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			111 lines
		
	
	
		
			4.0 KiB
		
	
	
	
		
			Markdown
		
	
	
	
	
	
			
		
		
	
	
			111 lines
		
	
	
		
			4.0 KiB
		
	
	
	
		
			Markdown
		
	
	
	
	
	
| | Supported Targets | ESP32 | ESP32-C3 | ESP32-C6 | ESP32-H2 | ESP32-P4 | ESP32-S2 | ESP32-S3 |
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| | ----------------- | ----- | -------- | -------- | -------- | -------- | -------- | -------- |
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| # IR NEC Encoding and Decoding Example
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| 
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| (See the README.md file in the upper level 'examples' directory for more information about examples.)
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| 
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| [NEC](https://www.sbprojects.net/knowledge/ir/nec.php) is a common use IR protocol, this example creates a TX channel and sends out the IR NEC signals periodically. The signal is modulated with a 38KHz carrier. The example also creates an RX channel, to receive and parse the IR NEC signals into scan codes.
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| 
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| ## How to Use Example
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| 
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| ### Hardware Required
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| 
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| * A development board with supported SoC mentioned in the above `Supported Targets` table
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| * An USB cable for power supply and programming
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| * A 5mm infrared LED (e.g. IR333C) used to transmit encoded IR signals
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| * An infrared receiver module (e.g. IRM-3638T), which integrates a demodulator and AGC circuit
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| 
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| ### Hardware Connection
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| 
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| ```
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|    IR Receiver (IRM-3638T)                 ESP Board                        IR Transmitter (IR333C)
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| +--------------------------+       +----------------------+              +---------------------------+
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| |                        RX+-------+IR_RX_GPIO  IR_TX_GPIO+--------------+TX                         |
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| |                          |       |                      |              |                           |
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| |                       3V3+-------+3V3                 5V+--------------+VCC                        |
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| |                          |       |                      |              |                           |
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| |                       GND+-------+GND                GND+--------------+GND                        |
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| +--------------------------+       +----------------------+              +---------------------------+
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| ```
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| 
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| The TX and RX GPIO number used by this example can be changed in [the source file](main/ir_nec_transceiver_main.c) via `EXAMPLE_IR_TX_GPIO_NUM` and `EXAMPLE_IR_RX_GPIO_NUM`.
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| 
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| ### Build and Flash
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| 
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| Run `idf.py -p PORT flash monitor` to build, flash and monitor the project.
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| 
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| (To exit the serial monitor, type ``Ctrl-]``.)
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| 
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| See the [Getting Started Guide](https://docs.espressif.com/projects/esp-idf/en/latest/get-started/index.html) for full steps to configure and use ESP-IDF to build projects.
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| 
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| ## Example Output
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| 
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| Run this example, you might see the following output log:
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| 
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| ```
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| ...
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| I (0) cpu_start: Starting scheduler on APP CPU.
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| I (306) example: create RMT RX channel
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| I (306) gpio: GPIO[19]| InputEn: 1| OutputEn: 0| OpenDrain: 0| Pullup: 1| Pulldown: 0| Intr:0
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| I (316) example: register RX done callback
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| I (316) example: create RMT TX channel
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| I (326) gpio: GPIO[18]| InputEn: 0| OutputEn: 1| OpenDrain: 0| Pullup: 1| Pulldown: 0| Intr:0
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| I (336) example: modulate carrier to TX channel
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| I (336) example: install IR NEC encoder
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| I (346) example: start RMT TX and RX channel
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| 
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| NEC frame start---
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| {0:9020},{1:4461}
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| {0:577},{1:577}
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| {0:577},{1:576}
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| {0:552},{1:601}
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| {0:552},{1:601}
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| {0:577},{1:576}
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| {0:578},{1:575}
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| {0:583},{1:572}
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| {0:579},{1:574}
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| {0:576},{1:1648}
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| {0:553},{1:1673}
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| {0:579},{1:1647}
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| {0:580},{1:1645}
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| {0:577},{1:1649}
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| {0:554},{1:1673}
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| {0:578},{1:1648}
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| {0:553},{1:1673}
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| {0:555},{1:1671}
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| {0:578},{1:577}
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| {0:553},{1:1673}
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| {0:554},{1:1671}
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| {0:555},{1:601}
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| {0:580},{1:574}
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| {0:551},{1:603}
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| {0:580},{1:574}
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| {0:553},{1:601}
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| {0:553},{1:1672}
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| {0:554},{1:602}
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| {0:552},{1:603}
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| {0:579},{1:1646}
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| {0:554},{1:1672}
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| {0:555},{1:1672}
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| {0:580},{1:1646}
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| {0:555},{1:0}
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| ---NEC frame end: Address=FF00, Command=F20D
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| 
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| NEC frame start---
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| {0:9024},{1:2213}
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| {0:583},{1:0}
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| ---NEC frame end: Address=FF00, Command=F20D, repeat
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| 
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| NEC frame start---
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| {0:584},{1:0}
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| ---NEC frame end: Unknown NEC frame
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| 
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| ...
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| ```
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| 
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| In the example's main loop, the RX channel waits for any NEC frames, if nothing received within 1 second, the TX channel will send out a predefined NEC frame (address=0x0440, command=0x3003).
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| 
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| ## Troubleshooting
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| 
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| For any technical queries, please open an [issue] (https://github.com/espressif/esp-idf/issues) on GitHub. We will get back to you soon.
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