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I am collecting Data at 1 minute intervals using esp8266, the data is then sent to Thingspeak on the minute intervals. However I would like to store the data collection on the esp Ram. I am using batteries to power the circuits , if I can store the data and send it on demand I can save quite a bit of battery energy (used up by wifi) - (I already use sleep mode between intervals).  As well as using Thingspeak to visuliase the data, I also use a third part app called Thingview which 'feeds' off thingspeak. I am looking for a way to trigger the 'data send' upon opening thinkspeak chanel,so rather than sending every minute it might need to be accessed two or three times a day,  is this possible?
Thanks Edward
Hi!
I can't see my data in the charts. I'm using arduino wifi and the connection works. 
Maybe I did something wrong in this options

Is there a way to get a handle or link to the database each time I do a WRITE or group of WRITEs? I need to access the set of records that comprises a user session, which could be many WRITEs. My impression is that Thingspeak appears as a continuous stream with no way to mark a set of WRITEs as a group or session. Methods I have tried like retrieval (READs) using timestamps and other after-the-fact queries are not very accurate or user friendly. Thanks.
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we are planning to design a drive for an EV using synchronous reluctance motor. To move further we need some drive circuits for simulating and comparing various motors with synchronous reluctance to justify our literature survey. can we get som circuit suggestions?
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    I am running the code from the following URL: https://kr.mathworks.com/help/comm/ref/comm.ricianchannel-system-object.html. I copied and executed the example to visualize the channel's impulse response. However, when I run the same code multiple times with the same path gains and delays, I get different impulse response results each time. What could be the reason for this?
This behavior is unexpected because the code and settings are the same for each run, and the impulse response should remain constant.
This is the code.
fs = 3.84e6;                                  % Sample rate in Hz
pathDelays = [0 200 800 1200 2300 3700]*1e-9; % in seconds
avgPathGains = [0 -0.9 -4.9 -8 -7.8 -23.9];   % dB
kfact = 10;                                   % Rician K-factor
fD = 50;                                      % Max Doppler shift in Hz
ricianChan = comm.RicianChannel( ...
    SampleRate=fs, ...
    PathDelays=pathDelays, ...
    AveragePathGains=avgPathGains, ...
    KFactor=kfact, ...
    MaximumDopplerShift=fD, ....
    Visualization='Impulse and frequency responses');
ricianChan(0.1);
The two images below show the results of running the same code.
 
  
Hi, 
I was wondering if anyone could help me with how I can simplify this part of my script, specifically scenario 1-3, so that it is easier to read. Perhaps with functions etc. (the comments are in swedish sorry heh. But the script works). 
Thanks in advance!
F1_batt_till_P19 = zeros(8760,length(Effekt)); % det som batteriet laddar upp fastigheten med
F1_Elkons_batt = zeros(8760,length(Effekt)); % konsumtionen från nätet av batteriet 
F1_batterilast_tot = zeros(8760,length(Effekt)); % batterilasten lagras kontenueligt. 
F1_elkonsum = [];
for k = 1: length(Effekt) % går igenom alla olika effekter mellan 100 - 1000 kW
   F1_last_batt = 0; % batteriet måste nollas efter varje ny effekt. 
   batterikapacitet = Kapacitet(k); % såhär stort är batteriet beroende på effekten. Beror på C rate (blir dubbelt så stort som effekten). 
   batterikapacitet_min = batterikapacitet * SOC_low/100; % undre gräns 
   batterikapacitet_max = batterikapacitet *SOC_high/100; % övre gräns   
   F1_last_batt = batterikapacitet_min; % hur mycket kapacitet har batteriet. Finns det något . Börjar tomt. 
   for i = 1:12 % gå igenom månaderna
       mon = [31,28,31,30,31,30,31,31,30,31,30,31];
       slut = mon(i)*24;
       % medelkonsumtionen (i kW) per månad Elkons_months_eft(744,12)
       medel_kons = mean(Elkons_months_eft(1:slut, i)); % Månadens medelkonsumtion
       for m = 1:slut % gå igenom timmarna per månad
           % går igenom varje timme (m), för varje månad (i). 
           % scenario 1 - batteriet laddar ur till medelvärdet
           if Elkons_months_eft(m,i) > medel_kons 
               topp = Elkons_months_eft(m,i) - medel_kons; % storleken på toppen över medelvärde
               % Om batteriet inte är tomt från början. Om det kan laddas ur. 
               if F1_last_batt > batterikapacitet_min
                   % Om batteriet kan laddas ur med hela efffekten utan att gå under min
                   if (F1_last_batt - Effekt(k)) >= batterikapacitet_min 
                      % Om toppen är större eller lika med än vad som får kapas med batteriet - hela effekten används.  
                      if topp >= Effekt(k) % A 
                           F1_batt_till_P19( (24*sum(mon(1:i-1)) + m) ,k) = Effekt(k); % effekt under timmen som batteriet tillgodoser till Pyramiden 19
                           F1_last_batt = F1_last_batt - Effekt(k); % batteriet laddas ur med hela effekten den timmen
                      % Om toppen inte är större än effekten - hela toppen kapas. 
                      else % B 
                           F1_batt_till_P19((24*sum(mon(1:i-1)) + m) ,k) = topp; 
                           F1_last_batt = F1_last_batt - topp; 
                      end
                   % Om batteriet inte kan tömmas med hela effekten.    
                   else 
                       liten_effekt = F1_last_batt - batterikapacitet_min; % mängden som kan laddas ur. 
                       % Om toppen är större än det vi kan använda – allt som är kvar används
                       if topp >= liten_effekt % C
                           F1_batt_till_P19((24*sum(mon(1:i-1)) + m) , k) = liten_effekt; % effekt under timmen som batteriet tillgodoser till Pyramiden 19
                           F1_last_batt = F1_last_batt - liten_effekt; % batteriet laddas ur till min 
                       % Om toppen inte är större än det vi kan använda - hela toppen kapas    
                       else % D 
                           F1_batt_till_P19( (24*sum(mon(1:i-1)) + m) ,k) = topp; 
                           F1_last_batt = F1_last_batt - topp; 
                       end
                   end
               end  
            % scenario 2 - batteriet laddar upp och tar från nätet 
           elseif Elkons_months_eft(m,i) < medel_kons 
               % Om batteriet inte är fullt
               if F1_last_batt < batterikapacitet_max 
                   % Om det får plats en laddning av hela effekten – Batteriet laddas upp
                   if (F1_last_batt + Effekt(k)) <= batterikapacitet_max 
                       % Om uppladdningen inte överstiger medelvärdet – Batteriet laddas upp med effekten
                       if (Elkons_months_eft(m,i) + Effekt(k)) <= medel_kons  % A 
                           F1_Elkons_batt((24*sum(mon(1:i-1)) + m),k) = Effekt(k); % mängden som tas från nätet
                           F1_last_batt = F1_last_batt + Effekt(k);  
                       % Om uppladdningen överstiger medelvärdet – Batteriet laddas upp med det som går    
                       else % B
                           till_medel = medel_kons - Elkons_months_eft(m,i);
                           F1_Elkons_batt((24*sum(mon(1:i-1)) + m),k) = till_medel; 
                           F1_last_batt = F1_last_batt + till_medel; 
                       end  
                   % Om det får plats mindre än hela efffekten i en laddning – Batteriet laddas fullt     
                   else 
                       plats = batterikapacitet_max - F1_last_batt; % det som får plats i batteriet 
                       % Om elkonsumtionen ej överstiger medelvärdet – Batteriet laddas upp till max-taket
                       if (Elkons_months_eft(m,i) + plats) <= medel_kons % C
                           F1_Elkons_batt((24*sum(mon(1:i-1)) + m),k) = plats; 
                           F1_last_batt = F1_last_batt + plats;  
                       % Om elkonsumtionen överstiger medelvärdet – Batteriet laddas upp med det som går     
                       else % D
                           till_medel = medel_kons - Elkons_months_eft(m,i);
                           F1_Elkons_batt((24*sum(mon(1:i-1)) + m),k) = till_medel; 
                           F1_last_batt = F1_last_batt + till_medel; 
                       end 
                   end 
               end
           % scenario 3 - om inget händer 
           elseif Elkons_months_eft(m,i) == medel_kons 
               % inget händer. Precis som jag vill ha det. 
           end
       F1_batterilast_tot((24*sum(mon(1:i-1)) + m),k) = F1_last_batt;  % lägger in batterilasten för timmen i en lista. 
       end % slut - for timmar per mån (m)
   end %slut  for - månaderna (i) 
  % tar bort den sista uppladdningen av batteriet så det kommer ner till min värdet iaf
% får ta bort min värdet kostnaden sen manuellt. 
   for p = 0:(8760-1)
       % Om batteriet har laddning över min kvar i slutet
       if F1_last_batt > batterikapacitet_min
           over = F1_last_batt - batterikapacitet_min;
           % Om platsen är större än eller lika med laddningen på batteriet – Batteriet töms ner till min 
           if F1_Elkons_batt(end-p,k) >= over
               F1_Elkons_batt(end-p,k) = F1_Elkons_batt(end-p,k) - over;
               F1_last_batt = batterikapacitet_min;
               F1_batterilast_tot(end-p,k) = batterikapacitet_min;
           % Om platsen är mindre än laddningen på batteriet – Batteriet töms med hela platsen
           elseif F1_Elkons_batt(end-p,k) < over
               F1_last_batt = F1_last_batt - F1_Elkons_batt(end-p,k);
               F1_batterilast_tot(end-p,k) = batterikapacitet_min;
               F1_Elkons_batt(end-p,k) = 0;
           end
       end
   end                
end % slut for - effekt (k)
% summerar ihop året till ett värde. Får ett värde för varje effekt. 
F1_elkonsum_sum =[];
F1_batt_till_P19_sum =[];
F1_Elkons_batt_sum = [];
F1_effekttopp_medel_year = []; % medel effekttopp under året 
for v = 1:length(Effekt)
    F1_elkonsum(:,v) = (Elkonsumtion_eft(:,1) - F1_batt_till_P19(:,v)) + F1_Elkons_batt(:,v); % elnätskonsumtion under året
    F1_elkonsum_sum(v) = sum(F1_elkonsum(:,v));
    F1_batt_till_P19_sum(v) = sum(F1_batt_till_P19(:,v));
    F1_Elkons_batt_sum(v) = sum(F1_Elkons_batt(:,v));
end
% figure; yyaxis right; plot(F1_elkonsum(:,20)); 
% hold on; plot(Elkonsumtion_eft(:,1));
% hold on; yyaxis left; plot(F1_batterilast_tot(:,20)); legend('Konsum','ladd');
% Beräknar maxeffekten (toppen) för varje månad för alla effekter. Blir  en 12 x length(effekt) lista 
% Den går per rad och tar maxeffekten för månaden för alla kolumner = för alla olika effekter. 
F1_effekttopp_months = zeros(12,length(Effekt)); % effekttopp under månaden för alla olika effekter. 
mon = [31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31]; 
for b = 1:12
    F1_effekttopp_months(b,:) = max(F1_elkonsum( (24*sum(mon(1:b-1)) + 1) : 24*sum(mon(1:b)) , : ) ); % [kW]
end
% beräknar medeleffekten för året
for v = 1:length(Effekt)
    F1_effekttopp_medel_year(v) = mean(F1_effekttopp_months(:,v));
end 
Hi, I'm losing comms with thingspeak after exactly one hour. I'm on the free plan while I evaluate TS.
I am sending data once a minute. It works fine for one hour, and I get 200-OK responses. After exactly 1 hour, the response from TS is a 404-not found. I do a new DNS lookup, and get a new IP address for TS. Still no response. I do more DNS lookups, and get another different IP address.  It cycles through 3 different IP addresses, but noe of them work one hour after bootup on my device.
I'm running an Arduino Nano with an Ethercard and the JNH library. I can still ping the arduino, serve webpages and ping a monitored device, and get NTP time, all in a 1 minute loop, so I doubt the TCP/IP stack has crashed.
after I restart the device, it works again for exactly one hour, and the I lose comms with Thingspeak again.
Any help would be appreciated!
Thanks,
Adrian
In my struggle to get my SIM7600 connected to thingspeak using MQTT, i went to the basics: simple testing of my connection:
I use this site : https://testclient-cloud.mqtt.cool
Protocol :tcp
Host : mqtt3.thingspeak.com
Port : 1883
Username : got it from my device (double checked !)
Password : got it from my device (double checked !)
When i try to connect I get the message Connection refused : bad user name or password.
I am completely lost. What basic stupi mistake am i missing. I thoroughly read the MQTT help pages.
Any help is appreciated.
Update :
When i select Dedicated connection and i also fill in the will message and will topic, i am able to update my channel. At least some progress. 
my Channel ID 2305210 and Channel ID 2300906 are not working properly. Pl.Guide me 
Hi there,
I hope someone can help me on this.
I have written a code to connect my SIM7600 to Thingspeak using MQTT. It is basically an aruidino code. All instructions are echo's with an OK message so assume those instrictions are correct. However, the final step, publishing the message to the MQTT server return an error : CMQTTCONNLOST : 0,1. 
Any idea which instructions might be wron?
I included the commands send.
10:09:09.031 -> AT+CMQTTPUB=0,0,60,0,0
10:09:09.031 -> +CMQTTPUB: 0,0
10:09:09.031 -> 
10:09:09.031 -> OK
10:09:09.031 -> 
10:09:09.031 -> +CMQTTCONNLOST: 0,1
The program :
SerialAT.begin(115200, SERIAL_8N1, RXD2, TXD2);
delay(1000);
SerialAT.println("AT+CRESET"); // Reset the SIM7600 module
Read_Response(30000);
SerialAT.println("AT+IPR=115200");  // Set Baudrate of the SIM7600 module
Read_Response(30000);
SerialAT.println("AT+CSQ");  // Check signal level
Read_Response(10000);
SerialAT.println("AT+COPS?");  // Query network information
Read_Response(10000);
SerialAT.println("AT+CMQTTSTOP"); //Stop MQTT service
Read_Response(10000);
SerialAT.println("AT+CMQTTSTART"); //Start MQTT service
Read_Response(10000);
SerialAT.println("AT+CSSLCFG=\"sslversion\",0,3"); //Configure SSL contect ssl_ctxindex,sslversion <0,TLS1.2>
Read_Response(10000);
SerialAT.println("AT+CSSLCFG=\"authmode\",0,0"); //Establishing MQTT Connection <ssl_ctx_index,authmode<0,no autentification>
Read_Response(10000);
SerialAT.println("AT+CMQTTACCQ=0,\"Username\",0,4"); // Acquire a client <client_index,client_ID>
Read_Response(10000);
SerialAT.println("AT+CMQTTSSLCFG=0,0"); // Set the SSL context <session_id,ssl_ctx_index>  ssl_ctx_index check AT+CSSLCFG command
Read_Response(10000);
SerialAT.println("AT+CMQTTCONNECT=0,\"tcp://mqtt3.thingspeak.com:1883\",90,1,\"Username\",\"password\""); //Connect to MQTT server <client_index,server_addr,keep_alive time,clean_session,username,password>
Read_Response_Ignore_OK(3000);
String payload="\"channels/"+ String(ChannelId)+"/publish\"";
int Payload_Length;
Payload_Length=payload.length();
SerialAT.println("AT+CMQTTTOPIC=0,"+String(Payload_Length)); // Input the publish message topic <client_index,req_length>
SerialAT.println(payload);
Read_Response_Ignore_OK(3000);
payload="field1=12&field2=13&status=MQTTPUBLISH";
Payload_Length=payload.length();
SerialAT.println("AT+CMQTTPAYLOAD=0,"+String(Payload_Length)); // input the publish message body <client_index,req_length>
SerialAT.println(payload);
Read_Response_Ignore_OK(1000);
SerialAT.println("AT+CMQTTPUB=0,0,60,0,0"); // Publish a message to the server <client_id,qos,pub_timeout,retained>
Read_Response_Ignore_OK(1000);
Serial.print(Receive_buffer);
Serial.println("And we are done");
Adam and Heather will be discussing new features in R2023b and answering your questions in a few hours - visit the link below to check out the preview and sign up for notification. 
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I wanted to write to my public channel 2278931 with 8 different values to 8 different gauge widgets.
Here is my link.
https://api.thingspeak.com/update.json?api_key=xxxxxxxxxxxxxxxx&field1=1&field2=2&field3=3&field4=4&field5=5&field6=6&field7=7&field8=8
You can change values and in the link to change gauge values. On edit I edited my write key to make it not work for others but it will work with your own key.













