IFM ecomat 100 R 360 Series, Системное руководство

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PDO mapping A conventional PDO mapping is not possible in the ecomat
R 360 since this is not necessary for a plc.
Via the application program the data relevant to the CANopen
network can be directly written into the PDOs or read from them.
Network variables in the area from %MW 2000 for the received
data and from %MW 2032 for the data to be transmitted can be
immediately processed by the application program (see
appendix 1.5). Thus 8 x 4 transmission words (TX-PDOs) and
8 x 4 reception words (RX-PDOs) are available to the user.
Monitoring the PDO reception The detection whether new data have been transferred is not
supported by CANopen. If this function is required, it must be
created by the programmer. This can be done as follows:
•
Write the signature in the receive object
•
PDO contains a toggle bit or consecutive number
•
Use the function block CAN_RECEIVE
Transmission types The transmission types SYNC, i.e. synchronous transmission
after a PDO SYNC object or ASYNC, i.e. transmission after a
change of the network variables (event due to a change) are
supported. The COB ID of the sync object can be configured.
The indication of an inhibit time can delay the sending of
ASYNC objects. So considerably fluctuating process values can
cause an extremely high bus load in the case of an event-
controlled evaluation. If the inhibit time is indicated, the next
PDO cannot be sent to the bus before the time has elapsed.
If strategically important values are to be transferred in the
ASYNC mode, a single transmission may not be safe enough.
Via the function block PDO_TX_REFRESH the important PDO
can be repeated from time to time.
As default setting all PDOs are transmitted after a data change
(ASYNC mode).
Node guarding If an ecomat R 360 is accessed by the NMT master once by
means of a guarding object, it is fully controlled by the
NMT master by means of the cyclical node guarding. If the CAN
communication is disturbed, a guarding error message is
created in the NMT master. Also, in the R 360 CANopen slave
the flag COP_EVENT_GUARDFAIL is set.
The programmer must evaluate these error messages in his
software, specially for critical applications.