Below are a few KnowledgeBases that should give you the information to make NI-DAQmx calls from Delphi:
How Can I Use The NI-DAQmx ANSI C Function Library With Borland C and Delphi?
http://digital.ni.com/public.nsf/allkb/B09727F89DA3A06C86256F430071D88E
Can I Make NI-DAQmx Calls From Borland Delphi?
http://digital.ni.com/public.nsf/allkb/A6715AA42405ACD786256F0A00633B8F
Currently only LV, CVI, VB, and C/C++ are supported directly by the driver NI-DMM. But c can make use of the DLL directly in Delphi to make calls to the functions of the DLL
Refer to this link: