Reading frames might return fewer frames than requested

[epage]

This has its roots in the use of NI-XNET's C API. nxReadFrame only accepts number of bytes. It then returns the number of frames that can fit within that byte array (unless its single point, in which case it will error).

Any frames that are 24-bytes will work but anything past that are subject to this bug.

Work around: Call lower level read calls (like read_bytes) and do the post-processing yourself.

[epage]

Ideally, the NI-XNET C API gets a richer nxReadFrame. In the DAQmx C API, you ask for the number of samples separate from specifying the buffer size. If the buffer is too small, it will error. There is also a mode where you can ask the function how big to make the buffer given the number of samples (standard C double call allocation strategy).

[epage]

This could be more critical for Single Point because you have to always ask for the number of frames contained in the session.