Unable to send and visualize data on my channel | ThingSpeak API | Forum

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Unable to send and visualize data on my channel
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January 29, 2020
9:42 am
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January 29, 2020
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I found simple example and tried to make it work. Based on what i see on serial monitor, code is working but the data are not visible on my channel.
If I go to https://api.thingspeak.com/update?api_key=XXXXXXXXXXXXXX&field7=1200 with my writing key, I can see that my entries increases.

Can someone help me, what could be the problem here?

Code is below:

#include "ThingSpeak.h"
byte mac[] = { 0xDE, 0xAD, 0xBE, 0xEF, 0xFE, 0xED};
EthernetClient client;
// On Arduino: 0 - 1023 maps to 0 - 5 volts
#define VOLTAGE_MAX 5.0
#define VOLTAGE_MAXCOUNTS 1023.0

unsigned long myChannelNumber = XXXXXX;
const char * myWriteAPIKey = "XXXXXXXXXXXXXXXX";

void setup()

void loop()
// int sensorValue = analogRead(A0);
int sensorValue = random(0,1023);
float voltage = sensorValue * (VOLTAGE_MAX / VOLTAGE_MAXCOUNTS);

// Write to ThingSpeak. There are up to 8 fields in a channel, allowing you to store up to 8 different
// pieces of information in a channel. Here, we write to field 1.
ThingSpeak.writeField(myChannelNumber, 1, voltage, myWriteAPIKey);
delay(20000); // ThingSpeak will only accept updates every 15 seconds.

February 4, 2020
3:56 pm

Forum Posts: 885
Member Since:
March 7, 2017
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Do you have all the fields enabled for your channel? I see your test write is to field 7, but in the code you write to field 1. If you read back the data, do you see any null entries?

FYI, MATLAB answers is now the preferred location for ThingSpeak Community support.

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