Skip to content

Commit

Permalink
For enhancement #5.
Browse files Browse the repository at this point in the history 
Add variable to prevent use of complex structure and free 7 byte of mem.
  • Loading branch information
@mwreef
mwreef committed Jun 2, 2018
1 parent 4bec9ba commit 114c3ca
Show file tree
Hide file tree
Showing 3 changed files with 147 additions and 52 deletions.
122 changes: 81 additions & 41 deletions PCF8574.cpp
View file
Original file line number Diff line number Diff line change
Expand Up @@ -149,50 +149,90 @@ void PCF8574::readBuffer(bool force){
}
}

/**
* Read value of all INPUT pin
* Debounce read more fast than 10millis, non managed for interrupt mode
* @return
*/
PCF8574::DigitalInput PCF8574::digitalReadAll(void){
DEBUG_PRINTLN("Read from buffer");
Wire.requestFrom(_address,(uint8_t)1);// Begin transmission to PCF8574 with the buttons
lastReadMillis = millis();
if(Wire.available()) // If bytes are available to be recieved
{
DEBUG_PRINTLN("Data ready");
byte iInput = Wire.read();// Read a byte

if ((iInput & readMode)>0){
DEBUG_PRINT("Input ");
DEBUG_PRINTLN((byte)iInput, BIN);

byteBuffered = byteBuffered | (byte)iInput;
DEBUG_PRINT("byteBuffered ");
DEBUG_PRINTLN(byteBuffered, BIN);
}
}
#ifndef PCF8574_LOW_MEMORY
/**
* Read value of all INPUT pin
* Debounce read more fast than 10millis, non managed for interrupt mode
* @return
*/
PCF8574::DigitalInput PCF8574::digitalReadAll(void){
DEBUG_PRINTLN("Read from buffer");
Wire.requestFrom(_address,(uint8_t)1);// Begin transmission to PCF8574 with the buttons
lastReadMillis = millis();
if(Wire.available()) // If bytes are available to be recieved
{
DEBUG_PRINTLN("Data ready");
byte iInput = Wire.read();// Read a byte

DEBUG_PRINT("Buffer value ");
DEBUG_PRINTLN(byteBuffered, BIN);
if ((iInput & readMode)>0){
DEBUG_PRINT("Input ");
DEBUG_PRINTLN((byte)iInput, BIN);

if ((bit(0) & readMode)>0) digitalInput.p0 = ((byteBuffered & bit(0))>0)?HIGH:LOW;
if ((bit(1) & readMode)>0) digitalInput.p1 = ((byteBuffered & bit(1))>0)?HIGH:LOW;
if ((bit(2) & readMode)>0) digitalInput.p2 = ((byteBuffered & bit(2))>0)?HIGH:LOW;
if ((bit(3) & readMode)>0) digitalInput.p3 = ((byteBuffered & bit(3))>0)?HIGH:LOW;
if ((bit(4) & readMode)>0) digitalInput.p4 = ((byteBuffered & bit(4))>0)?HIGH:LOW;
if ((bit(5) & readMode)>0) digitalInput.p5 = ((byteBuffered & bit(5))>0)?HIGH:LOW;
if ((bit(6) & readMode)>0) digitalInput.p6 = ((byteBuffered & bit(6))>0)?HIGH:LOW;
if ((bit(7) & readMode)>0) digitalInput.p7 = ((byteBuffered & bit(7))>0)?HIGH:LOW;

if ((readMode & byteBuffered)>0){
byteBuffered = ~readMode & byteBuffered;
DEBUG_PRINT("Buffer hight value readed set readed ");
byteBuffered = byteBuffered | (byte)iInput;
DEBUG_PRINT("byteBuffered ");
DEBUG_PRINTLN(byteBuffered, BIN);
}
}

DEBUG_PRINT("Buffer value ");
DEBUG_PRINTLN(byteBuffered, BIN);
}
DEBUG_PRINT("Return value ");
return digitalInput;
};

if ((bit(0) & readMode)>0) digitalInput.p0 = ((byteBuffered & bit(0))>0)?HIGH:LOW;
if ((bit(1) & readMode)>0) digitalInput.p1 = ((byteBuffered & bit(1))>0)?HIGH:LOW;
if ((bit(2) & readMode)>0) digitalInput.p2 = ((byteBuffered & bit(2))>0)?HIGH:LOW;
if ((bit(3) & readMode)>0) digitalInput.p3 = ((byteBuffered & bit(3))>0)?HIGH:LOW;
if ((bit(4) & readMode)>0) digitalInput.p4 = ((byteBuffered & bit(4))>0)?HIGH:LOW;
if ((bit(5) & readMode)>0) digitalInput.p5 = ((byteBuffered & bit(5))>0)?HIGH:LOW;
if ((bit(6) & readMode)>0) digitalInput.p6 = ((byteBuffered & bit(6))>0)?HIGH:LOW;
if ((bit(7) & readMode)>0) digitalInput.p7 = ((byteBuffered & bit(7))>0)?HIGH:LOW;

if ((readMode & byteBuffered)>0){
byteBuffered = ~readMode & byteBuffered;
DEBUG_PRINT("Buffer hight value readed set readed ");
DEBUG_PRINTLN(byteBuffered, BIN);
}
DEBUG_PRINT("Return value ");
return digitalInput;
};
#else
/**
* Read value of all INPUT pin in byte format for low memory usage
* Debounce read more fast than 10millis, non managed for interrupt mode
* @return
*/
byte PCF8574::digitalReadAll(void){
DEBUG_PRINTLN("Read from buffer");
Wire.requestFrom(_address,(uint8_t)1);// Begin transmission to PCF8574 with the buttons
lastReadMillis = millis();
if(Wire.available()) // If bytes are available to be recieved
{
DEBUG_PRINTLN("Data ready");
byte iInput = Wire.read();// Read a byte

if ((iInput & readMode)>0){
DEBUG_PRINT("Input ");
DEBUG_PRINTLN((byte)iInput, BIN);

byteBuffered = byteBuffered | (byte)iInput;
DEBUG_PRINT("byteBuffered ");
DEBUG_PRINTLN(byteBuffered, BIN);
}
}

DEBUG_PRINT("Buffer value ");
DEBUG_PRINTLN(byteBuffered, BIN);

byte byteRead = byteBuffered;

if ((readMode & byteBuffered)>0){
byteBuffered = ~readMode & byteBuffered;
DEBUG_PRINT("Buffer hight value readed set readed ");
DEBUG_PRINTLN(byteBuffered, BIN);
}
DEBUG_PRINT("Return value ");
return byteRead;
};
#endif

/**
* Read value of specified pin
Expand Down
31 changes: 20 additions & 11 deletions PCF8574.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -18,6 +18,9 @@
// Uncomment to enable printing out nice debug messages.
// #define PCF8574_DEBUG

// Uncomment for low memory usage this prevent use of complex DigitalInput structure and free 7byte of memory
// #define PCF8574_LOW_MEMORY

// Define where debug output will be printed.
#define DEBUG_PRINTER Serial

Expand Down Expand Up @@ -55,16 +58,6 @@

class PCF8574 {
public:
struct DigitalInput {
uint8_t p0;
uint8_t p1;
uint8_t p2;
uint8_t p3;
uint8_t p4;
uint8_t p5;
uint8_t p6;
uint8_t p7;
} digitalInput;

PCF8574(uint8_t address);
PCF8574(uint8_t address, uint8_t sda, uint8_t scl);
Expand All @@ -77,7 +70,23 @@ class PCF8574 {

void readBuffer(bool force = true);
uint8_t digitalRead(uint8_t pin);
DigitalInput digitalReadAll(void);
#ifndef PCF8574_LOW_MEMORY
struct DigitalInput {
uint8_t p0;
uint8_t p1;
uint8_t p2;
uint8_t p3;
uint8_t p4;
uint8_t p5;
uint8_t p6;
uint8_t p7;
} digitalInput;


DigitalInput digitalReadAll(void);
#else
byte digitalReadAll(void);
#endif
void digitalWrite(uint8_t pin, uint8_t value);

private:
Expand Down
46 changes: 46 additions & 0 deletions examples/readAll_Interrupt_lowMemory/readAll_Interrupt_lowMemory.ino
View file
Original file line number Diff line number Diff line change
@@ -0,0 +1,46 @@
#include "Arduino.h"
#include "PCF8574.h"

// To use in low memory mode and prevent use of 7byte you must decomment the line
// #define PCF8574_LOW_MEMORY
// in the library

// For arduino uno only pin 1 and 2 are interrupted
#define ARDUINO_UNO_INTERRUPTED_PIN 2

// Function interrupt
void keyChangedOnPCF8574();

// Set i2c address
PCF8574 pcf8574(0x39, ARDUINO_UNO_INTERRUPTED_PIN, keyChangedOnPCF8574);
unsigned long timeElapsed;
void setup()
{
Serial.begin(115200);

pcf8574.pinMode(P0, INPUT);
pcf8574.pinMode(P1, INPUT);
pcf8574.pinMode(P2, INPUT);
pcf8574.begin();

Serial.println("START");

timeElapsed = millis();
}

bool keyChanged = false;
void loop()
{
if (keyChanged){
byte di = pcf8574.digitalReadAll();
Serial.print("READ VALUE FROM PCF: ");
Serial.println(di, BIN);
// delay(5);
keyChanged= false;
}
}

void keyChangedOnPCF8574(){
// Interrupt called (No Serial no read no wire in this function, and DEBUG disabled on PCF library)
keyChanged = true;
}

0 comments on commit 114c3ca

Please sign in to comment.