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Course – Arduino

Requirements

  • A Windows, Mac or Linux computer
  • An Arduino Uno
  • Electronics parts like resistors, LEDs, sensors, as listed in Section 1 of the course
  • Essential tools: a mini breadboard, jumper wires, a multimeter, a soldering iron and solder, wire cutter
  • Be excited about electronics!

Continue reading Course – Arduino

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ESP8266 MQTT broker BONDAR.

Create an account

  • Create an account in here
  • Activate your iotcentral account

 

Download Bin FIle

 

Flash the Bondar Firmware

  • your ESP8266 starting from address 0x0. (Use esptool.py or ESP Flash Download Tool)
  • For Linus
    • sudo esptool.py -p /dev/ttyUSB0 --baud 9600 write_flash -fs 32m-c1 -fm dio -ff 40m 0x00000 bondar.bin

 

ESP8266 Configuration

  • ESP8266 will start as Access Point mode. and named as Bondar_XXXXXXXXX  . (Ex refer Below image : Bondar_2e3ae80cb19a ) and should use default password 12345678

  • Now connect that AP Network (Bondar_2e3ae80cb19a ) with your laptop or mobile.
  • Go to 192.168.4.1 in your browser and you will get a configuration page. Then enter your wifi Credential and your he user and password used on IoTCentral.eu

  • Reset the ESP8266 by Click button and also unplug and re-plug the power cable (I recommend you to unplug and then plug the power cable).
  • After Rest you can see when did soft web browser reset button

IoTCentral.eu Account Details

  • Login to your home page on IoTCentral.eu
  • You will see your allocated topic
  • Use allocated_topic/your_topics to connect to iotcentral.eu:1883 and /allocated_topic/your_topic to connect from your Wi-Fi network.

Note :   Always use your email address and the password used on IoTCentral.eu to publish and subscribe. In this way your data is protected and no one will get access to your data since the topic is secret and you are using your username and password to publish and subscribe to the cloud.


Important :  i was tried that on 20171005 but its not work so i need to check again  once if its work i will update everything whenever I’m free. feel free to contcat anything regard this demo @ +919047474939 and Arun9047474939@gmail.com.


 

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Embedded Interface – MCP23017

Features

  • 16-bit input/output port expander with interrupt output
  • 16 bit serial interface
  • Cascadable for up to 8 devices on one bus
  • 25mA sink/source capability per I/O
  • Supports 100kHz, 400kHz and 1.7MHz I2C™Compatible compatible modes

 

Pin Details

INTA and INTB

  • There are two interrupt pins, INTA and INTB, that can be associated with their respective ports, or can be
    logically OR’ed together so that both pins will activate if either port causes an interrupt.

(IODIRA/B)

  • system master can enable the I/Os as either inputs or outputs by writing the I/O configuration bits
    IOCON.BANK – The MCP23X17 can beconfigured to operate in the 8-bit or 16-bit modes via “IOCON.BANK.”

Data Sheet :

  • 2005-2016 http://ww1.microchip.com/downloads/en/DeviceDoc/20001952C.pdf
  • 2007 http://ww1.microchip.com/downloads/en/DeviceDoc/21952b.pdf

Examples

  • Interfacing a 4×4 Matrix Keypad with an 8-Bit GPIO Expander
    • http://ww1.microchip.com/downloads/en/AppNotes/01081a.pdf
  • Expanding the number of I/O lines using Microchip MCP23008
    • http://embedded-lab.com/blog/expanding-the-number-of-io-lines-using-microchip-mcp23008/
  • Unique Features of the MCP23X08/17 GPIO Expanders
    • http://ww1.microchip.com/downloads/en/AppNotes/01043a.pdf
  • MCP23008 port expander interfaced to PIC12F683
    • http://embedded-lab.com/blog/expanding-the-number-of-io-lines-using-microchip-mcp23008/

reference Link

  • http://www.microchip.com/wwwproducts/en/MCP23017
  • https://github.com/nodemcu/nodemcu-firmware/tree/master/lua_examples

 

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Embedded Interface – EEPROM

Getting Started With AT24C128 I²C EEPROM

Feature

  • Voltage
    • Low Voltage (1.8v to 3.6v)
    • Standard Voltage (2.7V to 5.5V)
  • Memory
    • 128K (16,384 x 8)
    • 256K (32,768 x 8)
  • I²C Interface (Bi-Directional data transfer protocol)
  • Speed
    • 1MHz(5v)
    • 400KHz(2.7v, 2.5v)
    • 100kHz(1.8v)
  • High Reliablility
    • 1 Million write cycles of endurance
    • 40 years of Data Retention

At First Lean this

Datasheet

Useful Resource

 See Also


 

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Learn Electronics – Resistor

 

 

 

Resistor is a passive two terminal electronic components. It function is to limit or reduce(resist) the flow of current or divide the voltage in a circuit. The unit of the resister is ohm(Ω). The resistance r of any material is proportional to its length and inversely proportional to its area of cross section A.

R=ρl/A

ρ=specific resistance or resistivity of the material.

Symbol

Resistor Type

  • Fixed Resister
    • Wire wound resistor
    • Carbon film resistor
    • Metal film resistor
    • Carbon composition resistor
    • Carbon resistor
    • Film type resistor
    • Chip resistor
  • Variable Resister
    • Rheostat
    • Potentiometer
    • Trimmer
    • Preset

Resistor Color Code

Color
Digit value
Multiplier
Multiplied Out
Tolerance
Black
0
100
1
 
Brown
1
101
10
 
Red
2
102
100
 
Orange
3
103
1,000
 
Yellow
4
104
10000
 
Green
5
105
100,000
 
Blue
6
106
1,000,000
 
Violet
7
107
10,000,000
 
Gray
8
108
100,000,000
 
White
9
109
1,000,000,000
 
Gold
     
±5%
Silver
     
±10%
 

Measuring power across a resistor (Ohm’s Power Law)


Series and parallel resistors

Series
Parallel


 
 

 

 
 
 


Ohms Law

Ohm’s law describes the fundamental behavior of
resistors.


LED Current Limiting

For example, assume you have a 9V battery to power an
LED. If your LED is red, it might have a forward voltage around 1.8V. If you
want to limit the current to 10mA, use a series resistor of about 720Ω.
 


Kirchhoff’s Law

 

Kirchhoff’s law can be used to analyses networks
of resistors.


Resistor networks

 


Voltage Dividers

 


Resistive properties of materials

Material
ρ (Ωm) at 20°C
σ (S/m) at 20°C
Temperature coefficient (1/°C) x10^-3
Silver
1.59×10−8
6.30×107
3.8
Copper
1.68×10−8
5.96×107
3.9
Gold
2.44×10−8
4.10×107
3.4
Aluminum
2.82×10−8
3.5×107
3.9
Tungsten
5.60×10−8
1.79×107
4.5
Zinc
5.90×10−8
1.69×107
3.7
Nickel
6.99×10−8
1.43×107
6
Lithium
9.28×10−8
1.08×107
6
Iron
1.0×10−7
1.00×107
5
Platinum
1.06×10−7
9.43×106
3.9
Tin
1.09×10−7
9.17×106
4.5
Lead
2.2×10−7
4.55×106
3.9
Manganin
4.82×10−7
2.07×106
0.002
Constantan
4.9×10−7
2.04×106
0.008
Mercury
9.8×10−7
1.02×106
0.9
Nichrome
1.10×10−6
9.09×105
0.4
Carbon (amorphous)
5×10−4 to 8×10−4
1.25 to 2×103
-0.5


Resister Application

  • variable resister is used in volume control in
    the TV application,
  • LED Current Limiting


Examples


Example 1

find the resistance of a copper
wire of 0.75km long and having a cross sectional area of 0.01cm2.
(take ρ=1.72×10-8ohm-m).
ANS=12.9ohm


Example 2

find the cross sectional area of
an aluminium wire of 700m long and having a resistance of 0.24ohm (take ρ=2.83×10-8ohm-m)
ANS=8.254×10-5m2.


Example 3

 if a R = 300 ohm resistor is attached
across the terminals of a V = 12 volt battery, then a current  of (V/R)12 / 300 = 0.04 amperes flows
through that resistor.


Example 4 (Ohm’s law equations)

Consider
a 1-ohm resistor in a circuit with a voltage drop from 100V till 10V across its
terminals. What is the current through the resistor?
The
triangle reminds us that:


Example 5 (Ohm’s law equations)

Consider
a 10-ohm resistor in a circuit subject to a current of 2 Ampere and a voltage
of 120V. What is the voltage drop across the resistor?
Using
the triangle shows us that:


Answerer
Thus the voltage at the end terminal is 120-20
= 100 V.
 


Example 6 (Ohm’s Power Law)

What must be the minimal power rating of this resistor?

Answer:
According to the wheel, P=I^2*R= 0.100^2*50=0.5 W. So the minimal power
rating should be at least 0.5W, but recommended is to go high above this value
for extra reliability and lifetime.


Example 7 (Ohm’s Power Law)

What is the current in the circuit?


This is a basic example of Ohm’s law. Voltage and resistance are known,
so we can calculate current with the equation:

I=V/R=6/1.2=5 A.


Example 8 (Ohm’s Power Law)

An electric heater (resistor) with a consumption of 1kW
is connected in a circuit with 8A current. What is the voltage drop over the
heater?

Voltage can be expressed in current and power with the formula:
V=P/I= 1000/8=125 V
 


See More


Watch Video Tutorial


 


Reference Website



 

Basic Electricity – Resistance and Ohm’s law

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ESP8266 Arduino-Core Tutorial – Web Server

TCP Server Listener

The below Arduino code will also create a server and Access Point in ESP8266 which will continuously listen for a connection.

Code

After uploading this sketch, you can find a new Access Point named “test” from your Laptop or PC.

Result