How To Set A Break To Modbus

[dle]

Hi all,

Is there a way to temporarily set a break to all MODBUS channels.

I'm still developing the GUI application and not connecting to a MODBUS device. The alert showing the modbus timeout is so annoying.

 

Thanks.

 

 

[AzeoTech]

Not super easily.  One option is to simply go into safe mode.  Another is to write a script to set the timing of all your channels to 0.  The best way to do this is to put all the channels with a particular timing into a single channel group, then you can do something like:

private string chanList = channel.listAll("modbusReadGroup")
for (private i = 0, i < numrows(chanList), i++)
   execute(chanlist[i] + ".timing = 0")
endfor
channel.restart()

Make another sequence that is pretty much identical but sets the timing to some other value, or just create a sequence function that takes the timing:

function changeTiming(string groupName, newTIming)

private string chanList = channel.listAll(groupName)
for (private i = 0, i < numrows(chanList), i++)
   execute(chanlist[i] + ".timing = " + newTiming)
endfor
channel.restart()

Hardcode groupName like I did in the first example if you don't need it as a parameter.

 

[dle]

Can DF restart a certain channels only ?

 

I tried

channel.restart(chanlist)

or

channel.restart(groupname)

 

but the restart command will initialize all of the channels 

[AzeoTech]

No, restart() recalculates all the timing threads across all the channels.  What are you trying to achieve?

[dle]

I want to disable the modbus channels if the PC id disconnected from a Modbus device.

 

If the function OnAlert() is call, it will check the StrAlert[0].

If the StrAlert[0] = "P-ModbusTCP0010:Timeout", it will temporarily set all the Modbus channels to timing = 0. to stop those Modbus channel from keep trying to polling data.

However, all other channels I would like to keep its current value. 

[AzeoTech]

Your best bet is to not using Timing at all and instead put each device in its own channel Group, then use channel.readGroup() in a sequence to read each device.  Then you can easily add logic to read or not read a device.