KY-005 Infrared Transmitter Module

#include <stdio.h>
#include "freertos/FreeRTOS.h"
#include "freertos/task.h"
#include "driver/rmt_tx.h"

#define IR_GPIO       GPIO_NUM_17 // KY-005 signal pin, matches the wiring above
#define RESOLUTION_HZ 1000000     // 1 MHz -> 1 tick = 1 us

// Build one NEC frame (leader + 32 bits + stop) as RMT symbols
static size_t build_nec_frame(uint8_t address, uint8_t command, rmt_symbol_word_t *symbols)
{
    uint32_t data = ((uint32_t)(~command) << 24) | ((uint32_t)command << 16) |
                    ((uint32_t)(~address) << 8) | address;
    size_t n = 0;
    symbols[n++] = (rmt_symbol_word_t){ .level0 = 1, .duration0 = 9000,
                                        .level1 = 0, .duration1 = 4500 }; // leader
    for (int i = 0; i < 32; i++) {
        bool bit = (data >> i) & 1;
        symbols[n++] = (rmt_symbol_word_t){ .level0 = 1, .duration0 = 560,
                                            .level1 = 0, .duration1 = bit ? 1690 : 560 };
    }
    symbols[n++] = (rmt_symbol_word_t){ .level0 = 1, .duration0 = 560,
                                        .level1 = 0, .duration1 = 0x7FFF }; // stop burst
    return n;
}

void app_main(void)
{
    rmt_tx_channel_config_t tx_config = {
        .clk_src = RMT_CLK_SRC_DEFAULT,
        .gpio_num = IR_GPIO,
        .mem_block_symbols = 64,
        .resolution_hz = RESOLUTION_HZ,
        .trans_queue_depth = 4,
    };
    rmt_channel_handle_t tx_channel = NULL;
    ESP_ERROR_CHECK(rmt_new_tx_channel(&tx_config, &tx_channel));

    // NEC uses a 38 kHz carrier - the RMT peripheral modulates it in hardware
    rmt_carrier_config_t carrier = {
        .frequency_hz = 38000,
        .duty_cycle = 0.33,
    };
    ESP_ERROR_CHECK(rmt_apply_carrier(tx_channel, &carrier));
    ESP_ERROR_CHECK(rmt_enable(tx_channel));

    rmt_encoder_handle_t copy_encoder = NULL;
    rmt_copy_encoder_config_t encoder_config = {};
    ESP_ERROR_CHECK(rmt_new_copy_encoder(&encoder_config, &copy_encoder));

    static rmt_symbol_word_t frame[34];
    rmt_transmit_config_t transmit_config = { .loop_count = 0 };

    while (1) {
        size_t n = build_nec_frame(0x00, 0x2C, frame); // address, command
        printf("Sending NEC address 0x00, command 0x2C\n");
        ESP_ERROR_CHECK(rmt_transmit(tx_channel, copy_encoder, frame,
                                     n * sizeof(rmt_symbol_word_t), &transmit_config));
        ESP_ERROR_CHECK(rmt_tx_wait_all_done(tx_channel, pdMS_TO_TICKS(1000)));
        vTaskDelay(pdMS_TO_TICKS(5000)); // send again every 5 seconds
    }
}

remote_transmitter:
  pin: GPIO17  # KY-005 signal pin, matches the wiring above
  carrier_duty_percent: 50%

button:
  - platform: template
    name: "KY-005 Send IR Signal"
    on_press:
      - remote_transmitter.transmit_nec:
          address: 0x0000
          command: 0x2C

[env:esp32]
platform = espressif32
board = esp32dev
framework = arduino
lib_deps =
    z3t0/IRremote

#include <Arduino.h>
#include <IRremote.h>

IRsend irsend;

void setup() {
    Serial.begin(115200);
    Serial.println("KY-005 Infrared Transmitter Test");
}

void loop() {
    Serial.println("Sending IR signal");
    irsend.sendNEC(0x00FF, 32);
    delay(5000);
}

import machine
import time

IR_TX_PIN = machine.Pin(17, machine.Pin.OUT)

def send_pulse():
    for _ in range(32):
        IR_TX_PIN.value(1)
        time.sleep_us(562)
        IR_TX_PIN.value(0)
        time.sleep_us(562)

while True:
    print("Sending IR signal")
    send_pulse()
    time.sleep(5)