ODC 2800 contains a set of five modulatable Effects to supplement the emulation of the Odyssey. In order to make these effects' user interfaces large enough to be comfortable to work with, ODC 2800 makes use of this little button, found at the bottom left corner of the instrument window:
When this button is set to KEYBOARD, the familiar Keyboard View is displayed:
This includes controls for the Arpeggiator and Aftertouch modulation, to the left and right of the keys.
Note that even in Keyboard View, some controls for the Effects are accessible under the keys.
Setting the button to EFFECTS brings up the Effects View:
This supplements the controls under the keyboard with detailed parameters for each of the five Effects processors.