7.9.9 Logix driver reading String tags from PLC?

Ignition
1

I'm trying to read a string tag from a logix PLC > v21 firmware but all I see when I browse the PLC is:

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StopTime is the string PLC tag name.
I found this old 2008 topic and i've tried using the format suggested, but no dice...

Update 1:
The string used in the PLC is a 26 char string.
This is the opc item path to the tag I can't read:
ns=1;s=[Packaging_WineDelivery]SQ01_CL1PF.Log.StopTime

The PLC guy created a new dummy string tag at the root and I can read this fine :confused:

Update 2:
I can read strings from literally anywhere else but the StartTime and StopTime from within the SQXX_YYY (UDT instance) Log (UDT instance)...
I'm at a loss

2

Was the dummy at the root a 26-char string, or a default 82-char string?

3

If it really is a timestamp, consider switching to an LINT filled by a GSV of WallClock, CurrentValue. That will be microseconds UTC which can be efficiently converted to a java.sql.Timestamp or java.util.Date.

4

Try a later version of 7.9? I vaguely remember some issue in the past with custom strings. Won’t have access to history until Monday to try to look it up.

5

I know I used 7.9.15 and later and had no issues with custom length strings in UDTs and AOIs.

6

It just started working now after the original 6x ints (year,month,day,hour,min,sec) were added back into the UDT…
Originally we were using these ints for the datetime but PLC guy wanted to reduce to a single string tag. INTs were removed and replaced by a 26char string. As in my OP, Ignition was reading this string as its individual components (DATA[] and LEN), however after many many changes to try to work out what’s going on, we ended up giving up and added back in the original 6 INTs but kept the string still there. Then the string started reading properly and showing up as a string and not DATA and LEN components… :thinking: I’m left stumped and very confused…