# No viable alternative at input B10?

**URL:** <https://forum.inductiveautomation.com/t/no-viable-alternative-at-input-b10/104600>\
**Category:** Ignition\
**Created:** [April 2, 2025, 5:47pm UTC](https://forum.inductiveautomation.com/t/no-viable-alternative-at-input-b10/104600 "2025-04-02T17:47:49Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![colten.davis](https://avatars.discourse-cdn.com/v4/letter/c/a5b964/32.png) [@colten.davis](https://forum.inductiveautomation.com/u/colten.davis)\
**Post date:** [April 2, 2025, 5:47pm UTC](https://forum.inductiveautomation.com/t/no-viable-alternative-at-input-b10/104600/1 "2025-04-02T17:47:49Z")

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Hi all. Absolute newbie. I'm trying use a push button to write a 1 to a boolean address in a MicroLogix 1100. I can get a toggleSwitch to work and write a 1, but I'm struggling with the script method. Please send help.

 ![buttonScript](https://us1.discourse-cdn.com/inductiveautomation/original/3X/a/3/a3b45a5a8e0cca8dbf60bb69cb3d2990f43990dd.png)  
 ![buttonScriptFault](https://us1.discourse-cdn.com/inductiveautomation/original/3X/4/d/4db490397e3c7287eb80a4952146f13fb0787daa.png)

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**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:** [April 2, 2025, 5:48pm UTC](https://forum.inductiveautomation.com/t/no-viable-alternative-at-input-b10/104600/2 "2025-04-02T17:48:30Z")

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You need to make your tag path a string with quotation marks.

Edit: And if you want to write directly to a device, you need to use `system.opc.write...()`. `system.tag.*` functions work with tags in Ignition.

{Terminology note: "tags" is an overloaded word. In most PLCs, they are named addresses. In some PLCs their names are the actual "addresses" for external protocols. In any case, when an OPC server's driver connects to a PLC, its addresses/tags/symbols/whatever are represented as OPC _ **Items** _ or _ **Nodes** _, not "tags". In Ignition, "tags" are Ignition's internal live value data points, which _ **may be** _ connected to OPC Items/Nodes.}