Complete the following steps to locate the PIN and serial number on a BlackBerry PlayBook tablet:
1. From the home screen, tap the settings icon has highlighted below:
2. From the menu on the left, select About.
3. Under the General section, note that the Serial Number is listed.
4. Select the dropdown next to View information about your tablet and choose Hardware.
5. Under the Hardware section, note that the first entry is the PIN.