BECKHOFF EtherCAT Technology Section I - Manual (Page 30)

EtherCAT Protocol
I-10 Slave Controller – Technology
Table 6: EtherCAT Command Types
CMD Abbr. Name Description
0 NOP No Operation Slave ignores command
1 APRD Auto Increment Read Slave increments address. Slave puts read data
into the EtherCAT datagram if received address is
zero.
2 APWR Auto Increment Write Slave increments address. Slave writes data into
memory location if received address is zero.
3 APRW Auto Increment Read Write Slave increments address. Slave puts read data
into the EtherCAT datagram and writes the data
into the same memory location if received address
is zero.
4 FPRD Configured Address Read Slave puts read data into the EtherCAT datagram
if address matches with one of its configured
addresses
5 FPWR Configured Address Write Slave writes data into memory location if address
matches with one of its configured addresses
6 FPRW Configured Address Read
Write Slave puts read data into the EtherCAT datagram
and writes data into the same memory location if
address matches with one of its configured
addresses
7 BRD Broadcast Read All slaves put logical OR of data of the memory
area and data of the EtherCAT datagram into the
EtherCAT datagram. All slaves increment position
field.
8 BWR Broadcast Write All slaves write data into memory location. All
slaves increment position field.
9 BRW Broadcast Read Write All slaves put logical OR of data of the memory
area and data of the EtherCAT datagram into the
EtherCAT datagram, and write data into memory
location. BRW is typically not used. All slaves
increment position field.
10 LRD Logical Memory Read Slave puts read data into the EtherCAT datagram
if received address matches with one of the
configured FMMU areas for reading.
11 LWR Logical Memory Write Slaves writes data to into memory location if
received address matches with one of the
configured FMMU areas for writing.
12 LRW Logical Memory Read Write Slave puts read data into the EtherCAT datagram
if received address matches with one of the
configured FMMU areas for reading. Slaves writes
data to into memory location if received address
matches with one of the configured FMMU areas
for writing.
13 ARMW Auto Increment Read
Multiple Write
Slave increments address. Slave puts read data
into the EtherCAT datagram if received address is
zero, otherwise slave writes the data into memory
location.
14 FRMW Configured Read Multiple
Write
Slave puts read data into the EtherCAT datagram
if address matches with one of its configured
addresses, otherwise slave writes the data into
memory location.
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