Helmholz CAN 300 PRO, Руководство для стартапов

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7 What Else Is Required …
Now you have the basic function with CAN 300 PRO in
operation, you can extend your application according to your
needs. You can easily add further slaves or adapt the PDO
mapping with the CANParam and test this in the debug tools.
The following sections will explain what else you require...
7.1 I/O area in the PLC
In the I/O area of the CAN 300 PRO, which is located as from
address PIB 256 in our example, you obtain information about
the operating state of the CAN 300 PRO as a CANopen
®
master.
Manual: Section 5 Manual: Section 5
Byte Meaning
PIB 256 Module status generally, CAN group error display
PIB 257 CAN controller status (register of the CAN controller)
PIB 258 FIFO status bits (send & receive)
PIB 259 CAN controller: TX error counter
PIB 260 CAN controller: RX error counter
PIB 261 CANopen
®
: Masterstatus
PIB 262 CANopen
®
: Assignment of the SDO request mailboxes
PIB 263 CANopen
®
: Number of nodes in operational
PIB 264 Node ID on use of the bit filter or of the master
PIB 257, PIB 259, and PIB 260 provide information about the
status of the CAN communication.
In PIB 261, you can see the status of the CANopen
®
master.
In PIB 263, you can see the number of connected CANopen
®
slave
devices that are operational.
You will find more detailed information about these bytes in the
CAN 300 PRO manual in Section 5.
7.2 Monitoring slave devices
As soon as a CANopen
®
slave device is functioning correctly on
the CAN 300 PRO, it is advisable to monitor this device on the
bus for failure. In the previous example, this is not yet done
automatically.
To monitor CANopen
®
slave devices, there are two methods with
CANopen
®
: “Nodeguarding” and “Heartbeat.”
In the case of Nodeguarding , the master monitors the CANopen
®
slave device by cyclically transmitted frames. Each CANopen
®
slave must respond to the nodeguarding frame with a status
frame.
At the same time, the CANopen
®
slave device checks whether it is
regularly receiving frame from the CANopen
®
master to be able to
detect a failure of the master. If the nodeguarding frame of the
Start-up Guide CAN 300 PRO 27