Asus Eee Pad Transformer Prime TF201 Using Manual page 2

2. Ensure your Transformer has the minimum battery power as indicated
on the screen. We recommend you to connect the power adapter to your
Transformer before firmware update. Tap OK to continue.
To start firmware update immediately, tap Install.
3.
Or you can assign a time for later update and tap Postpone.
4. Your Transformer will restart to complete firmware update. To confirm
the update result, check the Build number by tapping Apps menu >
Settings > About tablet.

ASUS Transformer