iphone black screen, voice over on, with passcode lock

If you have passcode on, voice over turned on, and the screen is blacked out.... you cannot see the contents on the screen, and cannot enter your passcode because the voice over is on... don't panic...

plug your iphone to itunes, select phone summary, under "Options" select "Configure Accessibility", then select Seeing "Neither". This will allow you to see the contents of your screen and allow you to type in your passcode.

You may need to reset your phone, by holding down the home and on/off buttons for 30 seconds until the apple icon appears, and then trying the steps above.

good luck.