8.4.9 GPI Special Functions
There are five special input functions for which GPIs can be used. There can be no more than one pin assigned to each of these functions.
- GPI Fault Enable - When set, the de-assertion of the GPI is treated as a fault.
- Latched Statuses Clear Source - When a GPO uses a latched status type (_LATCH), a correctly configured GPI clears the latched status.
- Input Source for Margin Enable - When this pin is asserted, all rails with margining enabled will be put in a margined state (low or high).
- Input Source for Margin Low/Not-High - When this pin is asserted all margined rails will be set to Margin Low as long as the Margin Enable is asserted. When this pin is de-asserted the rails will be set to Margin High.
The polarity of GPI pins can be configured to be either Active Low or Active High. The first 3 GPIs that are defined regardless of their main purpose will be used for the PIN_SELECTED_RAIL_STATES command.