Equipments (Devices) > PLC200 > Program > Communication Network > CANopen

Operation in CANopen Network - Master Mode

NOTE!

The CANopen network is only available on the PLC201 model.

In addition to operating as a slave, the programmable controller PLC201 also allows operation as master of the CANopen network. The characteristics and functions of the PLC201 as a CANopen network master are described below.

Enabling the Master CANopen Function

As default, the programmable controller PLC201 is programmed to operate as slave of the CANopen network. Programming the equipment as a network master must be done using the WSCAN software, which also allows the configuration of the entire CANopen network. A detailed description of the windows and functions of the WSCAN WSCAN software is found in the Help menu Help of the software. WSCAN.

After the master configuration has been created, it is necessary to download the configurations, using one of the interfaces to set the product – see the user manual for further information. Once programmed as network master, if necessary to delete those configurations, the function to delete the user’s program - available in the Setup menu – also erases the configurations of the CANopen master.

NOTE!

The CANopen network is a flexible network that allows several forms of configuration and operation. However, in order to use this flexibility, it is necessary that the user know well both the communication functions and objects used to configure the network, as well as the WSCAN WSCAN programming software.

Characteristics of the CANopen Master

The programmable controller PLC200 allows controlling a group of up to 63 slaves, using the following communication services and resources:

•	Network manager task (NMT)

•	63 transmission PDOs

•	63 PDOs of receives

•	63 Heartbeat Consumers

•	Heartbeat Producer

•	SDO Client

•	SYNC producer/consumer

•	512 bytes of incoming network markers (input)

•	512 bytes of outgoing network markers (output)

The physical characteristics—installation, connector, cable, etc.—are the same for the PLC200 operating as both master and slave. The configurations of address and baud rate are also necessary to operate as master, but these configurations are programmed by the WSCAN WSCAN software according to the properties defined for the master in the software itself. WSCAN.

NOTE!

Incoming network markers are used to map data in RPDOs, while the outgoing network markers are used to map data in TPDOs. They can be accessed in Byte (%IB or %QB), Word (%IW or %QW) or Double Word (%ID or %QD). Its function, however, is not pre-defined and depends on the Ladder application developed for the controller PLC200.

Operation of the Master

Once programmed to operate as master, the programmable controller PLC200 will execute the following steps for initialization, in a sequence, for each slave:

1.	Send the communication reset command to the entire network, so that the slaves initialize with known values for the communication objects.

2.	Identification of the equipment in network, through the reading via SDO of the object 1000h/00h – Object Identification.

3.	Writing via SDO of all the objects programmed for the slave, which usually includes the configuration and mapping of the TPDOs and RPDOs, node guarding, heartbeat, besides the specific objects of the manufacturer, in case they are programmed.

4.	Start the error control task – node guarding or heartbeat – if they are programmed.

5.	Send the slave to operating mode.

If one of these steps fails, the communication with slave error will occur. Depending on the settings, the slave initialization will be aborted, and the master will initialize the next slave, returning to the slave with error after trying to initialize all the other network slaves.

Similarly, if, during the operation of a slave, an error is identified in the error control task, depending on the configurations of the master, the slave will be automatically reset and the initialization procedure will be run again.

NOTE!

The communication status and the status of each slave can be observed in input system markers.

Blocks for the CANopen Master

In addition to the communication objects and the configurations made on the WSCAN WSCAN software, blocks for monitoring and sending commands are also available. They can be used during the preparation of the Ladder application for the programmable controller PLC200. It is not necessary to use these blocks during the equipment operation, but they provides more flexibility and simplify the communication troubleshooting during the operation of the programmable controller PLC200.