Show last input value on restart

[Jure]

Hello,
is it possible for RP to remember last input value before restart? We are using protocol MQTT where variables are sent only on change. So if we restart RP we won’t get values from PLC until they change.
There is option that we restart PLC so that he will resend all the data or restart MQTT client which sends data, but in the future we could have 20 PLC and clients on different locations and would take a lot of time to restart all of them.

So what we would like is that if “Device” doesn’t have value for input channel after restart, that Scheme displays last known value.

[manjey73]

What is RP ?

[Jure]

Rapid Scada, don’t know why i used RP for abbreviation of Rapid Scada.

• This reply was modified 4 years, 2 months ago by Jure.
• This reply was modified 4 years, 2 months ago by Jure.

[manjey73]

The current data must be saved in the Windows environment. What OS are you using ?

[Mikhail]

Hi,
Try the formula for an input channel:
CnlStat > 0 ? Cnl : Val(); CnlStat > 0 ? CnlStat : Stat()
It should keep the last good value.

• This reply was modified 4 years, 2 months ago by Mikhail.

[Mikhail]

When Rapid SCADA is restarted, Communicator has no tag values and it sends empty data to the server.

[Jure]

It works, thank you. Would maybe be possible to have checkbox for this in some future version instead of formula?

[Mikhail]

A checkbox that does what?

[Jure]

Checkbox for input channel. If it is checked then it automatically uses keeps last good value, without this code.

[Mikhail]

I think, such textbox makes configuration overloaded with options. In the future, it will be possible to make a simple formula included in the software by default.
For example: KeepGoodValue()

[Mikhail]

Currently, it possible to do
KeepGoodVal(); KeepGoodStat()

and add in the Formulas table:

public double KeepGoodVal()
{
  return CnlStat > 0 ? Cnl : Val(); 
}

public int KeepGoodStat()
{
  return CnlStat > 0 ? CnlStat : Stat();
}

[Mikhail]

In version 6 KeepGoodVal() and KeepGoodStat() can be rewritten as a single function that returns a CnlData structure.

[Mikhail]

public CnlData KeepGoodData()
{
  return CnlStat > 0 ? NewData(Cnl, CnlStat) : Data(); 
}

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