SDK • side-set (pin17) not active not active

Code:

Observing the side-set pin 17 on an oscope reveals that it remains low always. Here the C program and the  associated PIO program.program custom_signal.side_set 1 opt    ; Declare 1 side-set pin and enable OPT.wrap_targetstart:    set y, 31                    ; Initialize loop counter and set sideset pin LOW     pull                        ; Wait for data, keep sideset Low bitloop:    out x, 1                     ; Shift out one bit from OSR    jmp !x bit0                  ; If x is 0, jump to bit0    set pins, 1  side 1 [2]      ; bit is a '1' so short high for 3 cycles; clock goes high     set pins, 0 [4]              ; low for 5 cycles     jmp y--, bitloop side 0      ; loop: get another bit, low for 1 cycle; clock goes low     jmp start                    ; Go to start: pull another word bit0:    set pins, 1  side 1 [5]             ; bit 0 so long high for 6 cycles     set pins, 0  [1]             ; short low for 3 cyles     jmp y--, bitloop side 0      ; Go back to start after bitloop, set sideset LOW .wrap-------- c program ---- below#include "pico/stdlib.h"#include "hardware/pio.h"#include "hardware/gpio.h"#include "custom_signal.pio.h"// Define the pins and hardware configuration#define SET_PIN 16      // SET pin for data output#define SIDE_PIN 17     // Side-set pin#define PIO_BLOCK pio0 #define SM 0  #define CLK_DIV 25000.0fvoid setup_pio_pins(PIO pio, uint sm) {    // Disable state machine before configuration    pio_sm_set_enabled(pio, sm, false);        // Load the PIO program    uint offset = pio_add_program(pio, &custom_signal_program);        // Get default configuration    pio_sm_config config = custom_signal_program_get_default_config(offset);        // Configure clock divider    sm_config_set_clkdiv(&config, CLK_DIV);        // Join FIFOs to increase TX size    sm_config_set_fifo_join(&config, PIO_FIFO_JOIN_TX);        // Initialize GPIO pins for PIO function    gpio_init(SET_PIN);    gpio_init(SIDE_PIN);        // Set GPIO function to PIO0 - CRITICAL FOR PROPER OPERATION    gpio_set_function(SET_PIN, GPIO_FUNC_PIO0);    gpio_set_function(SIDE_PIN, GPIO_FUNC_PIO0);        // Configure SET pin    sm_config_set_set_pins(&config, SET_PIN, 1);        // Configure side-set pin - THIS IS THE CRITICAL PART FOR PIN 17    sm_config_set_sideset_pins(&config, SIDE_PIN);    sm_config_set_sideset(&config, 1, true, false); // 1 pin, optional, no pindirs control        // Set pins as outputs    pio_sm_set_consecutive_pindirs(pio, sm, SET_PIN, 1, true);    pio_sm_set_consecutive_pindirs(pio, sm, SIDE_PIN, 1, true);        // Initialize state machine with configuration    pio_sm_init(pio, sm, offset, &config);        // Set initial pin states    pio_sm_set_pins_with_mask(pio, sm, 0, (1u << SET_PIN));    pio_sm_set_pins_with_mask(pio, sm, 0, (1u << SIDE_PIN));        // Enable the state machine    pio_sm_set_enabled(pio, sm, true);        // For debugging:    printf("PIO pins configured - SET: %d, SIDE: %d\n", SET_PIN, SIDE_PIN);}int main() {    // Initialize standard library    stdio_init_all();    sleep_ms(500); // Allow time for USB serial to initialize        printf("Initializing PIO side-set example\n");        // Setup PIO with correct pins    setup_pio_pins(PIO_BLOCK, SM);        uint32_t count = 0;        // Main loop - send alternating patterns    while (true) {        // Alternate between all 0s and all 1s        uint32_t data = (count++ % 2) ? 0xFFFFFFFF : 0x00000000;                // Send data to PIO        if (!pio_sm_is_tx_fifo_full(PIO_BLOCK, SM)) {            pio_sm_put_blocking(PIO_BLOCK, SM, data);                        // Debug output occasionally            if (count % 1000 == 0) {                printf("Sent data: 0x%08lx (count: %lu)\n",                       (unsigned long)data, (unsigned long)count);            }        }                sleep_ms(5); // Small delay to prevent overwhelming CPU    }        return 0;}