HP E1433A User's Guide

The C-Language Host Interface Library

Group IDs

Group IDs are logical IDs which are created by a call to

e1432_create_channel_group. This function can be called multiple times to create multiple groups, and each group can contain any combination of channels, including mixtures of different types of channels. The channel groups can overlap as well.

This function creates and initializes a channel group. A channel group allows you to issue commands to several HP E1433A channels at once, simplifying system setup. The state of an individual HP E1433A 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.

If successful, this function returns the ID of the group that was created, which is then used to reference the channel group in most other functions in this library. A group ID is always negative.

As a side effect, this function makes all input channels in the channel group active, and all source and tach channels in the channel group inactive. Unlike the HP 1431A library, this function does not inactivate other channels within the modules that the channels are in. Also unlike the HP 1431A library, this function does not preset the channels in the new group.

As an example, to create a group consisting of the first three input channels and the eighth and ninth input channels, the code would like something like this:

SHORTSIZ16 chan_list[5]; SHORTSIZ16 input_group; chan_list[0] = E1432_INPUT_CHAN(1); chan_list[1] = E1432_INPUT_CHAN(2); chan_list[2] = E1432_INPUT_CHAN(3); chan_list[3] = E1432_INPUT_CHAN(8); chan_list[4] = E1432_INPUT_CHAN(9);

input_group = e1432_create_channel_group(hw, 5, chan_list);

To create a group consisting of the first two source channels, the code would look something like this:

SHORTSIZ16 chan_list[2]; SHORTSIZ16 source_group; chan_list[0] = E1432_SOURCE_CHAN(1); chan_list[1] = E1432_SOURCE_CHAN(2);

source_group = e1432_create_channel_group(hw, 2, chan_list);

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HP 8-Channel 196 kSa/sec Digitizer plus DSP E1433A manual Group IDs