Analyze any IR protocol with just you Arduino board

               Recently, I was in deep research on how to make our own "Self Learning Universal Remote". So when I searched for the procedure of making this, first step I found is analyzing IR protocol,its frequency (time period),and also the combination of High and Low pulse for making a particular carrier frequency. And for measuring all these parameters, all the people either used DSO or some other hardware and software analyzer. But I didn't have any hardware or software for protocol analyzing except my Arduino MEGA board. Yeah!!!, now you can measure all the parameters of IR remote by your Arduino board only.

Steps for analyzing Frequency and Period

IR remote transmits the data by modulating it with a carrier frequency. Hence If we want to transmit the data through our arduino board, we must be aware of the carrier frequency of the remote. Hence analyzing Frequency and Time period becomes much important parameters.For analyzing the parameters,  people used Oscilloscope and other hardware, software for this but what if we don't have anything except our Arduino Board. Lets see how we can analyze these parameters using Arduino.

Things Requied are:

Arduino Board.

Photodiode.

330 ohm Resistor.

Connect Photodiode and resistor to form a potential divider circuit.

Connect the junction point to pin 2 of your arduino board and upload this code. And press the button in front of your photodiode. You will get response like this.

This process is like trial and error method because sometimes Photodiode may give the unexpected result. So I will request you to follow this process 5-10 time to get the accurate result. 

During my research, when I was decoding various IR remotes, I found that this data i.e. 12 us High,16 us Low and 35.7 kHz frequency is most common in all the remotes. But still you can confirm the parameters using this code.

Steps for analyzing Protocol

Different IR remotes follows different protocols. As I have also written blog for Samsung and NEC protocol previously, In that you can observe the difference. So after analyzing frequency and period, next step is to decode the data transmitted form that remote. 

Things Requied are:

Arduino Board

TSOP IR receiver

Connect TSOP's signal pin to pin2 of your Arduino board. And upload this code to your board.

After uploading, open the serial monitor, It will show "Press the button once".

After that press the button of your remote ONLY ONCE. Because:

Case i)

In case of AC remotes, whenever we press the button it will transmit whole data of that button only once even if we have pressed the button for quite long time. Hence we must press the button only once. By pressing the button for the second time, the buffer in the code will be overflowed and the arduino will restart.

The Response we get when we press button of panasonic AC remote is as follows:

So the data of 439 bits is received when we press the button once. And yes this much amount of data is sent in every button. Now this data is in form of time duration, so we need to convert it into binary form to analyse it. For that we must be aware that which type of encoding is done in this. Every IR remote uses Pulse Distance Coding i.e. PDC for encoding the data. Hence whether the bit is 1 or 0 can be decided by the duration of the LOW time in signal. Duartion of HIGH time in signal will be constant around 500 us, so we need not to consider HIGH time whenever converting it into binary form.

If the duration of LOW time is around 300 to 400 us, than that bit is binary '0'

and

If the duration of LOW time is around 1200 to 1300 us, than that bit is binary '1'.

You can analyse the received data and recognize the START bit, STOP bit, binary '1' and binary '0' by below mentioned range.

So the received data will be around the mentioned range and with the help of this we can easily decode the received data. Lets decode the data which is received in the above image.

So this is the decoded data of my Panasonic AC. Than convert this data into 8 bit HEX code. Panasonic AC protocol consists of 8 bytes constant data and 19 bytes of other data which contains information of Temperature, Fan speed etc. In total there are 27 bytes of data, which is transmitted when we press single button of the remote.

You can search for different protocols for decoding binary '1' and binary '0'. But if you don't get any information, you can go for this logic,

first bit will be always start bit. and last bit will be always stop bit.

if low duration is greater than 1000 us , than it is binary '1'

and

if low duration is less than 1000 us , than it is binary '0'.

I don't know that this will work for all the appliances or not but mostly this will work.

Case ii)

In case of TV,Setup box, Radio remotes the data is transmitted continuously as long as the button is pressed. Even if the data of that particular remote is sent, it will repeatedly send the same data as long as the button is pressed. 

So, we need to press the button only once so that data is recorded only once. When I press the Remote of Radio which follows NEC protocol, the response I get is as follows,

So I received 75 bits of data which is not the true number in case of a NEC remote. Because NEC protocol sends only 34 bits(34*2=68 bits  Here two is multiplied because for one bit we receive both High time and low time) of data including start bit and stop bit. But what if we don't know which protocol is this and how many data bits are their in that protocol??? In that case we need to look after the Stop bit. Now the question is how to recognize the stop bit. Stop bit of most of the protocols is a long duration of Low time. The duration is much longer as compared to the other bits in the signal, hence it easily gets highlighted in the serial monitor. The stop bit in this protocol is shown below,

In NEC protocol, the stop bit is 40,000 us long. Hence get easily noticed. So the exact data of the single button of NEC remote is upto this stop bit ( including stop bit).

And again, we can convert this data in its binary form by decoding the duration of Low time pulses.

Start bit High Time - 9050 - 9150 us

Start bit Low Time - 4450 - 4550 us

Data High Time -     450 - 650 us

Data Low Time '1' -   1650 - 1750 us

Data Low Time '0' -   450 - 550 us

Stop bit High Time - 450 - 650 us

Stop bit Low Time - around 40,000 us 

So with this you can convert this duration into binary data. In NEC protocol data format is like 

Start bit - Address byte - Inv. Address byte - Data byte - Inv Data byte - Stop bit.

So this is how you can analyze the protocol and parameters of different IR remotes by just using you arduino board. I tried my best to explain this topic in as simple way as possible, still if you have any doubt feel free to ask me by email or just comment below.

I have also made video on this topic, have a look.

You can download Codes from here.

#techiesms.

Fetching Data from any Website

             This Project idea struck in my mind during the time of IPL(Indian Premier League) when we used to be in our class attending lecture and we guys are so much curious about the live status of the match. At that time I thought of a small screen on which we can get regular updates of the match. And the Research Begins.........

            Visualizing it in block diagram wise, first of all we need search for a website on which we can get the live updates of whatever we want like live stock prices,current time, current temperature,YouTube Views,likes  and many more. Later we need to fetch the data from the server of that website and make an API(Application Program Interface). API serves the purpose of getting access to only those data which we are in need of from all the data available on the server.Suppose we need only number of views of our video uploaded on YouTube. So we need a interface which rather than requesting the whole HTML page, requests only number of Views of our video. Than we will give a GET request as we want to fetch the data from the server. All this task will be done through Thingspeak.com . A great website for your IoT based projects.

             In thingspeak.com, we will get our required API.  To test the API just request the link provided by thingspeak(On the right side of the page) in your browser than you will only get the data for what you requested.

In this Image,  I have created an API of number of views of my YouTube Video. Method I selected is GET as we want to fetch the data and HTTP version is 1.0. Than I Inserted URL of the page and for the last row (Parse String) you need to follow following steps.

Now paste that XPath into parse string row and thats it save it and API will automatically get generated. Test it by pasting that link into your browser. Than it will show something like this.

This is all about to pick up the right data.But what if we want to make project based on this. To make this data more useful you will require Arduino, LCD and the most amazing thing ESP8266 ( WiFi Module).

ESP8266(WiFi module)

             This is an absolutely amazing thing which will help your controller to communicate to the virtual world.And it is very easy to use. It has a on chip controller and we can communicate with this WiFi Module via AT Commands.Here is the list of all AT Commands.

If you are using Arduino Mega than you can use Serial1(RX1 and TX1) and Upload MultiSerialMega code into you board and change the baud rate to 115200 and you are ready to use WiFi Module. Just use all this AT commands once so that it will get easier to deal with this module further.

Steps for fetching data through API

Step 1:

Reset the WiFi module :- AT+RST

Set the mode to 3:- AT+CWMODE=3

Join any WiFi network :- AT+CWJAP = "SSID_Name","SSID_Password"

Step 2:

After connecting to the WiFi network, we need to establish a TCP connection to communicate with servers via port 80. To establish a connection, the AT command is,

AT+CIPSTART = "TCP","api.thingspeak.com",80

In our project, we are using API generated from Thingspeak.com so we have written the host server name as api.thingspeak.com. 

After this command we need to provide that how many number of characters we need to request. For this the command is,

AT+CIPSEND=90

in our case the number of characters are constant i.e. 90. Because different APIs from thingspeak.com will have different api key rest of all the things will remain same.

Step 3

After that we need to request the api generated from thingspeak.com. As we want to get the data from the server, we will send a GET request. And the sequence goes like,

GET /apps/thinghttp/send_request?api_key=XXXXXXXXXXXXXXXX 

Host: api.thingspeak.com

So whenever you make a new api, just change the key and leave rest of the things as it is.

Step 4

After following all the three steps, you will get the data in response. But many times the we need to filter the required data from the response we get.So for that we need to filter the required data form the response. And this can be done easily through some of the commands of String which I have mentioned in the code.

             This is all you need to know if you want to  fetch the data from internet and use it further for your project. I have made one sample project so that it becomes easier for you to understand the whole concept. This is the same project on which I have recorded the video i.e. fetching data from website and display it on your touchscreen. 

             If you don't have touchscreen module, just filter out the required data and analyse the response from the server on your serial monitor.

If the concept is still not cleared than have a look to my video tutorial for this whole procedure. And I have also shared the Arduino code for the same.


#techiesms

Getting Started with WiFi Module(ESP8266)

In this section we will see how to use this tiny little still most useful module ESP8266. Main reason for the popularity of this module is I think its price and its features. It is easily and cheaply available in the market for just ₹ 250-300.

The ESP8266 is a micro-controller from Chinese manufacturer Espressif that includes Wi-Fi capability.This small board allows micro-controllers to connect to a WiFi network. This little module can work in station mode, access point mode or both. Each ESP8266 module comes pre-programmed with an AT command set firmware.

First of all lets see the pins of this module. We can communicate with this module via serially. We can use either USB to TTL converter or you can use your Arduino board as I have used.

Pins of ESP8266 module 

Things Required are:

1. BreadBoard
2. Arduino Board
3. ESP8266 WiFi module
4. LD33CV IC ( 3.3V regulator IC)
5. Resistors (1k & 2.2k)
6. Some connecting wires

STEP - 1

As this module is not breadboard friendly, you need to follow the steps shown below before using this module.

Cut a piece of prefboard, and first solder female connector as shown in the fig below.

After that, solder male headers on the opposite side of the prefboard. It would look something like this.

Now attach the module on to the converter.

With this, it can be easily connected on to the breadboard.

STEP-2

Note: This module strictly works on 3.3V do not give 5V supply to this module.

As this module works on 3.3V we need to use a 3.3V regulator IC (LD33CV) or you can also use 3.3V pin from your arduino board. Even the Tx pin of arduino will provide 5V signal to the module. Hence we need to step down the signal to around 3.3V before feeding it to the module.

Connection of all this things is shown in the fig. below.

I have used the Rx1 and Tx1 of Arduino MEGA board. But you can even use the Rx and Tx pins. I have used this pins beacuse in my further WiFi projects, I have used TFT touch screen module, hence we won't be able to use pin 0 and 1.

Open Arduino software and open Multi Serial Mega example and change the baud rate to 115200 and upload the code. Change the baud rate in serial monitor to 115200 and the mode to Both NL & CR.

STEP-3

Now communicate with this module by sending the AT commands in the Serial monitor and play with this module.List of  AT commands are given in the PDF whose link is mentioned below.

I have also made a video on "Getting Started with ESP8266, As simple as possible"                                                                                

Datasheet of ESP8266

   AT Commands 

#techiesms

IR Protocol Decoding and Transmiting through Arduino

In this blog, I will described various IR protocols adopted by different companies and will go in detail about 2 protocols. One is the most commonly used NEC protocol and another is the Samsung protocol. Why??? Because I have Samsung TV which uses its own protocol and a GTPL setup box, which uses NEC protocol as simple as that.

Source: Wikipedia

Different Companies uses their own protocols for eg. we have protocols like Samsung, LG, RC5/RC6 by Philips,and the most commonly used protocol NEC protocol.

Lets discuss the two protocols in detail.

SAMSUNG Protocol

Samsung protocol goes in sequence like a start bit,8 bit address,8 bit address,8 bit data and inverse of 8 bit data. In total there are 32 bits after start bit containing address and data.Start bit of this goes like HIGH for 4.5 ms and LOW for 4.5 ms. Followed by this start bit, address and data bits are transmitted. Frequency of transmission is around 38 kHz. To be precise it is 37.9 kHz. Level HIGH and level LOW is decided based on the duration on the low level of the signal. Logic 1 and 0 is decoded like this:

IR signal of samsung protocol will look something like this, and its sequence goes like

start bit - Address - Address - Data - Inverse Data - stop bit

start bit- 11100000 11100000 00100000 11011111-stop bit

This signal contains address - 11100000   data - 00100000.

NEC Protocol

                                    

NEC protocol is most commonly used for IR communication. Its frequency of transmission is around 38kHz. The difference in samsung protocol and NEC protocol can be easily identified by the start bit. Samsung has 4.5 ms mark and 4.5 ms space while NEC protocol have a start bit of 9 ms mark and 4.5 ms space.

Another difference between samsung protocol and NEC protocol is that NEC protocol contains Address and inverse of Address after that while samsung protocol repeats the address twice. Logic 1 and 0 of this protocol is same as that of samsung protocol.

Decoding and Transmitting Through Arduino

Decoding this signal using arduino is very simple. We will use pulseIn() function to read the duration of the pulse and accordingly decide weather the received bit is high or low.

Things Required;

1. Arduino Board

2. TSOP IR reciever

3. IR LED 

TSOP IR reciever will give digital output of the IR data received on 38 kHz frequency. By default, it will give digital 1. 

Note: This receiver will give the inverse output. i.e. If IR signal transmitted is 0, than TSOP reciever will give output 1.

DECODING:

STEP 1:

First of all we will wait for the start bit of the signal. After that we will turn ON the led for indicating that IR signal is received.(This is the example of decoding a NEC IR signal).

STEP 2:

Than we will check that whether the received data is logic 1 or 0 and we will store that 32 bit data in a boolean array.

STEP 3:

Than we will separate address and data from this array. Now as we know that in NEC protocol the first 8 bits are the address and 17th to 24th bit are the data. Hence we will sort it accordingly.

Thats it. We have decoded the NEC protocol. Now lets see how to transmit it via IR LED.

TRANSMITTING

STEP 1:

First of all we will make a array of 32 bit and store the address in first 8 bits and the inverse of the address in another 8 bits. I am fetching the address value in integer from EEPROM.

STEP 2:

Than we will store the data and inverse of the data in the remaining 16 bits of the array.

STEP 3:

Than we will transmit this 32 bit data along with start bit and stop bit.Start bit of NEC protocol is HIGH for 9 ms and LOW for 4.5 ms. Here burst is the function which will send the HIGH signal at 38kHz frequency.

Burst is the function which will send pulses at 38 kHz frequency. Value of the burst signal may vary because of the time delay of the instructions. So I have tried by different divisions, and finally the transmitter was working when I divided the HIGH time delay by 38 for which actual dividend by calculation comes out to be 26 (9 us+17 us).

That's it. You are done with the decoding and transmission. You can even store the codes of the remote sequentially in the EEPROM and than transmit the code by fetching the data from EEPROM.
The pics in this blog are example of NEC protocol. I have attached link of a code for decoding and transmission  of code of Samsung protocol.

Further I am trying to make a self learning universal remote control which can simply copy the code into the memory and can be able to transmit the same signal. So that the issue of different protocols will be nullified.If any one have any idea regarding learning remote, do mail me.


Arduino Files:

Samsung Protocol Decoder
Remote Transmitter


#techiesms

HeartBeat sensor

             "Heart Beat Sensor" sounds very complicated to be made.But its not the reality, it is the most simplest medical device to make at home using very few components.

Heart Beat Sensor

 Components required to make a Heart Beat Sensor are:-

Components

1. Proximity Sensor
2. LM 358 IC
3. 4.7uF and 100nF Capacitors
4. 47k,6.8k,680k, and 1k resistors.
5. Some LEDs.

            

             First let us discuss the connection of the circuit. 

• First we need to connect the proximity sensor with transmitter in forward bias and receiver in reverse biased. 
• After that fed the signal of from the receiver to High Pass Filter.
• Than amplify this signal by feeding the signal into Non Inverting Amplifier.
• Output of the amplifier will be pulses proportional to heart beat.
• If we want to fed the signal into controller, than we will require an additional buffer amplifier.

Circuit Diagram

Now, discussing some theory of this circuit. Logic behind this is that when our heart beats, the blood circulates in our body. Due to this, their is minute volume change of blood on our index finger. Hence when we place our finger on the proximity sensor, that sensor senses that volume change and gives signal accordingly.

But this signal is very weak to even drive an LED. Hence we connect an Amplifier to amplify this signal. On the output of the amplifier,we will get the pulses which will be proportional to the Heart Beat. Our Heart Beats will be indicated by the LED connected at the output. 

Further if we want to fed this signal into the micro-controller, we need to attach an additional buffer to this circuit. In the micro-controller we can code that controller so that we get exact value of our Heart Beat.

So this is all about making your own Heart Beat Sensor. You can even watch my tutorial video on this in which I have made this sensor using SMD components. The link of the video is mentioned below.

Make a one for yourself and if you like this project, than share it with others.

Tutorial Video Link:- https://www.youtube.com/watch?v=VJ3nCVzQZUU

#techiesms

3D Hologram Projector.

             3D hologram projectors are pretty cool. They may seem to be very complex technology and they really are. But there is a very simple way for you to make one yourself. At your home.Just have a look.

 Their exists a strategy for turning smartphones into 3D hologram projectors that involves a plastic CD cover, a glass cutter, a sheet of paper, some tape, Strong glue and a pen.

Things Required

Draw a trapezium on the white paper with dimensions 1cm x 3.5cm x 6cm.

Draw this shape on paper.

Cut the trapezium with the help of the cutter.

                                           Cut the shape.

Take an CD cover and carefully cut out the edges.

Cut out the edges

Cut the shape and cut 3 more such pieces.

Cut four such pieces

Stick them together with the help of the tape.

Stick them together with tape.

In the end, apply strong glue at the junction and remove the tape.

Remove the tape after applying strong gule,

Now place it Upside down on your smart phone and play the hologram video.You can even make our own customized videos as I have made.

Holographic video of Myself

             Try to make out one for yourself and experience the magic of Technology.I have made the tutorial video for this, Just have a look.



Tutorial Video : https://www.youtube.com/watch?v=7cM1Z_1ddX4

Hologram Sample videos: https://www.youtube.com/watch?v=Y60mfBvXCj8


#techiesms

SMART MANDIR's Journey

               The whole concept,working and public reviews are their in the videos. But I'll talk something about which is not their in the videos. Something like behind the scenes of  SMART MANDIR. I'll share my experience of making this project to reality.

            

          SMART MANDIR DIARIES

“Navratri is on head. Think something innovative this time for the decoration of mandir.” My mother asked.

I started working on it. Initially, the only thing that struck the mind was to decorate the mandir, simply with LED strips along with arduino, coded with different patterns that run continuously. I was still not contented.

“How about a high end humanoid robot that offers prasad to all devotees, same as my mother do after aarti ends???” I thought.

Finally, I came up with an idea.

I remembered a line follower car which could work as robot in my project. I started thinking about how to arrange things that would amaze all. Many ideas and thoughts crowded the room of my mind.

It was time for some action.

I called up my friend AKSHAY who is a great coder and a great Techie. We discussed lot together regarding the project and it was no time for Navratri, just 2 days left.

 Firstly, we completed the creative part - decorating the mandir. It was already one day down; we started working on the second part of our project - the core part i.e. Coding and Debugging.

Every great idea requires great efforts.

We tried numbers of codes to make our project look automatic and hassle free. We failed every time trying new codes.

As great THOMAS A EDISON said, “Our greatest weakness lies in giving up. The most certain way to succeed is always to try just one more time.”

We tried once more and not ended trying till we got it. Finally, the idea turned to reality.

I looked at my friend AKSHAY, we smiled…

Two days of hard work, two days of dedication, two days of creativity and coding, two days for ‘SMART MANDIR’.

#techiesms