Store DTI to SD card

[ORSO2001]

Dear All,

 

I have to store a DTI table, when it is full (1000 rows and 8 columns), in the SD card...and after I have to clear the table to start again with the recording of the data...how much time is needed to store compleately the table to enable the "clear DTI" ladder function?

in the "help" I found an extimated time only if I use this function followed by a "load from file" function.

 

thanks

[Sam_ry]

i do it in real time. every time i save something in the DTI, in writing also in the CSV

 

show the image on in the attachement

 

hope it was useful. 

[ORSO2001]

Dear Sam_ry,

 

thanks for your answer; in the next days I will test it (my function).

[Saragani]

Hi, reading or writing rows from/to data table is immediate.

Storing or loading data to data table from a file takes time. You should better look at the status of the Store DTI (it will change to "In Progress", which I think is 1). The status will change to 0 upon success, or to an error code if there was a problem.

 

You should not clear the data in the table before the store was completed.

[ORSO2001]

Dear Saragani,

 

yes, I have seen that the DTI store "give" an output status as 0,1,-1...and I have used it to know if the action is done or not...but I need to know, more or less, how much time will be needed because it will put in "pause" the checking of the external devices...I calculate that a complete check of all external device will needs 9 sec...if the store action will need 15 sec, during which the check will put in pause, will be lost 2 checking cycles and it is too much for me...otherwise I have to create a second DTI and switch the saving when one is in store mode....

Thanks

[Saragani]

The time it takes to save the table to a file depends on its total size, and also on the internal SD Card itself (different cards have different performance).

If the Panel is busy, it may increase the time even more, and if the SD Card is being read or written by something else, then it would also increase the time.

(for example, an online/debug process during the time you try to save, especially when viewing Data Tables, or even Data Table Widgets on HMI and Web Server will also slow down the process)

 

The max size of a retained table is 262,124 Bytes. I've made some test on how much time it takes to save such a table, and it took 1.5 seconds

(The test application doesn't do anything else).

 

I also created a non retained table with the size of 2,000,000 Bytes. The save took 5 seconds.

 

 

 

It looks like 9 seconds should be more than enough if your table is not huge.

[ORSO2001]

Dear Saragani,

 

Thanks...It is clear.

[Gugulanov]

Hi,

Just for info, it's not connected directly with the topic, but is connected with saving of table into file.
If I'm not wrong, my observation is, that when if there is a saved DT file once, if you meanwhile change the table struct, and try to save (in my case with overwright), status of "Store DTI to file" function  gives error code.

Deleting the old file helps, and further saves are OK.

It's not a big issue, but someone may wonder what's hapening.

 

Regards.
 

[Saragani]

Hi Gugulanov, this is by design.

(Data Table structure signature is being checked when data is written to the file, on either append or overwrite).

 

 

I will raise this issue for you again.