When additional messages/alarms occur, the first seven are kept in the HMI, and the latestmessage or the latest alarm is displaced from one that has just occurred according to thefollowing rules:● System message/alarm displaces user message/alarm● Messages/alarms with a higher priority displace those of a lower priority.The first seven messages/alarms are kept in the display because it is very probable that thesedefine the cause of the problem and the following are just of a secondary nature. However, ifone or several messages/alarms are acknowledged and therefore cleared, then acorresponding number of alarms/messages that have been received move up in the HMI.14.6.4 PLC axis control14.6.4.1 OverviewTargetThe PLC can control eight axes or spindles via data blocks of the user interface; the axis/spindleis specified by its DB number:● DB380x PLC → NCK interface● DB390x NCK → PLC interface● DB390x Axis index: 0 ≤ x ≤ 7, whereby axis index = axis number-1The following functions are supported:● Positioning axes● Spindle positioning● Rotate spindle● Oscillate spindle● Indexing axesReferences:● Function Manual, Extended Functions; Positioning Axes (P2) and Indexing axes (T1)● Function Manual, Basic Functions; Spindles (S1)PreconditionThe axis to be controlled must be assigned to the PLC. An axis can be interchanged betweenNC and PLC using the user interface "Axis interchange" (DB3800.DBB8/DB3900.DBB8).P4: PLC for SINUMERIK 828D14.6 Function interfaceBasic FunctionsFunction Manual, 01/2015, 6FC5397-0BP40-5BA2 1123