I cannot get DAQmxWriteAnalogF64 - a function in NI's COM DLL for the DAQmx library - to work. I have successfully created and started a task and successfully created an analog output channel. However, I am not able to get the DAQmxWriteAnalogF64 to work. No matter what I do, it seems, I continue to get a return code of -200492 which is defined as the error DAQmxErrorCAPIReservedParamNotNULL. I am using a special language named APL implemented by Dyalog.com. It has C typing and COM DLL linking capabilities. I have been able to communicate with the USB-6001 correctly in all the other prerequisite functions. NI's trace function indicates everything is being passed correctly too, but returns that error. I have been told that all that should be necessary is passing a 4 byte unsigned integer with a value of 0 to satisfy the function's requirement for a Null Pointer. NI's documentation for the function specifies this for the 7th parameter required to operate the function:
| reserved | bool32 * | Reserved for future use. Pass NULL to this parameter. |