Bored with your old fashioned TV remote??Here's a new concept. Control your TV with smartphone. You can also extend it to any other gadget also that uses the IR transmission system like AC,media player,etc. We know that smartphone with IR blaster in-build can do that, but in case you don't have such expensive phones then you can also do the same with arduino with an android app build using MIT. Believe me, it will be a great fun than using the pre made IR blaster of phones. I build this project so as to make some change in using the old traditional way of button remotes and build our own remote and this would be a lot of fun. So let's get started.
Step 1: Parts Required
1. Arduino Uno/Nano/mega/micro
2. HC-05 bluetooth module (1pc)
3. IR Led(1pc)
4 TSOP IR 38Khz receiver (1pc)
4. 220ohm, 2.2Kohm and 4.7Kohm resistor
6. Breadboard/Solder kits
Step 2: Working Principle
This remote actually works with bluetooth. The app actually uses bluetooth for the signal transmission. When we press a key the mobile sends 1 byte number to the HC05 module. HC05 accepts that value and the required signal is transmitted via the IR LED. The IR receiver of TV accepts the signal and acts accordingly.Refer to the block diagram for better understanding.
I have made 15keys. Power on/off, 0-9,vol+,vol-,ch+,ch-. You can increase it to any number of keys you may like and you have to make it on the MIT app inventor tool likewise. I will tell that in upcoming steps.
Step 3: Getting HEX Codes From Your TV Remote
Now for making the remote you need to get the HEX codes of your TV remote. This is accomplished by a TSOP 38khz IR receiver and arduino. Download Fritzing http://fritzing.org/home/ and open the file I have attached. Connect in breadboard.
Now download the IR library https://github.com/z3t0/Arduino-IRremote
Extract the files into arduino->libraries folder.
Now open arduino IDE and then File->examples->IRremote->IRrecvDumpV2 sketch. Upload it and open the serial monitor. Now take the remote whose buttons you want to implement in the app.Point it towards the TSOP receiver You will get the complete info about the signal. Now you only need the HEX code. See the screenshot and you will get it. Now you may get arbitrary values since IR from atmosphere interfere. So repeat the process and see if same code is coming. Copy the codes in a paper. Important switches might be PowerOn/Off, VOl+,VOL-,Ch+,CH-,0-9, or any other switch you might need.copy all the codes in a paper.
This way you actually copied the whole remote. Good Luck. ;-)
Step 4: Building the Actual Setup in Breadboard and Uploading Code
Now as you have copied all the HEX codes it's time to build the actual setup for the signal transmitter. Remove the TSOP and now take a look at the above fritzing file and build the circuit on breadboard.
The sketch is attached here.
Now you have to modify the HEX codes in the sketch since your and mine remote will never have the same HEX code.See the screenshot in the sketch and you will easily understand where to change. Write there your own HEX code of your remote which you recorded previously.
Now as you upload the code,make sure the RX-TX lines are removed.After uploading, reinsert it.
Step 5: Building the App
I used MIT app inventor tool for making the app. http://appinventor.mit.edu/explore/
I referred to YouTube for tutorials of making the app. You can add more buttons. See the screenshot, I have shown one button here.You can add more buttons in the same way. See that each button will send a one byte number. It can be easily seen in the Blocks section.I have also attached the apk here. You can download it. It will work fine.
Step 6: Finally Opening Bluetooth and Use It...
Now power up the circuit and you should see the led of HC05 flashing rapidly. Now install the app on your phone,open Bluetooth and connect to HC05. If connecting for first time, pair your HC05 before using the app. usual pass is 0000 or 1234. After connecting you should see connected and led of HC05 should now blink slowly. If not try again.
Keep the circuit near your TV and point the IR LED towards your TV by slightly bending.
Now press any button and you must see it's working. If not working, check if you have taken the HEX codes properly and wrote it on the final sketch or not. If you have written properly it will work 100.....00% sure. See my pics above. If any problem occur comment below. See pics for reference.
Now if you wish to solder you might do on a perfboard.
So your new alternative remote is complete. Enjoy your show!!!