Updating controller firmware *.efw
![]()  | CoE directory The Online CoE directory is managed by the controller and stored in a dedicated EEPROM, which is generally not changed during a firmware update.  | 
Switch to the Online tab to update the controller firmware of a slave, see Fig. Firmware Update.
Fig.146: Firmware UpdateProceed as follows, unless instructed otherwise by Beckhoff support. Valid for TwinCAT 2 and 3 as EtherCAT master.
- Switch TwinCAT system to ConfigMode/FreeRun with cycle time >= 1 ms (default in ConfigMode is 4 ms). A FW-Update during real time operation is not recommended.
 
 - Switch EtherCAT Master to PreOP

 - Switch slave to INIT (A)
 - Switch slave to BOOTSTRAP
 - Check the current status (B, C)
 - Download the new *efw file (wait until it ends). A password will not be necessary usually.

 - After the download switch to INIT, then PreOP
 - Switch off the slave briefly (don't pull under voltage!)
 - Check within CoE 0x100A, if the FW status was correctly overtaken.
 
