SpikeGLX is loading `XD` channels both as events and signal

[h-mayorquin]

from neo.rawio import SpikeGLXRawIO
from pathlib import Path

folder_path = Path("/home/heberto/neuroconv_testing_data/ephy_testing_data/spikeglx/DigitalChannelTest_g0")
rawio = SpikeGLXRawIO(folder_path)
rawio.parse_header()
rawio

This is the digital only example on the gin tests:

So for SpikeGLX the XD digital channels (non-mux digital channel) is used to form a memmap and then extract every bit as a line:

https://github.com/NeuralEnsemble/python-neo/blob/ab821e727a4081fa7e8ace0e0aa79591f67096a4/neo/rawio/spikeglxrawio.py#L341-L365

But it seems that we are also loading the whole channel in the signal.

I think this is OK and probably desired but I wanted to bring your attention that we are providing two ways of accessing the data here in case the discussion comes for another similar case.