Display Setup Concepts
Setup Components
A Dash Design setup primarily consists of Channels and Gauges.
Channels are comprised of Sources, Outputs and Sensors, though much of this structure is not separated in the user interface. A CAN signal for example will have a raw ‘source’ that is used for acquiring the channel data and an ‘output’ which is associated with a sensor for scaling the raw data. Logically, the ’type’ of a channel is the associated ‘sensor’ type and the raw source is an implicit input to the ‘output’.
Sources
Non-visual objects that define how data is obtained from an external source such as CAN bus, a digital input or an A/D converter. Sources can be internal to to the display such as CPU temperature.
Channels (Outputs)
Non-visual objects that obtain information from one or more sources or other outputs. An output manipulates the obtained data according to the sensor associated with the output. The result can then be used in a Gauge or another Channel.
Sensors
Non-visual objects that define how the data is manipulated by an output. Examples of sensors are linear scalars, function tables or text tables. Sensors are selected and configured by changing the ’type’ of a Channel.
Gauges
Visual objects that are placed on a screen page. There are two types of gauge; static and dynamic.
Static Gauges
Static Gauges do not change their appearance on the screen and include gauges such as Label Gauge , Shape Gauge or Image Gauge .
Dynamic Gauges
Dynamic (Variable) Gauges change their appearance to reflect data obtained from channels. Examples of variable gauges are Bar Gauges , Tacho Gauges and Value Gauge .
The following diagram shows the relationship between sources, outputs, sensors and gauges:
In this example, the raw RPM value is passed to the scaled RPM output which uses a scalar sensor to provide its’ output. This is passed to both a bar tacho gauge (which displays the RPM) and the oil pressure alarm output. The oil pressure is obtained in a similar manner and passes its’ output to a bar gauge (which displays the oil pressure) and the oil pressure alarm output. The oil pressure alarm output uses the alarm sensor and its’ two inputs to generate an output used by the warning gauge to signal low oil pressure, eg Oil Pressure is less than 2 and engine RPM is greater than 500.