VXI VT1433B, User Manual, Page: 89 / 203

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
commands to be issued to several VT1433B channels at once, simplifying system
setup. 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.
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
Agilent/HP E1431A library, this function does not inactivate other channels within
the modules that the channels are in. Also unlike the Agilent/HP E1431A 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);
VT1433B User's Guide
The Host Interface Library
4-11