Stange characters with I2C display: normal printing to screen works, but not the custom characters

[BRB2000]

As the title already says, I do have a problem with a HD44780 in combination with a PCF8574AT. I have downloaded the new LiquidCrystal library, and everything works, including setting my own custom characters, but as soon as I want to use any Big method (eg. writeBig), it just displays weired characters on the screen. It works fine in 4Bit mode though.

Thank you in advance,
Richard.B.

[wmarkow]

BigCrystal works fine for me when I have used the old LiquidCrystal library with 4 bit mode. But I started to have similar problems (like any Big method was not working) when I switched the library to new-LiquidCrystal and a hardware interface to I2C. I didn't set my own custom characters but when I used any Big method then I had some weired characters on the LCD. After some time I have figured out that I need to call a BigCrystal::begin method; calling LCD::begin (from new-LiquidCrystal library) is not enough. Maybe it will work for you:

#include <Wire.h>
#include <LiquidCrystal_I2C.h> // this comes from new-LiquidCrystal library
#include <BigCrystal.h>

LiquidCrystal_I2C lcd(0x27, 2, 1, 0, 4, 5, 6, 7); // this works fine for my 20x4 LCD and I2C PCF8574AT module
BigCrystal bigLcd(&lcd); // this will create a big crystal object

void setup()
{
  // lcd.begin(20, 4);  // this is not enough to make BigCrystal working
  bigLcd.begin(20, 4); // this is a correct way to configure BigCrystal (it will install big font as a custom characters and will call the LCD::begin() as well)
}