📡 IR Transmission

📌 Description

Infrared (IR) transmission is a way for the robot to send signals using invisible light. It’s the same technology used in TV remotes. The robot can send coded messages that another device can understand.

🎯 Use

In our projects, infrared transmission is used to:

• Control other devices wirelessly (like turning on a TV or robot module).
• Send commands without cables.
• Practice communication between robots or sensors.

👉 Think of infrared transmission as the robot’s remote control voice — it talks to other devices using invisible light signals.

 Module parameters

Pin name	Description
G	GND (Power Input Negative)
V	VCC (Power Input Cathode)
S	Digital signal pins

• Supply voltage: 3.3V/5V

• Connection: PH2.0 terminal wire

• Installation method: double screw fixing

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🖥️ Code Explanation

import machine
import irremote
import time

pin18 = machine.Pin(18, machine.Pin.IN)          # Button connected to pin 18
ir_tx = irremote.NEC_TX(26, False, 100)          # IR transmitter on pin 26

while True:
    if not pin18.value():                        # If button is pressed
        while not pin18.value():                 # Wait until button is released
            time.sleep_ms(10)
        ir_tx.transmit(0x45, 0x1c, 1)          # Send hex command (0x45)
        print(ir_tx.busy())                      # Print if transmitter is busy

Step by Step

1. import machine, irremote, time → Tools for pins, IR communication, and timing.
2. pin18 = machine.Pin(18, machine.Pin.IN) → Reads the button input.
3. ir_tx = irremote.NEC_TX(26, False, 100) → Sets up the IR transmitter on pin 26.
4. while True: → Loop that repeats forever.
5. if not pin18.value(): → Checks if the button is pressed.
6. while not pin18.value(): → Waits until the button is released (avoids multiple signals).
7. ir_tx.transmit(0x45, 0x1c, 1) → Sends a hex command (0x45) using NEC protocol.
8. print(ir_tx.busy()) → Shows if the transmitter is still sending.

👉 Together, this program makes the robot send an infrared command whenever the button is pressed.

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✅ Conclusion of the Test

• If pressing the button makes the IR transmitter send a signal, the program is working correctly.
• This test shows how the robot can send wireless commands using infrared light.
• Later, you can change the hex‑command (like 0x45) to control different actions or devices, just like different buttons on a TV remote.

button Hex-raw hex-command
1 0xba45ff00 0x45
2 0xb946ff00 0x46
3 0xb847ff00 0x47
4 0xbb44ff00 0x44
5 0xbf40ff00 0x40
6 0xbc43ff00 0x43
7 0xf807ff00 0x7
8 0xea15ff00 0x15
9 0xf609ff00 0x9
* 0xe916ff00 0x16
0 0xe619ff00 0x19
# 0xf20dff00 0xd
Up 0xe718ff00 0x18
Left 0xf708ff00 0x8
Right 0xa55aff00 0x5a
Down 0xad52ff00 0x52
Ok 0xe31cff00 0x1c