# Read barcode string from S7 to Ignition

**URL:** <https://forum.inductiveautomation.com/t/read-barcode-string-from-s7-to-ignition/111493>\
**Category:** Ignition\
**Tags:** ignition81, ignition80, perspective\
**Created:** [October 15, 2025, 11:26pm UTC](https://forum.inductiveautomation.com/t/read-barcode-string-from-s7-to-ignition/111493 "2025-10-15T23:26:00Z")\
**Posts on this page:** 1\
**Showing post:** 4

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**Author:** ![David\_Stone](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/david_stone/32/79749_2.png) [@David\_Stone](https://forum.inductiveautomation.com/u/David_Stone)\
**Post date:** [October 21, 2025, 7:11am UTC](https://forum.inductiveautomation.com/t/read-barcode-string-from-s7-to-ignition/111493/4 "2025-10-21T07:11:34Z")

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This is because you are not populating the length of the string in the PLC.  
Refer to this post from the forum:

> [@Siemens string address syntax](https://forum.inductiveautomation.com/t/siemens-string-address-syntax/68353/8):
>
> The Siemens string format that Ignition expects to find at offset 80 starts with two non-string bytes-max length and occupied length. The 18 bytes of actual string follow that, and Ignition will only use the "occupied" length to construct its result. Verify that you have the correct max and actual lengths in those two leading bytes.

In the pictures above, you show that the Max Length in bytes is 1, and there are 0 characters in the string, so Ignition will display nothing.

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