Canon BJ-230 User Manual page 41

NOTE: When you load letter-wide paper in landscape orientation, the
printer actually prints in portrait mode. So make sure you select
portrait for your printing orientation in the printer driver.
If you select User Defined Size, the Setup program displays the
following dialog box:
First select the unit of measurement you are using (inches or
millimeters), and then specify the width and length of your paper.
T
Click on the arrow next to the Paper Source setting to select one
of the followin paper sources:
Auto Sheet Feeder, which is the default
Manual Feed
NOTE: When using manual feed, make sure the Print Manager is
turned off, in the Printers dialog box.