# Older Version 7.6.6 and CompactLogix V20 **URL:** \ **Category:** Ignition\ **Created:** [August 8, 2019, 11:37am UTC](https://forum.inductiveautomation.com/t/older-version-7-6-6-and-compactlogix-v20/27261 "2019-08-08T11:37:56Z")\ **Posts on this page:** 6\ **Page:** 1
**Author:** ![ClemsonTim80](https://avatars.discourse-cdn.com/v4/letter/c/edb3f5/32.png) [@ClemsonTim80](https://forum.inductiveautomation.com/u/ClemsonTim80)\ **Post date:** [August 8, 2019, 11:37am UTC](https://forum.inductiveautomation.com/t/older-version-7-6-6-and-compactlogix-v20/27261/1 "2019-08-08T11:37:56Z")
I have a site that has worked fine for years using 7.6.6 that is connected to a ControlLogix V20 based Gateway and my customer just swapped out a SLC 5/04 DH+ device with a CompactLogix L30ER V20 firmware. I can setup up the device, it connects fine showing Connected: EIP - Run Mode. I can use the Quick Client to browse the processor tags fine, but when I try to Read or Subscribe from the Quick Client I get a valid Timestamp, Status:Unknown / Value:null / Quality: Uknown. I am working on upgrading them to 7.9 today but I need to try to get this device working temporarily while all of the POs go through. I know there are issues with 7.6 regarding Logix V21 and higher, but I would have thought that the included Allen-Bradley CompactLogic - Connect To CompactLogix firmware v20 and prior processors should work. Any ideas ? ---
**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:** [August 8, 2019, 11:45am UTC](https://forum.inductiveautomation.com/t/older-version-7-6-6-and-compactlogix-v20/27261/2 "2019-08-08T11:45:02Z")
Let me guess… it’s firmware v20.15 or higher? Rockwell disabled the direct memory access method in later revisions of firmware 20. The latest one that I know for sure works with the old Compact/ControlLogix drivers is 20.11. ---
**Author:** ![ClemsonTim80](https://avatars.discourse-cdn.com/v4/letter/c/edb3f5/32.png) [@ClemsonTim80](https://forum.inductiveautomation.com/u/ClemsonTim80)\ **Post date:** [August 8, 2019, 11:50am UTC](https://forum.inductiveautomation.com/t/older-version-7-6-6-and-compactlogix-v20/27261/3 "2019-08-08T11:50:19Z")
I can’t get online with it directly from here but just using a Browser to the IP Address it says 1769-L30ER/A LOGIX5330ER Product Revision 20.019 Build 98 Firmware Version Date May 28 2015 14:41:59 ---
**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:** [August 8, 2019, 12:12pm UTC](https://forum.inductiveautomation.com/t/older-version-7-6-6-and-compactlogix-v20/27261/4 "2019-08-08T12:12:59Z")
Yeah… 20.19. You’ll need to upgrade and use the Logix v21 driver. The performance will not be good since it has to read using symbolic addressing instead of DMA or instance-based. Alternatively, you can use RSLinx or Kepware and make an OPC connection, if upgrading Ignition isn’t an option there. ---
**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:** [August 8, 2019, 12:16pm UTC](https://forum.inductiveautomation.com/t/older-version-7-6-6-and-compactlogix-v20/27261/5 "2019-08-08T12:16:00Z")
You could also temporarily downgrade the firmware. ---
**Author:** ![ClemsonTim80](https://avatars.discourse-cdn.com/v4/letter/c/edb3f5/32.png) [@ClemsonTim80](https://forum.inductiveautomation.com/u/ClemsonTim80)\ **Post date:** [August 8, 2019, 12:36pm UTC](https://forum.inductiveautomation.com/t/older-version-7-6-6-and-compactlogix-v20/27261/6 "2019-08-08T12:36:43Z")
Thanks guys - not my equipment so firmware downgrade is probably not an option. I may give RSLinx a shot for a temporary band aid, but I guess I’ll have to try to speed up the upgrade process.