For those curious, same as the Pen/E-5/XZ-1:
biofos.com: How to access hidden camera codes on most Olympus cameras.
1. With a charged battery installed hold down the MENU button while switching on the camera.
2. When the LCD lights release the MENU button and immediately press it again, once.
3. In the menu go to SPANNER (line 5) and press RIGHT.
4. Press DOWN until you are at the LCD brightness screen (line 3).
5. Enter the brightness screen (shows twin adjusters) by pressing RIGHT and then press INFO and OK sequentially.
6. You will see on the LCD 'OLYMPUS' followed by the designation of your camera (eg E-P1).
7. Press in sequence UP, DOWN, LEFT, RIGHT, SHUTTER and UP for screen 1.
8. You are now in the hidden information screens: RIGHT = screen 2, DOWN = screen 3, LEFT = screen 4.
9. When you have your information simply switch off the camera.
Yikes, was sick the first week I had the camera, but am up to 980 shots (mostly of cats lounging I admit it)