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I wanted to ask of 3M messages of thingspeak free account will renew every year? Thank You

Hi, How can I draw windrose on matlab,I have attached sample data for you, sorry for the inconvenience

Hello, I am currently working on a simple android app for a smart irrigation system. Basically the app lets the user enter the name of the plant and then lists all the plants of the garden. Then, I have divided plants into three categories depending on their watering needs and I have created three int values for the amount of plants per group. Essentially I want to send these three values to a thingspeak channel I created, to 3 separated fields. I am not familiar at all with server programming in Java so I would really appreciate any kind of help in how to do this.

Can not pick just a single field for "No data check", just the whole channel. Is there any way to change?

I have a personal account which I use for my home projects, along with a paid license which I use for monitoring a set of sensors in a remote building.

All my sensors went offline at about the same time, but I am only just noticing this now, because I have been focused on why the remote location went offline, thinking that it was an issue with the internet or WiFi at that location, rather than a problem with posting the data!

All my monitoring setups are using electricImp devices to post data to ThinkSpeak and have been in some cases, running for several years without any issues. All the devices are now returning a 400 - invalid constant string error.

See logs below.

|2022-04-19T13:30:07.017 +00:00	[Agent]	https://api.thingspeak.com/update?api_key=XXXXXXX&status=OK&created_at=2022-04-19 13:30:01 UTC&field4=0.00&field3=0.00&field6=0.00&field5=0.00&field2=14.65&field1=2022-04-19%2013%3A30%3A01%20UTC&status=OK&field8=0.6129&field7=0.00&created_at=2022-04-19%2013%3A30%3A01%20UTC
    2022-04-19T13:30:07.086 +00:00	[Agent]	PUSH: 400 - invalid constant string

I modified a device to not send the date in field 1 on one device because I thought that might be causing the problem, but it is not clear to me what changed. I have been sending data like this for a long time.

Any ideas appreciated.

Thanks

Hi... I managed to work out both the pub & sub parts of MQTT with my esp8266. I did the example from over here ... and all works fine. The publishing happens every 15secs... and it received the published values back almost immediately. see Img1.png

Now using flutter from my mobile app I did the same thing... and I was able to pub & sub... and also checked the Field1 values in my Thingspeak account that i am writing to and reading as an MQTTclient. It all works correctly.

HOWEVER... heres the problem================ When I only publish from the mobile a value for Field1. And subscribing at the same time from my esp8266 to receive the updated value of Field1... something weird happens... My Field1 in the channel, in my Thingspeak account has been updated correctly... but my esp8266 doesnt receive the updated value. INSTEAD, at the same time I can see in the serial monitor logs, the esp8266 reconnects back to our MQTT server!! No update was received. It felt as if everytime I published a value from my mobile, it made my esp8266 disconnect and hence it needed to reconnect to the MQTT server. i checked this 10 times and it happened without a coincidence. I ran the same code on the esp8266, except that I never let it publish every 15secs. So all it did was stay subscribed and await an update from my mobile app. please see img2.png

and this is the flutters connection code

 client.logging(on: false);
    client.setProtocolV311();
    client.keepAlivePeriod = 10;
    client.onDisconnected = onDisconnected;  //....callbacks
    client.onConnected = onConnected;  //....callbacks
    client.pongCallback = pong;  //....callbacks

    final connMess = MqttConnectMessage()
        .withClientIdentifier('xxxxxxxxxxxxxxxx')
        .withWillTopic('willtopic') // If you set this you must set a will message
        .withWillMessage('My Will message')
        .startClean() // Non persistent session for testing
        .authenticateAs('xxxxxxxxxxxxxxxx', 'aaaaaaaaaaaa')
        .withWillQos(MqttQos.atMostOnce); // means = 0
    print('client connecting....');

Any help will be appreciated. Just wanted to iterate that individually they both work fine. Just that i need the updated value... and i dont receive it. Any ideas?? thanks, YOhan

Hi! As the title says, I want to group the data readings from multiple fields and channels into a single formatted tweet. Kinda of like a status report tweet for a few different sensors I have running. Is this possible? My current understanding of the MATLAB analysis/react is that it can only do 1 field at most. Any help would be greatly appreciated by this stresses out college senior :)

I have a Thingtweet: "Measurements %%datetime%% Comment" The tweet will send the time as say: 5:23pm I want it in 24hr format = 17:23 I have scoured the site and I cant find any way of doing this in a tweet. Also that would be local time, is it possible to use UTC ?



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