# Legacy ControlLogix tags are coming in with BAD quality

**URL:** <https://forum.inductiveautomation.com/t/legacy-controllogix-tags-are-coming-in-with-bad-quality/43136>\
**Category:** Ignition\
**Tags:** ignition81\
**Created:** [February 8, 2021, 6:01pm UTC](https://forum.inductiveautomation.com/t/legacy-controllogix-tags-are-coming-in-with-bad-quality/43136 "2021-02-08T18:01:14Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![Ali.Etezadkhah](https://avatars.discourse-cdn.com/v4/letter/a/b19c9b/32.png) [@Ali.Etezadkhah](https://forum.inductiveautomation.com/u/Ali.Etezadkhah)\
**Post date:** [February 8, 2021, 6:01pm UTC](https://forum.inductiveautomation.com/t/legacy-controllogix-tags-are-coming-in-with-bad-quality/43136/1 "2021-02-08T18:01:15Z")

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Good morning,

I have established communication with a ControlLogix PLC running 20.19 firmware using Ignition’s Legacy AB driver. The Gateways shows the PLC as connected.

 ![ab1](https://us1.discourse-cdn.com/inductiveautomation/original/3X/3/8/38ceb72a23a50cdc73584f43239a397620e339e7.jpeg)

I can see the tag values in RSLinx.

 ![ab2](https://us1.discourse-cdn.com/inductiveautomation/original/3X/2/e/2e2d7ab6de28415ab8803579c53d985e4f918953.jpeg)

I can browse the tags in Designer and drag them into the Tag Browser, but all the values are BAD.

![ab3](https://us1.discourse-cdn.com/inductiveautomation/original/3X/6/b/6bba2b23ab5612ad5254cc1e1ffe7ec802c8e937.jpeg)

The diagnostic page for one of the tags shows valid tag definition and tag group.

 ![ab4](https://us1.discourse-cdn.com/inductiveautomation/original/3X/3/e/3e9738bb341e04aee9d30dd1c038121fcee18104.jpeg)

Any ideas why the values are not coming through?

Thank you,  
Ali

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**Author:** ![Tim](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/tim/32/3361_2.png) [@Tim](https://forum.inductiveautomation.com/u/Tim)\
**Post date:** [February 8, 2021, 6:11pm UTC](https://forum.inductiveautomation.com/t/legacy-controllogix-tags-are-coming-in-with-bad-quality/43136/2 "2021-02-08T18:11:27Z")

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With 20.19 you need to use the Allen-Bradley Logix Driver (v21+)

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**Author:** ![Kevin.Herron](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/kevin.herron/32/7259_2.png) [@Kevin.Herron](https://forum.inductiveautomation.com/u/Kevin.Herron)\
**Post date:** [February 8, 2021, 6:17pm UTC](https://forum.inductiveautomation.com/t/legacy-controllogix-tags-are-coming-in-with-bad-quality/43136/3 "2021-02-08T18:17:23Z")

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@Tim is correct, and we’re going to be updating the descriptions of the drivers to make this more clear.

Last week we loaded various firmware versions onto a controller here and confirmed that the legacy driver works through v20.18 but in v20.19 they disabled direct memory access (AND they did not implement instance-based access either, so it’s a truly worst-case version to be on performance-wise).

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**Author:** ![Ali.Etezadkhah](https://avatars.discourse-cdn.com/v4/letter/a/b19c9b/32.png) [@Ali.Etezadkhah](https://forum.inductiveautomation.com/u/Ali.Etezadkhah)\
**Post date:** [February 8, 2021, 6:27pm UTC](https://forum.inductiveautomation.com/t/legacy-controllogix-tags-are-coming-in-with-bad-quality/43136/4 "2021-02-08T18:27:16Z")

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Thank you very much for the quick solution 😃