Wednesday, September 9, 2015

Stream IoT sensor data ESP8266 NodeMCU v1.0 ESP12-E with Arduino IDE

Stream IoT sensor data ESP8266 NodeMCU v1.0 ESP12-E with Arduino IDE
Streaming sensor data using ESP8266 NodeMCU v1.0 ESP12-E with Arduino IDE to Thingspeak

Sorry for the long hiatus, yours truly was busy trying to put bacon on the table, and also playing catch-up with the increasing rent.

Back in late 2014 and early 2015, your truly came across this nifty WiFi Chip ESP8266 (the ESP-01) and have to battle among the inconsistent documentations from various sources. For the spur moment, he documented his frustrations (findings) as an instruction guide ESP8266 guide or on instructables ESP8266 guide . In due course, the ESP8266 WiFi has opened a whole new window of opportunity for him and his padawans.

The caveat at the moment of writing in 2014/2015 was to find a way to eliminate the “middle” MCU, the well-loved Arduino Uno (or Arduino Mega). It doesn’t make sense to forgo the ESP8266 that sports a 32bit CPU by using an Arduino Uno that sports an 8bit CPU for computations. Over the several months of dec14 to sept15, several IDE flavours/methodologies was released on the Internet to use standalone ESP8266, e.g to use ESP8266 and the available IO pins sans the Arduino Uno or Arduino Mega. From retrospective view, the cost of deploying an IoT framework to collect data has gone down drastically with just the standalone ESP8266 alone as the sentinel device.  The flavours of standalone mode are ESP8266 Lua, and ESP8266 Arduino IDE. Check out the reference section for details.

After two Maker Faires (Maker Faire Singapore, and Maker Faire Shenzhen), one Tan Kah Kee Young Inventors Award which students won a Merit Award, one SUTD Design & Technology Contest which students won third prize and merit prize, one IDC Robocon which students represented Singapore, one IEEE AIYEHUM 2015 which student shortlisted as finalist, and countless submissions later; the hiatus is over. In Maker Faire Shenzhen, yours truly rub shoulders with several big names in the industry; perhaps the mostly-male playing field (for the record there were females; @juliewatai @sexycyborg, etc were surrounded by hordes of testosterone raging males armed with cameras of various sizes firing away, while your truly observe with amusement from afar) and the maker-ish aura projected by yours truly. One of them was Zhao Zong (赵总) of AI Thinker, the manufacturer of NodeMCU (a breakout version of the ESP8266 ESP12-E and CP2102, with out of the box support for LUA). Yours truly landed his salty porky hands on a bunch of NodeMCU v1.0 at very competitive price (友情价).

In this write up, yours truly is introducing the use of NodeMCU v1.0 (black) with ESP8266 Arduino IDE 1.6.5. There are lots of write up on the NodeMCU v0.9 or ESP8266 ESP-01 and variants with LUA, but information is scarce for NodeMCU v1.0 and ESP8266 Arduino IDE. This post is also a superseding update of an earlier how-to post of using ESP8266 ESP-01 with Arduino Mega and the temperature data is streamed to thingspeak .

Parts needed
1x DS18B20 temperature sensor with 4.7k resistor across vcc and data pin
1x NodeMCU v1.0 (black)
1x Access Point Connected to Internet

Source code available at the footer
Thingspeak account setup, and API key acquired.

Caveat: the physical pin2 on NodeMCU v1.0 does not corresponds to pin D2 in Arduino IDE. Check out the URL in the references.
1.      It is assumed that the Access Point is able to access to internet, and a thingspeak account is set up accordingly.
2.      Connect 3.3v and gnd from NodeMCU v1.0 to DS18B20 respectively.
3.      Connect data from DS18B20 to pin4 on NodeMCU v1.0 (in code, it will be used as pin2)
4.      Connect microUSB to NodeMCU v1.0

5.      Launch ESP8266 Arduino IDE, Select Tools -> Board -> NodeMCU v1.0; and ensure parameters are correct. Refer to screenshot. 

6.      Ensure the libraries required are installed, Select Sketch -> Include Libraries -> Manage Libraries or add zip library
7.      Program the source code to read DS18B20 using one wire protocol and the acquired data to be sent to thingspeak.
8.      Compile & upload source code to NodeMCU v1.0 

9.      Observe data update of sensor data on thingspeak.

Having done the above, congratulations on sending sendor data using NodeMCU v1.0 with Arduino IDE. Now the biggest question comes begging, does this ESP8266 Arduino IDE supports all the fancy pansy libraries supported on vanilla Arduino IDE?? That is for us to discover and update on the git hub page.

Internet enable any of your creations realised on Arduino Uno (or mega) have become even simpler than previously thought. Yours truly traversed the era of sending serial data, packing data for Ethernet, WiFly, ZigBee, and now ESP8266. ESP8266 is very convenient to use.

What’s next?
Alright, time to internet enable my sous vide setup: temperature sensor DS18B20 data streamed over the Internet to a cloud computing facility to compute PID and then output the control data over the internet to control the state of the solid state relay that in turn controls the AC appliance. Earlier yours truly have controlled a IoT lamp from a virtual machine, now is to connect the dots.


thingspeak data update iframe

source code


apocalipsis said...

Two questions:
1º. Your website is wrong into the forgot "-"
2º. I want to add 3 more temperature sensors... can you tell me how to do it (i prefer to use 3 aditional digital inputs.


samith rao said...

Guys posting this comment here, felt it would be helpful.