Super micro sas826a backplane

Just wondering if anyone knows which SAS connectors on the SAS826A backplane control which ports?

On my current setup only ports 8-11 are working so got some troubleshooting ahead of me.

The online manuals show the connectors but unhelpfullyndont indicate which ports are being used for each.

Also, anyone know what the ribbon cable beside the SAS wires is used for on supermicro cables? I don’t recall seeing it on other SAS cables.