TIA Portal v18: Saving current date/time to a tag...

[Mas01]

I'm struggling with this...Times and Dates are always a mental-block for me.

See picture.

When I press SAVE, I want to take the current date/time (i.e. "wall clock time/date") and save it in a tag, i.e. it needs to be like a "snapshot" of the time when SAVE was pressed.

Then the next problem is adding 182 days (6 months approx) to that tag and save it in the box below it.

Can anyone point me in the right direction as to how to do this?

Thanks

 

[Mas01]

Hang on, I asked something similar recently...

https://www.plctalk.net/qanda/showthread.php?t=136959

 

[Mas01]

I've managed to add 182 days to a date...that works fine (tick/check)

Problem is, the parameter IN1 is just a 'startup' value I had set up in the DB (by way of experiment).

If I can somehow MOVE the current date/time into IN1 tag (CA_Last_Calibration), I think I'm almost there.

 

[L D[AR2P#0.0]]

Here you go:

 

[Mas01]

Here you go:

Many Thanks for this - but where are #iRetVal, #dtlNow defined?
Are they integers?

 

[L D[AR2P#0.0]]

In the interface of the block. I use the data type to precede the variable name so iRetVal is an integer, dtlNow is of type DTL
Comes in handy when screen shots are posted and you have no idea what data types are being used. I also recommend using
CamelCaseWhereYouSeparateEachWordWithACapitalLetter rather_than_using_underscores.(NB this site introduced the space before the letter r for some reason)

 

[drbitboy]

Many Thanks for this - but where are #iRetVal, #dtlNow defined?
Are they integers?

Since their tags start with a #, they are declared in the local data FC or FB that holds this rung. The are probably Temp variables, although iRetVal could be an additional output parameter from the function (see below) so the caller can determine if there was a problem in the FC.

The TIA Help for the RD_SYS_T instruction documents the data types. #iRetVal will almost certainly be an integer, probably an INT data type; dtlNow will be a DTL data type, because the T_CONV that follows converts DTL data type to Date data type.

​

 

[drbitboy]

CamelCaseWhereYouSeparateEachWordWithACapitalLetter

CamelCaseWhereYouDelimitEachWordWithACapitalLetter

Huh.

 

[Mas01]

Once again, I'm indebted to your replies, chaps.
I didn't even know these functions existed.
I'm back home now but I'll implement it tomorrow.Many thanks.

 

[L D[AR2P#0.0]]

List of instructions available on the RHS

 

[Mas01]

List of instructions available on the RHS

Yes, I knew about the list of instructions in the margin, I was referring to functions, i.e. I didn't know about RD_SYS_T or CONV_T.

 

[Mas01]

I tried implementing the above, but my dtlNow return value is a date from 2012.

I don't understand this.

see picture...

 

[Mas01]

FOR INFO: Here's the tag declarations in "CA_DB":

 

[Guynrush]

Internal PLC system time/date is not correct, probably still with factory default time/date

Set new PLC time date. You can do in two different ways:

1. use function WR_SYS_T

2. Go online with PLC, then select Online & Diagnostics --> Set time --> Apply button

 

[Mas01]

Internal PLC system time/date is not correct, probably still with factory default time/date

Set new PLC time date. You can do in two different ways:

1. use function WR_SYS_T

2. Go online with PLC, then select Online & Diagnostics --> Set time --> Apply button

Superstar! It's working now, cheers.