Updating 2 Thingspeak Fields at the same time

Agent Code
1

I am new to the Imp, Squirrel, Thingspeak and electronics in general, but seem to be learning quicker than I thought.  Hopefully someone with more know-how can help me with my first Device-to-Agent-to-Thingspeak adventure.

I have created a two temperature sensor device that I plan to use Thingspeak to remotely monitor the two temperatures.  Currently I am able to poll the temperatures at the same time, log them etc.

When I get the data to the Agent and I attempt to post the values to Thingspeak it appears I am forced to split my posting into staggered posts due to the Thingspeak's posting limit (1-post per Thingspeak channel every 15 seconds).  That said, I got to playing with the Agent code, trying to create code that would re-combine my values into a single Thingspeak post.

So far, I have my two "device.on" functions as follows:

device.on("updateTemp2", function(Update_Temp2) {

    server.log("Update_Temp2 Value: " + Update_Temp2 + "*");

    });


device.on("updateTemp5", function(Update_Temp5) {

    server.log("Update_Temp5 Value: " + Update_Temp5 + "*");

    });

 

The server logs for these come out with the data I want, so I know things are working up to this point.  Now I need the code to combine the Update_Temp2 and the Update_Temp5 values for my Thingspeak post.  What I have so far is a 3rd “device.on function that I was hoping would receive the output from the two above device.on functions.

device.on("updateTemp", function (combined) {

    local request = http.post(thingspeakUrl, headers, ("field1"+"="+Update_Temp2+"&"+"field2"+"="+Update_Temp5));

    local response = request.sendsync();

    return response;

    server.log(response.body);

});

 

It seems I am struggling with the function scoping because my current error is as follows: ERROR: the index 'Update_Temp2' does not exist.  I have tried a handful of things but, I cannot seem to get the information to pass to my combined function.  I am sure there is a rookie mistake here, I just need someone to point it out.

Thanks,

2

If anyone else is having this problem, I was able to find my solution. I needed to convert this all to a single “agent.send” function on the device.nut and put the exact call information into the “object” location.

Device.nut code:
agent.send(“updateTemp”, (“field1”+"="+UpdateTemp2+"&"+“field2”+"="+UpdateTemp5));

Then in the Agent.nut:
device.on(“updateTemp”, function (post) {
local request = http.post(thingspeakUrl, headers, post);
local response = request.sendsync();
return response;
server.log(response.body);
});

Hope this may help someone else out there.

3

I am no Thingspeak expert but thought to comment to test my own knowledge.

I have managed to get data from agent to 2 Thingspeak channels before and to do this you need to set up and use 2 write API keys (1 per channel).

I believe the alternative, which I could not get to work correctly, is to set up 2 fields within a single channel. According to the Thingspeak Channel Settings page you can set up to 8 fields.

I too attempted to create a string as you have shown for “field1” and “field2” but only field1 data was shown on my chart. So you not alone in trying to solve this…

4

If you are updating two fields on the same ThingSpeak Channel. You need to enable each field on the Channel Settings screen. By default, field1 is checked / enabled.

5

I’m doing it, `local s = “field1=”+value1;+"&field2="+ value2+"&field3="+ value3+"&field4="+ value4 ;
server.log("what was sent: "+ s);
local response = httpPostToThingSpeak(s);

    imp.wakeup(60, SendtoThingSpeak); `

each minute, and it work for 24 to 48 h, and the thingspeak look to be receiving two post each time i send one, so the “response” of thingspeak to each of my subsequent post is like this

-0 // when thingspeak response 0, it mean there is an issue
-7611 // thingspeak response with the number of entry i’ve sent on that channel
-0 // thingspeak réponse is 0 again, but i’ve sent the same post than before
-7613 // strange, thingspeak response with 2 entry more than the last successful

anybody can help me?

6

G’day Johnygab.

I worked out how to do this on the weekend.

This code helped me get the IMP talk to ThingSpeak using a single data stream from the IMP and one field on ThingSpeak:
http://www.slickstreamer.info/2014/01/simpel-electric-imp-temperature-logger.html

Using the Channel Settings in ThingSpeak I added fields 2 and 3. I created an array of data on the IMP and sent it to the Agent, the Device code was as follows (not all the code but hopefully you get the gist):

local temp = sensor.getTemperature();
local rssi = imp.rssi();
local voltage = sendAnalogInput();
responsefromimp <- [temp, rssi, voltage];
agent.send("updateCharts", responsefromimp);

It is handled on the Agent as follows:

local field = “field1=”;
local field2 = “&field2=”;
local field3 = “&field3=”;
device.on(“updateCharts”, function(responsefromimp) {
local response = httpPostToThingspeak(
field + responsefromimp[0]
+ field2 + responsefromimp[1]
+ field3 + responsefromimp[2]);

Cheers,
Franc

7

your doing the same thing as me, and it will work, but after a few days, it won’t :stuck_out_tongue:

8

Hmmm, I haven’t had any trouble so far…