Tag will read bit status from plc but wont write

I have a UDT that matched the PLC UDT and I have verified the tag path. I have also set the bi directional option for this
tag. the problem is that if i toggle the bit in ignition the plc does not see it, but if i toggle the bit in the plc ignition sees it change state. This setup works elsewhere but i cant figure out why this is happing

Has the access rights for the instancied tag have been overwritten and set to Read Only ?

No but i did find that when i set my usage to output in studio 5000 you can no longer write to that tag, and since it is
a UDT i cannot isolate a single tag within the udt. I was passing the value from a local UDT tag to global using this method but all other functions were interrupted.

As you’ve found, I believe outputs are read-only in later versions of RSLogix 5000 / Studio 5000. I’m not sure I understand exactly what you’re doing, but if the issue is you want to pass this UDT from an add on instruction to a global tag, specifying it as an In/Out type (passes by reference so AOI works directly on global tag rather than copying from/to it via In and Out tags) in the AOI may be what you are looking for.

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