Low memory Read All not working

[iuliux]

I copied from an example and I get this:

ledWemos:51: error: cannot convert 'PCF8574::DigitalInput' to 'byte {aka unsigned char}' in initialization
   byte d = pcf8574.digitalReadAll();
                                   ^
exit status 1
cannot convert 'PCF8574::DigitalInput' to 'byte {aka unsigned char}' in initialization

I defined PCF8574_LOW_MEMORY too, this is the full code, run on a Wemos D1 Mini (esp8266):

/*
 * PCF8574 GPIO Port Expand
 * http://nopnop2002.webcrow.jp/WeMos/WeMos-25.html
 *
 * PCF8574    ----- WeMos
 * A0         ----- GRD
 * A1         ----- GRD
 * A2         ----- GRD
 * VSS        ----- GRD
 * VDD        ----- 5V/3.3V
 * SDA        ----- GPIO_4(PullUp)
 * SCL        ----- GPIO_5(PullUp)
 *
 * P0     ----------------- LED0
 * P1     ----------------- LED1
 * P2     ----------------- LED2
 * P3     ----------------- LED3
 * P4     ----------------- LED4
 * P5     ----------------- LED5
 * P6     ----------------- LED6
 * P7     ----------------- LED7
 *
 */

#include "Arduino.h"
#include "PCF8574.h"  // https://github.com/xreef/PCF8574_library

#define PCF8574_LOW_MEMORY

// Set i2c address
PCF8574 pcf8574(0x20);

void setup()
{
  Serial.begin(115200);
  delay(1000);

  for(int i=0;i<8;i++) {
    pcf8574.pinMode(i, INPUT);
  }
	Serial.print("Init pcf8574...");
	if (pcf8574.begin()){
		Serial.println("OK");
	} else {
		Serial.println("KO");
	}
}

void loop() {
  byte d = pcf8574.digitalReadAll();
  Serial.print("READ VALUE FROM PCF: ");
  Serial.println(d, BIN);
//  Serial.println(di);
  delay(1000);
}

[xreef]

Hi,
you must uncomment the line inside PCF8574.h at this line
https://github.com/xreef/PCF8574_library/blob/master/PCF8574.h#L53

Bye Renzo

[iuliux]

If you didn't have to modify the library would be better, but works.
Thank you for the library.

[xreef]

Try to set the define before include of the library