Fieldbus

2020-02-28T01:19:23.065000Z

In a mixed application with Ethercat and Modbus masters, you see an influence on Modbus update to Ethercat task / sending frames- How could this be avoided?

You need a proper seperation of the use of the modbus io's and ethercat io's according to the task which does the buscycle update:

Set Ethercat master in 'PLC Settings' as' Buscycle Task' - and Ethercat io's are only used in ethercat task context (in that case in PLC_PRG)
specify on Modbus master the update task for Modbus - and Modbus io's are only used in Modbus task context ( in that case in ModbusPRG)
Check if these rules are ok with 'task deployment' tap - Rule: Ethercat io's are only updated in the Ethercat task - Modbus io's are only updated on the Modbus task context - this you see with the red cross on each used io.
check online help for 'bus cycle'

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Fieldbus

2020-02-28T01:19:18.081000Z

Question:
How to reset the Master in IEC:

Answer:
Do not use auto restart option and IEC code at the same time.
Use a rising trigger to reset the Master with xReset.

      Ethercat_Master.xRestart := xReset;
      Ethercat_Master();

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Fieldbus

2020-02-28T01:19:15.981000Z

But we can’t locate the actual Boolean Trigger variable?

You can find the trigger var, if you change the Trigger to “Rising edge” :

you can define any bool var and map the var like any other in/output within the IOMapping for this channel.

What is the scope of the trigger boolean?
Yes
Will it cause just one channel to be written?
Yes

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Fieldbus

2020-02-28T01:19:10.807000Z

Question:
EtherCAT Error detection in IEC
Answer:
Master:
Diagnostics Message can be read within the Master configuration tab.
Same in EtherCAT_Master.m_sLastMesage

Slave:
Slave State can be read within the Slave configuration tab. Diagnostics Current State
Same with  SlaveName.wState (call of the slave instance is required)
Example:

```

EK1100(); // Name of the slave = "EK1100"
   EL1004();
   EL2008();
   IF NOT EK1100.wState = ETC_SLAVE_STATE.ETC_SLAVE_OPERATIONAL THEN
   // do something
   END_IF

**Snippet:**Snippet:


A very good example is the ethercat example in the CODESYS store: [http://store.codesys.com/ethercat-example.html#Support](http://store.codesys.com/ethercat-example.html#Support)

( Get some information of the slaves and master. It is possible to go through all masters and slaves
and get information about them. )
( EtherCAT_Master is an instance of the IoDrvEtherCAT function block.)
( The number of active slaves )
uiActiveSlaves := EtherCAT_Master.NumberActiveSlaves;
( Get the ETCMaster )
pEtcMasterFB := EtherCAT_Master.Master;
( The number of SDO's )
iSDOCnt := pEtcMasterFB^.GetNumberOfSDO;
( Go through all Slaves )
pSlave := Ethercat_Master.FirstSlave;
WHILE pSlave <> 0 DO
( get the address of the current slave. This can also be found under the device in the "Slave" tab. )
uiSlaveAddr := pSlave^.SlaveAddr;

pSlave^();
( Get the state of the slave )
( With pSlave^.SetOpMode(ETC_SLAVE_STATE), the state can be set.)
IF pSlave^.wState = ETC_SLAVE_STATE.ETC_SLAVE_OPERATIONAL THEN
;
END_IF

pSlave := pSlave^.NextInstance;
END_WHILE

```

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Fieldbus

2020-02-28T01:19:09.012000Z

EtherCat revocering from disconnection

Question:
Which steps are needed to recover from disconnected slaves

Answer:
There are two use cases:
1. IEC application should care on restart / error handling
xRestart on Master is needed
2. restart of slaves is done automatically:
The EtherCAT Master provides an option to restart the fieldbus:
Master Configuration, Master: Checkbox: Auto restart slaves
3. Optional Slaves are possible (this is a tag 'Optional') in the slave config

Fieldbus

2020-02-28T01:19:03.958000Z

Fieldbus related:

EtherCat recovering from disconnection
EtherCat, How to reset the Master in IEC?
EtherCat, Error detection in IEC
EtherCat project contains additional Modbus TCP Master: update of Ethercat frames seems to be influenced by modbus update - how could this be avoided?
Modbus, Trigger variable

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