Beckhoff EL6751 Documentation page 127

Parameterization and commissioning
After a power-on, the EL6751 is in the INIT state and has no CANopen configuration. The CAN controller is
in the OFFLINE state.
CAN Bus parameter / CANopen slave configuration
The configuration stored in the Backup Parameter Storage object 0x10F2 is loaded during the transition from
INIT to PREOP. Since the StartUp SDOs from the Configuration of the EL6751 with StartUp SDOs [} 123] are
stored in the Backup Parameter Storage object, the sequence is the same as the one described there.
Hence, the stored data are first written to object 0xF800 and then the EL6751 switches the CAN controller
with the appropriate baud rate from 0xF800:02 to ONLINE. Subsequently, the CANopen slaves are
generated according to the stored CANopen slave configuration. If the PREOP state is acknowledged, the
current CANopen configuration in objects 0xF800, 0x8yy0, 0x8yy6, 0x8yy8 and 0x8yy3 can be read.
PDO Mapping / PDO Assign
In addition, the EtherCAT master can also read the PDO Mapping and PDO Assign in the PREOP state in
order to determine the lengths of the EtherCAT process data.
Creating the Backup Parameter Storage
The Backup Parameter Storage can be created as follows:
1. Download the object 0x10F2 (in PREOP, SAFEOP or OP): in this case, the data received are stored as
Backup Parameter Storage in the flash memory
2. Scan the CAN bus and then write the value 0x65766173 to entry 0x1010:01: here, the EL6751
automatically generates the Backup Parameter Storage from the InfoData 0x9yy0, 0x9yy8 and 0x9yyA and
stores it in the flash memory.
In both cases the EL6751 is automatically rebooted after 5 s (reverts to INIT with the AL status code 0x60).
Furthermore, all SDO downloads of the objects 0xF800 or 0x8yyz are rejected.
Deleting the Backup Parameter Storage
In order to load a new Backup Parameter Storage or to simply delete the existing one, the value
0x64616F6C has to be written to entry 0x1011:01.
5.5.1.2 Synchronization
In the EL 6751, the CAN cycle is synchronized with the EtherCAT cycle. Synchronization takes place by
default via the Sync Manager 2 event or, if there is no EtherCAT output process data, via the Sync Manager
3 event. Alternatively, the EL6751 can also be operated in the Distributed Clocks mode, in which case
synchronization takes place via the SNYC0 and SYNC1 events.
CAN cycle (Sync Multiplier = 1)
The following flow chart shows the sequence of the CAN cycle if a CAN cycle is also executed with each
EtherCAT cycle (Sync Multiplier = 1 (0x1C32:02 == 0xF800:04 or 0x1C32:02 == 0 (default) or 0xF800:04 ==
0)). If the cycle time of the EtherCAT master (0x1C32:05) is not transmitted in the StartUp SDOs (or the
Backup Parameter Storage object) and no Distributed Clocks mode is set, then 0x1C32:05 = 0 and, hence,
the Sync Multiplier = 1.
EL6751 Version: 3.5 127