Starting up CANopen fieldbus nodes

3.1.7 Starting up CANopen fieldbus nodes

This chapter shows the step-by-step procedure for starting up a

WAGO CANopen fieldbus node.

Attention

This description is given as an example and is limited to the execution of a local start-up of an individual CANopen fieldbus node

The procedure contains the following steps:

1.Connecting the PC and Fieldbus Node

2.Checking and setting the Baud rate

3.Setting the Module ID

4.Changing to the OPERATIONAL Status

5.Turning on the Analog Input Data

6.Application specific Mapping

3.1.7.1Connecting the PC and fieldbus node

Connect the CANopen fieldbus node to the CANopen fieldbus PCB in your PC by means of a fieldbus cable and start the PC.

3.1.7.2 Checking and setting the Baud rate

First of all turn all DIP switches to the “OFF” position (module ID = 0), then switch on the voltage supply (DC 24 V power pack) at the fieldbus controller.

1 ON

2

3

4

5

6

7

8

Now the currently set Baud rate is checked and displayed in the top LED group by the blinking of the corresponding LED’s.

Note

If switching on the voltage, when all DIP switches have not been pushed to “OFF”, the existing setting is adopted as the module ID.

Now push the corresponding DIP switches for the desired Baud rate to 'ON', i.e. for the Baud rate 125 kB to DIP switch 3.

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1 ON

2

4

5

6

7

8

To store the new setting, push the DIP switch 8 also to 'ON'.

Then switch the supply voltage of the controller off.

1 ON

2

4

5

6

7

3.1.7.3 Setting the module ID

The module ID is set with the supply voltage switched off. For this purpose, push all DIP switches temporarily to the “OFF” position. Then push the corresponding DIP switches for the desired module ID to “ON”, i.e. DIP switch 1 for the module ID 1.

Now as soon as the supply voltage is switched on, the controller is in the INITIALIZATION mode.

At the same time, the process image is created on the basis of the connected bus modules, and the object directory is initialized according to the default mapping, if no application specific configuration was stored.

Following an error free completion of the initialization phase, the controller automatically changes to the PRE-OPERATIONAL status.

In this status, the communication via SDOs is possible. You can now proceed with various settings via your CAN master software:

•You can set the coupler directly to the OPERATIONAL setting.

Note

Due to the fact that in the default setting the PDO transmission of the analog input data is switched off, the analog input data is not taken into account.

•You can turn off the deactivated transmission of analog input data or

•select an application specific mapping.

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3.1.7.4 Changing to the OPERATIONAL status

The command Start_Remote_Node from the network management objects permits you to change the controller status from PRE-OPERATIONAL to OPERATIONAL. This establishes the communication readiness of the fieldbus node for PDOs (refer to chapter 5.3.3.1.1 "Start Remote Node").

Note

In the default setting, the PDO transmission of the analog input data is switched off. For this reason, this data is read out only once and not updated again. To allow this data to be used via PDOs, the analog input data in the PRE-OPERATIONAL status have to be turned on. In this manner, access via the SDOs is possible at any time.

If no further settings are performed, the controller is operational and communication possible in accordance with the default mapping (refer to chapter

5.3.4.1"Initialization").

3.1.7.5Turning on the analog input data

To prevent the CAN bus from being flooded with CAN messages, the transmission of analog input data via PDOs is deactivated in the default setting. This means that the object 0x6423 "Analoge Input Global Interrupt Enable" is assigned with the default value 'FALSE' (= '0') (refer to chapter 5.3.4.4.12

"Object 0x6423, Analog Input Global Interrupt Enable").

If the controller is in the PRE-OPERATIONAL status, you can enable the transmission in general by changing the object 0x6423 to the value TRUE (= '1').

Subsequently you can use the "Start Remote Node" command to change the controller PRE-OPERATIONAL status to the OPERATIONAL status. In this manner both communication via the PDOs and the transmission of analog input data are possible.

If no further settings are made, the controller is operational and communication can occur according to the default mapping (refer to chapter 5.3.4.1

"Initialization").

3.1.7.6 Application specific mapping

An alternative to the use of the default mapping is to define the data to be transmitted by PDOs in an application specific PDO mapping. For this purpose, the coupler has to be in the PRE-OPERATIONAL status.

Details of how to proceed with application specific mapping are explained as follows.

Example:

The 3rd and the 5th 2 byte analog input channel and the first 8 bit digital input group are to be read using the TxPDO 2. For transmission purposes, the CAN identifier 0x432 is to be used. Transmission must be synchronous with each 3rd SYNC object.

The default CAN IDs are used for the SDOs. The setting is made at node 8.

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xx... is not evaluated

1.First of all, deactivate the PDO mapping by zeroing the number of mapping objects in index 0x1A01, sub-index 0 (Transmit PDO Mapping Parameter).

Deactivating PDO mapping:

2.Enter into the TxPDO mapping parameter structure (Index 0x1A01) the Index, Sub-Index and the Object length of the application object.

Max. 8 bytes of data can be assigned per PDO.

Writing into the mapping parameter structure:

3.The following structure must be reached in the mapping parameters of the 2nd TxPDO in order to acknowledge the task set:

TxPDO Mapping Parameter Structure, Index 0x1A01

Note

First of all, enter the mapping parameter sub-index 1 ... 8 in sub-index 0, followed by the number of valid sub-indexes.

These objects are stored with the aid of SDO transmissions:

Mapping 3. analog input channel

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4.Now deactivate the PDO you wish to map for changing the communication parameters.

In the present example, this is the TxPDO2.

To this effect, write value 0x80000000 into the object having the index 0x1801, sub-index 01 (Transmit PDO Communication Parameter).

Deactivating PDO:

5.Write into the object with Index 0x1801, Sub-Index 1 to 3 (Transmit PDO Communication Parameter) the communication parameters in the structure.

Thereby the Transmission Type is 3 ( Synchronous transmission with every 3. SYNC object).

Enter the Communication Parameter:

TxPDO Communication Parameter, Index 0x1801

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100• Fieldbus Controller 750-837, /02x-000, 750-838, /02x-000 Starting up CANopen fieldbus nodes

Sub-Index 3: Inhibit Time = 0

Sub-Index 1: Change COB-ID = 432 on PDO and PDO from invalid to valid

6.When you change the fieldbus controller to OPERATIONAL using the „Start Remote Node" message, the PDOs are activated and the TxPDO object can now be used for data transmission.

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