AMO SCSU and AMO
SBCSU subdivides the stations into COS switchover groups (COSX groups). This is performed in order to group stations so that a certain COS can be switched active for all of them.
If no specific allocation has been made, a station belongs to COSX group 00. Stations with an active key switch (KEYSTN) are not changed over, but they are still assigned to a COSX group.
The COSX groups are independent of other station groups formed on the basis of other features.