I got the ByVac BV4208 working, the library is here.
To use include the library “Wire” and then “ByVacLCD” (I don’t know why you have to include “Wire” even though the library already includes it but you do – I spent ages on this one). Note as this is I2C it uses analog inputs 4 and 5.
#include <Wire .h>
#include <ByVacLCD .h>
// declare the object – address in the data sheet is 0×42 but you
// need to divide this by two to get the ‘normal’ 7 bit I2C address
// – the low order bit is added on by Wire.
// this declaration is for 4 rows of 20 characters.
ByVacLCD bv = ByVacLCD(0×21,4,20);
void setup()
{
bv.init();
bv.print(“Hello World”);
}
void loop()
{
bv.setCursor(1,0);
bv.print(millis());
}
