Raspberry Pi - MQTT Publish & MQTT Subscribe- Updating Multiple Fields In one MQTT publish request and vice versa

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I am working on raspberry pi with MQTT publish block. It is being used with Thingspeak Platform. I understood the example models for publiash and subscribe the fields.
I want to use the MQTT publish and Subscribe block for multiple fields of channel. I am struggling with proper Topic argument for both publish and subscribe blocks.
As I am bengineer, I will be happy to further explain the problem statement if the info given is insufficient.
I used floowing links as refernece but not understood the specific argument.
VISHAL SAWANT on 6 May 2021
Thanks for replying. I tried this combination with MQTT publish block. The entry counter is updating but the values are not visible on Channel Field charts.
Input is 1x8 array of uint8 data type.

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Answers (1)

Christopher Stapels
Christopher Stapels on 6 May 2021
Your message needs to be of the form 'field1=value&field2=value2' etc.
If you use the update single field topic instead of the multiple fields topic, you can just send a number.
Christopher Stapels
Christopher Stapels on 17 May 2021
Edited: Christopher Stapels on 17 May 2021
If you dont need MQTT, you can use the ThingSpeak blocks in the support package for Raspberry pi. This has blocks for the ThingSpeak REST API.
If you want to update miltiple fields in one call, I think the MQTT block will not work for you. Ill submit it as an enhancement request for the block.

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