I'm newbie in C too and i want to write functions same to Michele's. It's softcode and we can config parameters such as timer, channel, resolution bits, gpio output pwm. But it didn't work (no PWM signal). I'm stuck here and thankful to any help

I use same reference manual as Michele.

#include "pwm.h"

// ===== Peripheral control registers =====
#define DPORT_PERIP_CLK_EN_REG       (*(volatile uint32_t*)0x3FF000C0)     // Enable peripheral clocks
#define GPIO_ENABLE_W1TS_REG         (*(volatile uint32_t*)0x3FF44024)     // Enable output for GPIO < 32
#define GPIO_ENABLE1_REG             (*(volatile uint32_t*)0x3FF4402C)     // Enable output for GPIO >= 32
#define GPIO_FUNC_OUT_SEL_CFG_REG(n) (*(volatile uint32_t*)(0x3FF44530 + (n) * 0x4))   // GPIO output signal selection
   
// ===== IO_MUX register addresses for each GPIO =====
static const uint32_t gpio_io_mux_addr[] = {
    [0]  = 0x3FF49044, [1]  = 0x3FF49088, [2]  = 0x3FF49040, [3]  = 0x3FF49084,
    [4]  = 0x3FF49048, [5]  = 0x3FF4906C, [12] = 0x3FF49034, [13] = 0x3FF49038,
    [14] = 0x3FF49030, [15] = 0x3FF4903C, [16] = 0x3FF4904C, [17] = 0x3FF49050,
    [18] = 0x3FF49070, [19] = 0x3FF49074, [21] = 0x3FF4907C, [22] = 0x3FF49080,
    [23] = 0x3FF4908C, [25] = 0x3FF49024, [26] = 0x3FF49028, [27] = 0x3FF4902C,
    [32] = 0x3FF4901C, [33] = 0x3FF49020, [34] = 0x3FF49014, [35] = 0x3FF49018,
    [36] = 0x3FF49004, [37] = 0x3FF49008, [38] = 0x3FF4900C, [39] = 0x3FF49010,
};

// ===== LEDC timer and channel register base =====
#define LEDC_HSTIMER_CONF_REG(n)     (*(volatile uint32_t*)(0x3FF59140 + (n) * 0x8))    // High-speed timer configuration
#define LEDC_HSCH_CONF0_REG(n)       (*(volatile uint32_t*)(0x3FF59000 + (n) * 0x14))   // Channel configuration 0
#define LEDC_HSCH_HPOINT_REG(n)      (*(volatile uint32_t*)(0x3FF59004 + (n) * 0x14))   // High point
#define LEDC_HSCH_DUTY_REG(n)        (*(volatile uint32_t*)(0x3FF59008 + (n) * 0x14))   // PWM duty
#define LEDC_HSCH_CONF1_REG(n)       (*(volatile uint32_t*)(0x3FF5900C + (n) * 0x14))   // Channel configuration 1

// ===== Initialize PWM =====
void pwm_init(uint8_t timer_num, uint8_t channel_num, uint8_t resolution_bits, uint8_t gpio_num, uint32_t freq_hz) {
    // --- Enable LEDC peripheral clock ---
    DPORT_PERIP_CLK_EN_REG |= (1 << 11); // Bit 11: LEDC_EN

    // --- Configure LEDC timer ---
    volatile uint32_t* timer_conf = &LEDC_HSTIMER_CONF_REG(timer_num);

    *timer_conf &= ~(0x1F);                      // Clear previous resolution bits [0:4]
    *timer_conf |= (resolution_bits & 0x1F);     // Set new resolution (max 0x1F)

    // Calculate the clock divider: 80MHz / (frequency * 2^resolution)
    uint32_t divider = 80000000 / (freq_hz * (1 << resolution_bits));

    *timer_conf &= ~(0x3FFFF << 5);              // Clear divider bits [22:5]
    *timer_conf |= (divider << 13);              // Set divider (bits [22:5]), shifted appropriately

    // --- Configure PWM channel ---
    LEDC_HSCH_CONF0_REG(channel_num) &= ~(0b11);             // Clear old timer selection
    LEDC_HSCH_CONF0_REG(channel_num) |= (timer_num & 0x3);   // Select timer (0~3)

    LEDC_HSCH_CONF0_REG(channel_num) |= (1 << 2);            // Enable channel (bit 2 = EN)

    LEDC_HSCH_HPOINT_REG(channel_num) = 1;                   // Set high point to 1

    LEDC_HSCH_DUTY_REG(channel_num) &= ~(0xFFFFFF);          // Clear previous duty
    LEDC_HSCH_DUTY_REG(channel_num) = (20 << 4);             // Set default duty (shifted left 4 bits)

    GPIO_FUNC_OUT_SEL_CFG_REG(gpio_num) = 71 + channel_num; // Route LEDC HS_CHx to GPIO

    if (gpio_num < 32) {
        GPIO_ENABLE_W1TS_REG |= (1 << gpio_num);             // Enable output for GPIO < 32
    } else {
        GPIO_ENABLE1_REG |= (1 << (gpio_num - 32));          // Enable output for GPIO ≥ 32
    }

    // --- Configure IO_MUX for selected GPIO ---
    volatile uint32_t* io_mux_reg = (volatile uint32_t*)gpio_io_mux_addr[gpio_num];
    *io_mux_reg &= ~(0b111 << 12);                           // Clear FUNC field
    *io_mux_reg |= (2 << 12);                                // Set FUNC2 (LEDC high-speed function)

    LEDC_HSCH_CONF1_REG(channel_num) |= (1 << 31);           // Trigger duty update

    // --- Unpause the timer (start it) ---
    *timer_conf &= ~(1 << 23); // Bit 23: PAUSE (write 0 to run)
}

// ===== Update PWM duty cycle at runtime =====
void pwm_set_duty(uint8_t channel_num, uint32_t duty_value) {
    LEDC_HSCH_DUTY_REG(channel_num) = (duty_value << 4);     // Set new duty (shifted left 4 bits)
    LEDC_HSCH_CONF1_REG(channel_num) |= (1 << 31);           // Trigger duty update
}