The schematic diagram (see below) shows PXI-2503 in the 1-Wire 48x1 topology. The SPDT switch labeled as "H/L SEL" used to switch between channels 0-23 (positive side ) and channels 24-47 (negative side of 0-23). Channels can be selected in LabVIEW by sending commands using the NI-Switch virtual instrument driver as shown below.
Selecting (closing) channel 23 in LabVIEW
H/L SEL opens whenever any channel from 0-23 is selected and closes whenever any channel from 24-47 is selected.
The NI manual seems to imply the the switch can be controlled by name.
from 2503 manual appendix D
I've tried sending commands to open or close H/L SEL directly but can't get them to work. I also tried the commands "H/LSEL", "HL SEL", and "HLSEL" but those failed as well.
Is there a command to control this switch directly? If so, what is it?