# General

**URL:** https://discourse.nodered.org/c/general/7.md?page=496

[Latest](https://discourse.nodered.org/latest.md) · [Categories](https://discourse.nodered.org/categories.md) · [Tags](https://discourse.nodered.org/tags.md)

**Page:** 497

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## [I need help with a node-red-contrib-tplink-tapo-connect-api](https://discourse.nodered.org/t/i-need-help-with-a-node-red-contrib-tplink-tapo-connect-api/50919)

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**Author:** [@Nicco02F](https://discourse.nodered.org/u/Nicco02F)\
**Replies:** 1\
**Last updated:** [12 September 2021 11:58 UTC](https://discourse.nodered.org/t/i-need-help-with-a-node-red-contrib-tplink-tapo-connect-api/50919 "2021-09-12T11:58:41Z")

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Hi everyone, I downloaded this node: "node-red-contrib-tplink-tapo-connect-api" I can, through msg.payload = 1 ", turn on or off the light bulbs I have in the house PROBLEM: I can't change the color or brightness of the…

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## [Multiple subflows with context variables in a tab](https://discourse.nodered.org/t/multiple-subflows-with-context-variables-in-a-tab/50916)

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**Author:** [@krambriw](https://discourse.nodered.org/u/krambriw)\
**Replies:** 10\
**Last updated:** [12 September 2021 11:57 UTC](https://discourse.nodered.org/t/multiple-subflows-with-context-variables-in-a-tab/50916 "2021-09-12T11:57:47Z")

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Hello, I have a little problem understanding & figuring out how I can have multiple subflows on the same tab flow where each subflow needs to have it's own variables in context As example, I have this test flow below. …

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## [Setting properties of link nodes...from flow](https://discourse.nodered.org/t/setting-properties-of-link-nodes-from-flow/50917)

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**Author:** [@krambriw](https://discourse.nodered.org/u/krambriw)\
**Replies:** 1\
**Last updated:** [12 September 2021 11:02 UTC](https://discourse.nodered.org/t/setting-properties-of-link-nodes-from-flow/50917 "2021-09-12T11:02:40Z")

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Hello, I'm looking for if it would be possible to set properties of link nodes programmatically (from javascript or from another node in the flow)? It is the name of the link node I would like to set Best regards, Walte…

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## [How to use painless mesh with node red](https://discourse.nodered.org/t/how-to-use-painless-mesh-with-node-red/50912)

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**Author:** [@Eldho-Abraham-coder](https://discourse.nodered.org/u/Eldho-Abraham-coder)\
**Replies:** 5\
**Last updated:** [12 September 2021 10:12 UTC](https://discourse.nodered.org/t/how-to-use-painless-mesh-with-node-red/50912 "2021-09-12T10:12:00Z")

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see https://github.com/gmag11/painlessMesh this is mesh technology for esp8266 family of wifi microcontrollers is the a node available to be part of this mesh technology.

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## [Climacell weather API V4](https://discourse.nodered.org/t/climacell-weather-api-v4/50765)

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**Author:** [@grumpazoid](https://discourse.nodered.org/u/grumpazoid)\
**Replies:** 2\
**Last updated:** [12 September 2021 09:09 UTC](https://discourse.nodered.org/t/climacell-weather-api-v4/50765 "2021-09-12T09:09:35Z")

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I noticed my climacell weather data had stopped updating. It appears they have now become tomorrow.io and changed their API to ver4. Has anyone had any success using V4 from within Node Red? I have a new api key but I …

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## [One tcp requests with multiply source port](https://discourse.nodered.org/t/one-tcp-requests-with-multiply-source-port/50629)

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**Author:** [@bar-shiratech](https://discourse.nodered.org/u/bar-shiratech)\
**Replies:** 12\
**Last updated:** [12 September 2021 08:55 UTC](https://discourse.nodered.org/t/one-tcp-requests-with-multiply-source-port/50629 "2021-09-12T08:55:41Z")

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Hi All, I wrote a flow that requires me to send multiple tcp requests (because i need a different source port for each request). For example, I have attached a flow that simulates what I need (not my own). In the atta…

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## [How to work out what CRC calculation to use?](https://discourse.nodered.org/t/how-to-work-out-what-crc-calculation-to-use/50913)

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**Author:** [@craigcurtin](https://discourse.nodered.org/u/craigcurtin)\
**Replies:** 1\
**Last updated:** [12 September 2021 07:51 UTC](https://discourse.nodered.org/t/how-to-work-out-what-crc-calculation-to-use/50913 "2021-09-12T07:51:08Z")

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Guys, I have an undocumented energy meter that i am reading from - i have snooped on the protocol and found information online about similar units so can make some assumptions about the data involved. However i am wond…

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## [Creating flow for DS18B20 sensor and relays on RPI with Node-Red](https://discourse.nodered.org/t/creating-flow-for-ds18b20-sensor-and-relays-on-rpi-with-node-red/50911)

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**Author:** [@blixen66](https://discourse.nodered.org/u/blixen66)\
**Replies:** 4\
**Last updated:** [12 September 2021 07:49 UTC](https://discourse.nodered.org/t/creating-flow-for-ds18b20-sensor-and-relays-on-rpi-with-node-red/50911 "2021-09-12T07:49:44Z")

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I have tried and tried but do not get it, my knowledge is not enough at the moment. I would be very happy if someone could help me with a flow to control a heater using a DS18B20 sensor and two GPIO controlled relays. Re…

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## [Display camera in dashboard](https://discourse.nodered.org/t/display-camera-in-dashboard/50747)

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**Author:** [@Giamma](https://discourse.nodered.org/u/Giamma)\
**Replies:** 11\
**Last updated:** [12 September 2021 05:33 UTC](https://discourse.nodered.org/t/display-camera-in-dashboard/50747 "2021-09-12T05:33:51Z")

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Hi, I have one Reolink RLC-510wa wifi and after reading this post .. I download the flow of @BartButenaers and set this string: ... ffmpeg -rtsp\_transport tcp -i "rtsp://192.168.1.16:554/user=xxxx\_password=xxxx\_ch…

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## [Flow "names" in the edit screen](https://discourse.nodered.org/t/flow-names-in-the-edit-screen/50903)

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**Author:** [@Trying\_to\_learn](https://discourse.nodered.org/u/Trying_to_learn)\
**Replies:** 3\
**Last updated:** [11 September 2021 21:39 UTC](https://discourse.nodered.org/t/flow-names-in-the-edit-screen/50903 "2021-09-11T21:39:14Z")

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NR 2.0.1 I am helping someone and imported a flow. I noticed this. Is that legal?

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## [Display a single line diagram and link field signals (Digital I/Os) to the visual representation](https://discourse.nodered.org/t/display-a-single-line-diagram-and-link-field-signals-digital-i-os-to-the-visual-representation/50899)

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**Author:** [@Isuru](https://discourse.nodered.org/u/Isuru)\
**Replies:** 1\
**Last updated:** [11 September 2021 20:45 UTC](https://discourse.nodered.org/t/display-a-single-line-diagram-and-link-field-signals-digital-i-os-to-the-visual-representation/50899 "2021-09-11T20:45:17Z")

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Hi, I want to display a single line diagram (switching device, transformer, cables) in node red dashboard and link them to the field signals (i.e color change when a breaker is switched on etc.) . Can I achieve this in n…

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## [Create a GPS data framing from several points](https://discourse.nodered.org/t/create-a-gps-data-framing-from-several-points/50884)

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**Author:** [@idiot\_du\_village](https://discourse.nodered.org/u/idiot_du_village)\
**Replies:** 2\
**Last updated:** [11 September 2021 19:54 UTC](https://discourse.nodered.org/t/create-a-gps-data-framing-from-several-points/50884 "2021-09-11T19:54:39Z")

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Hello, I made a robot that avoids obstacles with ultrasonic sensors, it works very well. I added a GPS module to make it work outdoors in a given perimeter, it circulates randomly in the determined perimeter avoiding o…

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## [Onkyo 616 Power-stats](https://discourse.nodered.org/t/onkyo-616-power-stats/50889)

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**Author:** [@Wurmi](https://discourse.nodered.org/u/Wurmi)\
**Replies:** 22\
**Last updated:** [11 September 2021 16:12 UTC](https://discourse.nodered.org/t/onkyo-616-power-stats/50889 "2021-09-11T16:12:28Z")

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I want the use the information i get form my AVR 11.9.2021, 14:48:22node: abc38942f12dbb25 eiscp : msg.payload : Object object command: "system-power" argument: "on" iscp\_command: "PWR01" host: "192.168.1.12" port: "601…

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## [Fs-file-lister is not working](https://discourse.nodered.org/t/fs-file-lister-is-not-working/50731)

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**Author:** [@el\_pablo](https://discourse.nodered.org/u/el_pablo)\
**Replies:** 16\
**Last updated:** [11 September 2021 14:19 UTC](https://discourse.nodered.org/t/fs-file-lister-is-not-working/50731 "2021-09-11T14:19:32Z")

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Hi guys, I'm trying to figure out how to make fs-file-lister to work, but it always return 0 even though there's a file named test.txt and a subfolder named dump in the folder I'm looking into. What am I doing wro…

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## [Arduino - Node-red -sensoren - data convert/split](https://discourse.nodered.org/t/arduino-node-red-sensoren-data-convert-split/50880)

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**Author:** [@dick](https://discourse.nodered.org/u/dick)\
**Replies:** 11\
**Last updated:** [11 September 2021 11:14 UTC](https://discourse.nodered.org/t/arduino-node-red-sensoren-data-convert-split/50880 "2021-09-11T11:14:01Z")

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Hello, Arduino gives data to node-red from sensoren 1 DHT11 for temp, hum, hic (heatindex) 2 CO- sensor for CO Arduino with connection to Node-red gives with debug as follows: "hum 38.00% ; temp 24.00°C ; hic 23.45…

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## [Bigtimer node firing at wrong time](https://discourse.nodered.org/t/bigtimer-node-firing-at-wrong-time/50787)

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**Author:** [@SteveMann](https://discourse.nodered.org/u/SteveMann)\
**Replies:** 15\
**Last updated:** [11 September 2021 04:41 UTC](https://discourse.nodered.org/t/bigtimer-node-firing-at-wrong-time/50787 "2021-09-11T04:41:23Z")

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I have been using BigTimer node to turn on a floodlight at 4:45AM every morning, and off at sunrise. It's been working fine for many months, maybe more than a year. It's disabled in the node during the summer months an…

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## [FATAL ERROR: JavaScript heap out of memory : how to find the guilty?](https://discourse.nodered.org/t/fatal-error-javascript-heap-out-of-memory-how-to-find-the-guilty/50865)

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**Author:** [@waquete](https://discourse.nodered.org/u/waquete)\
**Replies:** 2\
**Last updated:** [10 September 2021 21:14 UTC](https://discourse.nodered.org/t/fatal-error-javascript-heap-out-of-memory-how-to-find-the-guilty/50865 "2021-09-10T21:14:31Z")

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Hi ! I run nodered in docker. My nodered is running correctly but recently I wanted to add a few flows. when I add some flows, after a little time I have a fatal error: FATAL ERROR: Ineffective mark-compacts near hea…

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## [Pinging Network and outputting result via gpio](https://discourse.nodered.org/t/pinging-network-and-outputting-result-via-gpio/50864)

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**Author:** [@Brownjv](https://discourse.nodered.org/u/Brownjv)\
**Replies:** 2\
**Last updated:** [10 September 2021 20:11 UTC](https://discourse.nodered.org/t/pinging-network-and-outputting-result-via-gpio/50864 "2021-09-10T20:11:28Z")

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Hi all, New to Node Red and I am curious what would be the appropriate route for pinging a website or ip address and if the ping is successful activate a gpio pin and if the ping is unsuccessful activate another gpio pi…

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## [Unable to view node status](https://discourse.nodered.org/t/unable-to-view-node-status/50862)

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**Author:** [@Amishman](https://discourse.nodered.org/u/Amishman)\
**Replies:** 1\
**Last updated:** [10 September 2021 20:05 UTC](https://discourse.nodered.org/t/unable-to-view-node-status/50862 "2021-09-10T20:05:25Z")

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I run HA in a virtual machine and installed Node Red through HACS. Everything was working great. I am not sure when this happened but I am not able to view a nodes status or debug messages and more. If I access Node Red …

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## [Received E-Mail has "undefined" payload](https://discourse.nodered.org/t/received-e-mail-has-undefined-payload/12658)

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**Author:** [@S.M](https://discourse.nodered.org/u/S.M)\
**Replies:** 6\
**Last updated:** [10 September 2021 19:05 UTC](https://discourse.nodered.org/t/received-e-mail-has-undefined-payload/12658 "2021-09-10T19:05:06Z")

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Hello! I am trying to send an email with the current temperature measured by an Aqara temperature and humidity sensor. I do receive the email with the set topic, however, the payload in the email says "undefined". I ha…

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## [How to communicate serial in a termux environment](https://discourse.nodered.org/t/how-to-communicate-serial-in-a-termux-environment/50846)

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**Author:** [@hojimint](https://discourse.nodered.org/u/hojimint)\
**Replies:** 2\
**Last updated:** [10 September 2021 16:41 UTC](https://discourse.nodered.org/t/how-to-communicate-serial-in-a-termux-environment/50846 "2021-09-10T16:41:09Z")

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Hello We are trying to implement functions such as Nextion Touchpad by building a local server based on Termux and mqtt borker of an android phone. I installed the node-red-node-serialport pallet to communicate serial w…

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## [Troubleshooting a remote network discovery](https://discourse.nodered.org/t/troubleshooting-a-remote-network-discovery/50853)

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**Author:** [@BartButenaers](https://discourse.nodered.org/u/BartButenaers)\
**Replies:** 4\
**Last updated:** [10 September 2021 16:20 UTC](https://discourse.nodered.org/t/troubleshooting-a-remote-network-discovery/50853 "2021-09-10T16:20:58Z")

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Hi folks, I have a very inconvenient problem with my node-red-contrib-onvif-nodes. Already multiple people have reported that the automatic discovery on Onvif devices doesn't work anymore with latest Github version. P…

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## [Whats the node red low code way to do basic maths on incoming data?](https://discourse.nodered.org/t/whats-the-node-red-low-code-way-to-do-basic-maths-on-incoming-data/50562)

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**Author:** [@craigcurtin](https://discourse.nodered.org/u/craigcurtin)\
**Replies:** 31\
**Last updated:** [10 September 2021 15:52 UTC](https://discourse.nodered.org/t/whats-the-node-red-low-code-way-to-do-basic-maths-on-incoming-data/50562 "2021-09-10T15:52:23Z")

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Guys, I have a stream of data coming out of @Steve-Mcl excellent Buffer-parser node. Some of this I grab and set as Global/FLow Variables for other nodes/flows to access. I need to do some basic arithmetic - i get give…

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## [Handling DB schema changes with open-source projects](https://discourse.nodered.org/t/handling-db-schema-changes-with-open-source-projects/50850)

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**Author:** [@juanh](https://discourse.nodered.org/u/juanh)\
**Replies:** 3\
**Last updated:** [10 September 2021 14:46 UTC](https://discourse.nodered.org/t/handling-db-schema-changes-with-open-source-projects/50850 "2021-09-10T14:46:23Z")

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Hey everyone, I'm somewhat new to NR and working with open-source projects in general. I've created an open-source project, which I am sharing via Github. It has occurred to me that if someone downloads a specific vers…

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## [Turning off/on node state in a flow with ui button help](https://discourse.nodered.org/t/turning-off-on-node-state-in-a-flow-with-ui-button-help/50859)

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**Author:** [@gam3t3ch](https://discourse.nodered.org/u/gam3t3ch)\
**Replies:** 1\
**Last updated:** [10 September 2021 14:23 UTC](https://discourse.nodered.org/t/turning-off-on-node-state-in-a-flow-with-ui-button-help/50859 "2021-09-10T14:23:57Z")

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Trying to accomplish turning the flow of a csv to enable and disable to start and stop the logging. If anyone could help that would be great.

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## [ReferenceError: TextDecoder is not defined in SmartNora update](https://discourse.nodered.org/t/referenceerror-textdecoder-is-not-defined-in-smartnora-update/50857)

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**Author:** [@nygma2004](https://discourse.nodered.org/u/nygma2004)\
**Replies:** 8\
**Last updated:** [10 September 2021 13:45 UTC](https://discourse.nodered.org/t/referenceerror-textdecoder-is-not-defined-in-smartnora-update/50857 "2021-09-10T13:45:41Z")

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Hi All, I was updating my nodes in the palette manager, and amongs others, I updated Smartnora to 1.4.1 (if I remember correctly) After restarting node-red, I found this in the log: 10 Sep 15:04:58 - \[warn\] \[node-red…

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## [Setting Global Configuration Node Properties from within a flow](https://discourse.nodered.org/t/setting-global-configuration-node-properties-from-within-a-flow/50730)

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**Author:** [@juanh](https://discourse.nodered.org/u/juanh)\
**Replies:** 2\
**Last updated:** [10 September 2021 10:33 UTC](https://discourse.nodered.org/t/setting-global-configuration-node-properties-from-within-a-flow/50730 "2021-09-10T10:33:40Z")

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Is it possible to set a Global Configuration Node's properties from within a node? In my use-case, I would like to use a Dashboard UI to allow a user to specify some information, which in turn will be used to set the pr…

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## [Using cosine inside function block for calculation](https://discourse.nodered.org/t/using-cosine-inside-function-block-for-calculation/50839)

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**Author:** [@julianpe](https://discourse.nodered.org/u/julianpe)\
**Replies:** 6\
**Last updated:** [10 September 2021 09:27 UTC](https://discourse.nodered.org/t/using-cosine-inside-function-block-for-calculation/50839 "2021-09-10T09:27:06Z")

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Dear all, I'm playing a little bit with my NodeRed application. I'd like to integrate a current smartmeter which is attached to the ttyUSB0 of my maschine. This works quite good and I get all desired values. Moreover…

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## [MQTT question - LWT and Death Certificates](https://discourse.nodered.org/t/mqtt-question-lwt-and-death-certificates/50742)

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**Author:** [@Trying\_to\_learn](https://discourse.nodered.org/u/Trying_to_learn)\
**Replies:** 11\
**Last updated:** [9 September 2021 21:25 UTC](https://discourse.nodered.org/t/mqtt-question-lwt-and-death-certificates/50742 "2021-09-09T21:25:19Z")

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Sorry, but I'm stuck again. First off this is the message in question: {"topic":"EOM","qos":0,"retain":true,"\_msgid":"73cc5798.fb9508","settings":{"input":"2021-09-07T19:01:01.537Z","input\_format":"","input\_tz":"Austra…

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## [Advice on deploying apps with hardware specific nodes on different platforms](https://discourse.nodered.org/t/advice-on-deploying-apps-with-hardware-specific-nodes-on-different-platforms/50432)

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**Author:** [@blunoz](https://discourse.nodered.org/u/blunoz)\
**Replies:** 18\
**Last updated:** [9 September 2021 20:58 UTC](https://discourse.nodered.org/t/advice-on-deploying-apps-with-hardware-specific-nodes-on-different-platforms/50432 "2021-09-09T20:58:02Z")

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Looking for advice on how to organise an application I've written. The app has two components, the first is a monitor for controlling the fermentation of beer so it senses the temperature and turns solenoids on and off …

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