BECKHOFF EL9xxx - Manual (Page 78)

Appendix
Solution
Go step­by­step from the original state to the desired state.
7.4.5 Error Code 0x0012
Meaning
Unknown requested state change
Description
The ESM defines the following states. They are coded with fixed values (only lower (=right) nibble):
BOOT: AL Control = 0x03
INIT: AL Control = 0x01
PREOP: AL Control = 0x02
SAFEOP: AL Control = 0x04
OP: AL Control = 0x08
The fifth bit of the AL Control (left nibble is 1) is the “Error Acknowledge Bit”. If the slave is in AL STATUS =
0x14, i.e. ERROR SAFEOP the master acknowledges this by setting the Acknowledge bit.
Example: If any other value for AL Control than those specified are sent.
Current State (or state change)
Any
Resulting state
Current State + E
Solution
Do only request the defined states
7.4.6 Error Code 0x0013
Meaning
Boot state not supported
Description
Device does not support BOOT state, but the master requests the slave to go to BOOT (AL Control = 0x03
Current State (or state change)
I→B
Resulting state
I + E
EL9xxx 78 Version 3.1