Open Source Flight Intrument Documentation [index]
The following requirements apply to stand alone OSFI instruments with either type of LCD display. These requirements are in addition to the generic requirements.
Buttons shall be provided on the instrument to allow the pilot to change user settings and screens in an intuitive manner with a minimal number of button presses.
At a minimum, the following six buttons shall be provided.
| Name | Symbol | Description |
| Up | ^ | Incrementing fields |
| Down | V | Decrementing fields |
| Left | < | Navigating to previous field |
| Right | > | Navigating to next field |
| Page | "Page" | Navigating to next screen |
| Enter | "Enter" | Editing configurable fields |
The size, location and spacing of the buttons shall allow easy operation during flight, even with gloves on the pilot's hands.
A number of screens shall be provided to display flight data and allow changing of user settings. The modes shall display various flight measurements in logical groupings so that data can be rapidly comprehended during flight.
The following measured quantities shall be capable of being represented by the audio signal.