# Python daemon - MODBUS output signal driven by program running status

**URL:** <https://forum.universal-robots.com/t/python-daemon-modbus-output-signal-driven-by-program-running-status/4487>\
**Category:** URCaps SDK\
**Created:** [June 10, 2019, 10:51pm UTC](https://forum.universal-robots.com/t/python-daemon-modbus-output-signal-driven-by-program-running-status/4487 "2019-06-10T22:51:32Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![anon63318613](https://avatars.discourse-cdn.com/v4/letter/a/5f9b8f/32.png) [@anon63318613](https://forum.universal-robots.com/u/anon63318613)\
**Post date:** [June 10, 2019, 10:51pm UTC](https://forum.universal-robots.com/t/python-daemon-modbus-output-signal-driven-by-program-running-status/4487/1 "2019-06-10T22:51:32Z")

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Hello,

We are developing a URCAP, I’m interfacing with a MODBUS device, there is a robot ready signal that I wish to be automatically driven high when the robot program is running.

When the robot program is paused, there are any errors, the program is stopped or the robot is e-stopped this signal needs to be driven low.

Can you provide an example of the easiest way to achieve this?

Thanks,

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**Author:** ![sam.verity-hilton](https://sea2.discourse-cdn.com/flex020/user_avatar/forum.universal-robots.com/sam.verity-hilton/32/6046_2.png) [@sam.verity-hilton](https://forum.universal-robots.com/u/sam.verity-hilton)\
**Post date:** [June 11, 2019, 8:55am UTC](https://forum.universal-robots.com/t/python-daemon-modbus-output-signal-driven-by-program-running-status/4487/2 "2019-06-11T08:55:49Z")

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Hi @anon63318613

In the installation tab, under I/O setup, find the output you want to configure (be it a MODBUS signal, digital I/O etc), and under the “Action In Program” drop down, select “High when running-low when stopped”, this should give you the functionality you’re looking for.

Hope this helps.

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<div class="post-metadata">

**Author:** ![anon63318613](https://avatars.discourse-cdn.com/v4/letter/a/5f9b8f/32.png) [@anon63318613](https://forum.universal-robots.com/u/anon63318613)\
**Post date:** [June 11, 2019, 12:10pm UTC](https://forum.universal-robots.com/t/python-daemon-modbus-output-signal-driven-by-program-running-status/4487/3 "2019-06-11T12:10:09Z")

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Thanks for this, I will upgrade the software of the robot I’m working with as assigning these behavior’s to MODBUS signals is not possible in this version.

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<div class="post-metadata">

**Author:** ![sam.verity-hilton](https://sea2.discourse-cdn.com/flex020/user_avatar/forum.universal-robots.com/sam.verity-hilton/32/6046_2.png) [@sam.verity-hilton](https://forum.universal-robots.com/u/sam.verity-hilton)\
**Post date:** [June 11, 2019, 12:34pm UTC](https://forum.universal-robots.com/t/python-daemon-modbus-output-signal-driven-by-program-running-status/4487/4 "2019-06-11T12:34:12Z")

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which version of polyscope are you on?