Re: what can be behavior for 3.3v PIC and 5v display
There is a trick worth mentioning but it may not be applicable to that particular PIC:
On devices with 5V tolerant pins, even if running from a 3.3V supply, if the LCD lines are pulled up to 5V using resistors and the PIC ports are driven low, the TRIS registers can be used to safely control the data output. If a pin is set to input mode, the external pull-up will lift it to 5V, if set to output mode, the driver will pull it down to 0V.
Brian.