How many fields of a channel can I update at the same time with a free license?

Hi everyone,

can you tell me how many fields of a single channel can I update with a single command, with a free thingspeak license?

I know that I can create a maximum of 4 channels, each one with 8 fields, but I can't update more than 4 fields. I selected 5 fields and I sent a single string with the 5 values to update, but no data was shown; conversely, if i send a string with 4 fields to update (or 3 fields + the status), it works.

I posted the code that i used with the 'GET' command; as long as I try to update 4 (or less) fields it always works without issues. So I would like to know if I need to purchase a license in order to use more than 4 fields of a channel, and if the student license would be fine.

Thank you

// data string to send to ThingSpeak

String data="GET https://api.thingspeak.com/update?api_key=" + wKey + "&field1=" + String(PM1,2) +"&field2=" + String(PM25,2) + "&field3=" + String(PM10,2) + "&field4=" + String(H,2) + "&field5=" + String(T,2);

// + "&status=" + String("status");

SIM.println("AT+CIPSEND"); //begin send data to remote server

delay(4000);

SIM.println(data); // send data to remote server

delay(4000);

SIM.println((char)26);

[Christopher Stapels]

What hardware are you using? There may be memory limitations.

In my experience, most cases where AT commands fail are due to the size of the string that is calulated. Are you calculationg the size of the string anywhere? I thought you have to tell the number of characters to send?

You can update all eight fields, and the three location fields and the status field in a single post, even with a free licene.

There are good write examples (even for AT commands) in the ThingSpeak library.

[Carlo]

Thank you for the reply.

I'm employing arduino (uno or mkr zero) with an adafruit fona 800 shield; I didn't calculate the size of the string to send to thingspeak anywhere in the code.

I did some tests and you are right, my problem is the memory limitation; I tried to delete some global variables and now all the five fields I need are correctly updated.

Thank you a lot again