Logic Channels Tab

Overview

The Logic Channels Tab provides configuration of logic (conditional) channels in the display.

The output from a Logic Channel is either zero or one.

Logic Channels may be used to implement alarms. An output of one indicates that the alarm has been triggered (the condition is true), zero indicates no alarm has been triggered (the condition is false).

Conditions

Each row of the grid defines a logical operation that will return true (1) or false (0). When evaluating the alarm output, the display combines the result of the current line and carries it forward to the next line. Lines can be added or removed with the Add or Delete buttons.

In the above example, the logic channel will output 1 if “Bat Alarm > 0” OR ‘Coolant Alarm > 0’.

The channel can be renamed using the Channel Name box.

Delay Before Trigger

The Delay Before Trigger value adds a delay after display power on before the alarm is processed. This is useful when using logic channels for triggering page changes as it can be used to prevent erroneous page triggers when ECUs broadcast default values whilst initialising.

Retrigger After

The Retrigger After value specifies a timeout in seconds after which the alarm (if still triggered) will toggle to un-triggered and back to triggered. This is useful for when an logic channel has been used to trigger a page change, usually showing a warning to the driver, for example, low oil pressure. The driver can select the standard page again to cancel the alarm. If the oil pressure is still low after the specified period, then the warning page will be shown again.

If the Retrigger value is set to zero, then the alarm will only retrigger if the input conditions change to false and back to true again.