Hello Dalu,
In the past, National Instruments only officially supported a few Code Instruments, which are documented in Appendix B of the
GPIB-VXI/C User Manual, but I did not see the VX4240 in the Appendix.
NI officially discontinued support for code instruments on the GPIB-VXI/C about 6 years ago, so you might want to consider moving to a newer VXI controller to access your device. You can find more information on our VXI-MXI-2, VXI-MXI-3, and VXI-1394 remote controller options
here.
Regards,
Joshua Hernstrom
PXI/VXI Product Support Engineer
National Instruments