Giorgio

Prevent specific DM memory-areas being changed with logic update

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Starting to find my way around Cx-One, running a CJ2M-CPU33, logic runs a rotary indexing-table destacker weldcell. 

I am trying to figure out a way to prevent changing the value stored in UDINT TOTAL_PART_COUNT D31 when I upload a revision.

The D31 increment line is section Main_Operation:40

It is a cumulative count of all parts run to date, so there is no conceivable reason I am ever going to want the TOTAL COUNT saved in an old revision to overwrite the current value.

 

The cell runs all day every day, so for a revision I'll open the last *.cxp file, connect to PLC, compare PC to PLC, if same I'll "Save", disconnect, make changes, save .cxp as new Rev#, and upload.

When I upload a new revision, I usually (but it seems not always)  overwrite the value stored in UDINT TOTAL_PART_COUNT D31 on the PLC (which of course is bigger than whats in the newer revision since the machine has been running). Usually I remember to write down the TOTAL_PART_COUNT in the PLC before I upload and just manually change it after uploading the new Rev, but when I forget to and realize a week later, I get to have a lot of fun reading paper production logs.

Is there a way to protect certain memory-areas like TOTAL_COUNT from being over-written by a Revision upload? Maybe I need to use a different memory area or instruction set?

Next revision is going to be adding data-logging of faults, I'd like to create 2 arrays per fault, one for fault timestamp and one for # of minutes before the fault was cleared, and I'd certainly wouldn't want those arrays over-written with older values when I upload future revisions. Are the EM Memory Area values implicitly protected from overwrite?

PS. The 13.15 "Trash Bit" contact everywhere  is from the integrator, not me, I have at least figured out the P_Off flag

AS-260 IL100 LASER PARTSTCK REV23 2.27.17.cxp

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Uploading a program change does not normally modify the DM memory area unless you specifically tell CXP to upload the DM Area.

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Thanks, do you know where we tell CXP to upload the DM area?

Another user uses CXP on my laptop under their profile, wondering if when they use it they change one of my settings or something.

 

Whenever I've done a PLC -> Transfer -> Download to PLC , I've always clicked the "Transfer All" box,

sometimes D31 is updated with the value I last saved, oftentimes not.

In the "Download Options" popup box that comes up I didn't see a specific option for uploading DM Memory Area, or any memory area for that matter, so I'm guessing its somewhere else

 

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 I am less concerned with uploading the DM area from the PLC than I am with not DOWNloading the old saved DM values TO the PLC, so whichever setting prevents downloading DM values to the PLC would be helpful to know.

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Open the memory view in CXP. Under the Online tab select Transfer From (or To) PLC.

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Another thought ...... you have a CPU33 so it will have the EM0 memory area. If you aren't using that area for anything you could easily create a backup copy of the D32 register in an EM register (like E0_32). If you do that then you can create a rung which compares those two values and sets both registers to the largest value.

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As Dick states above, it is a separate, manual process to download the DM values to the PLC, so it is not coming from your download.  If there is a memory card in the PLC, it is possible that it is coming from the card, but you would expect that it would happen every time.  Is it possible that it is coming from either of your EtherNet/IP connections? 

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No memory card, the CJ1 Ethernet/IP card goes to HMI, Remote I/O nodes and the 3 Weldgun motors. HMI used to be able to change D31 TOTAL COUNT, SHIFT COUNT, etc  through the keypad but I took that out (at least I think I did, now I want to double-check, easy for an operator to fat-finger). 

I have opened the Memory window and clicked the icon for "Upload from PLC", come to think of it, I think the only times I have had issues with D31 being changed were the times I did open the Memory window and "Upload from PLC", I'm pretty sure I didn't do anything else except Upload.  

Edited by Giorgio

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I have opened the Memory window and clicked the icon for "Upload from PLC"

If Memory Window asks to save in project, you may be keeping a DM file inside your project.  You would have to download it from the Memory Window utility though.

BTW: Are you working in the Lawrenceburg Toyota Plant?

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Helped with a few Komatsu press installs at the Georgetown Toyota Plant when TMMK replaced them all with servos. I didn't know there was a Toyota Plant in Lawrenceburg, I worked for the HURCO/Chiron dealer out of Lawrenceburg doing cnc installs for a little while.

Just started work for one of their Tier 1  stamping suppliers near my house. Kinda funny out of a string of Japanese plants this has been the first Omron shop so far, all the rest were AB, except Hitachi was a mixture, mostly Mitsubishi, & the Georgetown Toyota plant which used a mixture but standardizing on non-US Keyence & their ToyoPUCs

Yeah in the Memory window I've done "Upload from PLC", I dont think I've explicitly clicked "Save" or been prompted to save when in the Memory window,

I've done "Save As" from the main menu while in the Memory Screen, & I have saved when I got the "do you want to save ___" grey popup box when I try to close the project, and the DM Values are there when I open the project up  so I'm guessing one of those has saved a local copy of DM and EM0 on my laptop. I don't think I ever clicked the "Download to PLC" icon

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