Write .CSV delimited line to SD

[RickM]

I have a number of identical systems that write a .CSV delimited line to an SD card once a minute. Occasionally one of them will hang, with SB 344 (SD: Write .CSV delimited line to SD in Progress) on and cannot be reset. I have re-initialized the PLC to get SB 344 to reset. What is the best way to reset this bit and what is causing SB 344 to remain on?

Rick M.

[Ofir]

Hi Rick,

Which VisiLogic version are you using?

Please make sure you are using VisiLogic 8.6.1

Which OS version are you using?

Please make sure you are using the latest OS 3.1(19).

Does this bit stucks always on specific system or randomly?

What is the status messages value of the function "Write Delimited Line"?

Please sure also that the max vector you configured in the function "Create Delimeted line" is big enough to hold the vector. (Try to increase the vector lenght)

If you still face the same issue please attach also the applicaiton and steps how to simulate the problem.

[RickM]

Hi Ofir

Using V570, O/S 3.1(05) and VisiLogic 8.6.0 Build 0

I currently have 10 systems running and have seen it happen a month ago on one of the units and two days ago on two other units, unfortunately I did not record which unit it was a month ago. The two units were reset by the customer so I don’t have the status message value of the function. The units are due for a program update so I will increase the vector length at that time.

I can update to VisiLogic 8.6.1, I see in the version change document that the email function GUI has been improved so I will review prior to my program updates as the units are emailing with attachments.

The units are mobile and I connect with a ethernet VPN connection through a cell modem and have not tried an O/S upgrade over the modem, so will test when I have someone at a unit.

We are in the process of commissioning three units and building an additional 45 units so I will make sure they are up to date.

Rick M

[Ofir]

Hi Rick,

Next time it happens, please make sure to get the status messages of this function so we will be able investigate this issue.

Also please note that ejecting the SD and inserting it back also should release this system bit.

[lukeh]

Hi,

I have been having the same issue as described in this post. I have a very simple program that logs the date, time, and a single value into a CSV file and SB 344 gets stuck in the ON position. This doesn't happen every time, but it happens consistently enough to make the program very unreliable. I have checked all of the status messages and they all show no errors (value of 0). I have also checked the length of my vector and ensured that is long enough.

I am using the latest version of VisiLogic (9.8.91) and a V130 with the latest OS. Also, removing the SD card and inserting it back allows me to access the SD card through the SD Card Explorer (which I couldn't do when the bit was locked on), but does not actually reset the bit.

Luke

[AlexUT]

Hi lukeh,

Please provide next information for successful troubleshooting:

1. How many files are in each directory and sub-directory?

*Review help to see limitations.

2. What is a size of each file, especially last you are referring.

*Very long files will make access time unacceptable.

3. When SB344 stuck - scan and repair file structure at PC.

4. Make visual check if a file structure is OK (no strange file names and directory names, etc.).

If there are strange file names and directory names, etc., then backup all data and format SD card again before use.

Show us results.

*It is recommended to review next articles at Unitronics Helpdesk Portal:

https://support.unitronics.com/index.php?/selfhelp/view-article/what-brand-of-sd-cards-can-vision-enhanced-plcs-support-what-is-the-sd-maximum-size-does-it-support-sdhc

https://support.unitronics.com/index.php?/selfhelp/view-article/what-do-i-need-to-do-before-i-can-use-a-sd-card-with-vision-controllers

https://support.unitronics.com/index.php?/selfhelp/view-article/prepare-disk-on-key-dok-or-sd-card-to-work-with-plc

B.R.

 

[lukeh]

Hi,

1) I am writing to a single CSV file exclusively and am just appending rows to that one file.

2) In my testing the file has never gotten above 20 KB. At what point would it become unfeasible to write to that single file? Once this is implemented the file could get quite large, but that is not the case right now.

3/4) I am using a 32GB SDHC card. I originally had some issues formatting the card and I saw on a forum that the SD Card Suite sometimes has issues with formatting 32GB cards. I thought I had resolved that issue, but that could be a factor. Visually the file structure looks ok and I haven't noticed anything unusual.

Luke

[Ausman]

1 hour ago, lukeh said:

am just appending rows to that one file

How often/what time interval?

And Alex, pls note another reference to SD cards becoming much bigger off the shelf than what the card system was first brought up on, and this possibly creating issues.

cheers, Aus

[lukeh]

Hi Aus,

How often and total recording time are both still TBD. How often is going to be configurable on the HMI and total recording time is flexible depending on what is possible. I want a sense of how much data can be written to the file before it becomes an issue so that I can set constraints on how often/total recording time if the user would ever approach that limit.

Luke

[Ausman]

I asked how often as all things SD are slooowwww.  If you try to do something too quickly on top of a previous request, you'll run into trouble.  SI66-69, 330-333, SB217-219, 324-329, 346-349, 352, 358, and any others I've missed can all be used to ensure things go as wanted.

Sometimes for newer cards that are natively too big for manager to like, I have resized it's partition and then it's happy.

cheers, Aus