 ), PCF8574A_ADDRESS_7 = ( 0x3F << 1 )
}
 

DEFAULT ADDRESSES.

More...
enum  PCF8574_pin_number_t {
  PCF8574_P0 = 0, PCF8574_P1 = 1, PCF8574_P2 = 2, PCF8574_P3 = 3,
  PCF8574_P4 = 4, PCF8574_P5 = 5, PCF8574_P6 = 6, PCF8574_P7 = 7
}
 

PIN NUMBER.

More...
enum  PCF8574_pin_mask_t {
  PCF8574_P0_MASK = 0b00000001, PCF8574_P1_MASK = 0b00000010, PCF8574_P2_MASK = 0b00000100, PCF8574_P3_MASK = 0b00001000,
  PCF8574_P4_MASK = 0b00010000, PCF8574_P5_MASK = 0b00100000, PCF8574_P6_MASK = 0b01000000, PCF8574_P7_MASK = 0b10000000
}
 

PIN MASK.

More...
enum  PCF8574_pin_configuration_t {
  PCF8574_P0_INPUT = ( 1 << PCF8574_P0 ), PCF8574_P0_OUTPUT_HIGH = ( 1 << PCF8574_P0 ), PCF8574_P0_OUTPUT_LOW = ( 0 << PCF8574_P0 ), PCF8574_P1_INPUT = ( 1 << PCF8574_P1 ),
  PCF8574_P1_OUTPUT_HIGH = ( 1 << PCF8574_P1 ), PCF8574_P1_OUTPUT_LOW = ( 0 << PCF8574_P1 ), PCF8574_P2_INPUT = ( 1 << PCF8574_P2 ), PCF8574_P2_OUTPUT_HIGH = ( 1 << PCF8574_P2 ),
  PCF8574_P2_OUTPUT_LOW = ( 0 << PCF8574_P2 ), PCF8574_P3_INPUT = ( 1 << PCF8574_P3 ), PCF8574_P3_OUTPUT_HIGH = ( 1 << PCF8574_P3 ), PCF8574_P3_OUTPUT_LOW = ( 0 << PCF8574_P3 ),
  PCF8574_P4_INPUT = ( 1 << PCF8574_P4 ), PCF8574_P4_OUTPUT_HIGH = ( 1 << PCF8574_P4 ), PCF8574_P4_OUTPUT_LOW = ( 0 << PCF8574_P4 ), PCF8574_P5_INPUT = ( 1 << PCF8574_P5 ),
  PCF8574_P5_OUTPUT_HIGH = ( 1 << PCF8574_P5 ), PCF8574_P5_OUTPUT_LOW = ( 0 << PCF8574_P5 ), PCF8574_P6_INPUT = ( 1 << PCF8574_P6 ), PCF8574_P6_OUTPUT_HIGH = ( 1 << PCF8574_P6 ),
  PCF8574_P6_OUTPUT_LOW = ( 0 << PCF8574_P6 ), PCF8574_P7_INPUT = ( 1 << PCF8574_P7 ), PCF8574_P7_OUTPUT_HIGH = ( 1 << PCF8574_P7 ), PCF8574_P7_OUTPUT_LOW = ( 0 << PCF8574_P7 )
}
 

PIN CONFIGURATION.

More...
enum  PCF8574_pin_status_t {
  PCF8574_P0_HIGH = ( 1 << PCF8574_P0 ), PCF8574_P0_LOW = ( 0 << PCF8574_P0 ), PCF8574_P1_HIGH = ( 1 << PCF8574_P1 ), PCF8574_P1_LOW = ( 0 << PCF8574_P1 ),
  PCF8574_P2_HIGH = ( 1 << PCF8574_P2 ), PCF8574_P2_LOW = ( 0 << PCF8574_P2 ), PCF8574_P3_HIGH = ( 1 << PCF8574_P3 ), PCF8574_P3_LOW = ( 0 << PCF8574_P3 ),
  PCF8574_P4_HIGH = ( 1 << PCF8574_P4 ), PCF8574_P4_LOW = ( 0 << PCF8574_P4 ), PCF8574_P5_HIGH = ( 1 << PCF8574_P5 ), PCF8574_P5_LOW = ( 0 << PCF8574_P5 ),
  PCF8574_P6_HIGH = ( 1 << PCF8574_P6 ), PCF8574_P6_LOW = ( 0 << PCF8574_P6 ), PCF8574_P7_HIGH = ( 1 << PCF8574_P7 ), PCF8574_P7_LOW = ( 0 << PCF8574_P7 )
}
 

PIN STATUS.

More...
enum  PCF8574_status_t { , I2C_SUCCESS = 0 }
 

INTERNAL CONSTANTS.

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Public Member Functions

 PCF8574 (PinName sda, PinName scl, uint32_t addr, uint32_t freq)
 Create an PCF8574 object connected to the specified I2C pins.
 ~PCF8574 ()
 Delete PCF8574 object.
PCF8574_status_t PCF8574_SetPins (PCF8574_vector_data_t myConfDATA)
 It configures and sets the pins of the device.
PCF8574_status_t PCF8574_ReadPins (PCF8574_vector_data_t *myReadDATA)
 It reads the state of the pins of the device.

Detailed Description

Example:

include "mbed.h" include "PCF8574.h"

PCF8574 myDevice ( I2C_SDA, I2C_SCL, PCF8574::PCF8574_ADDRESS_0, 400000 );

Ticker newReading; DigitalOut myled1 ( LED1 ); DigitalOut myled2 ( LED2 ); InterruptIn myPCF8574INT ( p8 );

PCF8574::PCF8574_status_t aux; uint32_t mySTATE = 0;

void flip ( void ) { PCF8574::PCF8574_vector_data_t myData;

Read the port to check P7 status aux = myDevice.PCF8574_ReadPins ( &myData );

if ( ( myData.data & PCF8574::PCF8574_P7_MASK ) == PCF8574::PCF8574_P7_MASK ) myled2 = 1; // Turn the LED 2 on when P7 is HIGH else myled2 = 0; // Turn the LED 2 off when P7 is LOW }

void changeDATA ( void ) { PCF8574::PCF8574_vector_data_t myData;

myled1 = 1;

Read the port to mask P7 aux = myDevice.PCF8574_ReadPins ( &myData ); myData.data = ( myData.data & PCF8574::PCF8574_P7_MASK );

Change the state of the PCF8574 pins: P[O-6] if ( mySTATE == 0 ) { myData.data |= ( PCF8574::PCF8574_P0_OUTPUT_LOW | PCF8574::PCF8574_P1_OUTPUT_HIGH | PCF8574::PCF8574_P2_OUTPUT_LOW | PCF8574::PCF8574_P3_OUTPUT_HIGH | PCF8574::PCF8574_P4_OUTPUT_LOW | PCF8574::PCF8574_P5_OUTPUT_HIGH | PCF8574::PCF8574_P6_OUTPUT_LOW );

aux = myDevice.PCF8574_SetPins ( myData );

mySTATE = 1; } else { myData.data |= ( PCF8574::PCF8574_P0_OUTPUT_HIGH | PCF8574::PCF8574_P1_OUTPUT_LOW | PCF8574::PCF8574_P2_OUTPUT_HIGH | PCF8574::PCF8574_P3_OUTPUT_LOW | PCF8574::PCF8574_P4_OUTPUT_HIGH | PCF8574::PCF8574_P5_OUTPUT_LOW | PCF8574::PCF8574_P6_OUTPUT_HIGH );

aux = myDevice.PCF8574_SetPins ( myData );

mySTATE = 0; }

myled1 = 0; }

int main() { PCF8574::PCF8574_vector_data_t myData;

Configure PCF8574: P[0-6] OUTPUTs, P7 INPUT myData.data = ( PCF8574::PCF8574_P0_OUTPUT_LOW | PCF8574::PCF8574_P1_OUTPUT_LOW | PCF8574::PCF8574_P2_OUTPUT_LOW | PCF8574::PCF8574_P3_OUTPUT_LOW | PCF8574::PCF8574_P4_OUTPUT_LOW | PCF8574::PCF8574_P5_OUTPUT_LOW | PCF8574::PCF8574_P6_OUTPUT_LOW | PCF8574::PCF8574_P7_INPUT );

aux = myDevice.PCF8574_SetPins ( myData );

myPCF8574INT.mode( PullUp ); myPCF8574INT.fall( &flip ); // attach the address of the flip function to the falling edge newReading.attach( &changeDATA, 0.5 ); // the address of the function to be attached ( changeDATA ) and the interval ( 0.5s )

Let the callbacks take care of everything while(1) { sleep(); } }

Library for the PCF8574 Remote 8-bit I/O expander for I2C-bus with interrupt.

Definition at line 116 of file PCF8574.h.

Member Enumeration Documentation

enum PCF8574_address_t

DEFAULT ADDRESSES.

NOTE: There are two version: PCF8574 and PCF8574A with different address only, its functionality remains the same.

Enumerator:
PCF8574_ADDRESS_0 

A2 A1 A0: 000

PCF8574_ADDRESS_1 

A2 A1 A0: 001

PCF8574_ADDRESS_2 

A2 A1 A0: 010

PCF8574_ADDRESS_3 

A2 A1 A0: 011

PCF8574_ADDRESS_4 

A2 A1 A0: 100

PCF8574_ADDRESS_5 

A2 A1 A0: 101

PCF8574_ADDRESS_6 

A2 A1 A0: 110

PCF8574_ADDRESS_7 

A2 A1 A0: 111

PCF8574A_ADDRESS_0 

A2 A1 A0: 000

PCF8574A_ADDRESS_1 

A2 A1 A0: 001

PCF8574A_ADDRESS_2 

A2 A1 A0: 010

PCF8574A_ADDRESS_3 

A2 A1 A0: 011

PCF8574A_ADDRESS_4 

A2 A1 A0: 100

PCF8574A_ADDRESS_5 

A2 A1 A0: 101

PCF8574A_ADDRESS_6 

A2 A1 A0: 110

PCF8574A_ADDRESS_7 

A2 A1 A0: 111

Definition at line 123 of file PCF8574.h.

enum PCF8574_pin_configuration_t

PIN CONFIGURATION.

Enumerator:
PCF8574_P0_INPUT 

PCF8574 P0 INPUT

PCF8574_P0_OUTPUT_HIGH 

PCF8574 P0 OUTPUT HIGH

PCF8574_P0_OUTPUT_LOW 

PCF8574 P0 OUTPUT LOW

PCF8574_P1_INPUT 

PCF8574 P1 INPUT

PCF8574_P1_OUTPUT_HIGH 

PCF8574 P1 OUTPUT HIGH

PCF8574_P1_OUTPUT_LOW 

PCF8574 P1 OUTPUT LOW

PCF8574_P2_INPUT 

PCF8574 P2 INPUT

PCF8574_P2_OUTPUT_HIGH 

PCF8574 P2 OUTPUT HIGH

PCF8574_P2_OUTPUT_LOW 

PCF8574 P2 OUTPUT LOW

PCF8574_P3_INPUT 

PCF8574 P3 INPUT

PCF8574_P3_OUTPUT_HIGH 

PCF8574 P3 OUTPUT HIGH

PCF8574_P3_OUTPUT_LOW 

PCF8574 P3 OUTPUT LOW

PCF8574_P4_INPUT 

PCF8574 P4 INPUT

PCF8574_P4_OUTPUT_HIGH 

PCF8574 P4 OUTPUT HIGH

PCF8574_P4_OUTPUT_LOW 

PCF8574 P4 OUTPUT LOW

PCF8574_P5_INPUT 

PCF8574 P5 INPUT

PCF8574_P5_OUTPUT_HIGH 

PCF8574 P5 OUTPUT HIGH

PCF8574_P5_OUTPUT_LOW 

PCF8574 P5 OUTPUT LOW

PCF8574_P6_INPUT 

PCF8574 P6 INPUT

PCF8574_P6_OUTPUT_HIGH 

PCF8574 P6 OUTPUT HIGH

PCF8574_P6_OUTPUT_LOW 

PCF8574 P6 OUTPUT LOW

PCF8574_P7_INPUT 

PCF8574 P7 INPUT

PCF8574_P7_OUTPUT_HIGH 

PCF8574 P7 OUTPUT HIGH

PCF8574_P7_OUTPUT_LOW 

PCF8574 P7 OUTPUT LOW

Definition at line 179 of file PCF8574.h.

enum PCF8574_pin_mask_t

PIN MASK.

Enumerator:
PCF8574_P0_MASK 

PCF8574 P0 INPUT

PCF8574_P1_MASK 

PCF8574 P1 INPUT

PCF8574_P2_MASK 

PCF8574 P2 INPUT

PCF8574_P3_MASK 

PCF8574 P3 INPUT

PCF8574_P4_MASK 

PCF8574 P4 INPUT

PCF8574_P5_MASK 

PCF8574 P5 INPUT

PCF8574_P6_MASK 

PCF8574 P6 INPUT

PCF8574_P7_MASK 

PCF8574 P7 INPUT

Definition at line 163 of file PCF8574.h.

enum PCF8574_pin_number_t

PIN NUMBER.

Enumerator:
PCF8574_P0 

PCF8574 P0 INPUT

PCF8574_P1 

PCF8574 P1 INPUT

PCF8574_P2 

PCF8574 P2 INPUT

PCF8574_P3 

PCF8574 P3 INPUT

PCF8574_P4 

PCF8574 P4 INPUT

PCF8574_P5 

PCF8574 P5 INPUT

PCF8574_P6 

PCF8574 P6 INPUT

PCF8574_P7 

PCF8574 P7 INPUT

Definition at line 148 of file PCF8574.h.

enum PCF8574_pin_status_t

PIN STATUS.

Enumerator:
PCF8574_P0_HIGH 

PCF8574 P0 STATUS HIGH

PCF8574_P0_LOW 

PCF8574 P0 STATUS LOW

PCF8574_P1_HIGH 

PCF8574 P1 STATUS HIGH

PCF8574_P1_LOW 

PCF8574 P1 STATUS LOW

PCF8574_P2_HIGH 

PCF8574 P2 STATUS HIGH

PCF8574_P2_LOW 

PCF8574 P2 STATUS LOW

PCF8574_P3_HIGH 

PCF8574 P3 STATUS HIGH

PCF8574_P3_LOW 

PCF8574 P3 STATUS LOW

PCF8574_P4_HIGH 

PCF8574 P4 STATUS HIGH

PCF8574_P4_LOW 

PCF8574 P4 STATUS LOW

PCF8574_P5_HIGH 

PCF8574 P5 STATUS HIGH

PCF8574_P5_LOW 

PCF8574 P5 STATUS LOW

PCF8574_P6_HIGH 

PCF8574 P6 STATUS HIGH

PCF8574_P6_LOW 

PCF8574 P6 STATUS LOW

PCF8574_P7_HIGH 

PCF8574 P7 STATUS HIGH

PCF8574_P7_LOW 

PCF8574 P7 STATUS LOW

Definition at line 218 of file PCF8574.h.

enum PCF8574_status_t

INTERNAL CONSTANTS.

Enumerator:
I2C_SUCCESS 

I2C communication was fine

Definition at line 261 of file PCF8574.h.

Constructor & Destructor Documentation

PCF8574 ( PinName  sda,
PinName  scl,
uint32_t  addr,
uint32_t  freq 
)

Create an PCF8574 object connected to the specified I2C pins.

PCF8574.h.

Parameters:
sdaI2C data pin
sclI2C clock pin
addrI2C slave address
freqI2C frequency in Hz.

Remote 8-bit I/O expander for I2C-bus with interrupt. Functions file.

Returns:
NA
Author:
Manuel Caballero
Date:
11/October/2017
Version:
11/October/2017 The ORIGIN
Precondition:
NaN.
Warning:
NaN
Precondition:
This code belongs to AqueronteBlog ( http://unbarquero.blogspot.com ).

Definition at line 20 of file PCF8574.cpp.

~PCF8574 (  )

Delete PCF8574 object.

Definition at line 28 of file PCF8574.cpp.

Member Function Documentation

PCF8574::PCF8574_status_t PCF8574_ReadPins ( PCF8574_vector_data_t *  myReadDATA )

It reads the state of the pins of the device.

PCF8574_ReadPins ( PCF8574_vector_data_t* )

It gets the data from the device ( port status ).

Parameters:
[in]NaN.
[out]myReadDATA,:ADC result into the chosen channel.
Returns:
Status of PCF8574_ReadPins.
Author:
Manuel Caballero
Date:
11/October/2017
Version:
11/October/2017 The ORIGIN
Precondition:
NaN
Warning:
NaN.

Definition at line 89 of file PCF8574.cpp.

PCF8574::PCF8574_status_t PCF8574_SetPins ( PCF8574_vector_data_t  myConfDATA )

It configures and sets the pins of the device.

PCF8574_SetPins ( PCF8574_vector_data_t )

It configures/sets the pins of the device.

Parameters:
[in]myConfDATA,:Data to set up the device.
[out]NaN.
Returns:
Status of PCF8574_SetPins.
Author:
Manuel Caballero
Date:
11/October/2017
Version:
11/October/2017 The ORIGIN
Precondition:
NaN
Warning:
NaN.

Definition at line 53 of file PCF8574.cpp.

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