Triggers - Polycom SoundStructure C16 Design Manual

Design Guide for the Polycom SoundStructure C16, C12, C8, and SR12

Triggers

Actions
9 - 2
Digital logic inputs held
(digital_gpio_held)
IR keypress (ir_key_press)
IR key held (ir_key_held)
The trigger determines when the information in the source becomes action-
able. Triggers may be one of three values: always, equals, or range as defined
below.
• The always trigger means that any changes to the source parameter will
cause the action to execute.
• The equals trigger means that when the source parameter equals the
desired value (e.g., open or closed for logic inputs), the action will execute.
• The range trigger means that anytime the source parameter value is equal
to or greater than the min value and less than or equal to the max value,
the action will execute.
Triggers are 'edge' triggered, meaning that when the source parameter value
changes, the event engine will determine whether the trigger condition is met
or not. For example, for logic input switches this means there are two edges –
when a logic input is closed (has a value of 0), or when a logic input is opened
(has a value of 1). The following figure shows the two signal edges associated
with a button press – the transition from open to closed and from closed to
open. Either edge, or both edges, may be used to trigger events.
Switch Open
1
Logic State
0
The action specifies what happens when the trigger condition is met. Actions
include
Digital logic inputs (digital_gpio_state)
Analog logic input values
(digital_gpio_value)
Switch Closed
Push Release
Switch Open