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Display ON / OFF Instruction

Posted: Fri Mar 23, 2007 11:37 am
by troy.perales
Two Questions:

Is the DISPLAY ON/OFF instruction unecessary for lcds without backlight?

Is there any necessary BUSY FLAG wait between data nibbles when transmitting in 4-bit mode? In other words, do i need to check the BUSY FLAG between the first and second half of the data?

Posted: Fri Mar 23, 2007 12:42 pm
by Ray
Display ON/OFF command on the hd44780 controls the output to the lcd (if your characters are visible or not) and the cusor (visible/invisible/blinking) the hd44780 controller has no control over the backlight at all.

You do not have to check the busy flag in between nibbles only after a complete command has been send.