16f688 LCD what have I done wrong

[spitfiredriver]

I have removed the crystal but still get nothing on the display, I have not got a datasheet for the LCD just the pinout, hope to be sent the pdf tomorrow. As it has a HD44780 compatible controller and a standard pinout I hoped it would be a positive V0 for contrast but that might be the problem. The only markings on the display are the pinout and (ELECTROLITE QY-162A)

[mackrackit]

Like Tim asked, can you see anything on the display? You may want to look at the PBP manual to see how to use a pot with the contrast pin.

And I will ask. Can you make an LED blink at the correct rate? Maybe the PIC is not even running?

If the PIC is running at the correct speed and you can change the contrast it could be in the commandus or dataus settings.

[Archangel]

As it has a HD44780 compatible controller and a standard pinout I hoped it would be a positive V0 for contrast but that might be the problem. The only markings on the display are the pinout and (ELECTROLITE QY-162A)

Most HD44780 LCD units, pin 3 contrast is at or very near ground, I usually just ground pins 1,3,5

[spitfiredriver]

Thanks for the help
I have solved it, I could not see anything on the display, I knew the program was running as I put an extra led that flashed on each loop.
My mistake was that the display pdf that I was working to, said to wire the back light on pins A and K with a 10 ohm resister. This was wrong, I needed to use pins 15 and 16, there are extra resistors in the circuit. The back light was just too bright. Works fine now.
once again thanks for the advice.