Different channels map are ignored

[RobertoDF]

Hi,

Yesterday we did a test recording selecting different channels configuration on our neuropixel (PXI) probe and we realized that the probe viewer doesn´t get updated when different channels are enabled.
In the image you can see that I selected the channels at the base of the shank however in the probe viewer we still access only the channels at the tip. Is there a way to select different channels in probe viewer? Thanks!

[medengineer]

To clarify terminology, there are 384 channels and 960 electrodes to select from on each probe.

The Probe Viewer displays all 384 channels, independent of which electrode is actually connected to that channel. There is currently no option to select channels nor electrodes via Probe Viewer. We are planning to add a feature such that the data displayed in Probe Viewer is organized by depth of the electrode in the brain.

[RobertoDF]

Ok that makes sense with what we were seeing during the exp. I have another question (not sure this is the right place though): is information about which electrode is associated to which channel saved somewhere in the binaries with OpenEphys?

[medengineer]

Whenever you save your signal chain, the current electrode configuration for each probe is saved in the lastConfig.xml file that lives in the same directory as open-ephys.exe. You can search on the 'CHANNELSTATUS' tag in that file to find a map of electrode numbers to status values, where 0 = disconnected, 1 = connected. For each connected electrode, the corresponding channel is the electrode number mod 384.