RedLion Comms Failure

Hi,
I am setting up a AB SLC to G3 communications using the Data Block method.
To my dismay if I unplug the ethernet port it appears that the data from the PLC is still valid whereas if I address the AB data table directly on communication failure the data points go to "----"
Is there an easy way to make the Data Block show the comms has failed.

Thanks

Roy

All my G3 apps have an alarm called STATUS_COMMS using Complex code:


where x is the device number.

You could use that as part of the data block expression to conditionally show whatever you want in place of the value.

You could use that as part of your data block to condition the displayed value. I have not used datablocks, so I don't know the slickest method to do this.

Another much easier thing to try is to remove any value you have in the Simulate As: field for any of the source tags for the datablock. Just a hunch.

My G3s respond instantly to comms losses which is nice, and they recover in seconds too, although serial seems to recover much faster than ethernet when I test the comms failure action. I did have one issue caused by a rogue switch on our network that sent a G3 into a repetitive reboot cycle, but a quick power cycle fixed that issue in under ten seconds...so much better than PC based crapware...

Thanks Okie,
I will try that out on Monday
Regards

Roy

OkiePC,

The code IsDeviceOnline (x), is that in just one discrete "flag" that you connect to all other communication tags or the graphics ie to show "####" when the comms is down
Is (x) the name of the PLC ie should my code read
IsDeviceOnline (PLC1), the default.
Sorry to be such a pain, I'm an old dog, and you know what they say.

The device number "x" is found by looking at the Communications settings for the device. When highlighted, the device number will appear at the top of the center window.

If PLC1 is device 3, then your expression should read "return IsDeviceOnline(3);"

I normally use it in the definition of a flag tag, and set the alarm trigger for that tag to "level triggered", and "active off". I have not used it as part of an expression in a data block. I have not used data blocks at all.

OkiePC said:

The device number "x" is found by looking at the Communications settings for the device. When highlighted, the device number will appear at the top of the center window.

If PLC1 is device 3, then your expression should read "return IsDeviceOnline(3);"

I normally use it in the definition of a flag tag, and set the alarm trigger for that tag to "level triggered", and "active off". I have not used it as part of an expression in a data block. I have not used data blocks at all.

Click to expand...

If you are using Crimson 3.0 you can also use this syntax:

IsDeviceOnline(PLC1). Just replace PLC1 with the name of your device.

Thank you gentlemen for the jump start, I have tested out several different options using this code, i'm sure I can get it to do what I need

Just an update
I will use the complex code in the "Show" tab. The tag dissapears so I will paste it over the top of text "****", that seems to work
As I said before tags directly addressed show as "----" when the communications goes down.
Thanks again guys
Roy