# Expression tag dependent on its prior value

**URL:** <https://forum.inductiveautomation.com/t/expression-tag-dependent-on-its-prior-value/102607>\
**Category:** Ignition\
**Tags:** ignition81\
**Created:** [February 20, 2025, 5:13am UTC](https://forum.inductiveautomation.com/t/expression-tag-dependent-on-its-prior-value/102607 "2025-02-20T05:13:45Z")\
**Posts on this page:** 1\
**Showing post:** 7

<div class="post-metadata">

**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:** [February 20, 2025, 3:55pm UTC](https://forum.inductiveautomation.com/t/expression-tag-dependent-on-its-prior-value/102607/7 "2025-02-20T15:55:34Z")

</div>

If your real PLCs will be using IA's Logix driver, or Modbus driver, you might find my 3rd party modules helpful. (Allowing all your OPC Item Paths to remain unchanged between simulation and deployment.) Simply disable the simulation code's timer event when deploying.

---

_[View the full topic](https://forum.inductiveautomation.com/t/expression-tag-dependent-on-its-prior-value/102607)._