ESP8266-12 blynk wireless temperature LM35 sensor

in this project using a esp8266, to show the temperature LM35 sensor on your smartphone or tablet.

if you have available sensors DHT11 DHT22 or you can use the following Instructable

DHT11 sensor

ESP8266-12 blynk wireless temperature, humidity DHT 11 sensor

DHT22 sensor

ESP8266-12 blynk wireless temperature, humidity DHT22 sensor

Step 1: Materials

ESP8266-12 (esp8266-7, ...... , esp8266-12e)

LM35 temperature sensor (10mv /°c)

power regulator 3,3v-5v

Step 2: Connections


VCC +3,3v

CH-PD +3.3v

ADC ---- pin2 (LM35)

GND ground

GPIO5 ground


LM35 sensor

pin 1 +3,3v

pin 2 output .---- ADC (ESP8266-12)

pin 3 ground


Step 3: Blynk App



store app

Blynk Apple Store

Blynk Google Play store


configure blynk

create new project ( use hardware model esp8266 )

generate AUTH TOKEN

send E-mail TOKEN ( copy TOKEN in the esp8266 sketch)

in the app Blynk use Value Display widget or Gauge widget

Step 4: Sketch


blynk library
SimpleTimer library


to programming the ESP8266-12, I use ide arduino 1.6.5 and CP2102 3.3V USB To UART Serial Interface Module Adaptor ( do not connect the power of the CP2102 to esp8266-12).


SP8266 sketch

change the sketch in the following lines with your data

char auth[] = "xxxxxxxxxx"; //insert here your token generated by Blynk

Blynk.begin(auth, "ssid", "password!"); //insert here your SSID and password



If you use ide arduino ADC ---- pin 17

range voltage 0-1.0v

range units 0-1024

Step 5: Thanks

thanks by catoplepa

<p>Nice one! Do you have any idea about how much power it consumes? From my understanding the ESP 12 shouldn't go above 200mA, but the ESP-01 has peeks over 300mA... and my batteries goes crazy in transmissions :(</p><p><a href="https://plus.google.com/107944587749396190662/posts/5oo987tnB54" rel="nofollow">Other wireless temperature example</a></p>
<p>My values are out of whack when I use the equation 1/1024 * 100. At 19 deg c, I get values around 12.00 for the temperature and around 125 for the analogRead on the tempPin.</p><p>The sensor works properly without the ESP on an Arduino.</p><p>Any ideas what might be causing this?</p>
<p>Just some details.</p><p>The output voltage from the sensor seems to be right (~190mV at 19 deg C). However, when I measure the voltage from ADC pin to GND pin on the ESP-12F, it's around 130mV (also indicated by the analogRead function)-- which seems a bit far from the 1V-1024 conversion.</p>
<p>For some reason, 1.5V instead of 1V seems to be an appropriate conversion in my case but I have no idea why -- I know that ADC pin goes from 0 to 1V (or should at least). </p>
<p>Hi you wrote GPIO5 to GND but on the pic GPIO15 is grounded?</p>
please make one with ds18b20 sensor on a digital pin.!!
<p>Hello all, problem solved.</p><p>It seems that it is very important to place home made functions in front of <br>void setup() and<br>void loop()</p>
<p>I have a problem at compile time!</p><p>&quot;error: 'sendUptime' was not declared in this scope&quot;</p>
<p>Hi, I have the same problem. You already have a solution?</p>
<p>Hi, I have the same problem. How do you have resolve it ?</p>
<p>Hi, kyuubi87</p><p>Please check that you have library SimpleTimer in the folder</p><p>Thanks</p>
<p>Hi, clebrw</p><p>Please check that you have library SimpleTimer in the folder</p><p>Thanks</p>
<p>I have the same problem at compile</p><p>&quot;error: 'sendUptime' was not declared in this scope&quot;</p><p>i have everything in same folder :-(</p>
<p>Farenheit = (Celsius*1.8)+32</p>
<p>Yeah, it works. thank you catoplepa.</p><p>What i have to change in the code to get Celsius and not Farenheit?</p>
<p>OK thank's</p><p>I wish there was a sketch for DS18B20.</p><p>I'll be waiting I believe will be written.</p>
<p>Hi Homerruma</p><p>not because the two sensors are completely different, LM35 is an analog sensor while DS18b20 is a digital sensor.</p><p>the DS18b20 is certainly compatible with both Blynk that ESP8266 but that created a new sketch</p>
<p>Hello</p><p>Is it possible to replace the LM35 sensor with DS18B20?</p>
<p>I'm sorry but I do not know what it means</p>
<p>Hello,</p><p>When I try to load the sketch, after a few seconds, the message appears.</p><p>I use a 3.3V 3A capable.</p><p>I tried many baud rates...</p><p>But I finally I found that the module is in 74880 bauds! Yes 74880.</p><p>When I power it I receive these 2 lines : </p><blockquote>ets Jan 8 2013,rst cause:1, boot mode:(7,3)<br><br>waiting for host</blockquote><p>But there is no 74880 baud rate in arduino IDE.</p><p>Any idea of what does this message means?</p><p>Thanks a lot.</p>
<p>Hi, whogarden</p><p>It happens while loading the sketch or after?</p><p>you can try to put the Baud rate 9600</p><p>Also check, that you have sufficient power (3.3 V). <br>RX&lt;-&gt;TX<br>TX&lt;-&gt;RX</p><p>and check your wiring</p>
<p>Hello,</p><p>With the sketch below, I have the error :</p><p>warning: espcomm_sync failed<br>error: espcomm_open failed</p><p>And no answer to AT command.</p><p>Any idea about baud rate?</p><p>Something else?</p><p>Thanks.</p>
<p><font><font><font><font>try to load this sketch </font></font></font></font></p><p><font><font></font></font><font style=""><font><a href="http://docs.blynk.cc/#hardware-set-ups-esp8266-standalone" style="">http://docs.blynk.cc/#hardware-set-ups-esp8266-standalone</a></font></font></p><p><font style=""><font><font>Or test At comand </font></font></font></p><p><font><font><a href="http://forum.hobbycomponents.com/viewtopic.php?f=74&t=1777">http://forum.hobbycomponents.com/viewtopic.php?f=74&amp;t=1777</a></font></font></p><p><font><font><font>....Catopl</font></font></font></p><p><font style=""><font><font><br></font></font></font></p>
<p>Thank you for these very good explanations..</p><p>but many hours later, ... nothing.</p><p>I have no answer of the esp. (I done every thing like it is described). I have only the blue red lit.</p><p>No AT dialog and no AP MAC with Nodemcu firmware programmer (from 9600 to 115200 baud tested).</p><p>Does the esp send any character(s) when powered?</p><p>Thank for your help.</p>
<p>use this tutorial </p><p><a href="https://www.instructables.com/id/Getting-Started-with-the-ESP8266-ESP-12/">https://www.instructables.com/id/Getting-Started-wi...</a></p><p><a href="https://www.instructables.com/id/ESP8266-ESP-12Standalone-Blynk-101/">https://www.instructables.com/id/ESP8266-ESP-12Stan...</a></p><p><img class="IblesFileThumbnail" src="https://www.instructables.com/files/deriv/F1R/RWME/IG2JI4WC/F1RRWMEIG2JI4WC.SQUARE3.jpg"></p><img class="IblesFileThumbnailExpanded" src="https://www.instructables.com/files/deriv/FOD/JO6Q/IG2JI6DY/FODJO6QIG2JI6DY.SQUARE3.jpg" style="top: 0.0px;left: 0.0px;">
<p>Hello,</p><p>because I am very new with esp8266, can you explain in details what to do.</p><p>you say &quot;to programming the ESP8266-12,..&quot; </p><p>what are connections to do with the usb to uart converter?</p><p>Is the programm writen inside the esp by the IDE Arduino?</p><p>Thank you.</p>

About This Instructable




More by catoplepa:ESP8266-12 blynk wireless simple virtual led ESP8266-12 blynk wireless temperature LM35 sensor ESP8266-12 blynk wireless temperature, humidity DHT22 sensor 
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