Wiegand.h

#ifndef WIEGAND_H #define WIEGAND_H #include <stdint.h> #include <stdbool.h>

bool validate_26bit(uint32_t raw) uint8_t even_parity = parity_even((raw >> 25) & 0x7F); // Bits 1..13? uint8_t odd_parity = parity_odd((raw >> 1) & 0x3FFF); // Bits 14..25? return (even_parity == ((raw >> 25) & 1)) && (odd_parity == ((raw >> 0) & 1));

// Configuration structure typedef struct uint8_t pin_d0; uint8_t pin_d1; uint32_t bit_timeout_us; // Max gap between bits (e.g., 2500) uint32_t packet_timeout_us; // Gap to finalize packet (e.g., 15000) bool pullup_enable; // Use internal pullups? wiegand_config_t; wiegand.h

// Public API void wiegand_init(const wiegand_config_t *config); void wiegand_set_callback(wiegand_callback_t cb); void wiegand_reset(void); bool wiegand_available(void); uint32_t wiegand_get_facility(void); uint32_t wiegand_get_card(void); int wiegand_get_bit_count(void);

void IRAM_ATTR on_d1_falling() record_bit(1); #ifndef WIEGAND_H #define WIEGAND_H #include &lt;stdint

// Callback type for completed card reads typedef void (*wiegand_callback_t)(uint32_t facility_code, uint32_t card_number, int bits_received);

while (1) vTaskDelay(pdMS_TO_TICKS(1000)); void app_main() wiegand_config_t cfg =

#endif // WIEGAND_H 1. Interrupt‑Driven Bit Capture The only reliable way to read Wiegand is via edge-triggered interrupts on the D0 and D1 pins. Polling will miss microsecond pulses.

void app_main() wiegand_config_t cfg = .pin_d0 = GPIO_NUM_4, .pin_d1 = GPIO_NUM_5, .bit_timeout_us = 2500, .packet_timeout_us = 15000, .pullup_enable = true ; wiegand_init(&cfg); wiegand_set_callback(card_received);

// Example ISR (pseudo-code) void IRAM_ATTR on_d0_falling() record_bit(0);