IMC CANSAS - Virtual Channels; What Are Virtual Channels; Creating Virtual Channels

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What are virtual channels? 129

Virtual Channels

4.1 What are virtual channels?

The imc CANSAS-module comes with a fixed number of physical channels whose signals can be

transmitted along the CAN-bus. However, additional, so-called virtual channels can be generated. These

can be data streams computed from a physical channel's signal (e.g. the low-pass filtering of a physical

channel). But virtual channels can also be completely artificial constructions (e.g. a sawtooth signal). Also,

virtual channels can be used to achieve data compression.

Virtual channels are generally used to pre-process imc CANSAS-module data. For instance, passing huge

amounts of data coming into imc CANSAS at a high sampling rate straight into the CANbus would severely

strain its capacities. The data can be pre-processed while still in the imc CANSAS system (e.g. in the form

of averaging, filtering and subsequent data compression). Consequently, the data load transferred to the

CAN-bus can be reduced; only such data are sent to the CAN-bus as are necessary for evaluation

purposes.

4.2 Creating virtual channels

To establish a virtual channel, use the command 'New/ Virtual channel' in the 'Edit' menu or click on

the corresponding tool.

A new virtual channel is created. This virtual channel's entry in the Module Tree appears under 'Without

CAN-bus message'. If the virtual channel is to be transferred on the CAN-bus, it must be assigned to a

message.

When a virtual channel is generated using the imc CANSAS operating software, it initially has default

settings. There are different dialogs providing the ability to make settings for the virtual channel which

are appropriate to your requirements. To do this, select the virtual channel's entry in the Module Tree.

Clicking on one of the filecard tabs makes the desired dialog appear in the foreground.

General notes

This filecard contains the controls for the most basic parameters of a virtual channel. These are its name,

comments, and Y-unit. The virtual channel's sampling rate is additionally displayed since it can differ from

that of its parameter channels owing to the possibilities for data compression.

Other manuals for IMC CANSAS