VXI VT1433B manual Creating a Channel Group, Input, Source and Tach Channels

Models: VT1433B

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Creating a Channel Group

VT1433B User's Guide

Using the VT1433B

Creating a Channel Group

The function hpe1432_createChannelGroup creates and initializes a channel group. A channel group allows commands to be issued to several VT1433B channels at once, simplifying system setup. Channel groups can be overlapped. The state of an individual VT1433B channel that is in more than one channel group is determined by the most recent operation performed on any group to which this channel belongs.

As a side effect, this function makes all input and tach channels in the channel group active and all source channels in the channel group inactive. This function does not inactivate other channels within the modules that the channels are in and does not preset the channels in the new group.

After a channel group has been created, use hpe1432_getGroupInfo to get selected information about the group. It is possible for hpe1432_getGroupInfo to be set up to return the number of modules, channels, inputs, sources or tachs in the group. It can also return a list of the modules, channels, inputs, sources or tachs.

Input, Source and Tach Channels

Channel numbers must fall in particular ranges for different types of channels. Input channel numbers range from 1 to 4095. Source channel numbers range from 4097 to 8191. Tach channel numbers range from 8193 to 12287.

A mixture of input, source and tach channels can be present in one group. However it is also important for many functions to be sent only to the appropriate type of channel. For example, asking for a blocksize from a tach channel can cause an error. It may be useful to set up several channel groups at the beginning of the program: one for input channels, one for source channels, one for tach channels and one that combines all three channel types. The input handle can then be used for input-only functions, the source for source-only functions and the tach handle for tach-only functions. The “all-channels” handle would be used for all other functions.

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VXI manual Creating a Channel Group, Input, Source and Tach Channels, VT1433B Users Guide Using the VT1433B