My setup is as follows:
- Arduino IDE 1.6.11
- Arduino Pro Mini as ISP
- ATTiny85 1602A LCD with I2C board
The libraries I use are:
- TinyWireM (source: https://github.com/adafruit/TinyWireM)
- LiquidCrystal_I2C (modified for ATTiny) (source: http://playground.arduino.cc/Code/USIi2c)
The Sketch I use to test with:
#include <TinyWireM.h>
#include <LiquidCrystal_I2C.h>
LiquidCrystal_I2C lcd(0x3F,16,2); // set address & 16 chars / 2 lines
void setup()
{
TinyWireM.begin(); // initialize I2C lib
lcd.init(); // initialize the lcd
lcd.backlight();
lcd.clear(); // Print a message to the LCD.
}
void loop()
{
lcd.setCursor(0, 0);
lcd.print("Hello World on Attiny85");
delay(2000);
}
The address is 0x3F, I found this using the scanner sketch, I also tested the LCD using the Arduino Pro Mini directly, it works fine.
The result of this setup is a single line of black blocks. My guess is that the initialization failed in some way. I have tried some things to make it work:
- Pull-ups on SDA and SCL
- Isolated from Arduino with regulated power supply
- Setting contract with the pot meter on the back
- reinstall of PC
- reinstall of Arduino IDE
- 1MHz, 8Mhz, TinyCore default and High-Low Tech
- Replaced FTDI
- Replaced Tiny85
- Replaced LCD
- Replaced Arduino Pro Mini
Some pictures:
[EDIT]
Final sketch:
#include <TinyWireM.h> // I2C Master lib for ATTinys which use USI
// #include <LiquidCrystal_I2C.h>
#include "LiquidCrystal_attiny.h"
LiquidCrystal_I2C lcd(0x27,16,2);
void setup() {
// Now set up the LCD
//lcd.begin(16,2); // initialize the lcd
pinMode(4, OUTPUT);
lcd.init();
lcd.backlight();
lcd.home (); // go home
lcd.print("Weatherstation");
lcd.setCursor ( 0, 1 ); // go to position
lcd.print("BMP180");
delay(2000);
}
void loop() {
digitalWrite(4, HIGH);
delay(100);
digitalWrite(4, LOW);
delay(100);
}
