# Problem on Allen-Bradley Logix Driver array of bit

**URL:** <https://forum.inductiveautomation.com/t/problem-on-allen-bradley-logix-driver-array-of-bit/73587>\
**Category:** Ignition\
**Tags:** ignition81\
**Created:** [May 11, 2023, 12:30pm UTC](https://forum.inductiveautomation.com/t/problem-on-allen-bradley-logix-driver-array-of-bit/73587 "2023-05-11T12:30:55Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![g.bonomini](https://avatars.discourse-cdn.com/v4/letter/g/b5ac83/32.png) [@g.bonomini](https://forum.inductiveautomation.com/u/g.bonomini)\
**Post date:** [May 11, 2023, 12:30pm UTC](https://forum.inductiveautomation.com/t/problem-on-allen-bradley-logix-driver-array-of-bit/73587/1 "2023-05-11T12:30:55Z")

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Hello guys,  
i have a AB CPU v34 with a program with many UDT used. The problem is from Ingition gateway OPC client of OPC UA of Ignition i can't see all of elements of array of bool with 160 elements. In my case I can see only first 5 elements.  
Is very strange because at same level of nidification of tags I tried to put an array of 160 elements but integer. By OPC client I can see all 160 elements.  
I tried also to create a new array of bool with 160 elements and in the newest I can see only first 4 elements.  
There is some limitation of nidification in AB PLC?  
Obiusvully in Ignition Designar I can see only tag I can see on OPC client.  
Do you have any idea to solve?

Thanks

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**Author:** ![pturmel](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/pturmel/32/3295_2.png) [@pturmel](https://forum.inductiveautomation.com/u/pturmel)\
**Post date:** [May 11, 2023, 12:49pm UTC](https://forum.inductiveautomation.com/t/problem-on-allen-bradley-logix-driver-array-of-bit/73587/2 "2023-05-11T12:49:12Z")

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Logix boolean arrays are really DWORD arrays, where each dword supplies 32 of the booleans. Drill in deeper. Your original boolean address of `somebooltag[B]` translates to an OPC Item Path of `somebooltag[J].K` where J=B/32 and K=B%32.

And no, this is not a bug. The logix processor really does tell a connected system that these are DWORDs. The only booleans that are actually reported as true booleans are stand-alone boolean tags (non-array). Even booleans within UDTs aren't "real" booleans, as they are hosted in some other integer type (hidden SINTs, typically).

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**Author:** ![g.bonomini](https://avatars.discourse-cdn.com/v4/letter/g/b5ac83/32.png) [@g.bonomini](https://forum.inductiveautomation.com/u/g.bonomini)\
**Post date:** [May 11, 2023, 1:39pm UTC](https://forum.inductiveautomation.com/t/problem-on-allen-bradley-logix-driver-array-of-bit/73587/3 "2023-05-11T13:39:45Z")

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Thanks a lot!!! You solved my problem!  
Before to ask I tried to find some documentation but I haven't find.  
Thenks