forcing bits on and off Logix 5000

[fuzzy logic]

Just to add a reference to a manual that could explain you the concept for I/O Mapping (aka Buffer I/O):

Chapter 1 starting page 21
http://literature.rockwellautomation.com/idc/groups/literature/documents/pm/1756-pm004_-en-p.pdf

- fuzzy logic

 

[showshocka]

Somewhere in the program the real input for that PE should be mapped to the tag you are looking at. A cross reference of the tag should lead you back to that input.

this is where it took me to. does that mean this is input I:3/1?

 

[daba]

The bit you are trying to force is definitely not a real, physical I/O bit.

All Logix5000 I/O tags are created automatically when an I/O module is inserted into the I/O Configuration.

All Logix5000 I/O tags have the generic format of :-

Location : Slot : Data Type


Location - will always be "Local" for modules in the same chassis as the controller. When located in a remote chassis, the Location is the name assigned to the remote communications module in the I/O configuration.

Slot - speaks for itself, slot number where the module resides in the chassis (remember they are numbered left-to-right, starting at Slot 0).

Data Type - This will be either I, for data coming Into the controller, or O, for data going Out of the controller.

[Note : There will be another tag created associated with a module, that is the "C" tag. This tag contains the module configuration which is downloaded to the module at power-on, once accepted, the module will communicate with the controller.]

Typically then, I/O tags will look like Local:4:I and you open up these tags to get at the I/O data.

Examples :-

You want to look at bit 7 of an Input module in slot 14 - the tag will be Local:14:I.Data.7.

Output bit 26 of an output module in slot 9 of a remote chassis via an Ethernet or ControlNet communication module (doesn't matter which) named "Albert" in the I/O configuration will have the tag Albert:9:O.Data.26


These I/O tag formats are fixed, therefore you I_3.11 is not an I/O tag. Because it is named that way (i.e. I_3), I would guess that the system has been converted and updated from an earlier hardware platform (e.g. PLC5 or SLC) that uses I/O addresses.

As has already been said, it is most likely this tag is "mapped" from the real I/O point somewhere in the code, and cross-referencing it will reveal where.

 

[showshocka]

That looks like an aliased tag, can you post the program?(zipped)

sure. because i have no idea now....

 

[TConnolly]

Showshocka,

Look at the upper left hand corner of the screen shot you posted. Do you see that status that says IO NOT RESPONDING. It should read IO OK. Expand your IO configuration and find out what IO isn't working.

 

[daba]

this is where it took me to. does that mean this is input I:3/1?

Yes - go to the tag Local:3:I in the database (or right-click it on the ladder and choose "Monitor....")

Expand the tag (click the + sign to the left), and find the ".Data" element.

Expand .Data (click the + sign to the left), and you will see the individual bits.

To force this input ON, put a 1 in the "Force Mask" column.

Forces will most likely be disabled at this point, so you will need to enable I/O forces in the Online Toolbar (top left of the screen).

In general - Be wary about just enabling forces - you ought to check that there aren't any others installed (perhaps by someone else a long time ago). When you enable/disable forces, you enable/disable all of them. !! In your case there are no forces installed, but they are enabled, so putting a 1 in the force column will take effect immediately.

 

[TConnolly]

To post a program right click on the ACD file and pick Send to Compressed Folder. Follow the prompts. This will crete a ZIP file that you can attach to a post the same way you attached the screen shots.


BTW, you can also force from the tag list. Open the tag list, select the Monitor Tags tab and you'll see a column called force mask. You can place a 1 or 0 in this column to force the tag. Find the actual tag for the input in the list, not an alias or buffered tag, and force that tag.

 

[fuzzy logic]

Beside the excellent daba's post, I may say you're indicating a legacy addressing mode, like the one inside SLC-500 (I:3/1)... actually your real I/O tag is exactly the one indicated in the source operand of the COP instruction (Local:3:I.Data).
You module is inside slot number 3.
You may Force that tag, and all its bits; also you'll able to Force all the Alias tags pointing to that data.
Your case is different, data are mapped (copied) inside another tag, so no way to force the I_3 tag and its alias.

edit : Apologize, this post is arrived quite late to be shown after other similar messages... you're so quick guys !!!

- fuzzy logic

 

[showshocka]

Showshocka,Expand your IO configuration and find out what IO isn't working.

yes, i looked and i have a 1756 DHRIO card that's saying it faulted. i reset the card, there was no fault on the the backplane to reset. I tried a new card with address changed to the same as the first one and i still received the same fault. scrolling across the card is "A OK B #07 NODE ONLY", the B led is flashing.

 

[showshocka]

Y
In general - Be wary about just enabling forces - you ought to check that there aren't any others installed (perhaps by someone else a long time ago).

its most likely there are no other forced inputs in the project, but i will be careful. yes, this is a newly upgraded line from SLC500.

 

[asterof]

thats a conversion from a SLC5 I would bet
Done enought of those
Someone used the silly conversion program that produces
an alias of an alias to the real input device.
Keep digging it is way down in there, thus the reason never to use that conversion program.
Your real input will look something like
Rack3:1:I.10 or Input_1.10

 

[showshocka]

You module is inside slot number 3.
You may Force that tag, and all its bits; also you'll able to Force all the Alias tags pointing to that data.
Your case is different, data are mapped (copied) inside another tag, so no way to force the I_3 tag and its alias.

edit : Apologize, this post is arrived quite late to be shown after other similar messages... you're so quick guys !!!

- fuzzy logic

i'm at the location of the bits and the program will not allow me to put any 1's or 0'2 in the force mask column.

 

[Andrew_W]

You need to find the tag Local:3:I.Data.11 assuming its your 11th input on your card just guessing it is from where your cursor was in the screen shot, then it should allow you to force it

i'm at the location of the bits and the program will not allow me to put any 1's or 0'2 in the force mask column.

 

[danny.michael]

At the top of the tag monitor window, click the "Show" button. Select "Can be forced". This will limit the tag view to real I/O only. The input you're looking for is at Local:3:I.Data.11.

Also, if the DHRIO module is not controlling anything on RIO (and it appears it isn't), take it out of the I/O tree. There is no need to add a DHRIO module to the tree unless it's controlling I/O. That will get rid of the I/O not responding error.

 

[daba]

showshocka - I did tell you in post #18 that I_3 is not a physical I/O tag and therefore cannot be forced. Nor is I_3 an alias to a physical I/O, and therefore again cannot be forced.

The internal tag I_3 is mapped in logic (using a COP instruction) from Local:3:I.Data. My post #21 told you where to go to do your forcing.


For the I/O Not Responding ststus - Some DHRIO modules (Rev.6 was one) will show as an I/O error if both channels are set to DH+ mode. (No doubt Ken will know revisions and more details...)

So, if both channels are used for DH+ comms, there is no need for it to be in the I/O Configuration "tree", since it is not being used for I/O, it can safely be removed, and the "I/O Not Responding" status should rectify itself.

Any comms "paths" that are specified in MSG configurations (i.e. the DHRIO module is quoted by name), will revert back to their explicit, numerical, form - Port, Destination, Port, Destination, etc.

If anyone wants more detail of communications "Paths" and how they can be specified, just ask