Beckhoff EtherCAT EL6001, Документация

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Commissioning
EL600x, EL602x 127 Version: 4.6
Optimization of transfer rates
In normal operating mode the data received will be adopted immediately into the process image. In order to
enable a continuous flow of data, the ‘Enable transfer rate optimization’ option in the Settings object is
activated as standard. Due to this switch, the data will first be stored intermediately in the receive buffer
(864 bytes).
The data will only be copied into the process image if no further character is received for 16 bit periods or if
the buffer is full.
Continuous transmission of data
Usually the EL60xx terminal automatically decides when to send the data bytes contained in the buffer. For
many applications it is helpful to have a continuous data stream. For this purpose, the Beckhoff EL60xx
terminals feature the ‘Enable send FIFO data continuous’ setting in the Settings object. If this switch is set.
• The internal send buffer (128 bytes) must be filled first. To this end, data will be sent from the controller
to the terminal as in a normal data transfer.
• Data transfer from the buffer commences with a rising edge of the bit “Send continuous”
• If the data has been transferred, the terminal informs the controller by setting the “InitAccepted” bit. “Init
accepted” is cleared with “Send continuous”.
This setting enables up to 128 bytes to be transferred without long delays, even with slower EtherCAT cycle
times and high baud rates.
The terminal tries to leave as little distance as possible between the telegrams by seamlessly following each
stop bit with the next start bit. Nevertheless, in two-channel mode high baud rates may result in short pauses
between telegrams. A 20-byte data block may be sent in two blocks of 5 and 15 or 7 and 13 telegrams, for
example, or with a different distribution. In a two-channel terminal channel 1 is given priority.
Prioritization
Since received data normally cannot be repeated, it has a higher priority than data to be transmitted.
Furthermore, the priority decreases as the channel number increases. Hence, the reception of data on
channel 1 has the highest priority.
Command mode
From firmware 06 / revision -0018 the EL6021 supports the so-called command mode. Certain terminal
functions can be used and controlled through optional combination and/or sequence of commands. The
following functions are currently supported:
• Multi-data frame feature: (from firmware 06) change of coding during ongoing data communication
(sending)
To this end the send buffer of the terminal should be filled with the bytes to be sent (note the maximum
buffer size). As soon as the send process is started via the control word, the first n bytes are sent
based on coding A, the remaining bytes in the buffer are sent with coding B. The buffer can then be
refilled and sent accordingly. Example: The first byte is sent with mark parity, the remaining bytes with
space parity.
Sequence:
◦ After each startup/restart of the EL60xx EtherCAT slave the parameterization has to be repeated.
The command function is not stored in the event of a power failure.
◦ Activation of SendContinuous mode through writing of 0x1 after 0x8000:04
◦ Activation of the multi-data frame feature through writing of 0x2001 after request 0xB000:01
Check that 0xB000:02 = 0
◦ Specify coding A through writing of [date frame code] after 0xB000:01
Example: 8E2 = 0x12 --> write value 0x2112
Check that 0xB000:02 = 0
◦ Specify n bytes to be sent in coding A through writing of [n] after 0xB000:01
Check that 0xB000:02 = 0
◦ Specify coding B through writing of [date frame code] after 0xB000:01
Check that 0xB000:02 = 0