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[SOLVED] How to check on which protocol my TV remote is working?

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Hi!
I have a Chinese TV with me and i want to know on which protocol its remote control is working without opening it.

So i used a logic analyzer and capture its waveform.
Can anyone help me in identifying which protocol is this.

On Remote I Press 1 Key and connected the TSOP1738 Output to Logic Analyzer Pin.

screenshot.png

screenshot2.png

Thanks in Advance
 

hexreader said:
Looks to me like Extended NEC protocol.

Address 0x7700 (hexadecimal) , Command 0x01, inverse of command 0xFE

As described here:

https://www.sbprojects.com/knowledge/ir/nec.php
Click to expand...


Thanks for informing me regarding this Extended NEC Protocol.

I tried to decode some other keys, Key 1, 2 and 3

On Logic Analyzer the sequence for Keys are as follow:

Key 1 = 00000000 11101111 10000000 01111111 as LSB is Transmitted first Address = 0xF700 and Command = 0x01
Key 2 = 00000000 11101111 01000000 10111111 as LSB is Transmitted first Address = 0xF700 and Command = 0x02
Key 2 = 00000000 11101111 11000000 00111111 as LSB is Transmitted first Address = 0xF700 and Command = 0x03

But you told Address is 0x7700
Can you please cross-check this once again.

Key 1
Key1.png

Key 2
Key2.png

Key 3
Key3.png
 

Yes, agreed...

0xF700 is the correct address.

Your counting is much better than mine :)
 
Thanks.

Now i am ready to write the decoding program and controlling devices with this remote.

I always receive one more pulse along with this signal which is the Repeated Pulse as NEC specs.
 

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