Defines should all be in UPPERCASE and ensure you check your SPELLINGS of them, as they may not flag errors in any compilation...

http://www.picbasic.co.uk/forum/showthread.php?t=558

I2CREAD and I2CWRITE are really easy to fly with no issues providing you follow the rules in the PICBasic manual...

http://www.picbasic.co.uk/forum/showthread.php?t=587

Please do check the FAQ's...