HP E1432A User's Guide

Using the HP E1432A

Creating a Channel Group

The function hpe1432_createChannelGroup creates and initializes a channel group. A channel group allows you to issue commands to several

HP E1432A channels at once, simplifying system setup. You can overlap channel groups. The state of an individual HP E1432A 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 you can use hpe1432_getGroupInfo to get selected information about the group. hpe1432_getGroupInfo can 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.

You can have a mixture of input, source, and tach channels 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. You might find it useful to set up several channel groups at the beginning of your program: one for input channels, one for source channels, one for tach channels, and one that combines all three channel types. You could then use the input handle for input-only functions, the source for source-only functions, and the tach handle for tach-only functions. You would use the “all-channels” handle for all other functions.

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