HD44780 driver to support OLED

I have one of the HD44780 display modules PCB’s and it was connected to a standard 4x20 LCD but I just purchased this module


Connections are the same apart from there is no LED backlight or Vo drive required.

I fired up the Cerbuino with it connected and it does not seem to work too well. Odd characters here and there and one line of the display is showing in reverse on the line above it.

It supports the same 4 bit mode that the module uses.

Looks either like a timing issue or the initialisation of the display is different.

Is the code for the driver freely available for me to try and hack it?