# General

**URL:** https://discourse.nodered.org/c/general/7.md?page=453

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

**Page:** 454

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## [How to connect api rest with node-red](https://discourse.nodered.org/t/how-to-connect-api-rest-with-node-red/55107)

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**Author:** [@Kirox120](https://discourse.nodered.org/u/Kirox120)\
**Replies:** 3\
**Last updated:** [13 December 2021 11:00 UTC](https://discourse.nodered.org/t/how-to-connect-api-rest-with-node-red/55107 "2021-12-13T11:00:10Z")

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hello i need to make iot project with raspberry pi , when RFID receive tag id from the sensor it checks if this tag id is exist on the database phpmyadmin , i insert ID and name on databse manually and i should retur…

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## [After change node not comparing on function node](https://discourse.nodered.org/t/after-change-node-not-comparing-on-function-node/55070)

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**Author:** [@aminulhaq](https://discourse.nodered.org/u/aminulhaq)\
**Replies:** 14\
**Last updated:** [13 December 2021 10:24 UTC](https://discourse.nodered.org/t/after-change-node-not-comparing-on-function-node/55070 "2021-12-13T10:24:48Z")

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Hi, using change node to convert PLC address to some readable format so that i can use it on function node, i doing this because i dont know how to use ALLEB BRADLY PLC address to function node after that i am comparing…

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## [ASCOM Alpaca & NodeRed for Open Astronomy](https://discourse.nodered.org/t/ascom-alpaca-nodered-for-open-astronomy/54931)

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**Author:** [@widobsono](https://discourse.nodered.org/u/widobsono)\
**Replies:** 4\
**Last updated:** [13 December 2021 06:22 UTC](https://discourse.nodered.org/t/ascom-alpaca-nodered-for-open-astronomy/54931 "2021-12-13T06:22:37Z")

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Hello good people, I hope all of you are doing great and healthy, mentally and physically. I am an amateur astronomer and now working in an backyard Observatory and Planetarium called ImahNoong, located in Lembang, Ind…

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## [Variable payload syntax](https://discourse.nodered.org/t/variable-payload-syntax/55091)

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**Author:** [@pinie\_pinie](https://discourse.nodered.org/u/pinie_pinie)\
**Replies:** 2\
**Last updated:** [12 December 2021 20:37 UTC](https://discourse.nodered.org/t/variable-payload-syntax/55091 "2021-12-12T20:37:05Z")

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Hi there, to control a thermostat (tuya) I generate the following payload with an inject-node (see photo). That works fine. Now I would like to hand over control to a slider node. Unfortunately I don't know the syntax. …

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## [How to post to nodered http in using lambda and api gateway](https://discourse.nodered.org/t/how-to-post-to-nodered-http-in-using-lambda-and-api-gateway/55089)

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**Author:** [@Aron-Chu](https://discourse.nodered.org/u/Aron-Chu)\
**Replies:** 3\
**Last updated:** [12 December 2021 18:40 UTC](https://discourse.nodered.org/t/how-to-post-to-nodered-http-in-using-lambda-and-api-gateway/55089 "2021-12-12T18:40:27Z")

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I was wanting to post a single string to nodered but was just wondering if I needed to do something special like formatting to msg.payload or using the change node. Quite new to nodered so was just wanting to get pointed…

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## [Extracted from a part of a chain](https://discourse.nodered.org/t/extracted-from-a-part-of-a-chain/55082)

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**Author:** [@Manu110](https://discourse.nodered.org/u/Manu110)\
**Replies:** 5\
**Last updated:** [12 December 2021 17:04 UTC](https://discourse.nodered.org/t/extracted-from-a-part-of-a-chain/55082 "2021-12-12T17:04:34Z")

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Hello. I am starting with nodeRed. I am looking for how it can be extracted from a part of a chain, I expose the message that is received. "C, \*, 1234, Z". I want to get the value '1234'. How should I do it in a func…

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## [Change node unexpected behavior](https://discourse.nodered.org/t/change-node-unexpected-behavior/55078)

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**Author:** [@peterda](https://discourse.nodered.org/u/peterda)\
**Replies:** 2\
**Last updated:** [12 December 2021 14:56 UTC](https://discourse.nodered.org/t/change-node-unexpected-behavior/55078 "2021-12-12T14:56:27Z")

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Change node has unexpected behavior. Maybe my understanding of this node is wrong, or is it? The change node receives msg.payload "on" and should replace that with {"state";"OFF"}. As seen in the debug output it ju…

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## [Node-red-contrib-heater-controller problem](https://discourse.nodered.org/t/node-red-contrib-heater-controller-problem/55053)

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**Author:** [@magicman](https://discourse.nodered.org/u/magicman)\
**Replies:** 6\
**Last updated:** [12 December 2021 14:42 UTC](https://discourse.nodered.org/t/node-red-contrib-heater-controller-problem/55053 "2021-12-12T14:42:09Z")

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Hi not sure if anyone can help? Used to use this controller before its update by inputting a targetValue into the controller thus allowing me to use Alexa to change heating thermostat, since the update it wants me to us…

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## [Unable access node-red via browser](https://discourse.nodered.org/t/unable-access-node-red-via-browser/54983)

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**Author:** [@zyx09](https://discourse.nodered.org/u/zyx09)\
**Replies:** 15\
**Last updated:** [12 December 2021 12:45 UTC](https://discourse.nodered.org/t/unable-access-node-red-via-browser/54983 "2021-12-12T12:45:51Z")

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Hello to all, I'm not able access node-red via browser due to my context storage error. Below error shown when running node-red from cli. "$ node-red start 10 Dec 15:04:53 - \[info\] Welcome to Node-RED 10 Dec 15:04:5…

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## [Manage message with many arduinos](https://discourse.nodered.org/t/manage-message-with-many-arduinos/55075)

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**Author:** [@azertym](https://discourse.nodered.org/u/azertym)\
**Replies:** 4\
**Last updated:** [12 December 2021 12:24 UTC](https://discourse.nodered.org/t/manage-message-with-many-arduinos/55075 "2021-12-12T12:24:49Z")

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Hi everybody, I'm come back to you again. To secure my project i want to manage my messages. I use 2 arduinos with different name 1=CAL, 2=BAL, On my sketch to send message by serial my messages start by CAL\* or BAL…

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## [Node-red-contrib-tcp-client how to stop communication](https://discourse.nodered.org/t/node-red-contrib-tcp-client-how-to-stop-communication/55015)

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**Author:** [@henkkas](https://discourse.nodered.org/u/henkkas)\
**Replies:** 8\
**Last updated:** [12 December 2021 10:30 UTC](https://discourse.nodered.org/t/node-red-contrib-tcp-client-how-to-stop-communication/55015 "2021-12-12T10:30:54Z")

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Hey guys, I have a tcp-client node working perfectly to receive messages from the smart meter. Now I want to be able to stop the communication. I tried several ways, but didn't succeed. Tried msg.enabled, msg.action a…

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## [Apache2 websocket](https://discourse.nodered.org/t/apache2-websocket/55047)

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**Author:** [@Laurijn](https://discourse.nodered.org/u/Laurijn)\
**Replies:** 4\
**Last updated:** [11 December 2021 17:58 UTC](https://discourse.nodered.org/t/apache2-websocket/55047 "2021-12-11T17:58:47Z")

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Hey im a hobbyist and try to make my own secure webinterface for my home automation im stuck at my proxy i use apache2 and i have nodered working with websocket but i cant get it to work with uibuilder this is what my…

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## [Using SHA or MD5 inside function-node](https://discourse.nodered.org/t/using-sha-or-md5-inside-function-node/55040)

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**Author:** [@hutje](https://discourse.nodered.org/u/hutje)\
**Replies:** 7\
**Last updated:** [11 December 2021 17:27 UTC](https://discourse.nodered.org/t/using-sha-or-md5-inside-function-node/55040 "2021-12-11T17:27:48Z")

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Is it possible to use the already existing crypto-js of Node-Red to use it inside the Function-node? Inside a for-loop I want to check if a part of a package is altered compared to my context-database. If so, I want to …

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## [QR-code scanner fails at second scan](https://discourse.nodered.org/t/qr-code-scanner-fails-at-second-scan/55037)

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**Author:** [@tbobek](https://discourse.nodered.org/u/tbobek)\
**Replies:** 6\
**Last updated:** [11 December 2021 15:42 UTC](https://discourse.nodered.org/t/qr-code-scanner-fails-at-second-scan/55037 "2021-12-11T15:42:16Z")

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The problem Currently I'm setting up a Node-red app to allow colleagues in the plant to scan three QR-codes from product, batch and template, check if the components fit together and send a feedback about the success of …

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## [Node-red-contrib-image-tools background color](https://discourse.nodered.org/t/node-red-contrib-image-tools-background-color/55034)

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**Author:** [@henkkas](https://discourse.nodered.org/u/henkkas)\
**Replies:** 2\
**Last updated:** [11 December 2021 12:09 UTC](https://discourse.nodered.org/t/node-red-contrib-image-tools-background-color/55034 "2021-12-11T12:09:07Z")

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I manage to generate a qr code, but don't seem to be able to change the background color (to white). Looked at all the examples, but don't get it right. Anybody can help me out here. \[{"id":"c7d344bb73c85014","type":"…

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## [I need to find a way to read a frequency of (on/off) on GPIO, Im trying to use TCS3200 colour sensor](https://discourse.nodered.org/t/i-need-to-find-a-way-to-read-a-frequency-of-on-off-on-gpio-im-trying-to-use-tcs3200-colour-sensor/55032)

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**Author:** [@XhanceHd](https://discourse.nodered.org/u/XhanceHd)\
**Replies:** 1\
**Last updated:** [11 December 2021 09:18 UTC](https://discourse.nodered.org/t/i-need-to-find-a-way-to-read-a-frequency-of-on-off-on-gpio-im-trying-to-use-tcs3200-colour-sensor/55032 "2021-12-11T09:18:50Z")

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I'm trying to run TCS3200 color sensor on raspberry pi 4 and node red. the color sensors outputs a frequency based on the light intensity I've tried running the normal GPIO In and removed the debounce, with a function …

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## [Enabling or disabling a node](https://discourse.nodered.org/t/enabling-or-disabling-a-node/54891)

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**Author:** [@rapidshe](https://discourse.nodered.org/u/rapidshe)\
**Replies:** 5\
**Last updated:** [11 December 2021 06:21 UTC](https://discourse.nodered.org/t/enabling-or-disabling-a-node/54891 "2021-12-11T06:21:20Z")

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Hello everybody! I need to automatically Enabling or disabling the nodes. I have found plugins "node-red-contrib-simple-gate" and "traffic node", but this is not what I want. I just need to disable and enable some the…

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## [Function-node freezes whole node-red](https://discourse.nodered.org/t/function-node-freezes-whole-node-red/55028)

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**Author:** [@hutje](https://discourse.nodered.org/u/hutje)\
**Replies:** 8\
**Last updated:** [10 December 2021 23:00 UTC](https://discourse.nodered.org/t/function-node-freezes-whole-node-red/55028 "2021-12-10T23:00:37Z")

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Hi I am currently working on a way to make a hex buffer out of various hex stings. A microcontroller (ESP32) will be using those hex values as values to compare an input with. I want to keep the message over MQTT as s…

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## [Disable flow / injection using a button on the dashboard](https://discourse.nodered.org/t/disable-flow-injection-using-a-button-on-the-dashboard/55006)

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**Author:** [@nosered1966](https://discourse.nodered.org/u/nosered1966)\
**Replies:** 14\
**Last updated:** [10 December 2021 19:56 UTC](https://discourse.nodered.org/t/disable-flow-injection-using-a-button-on-the-dashboard/55006 "2021-12-10T19:56:35Z")

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Hi all, I am totally new here and I am not really familiar with software development and things like this... I have created an example with a gauge on a dashboard feed with a random number activated using a inject node…

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## [(Asking) Any suggestions on a good JavaScript book to get](https://discourse.nodered.org/t/asking-any-suggestions-on-a-good-javascript-book-to-get/54908)

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**Author:** [@Trying\_to\_learn](https://discourse.nodered.org/u/Trying_to_learn)\
**Replies:** 6\
**Last updated:** [10 December 2021 19:46 UTC](https://discourse.nodered.org/t/asking-any-suggestions-on-a-good-javascript-book-to-get/54908 "2021-12-10T19:46:02Z")

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I was looking around for a book and found this list: If any of the regular people here who have dealt with me WRT JavaScript... Would any of these books be any good for me? The first one sounds good as it has short …

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## [Splitting an array of 7, and setting an topic for each message](https://discourse.nodered.org/t/splitting-an-array-of-7-and-setting-an-topic-for-each-message/54980)

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**Author:** [@monsivar](https://discourse.nodered.org/u/monsivar)\
**Replies:** 6\
**Last updated:** [10 December 2021 19:34 UTC](https://discourse.nodered.org/t/splitting-an-array-of-7-and-setting-an-topic-for-each-message/54980 "2021-12-10T19:34:43Z")

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Hi I got an function for splitting an array that contains last 7 days of data ( 0-6), where i want the data for the new day like this: for (let i = 0; i \< msg.payload.length; i++) { const el = msg.payload\[i\]; c…

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## [How to use array loop?](https://discourse.nodered.org/t/how-to-use-array-loop/54962)

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**Author:** [@Schmtterfliege](https://discourse.nodered.org/u/Schmtterfliege)\
**Replies:** 20\
**Last updated:** [10 December 2021 17:50 UTC](https://discourse.nodered.org/t/how-to-use-array-loop/54962 "2021-12-10T17:50:07Z")

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Hi, I'm pretty much a noob it seems. I can't get the array loop from contrib-loop-processing to work. My goal is to go over an array with 18 datapoints (as a string). Defined in a function node: I want to go over …

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## [Data entry into influxdb](https://discourse.nodered.org/t/data-entry-into-influxdb/52068)

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**Author:** [@Urs-Eppenberger](https://discourse.nodered.org/u/Urs-Eppenberger)\
**Replies:** 21\
**Last updated:** [10 December 2021 16:34 UTC](https://discourse.nodered.org/t/data-entry-into-influxdb/52068 "2021-12-10T16:34:16Z")

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Hello experts I'm using node-red to fetch sensor data from an MQTT broker. I modify the data and send it again to the broker, to the global context and some of it to influxdb. I use this data model on the broker: msg.…

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## [Installation of modbus](https://discourse.nodered.org/t/installation-of-modbus/55009)

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**Author:** [@pfe](https://discourse.nodered.org/u/pfe)\
**Replies:** 3\
**Last updated:** [10 December 2021 14:49 UTC](https://discourse.nodered.org/t/installation-of-modbus/55009 "2021-12-10T14:49:37Z")

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hello forum I have problem to install the node-red contrib modbus . Is there someone else who has the same problems ? How to solve ? my nodered is updated. I'm suspecting a problem with the serial link module.. Any adv…

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## [Out of memory crash on Windows 10 PC](https://discourse.nodered.org/t/out-of-memory-crash-on-windows-10-pc/54141)

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**Author:** [@thebaldgeek](https://discourse.nodered.org/u/thebaldgeek)\
**Replies:** 24\
**Last updated:** [10 December 2021 14:06 UTC](https://discourse.nodered.org/t/out-of-memory-crash-on-windows-10-pc/54141 "2021-12-10T14:06:01Z")

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I run Node-RED on a Windows 10 (Home) PC with 32 gigs of ram. Typically, the PC runs with around 9-10 gigs in use. I am running with Node.js version 14.18.1 and Node-RED version 2.1.3 For the past many years, the odd c…

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## [Lifespan markers worldmap](https://discourse.nodered.org/t/lifespan-markers-worldmap/54986)

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**Author:** [@Razio](https://discourse.nodered.org/u/Razio)\
**Replies:** 2\
**Last updated:** [10 December 2021 13:16 UTC](https://discourse.nodered.org/t/lifespan-markers-worldmap/54986 "2021-12-10T13:16:18Z")

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Hi, I noticed that the lifespan of the markers placed on worldmap is about 10 min. Is that predefined or is that caused by something specific? Node Red v2.1.4 node-red-contrib-web-worldmap v2.23.0 Thanks in advance. …

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## [How to use the node-red-contrib-firebase-admin package](https://discourse.nodered.org/t/how-to-use-the-node-red-contrib-firebase-admin-package/55011)

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**Author:** [@letandat1712](https://discourse.nodered.org/u/letandat1712)\
**Replies:** 0\
**Last updated:** [10 December 2021 13:06 UTC](https://discourse.nodered.org/t/how-to-use-the-node-red-contrib-firebase-admin-package/55011 "2021-12-10T13:06:55Z")

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Please help me, i use node-red-contrib-firebase-admin in order to read and write data to the firebase storage through node-red, i connected everything well done but the problem here is I do not know how to upload an imag…

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## [JSON to WLED2 node](https://discourse.nodered.org/t/json-to-wled2-node/54603)

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**Author:** [@hermann1514](https://discourse.nodered.org/u/hermann1514)\
**Replies:** 3\
**Last updated:** [10 December 2021 13:06 UTC](https://discourse.nodered.org/t/json-to-wled2-node/54603 "2021-12-10T13:06:17Z")

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Hi, can someone tell me, which format must have a json object to send it to a wled2 node to change the brightness or effects? Thx. Regards Hermann

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## [Memory spikes - no idea why](https://discourse.nodered.org/t/memory-spikes-no-idea-why/55000)

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**Author:** [@Razio](https://discourse.nodered.org/u/Razio)\
**Replies:** 3\
**Last updated:** [10 December 2021 11:49 UTC](https://discourse.nodered.org/t/memory-spikes-no-idea-why/55000 "2021-12-10T11:49:12Z")

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Hi again, A bit desperate on this one. I'm running several containers in BalenaOS (as project as (aged) student). The most important ones being node-RED and a postgresql db with postgis extension. I am loading a geojs…

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## [Display CPU Temp from Pi4 on localhost:1880](https://discourse.nodered.org/t/display-cpu-temp-from-pi4-on-localhost-1880/54989)

<div class="topic-metadata">

**Author:** [@Sol](https://discourse.nodered.org/u/Sol)\
**Replies:** 5\
**Last updated:** [10 December 2021 10:51 UTC](https://discourse.nodered.org/t/display-cpu-temp-from-pi4-on-localhost-1880/54989 "2021-12-10T10:51:49Z")

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I am new to Node-Red. Node-Red is installed on bullseye version of Raspberry. Started Node Red console on Pi4 and start localhost:1880 in browser. I create simple nodes that flow from "timestamp" into function node "ex…

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