longfiP.h

#include "longfi.h"
#include "radio/radio.h"

#ifdef __cplusplus
extern "C"
{
#endif

#define LONGFI_NUM_UPLINK_CHANNELS 8

    const uint32_t uplink_channel_map[LONGFI_NUM_UPLINK_CHANNELS] = {916000000,
                                                                     916200000,
                                                                     916400000,
                                                                     916600000,
                                                                     916800000,
                                                                     917000000,
                                                                     917200000,
                                                                     917400000};

#define NUM_SF (4)
    typedef enum
    {
        LongFi_SF7  = 0,
        LongFi_SF8  = 1,
        LongFi_SF9  = 2,
        LongFi_SF10 = 3,
    } LongFiSpreading_t;

    const uint32_t payload_per_fragment[NUM_SF] = {24, 24, 24, 24};

    const uint32_t fragments_per_channel[NUM_SF] = {5, 2, 1, 1};

#define TX_OUTPUT_POWER 22 // dBm

#define LORA_BANDWIDTH                                                         \
    0                              // [0: 125 kHz,
                                   //  1: 250 kHz,
                                   //  2: 500 kHz,
                                   //  3: Reserved]
#define LORA_SPREADING_FACTOR (10) // [SF7..SF12]
#define LORA_CODINGRATE                                                        \
    (1)                          // [1: 4/5,
                                 //  2: 4/6,
                                 //  3: 4/7,
                                 //  4: 4/8]
#define LORA_PREAMBLE_LENGTH (8) // Same for Tx and Rx
#define LORA_SYMBOL_TIMEOUT (5)  // Symbols
#define LORA_FIX_LENGTH_PAYLOAD_ON (false)
#define LORA_IQ_INVERSION_ON (false)

#pragma pack(push, 1)
    // if first byte is 0, is single fragment packet_header
    typedef struct
    {
        uint8_t  packet_id; // 0    must be zero
        uint32_t oui;       // 1:4
        uint16_t device_id; // 5:6
        uint16_t mac;       // 7:8
    } packet_header_t;

    // if second byte is 0, is multi-fragment packet_header
    typedef struct
    {
        uint8_t  packet_id;     // 0    must be non-zero
        uint8_t  fragment_num;  // 1    must be zero (byte)
        uint8_t  num_fragments; // 2    must be non-zero
        uint32_t oui;           // 3:6
        uint16_t device_id;     // 7:8
        uint16_t mac;           // 9:10
    } packet_header_multiple_fragments_t;

    // else (first and second byte, non-zero), is packet fragment
    typedef struct
    {
        uint8_t  packet_id;    // 0    must be non-zero
        uint8_t  fragment_num; // 1    must be non-zero
        uint16_t mac;          // 2:3
    } fragment_header_t;
#pragma pack(pop)

#define RX_TIMEOUT_VALUE 1000
#define BUFFER_SIZE 128 // Define the payload size here

    /*
     *  Functions implemented here that SX1276 will call
     *
     *  As far as I can tell, these are only called from SX1276 when:
     *      LongFi.dio_irq_handles are dispatched
     *      Timeout callbacks are dispatched
     *  With the event refactoring here, these callbacks will only be called
     * from `helium_rf_handle_event`
     */
    void OnTxDone(void);
    void OnRxDone(uint8_t * payload, uint16_t size, int16_t rssi, int8_t snr);
    void OnTxTimeout(void);
    void OnRxTimeout(void);
    void OnRxError(void);

    // Internal events are mapped from SX12xx events
    typedef enum
    {
        InternalEvent_None,
        InternalEvent_TxDone,
        InternalEvent_RxDone,
        InternalEvent_TxTimeout,
        InternalEvent_RxTimeout,
        InternalEvent_RxError,
    } InternalEvent_t;

    typedef struct
    {
        uint8_t spreading_factor;
        void (*dio_irq_handles[NUM_IRQ_HANDLES])();
        RadioEvents_t   radio_events;
        InternalEvent_t cur_event;
        uint8_t *       buffer;
        size_t          buffer_len;
        uint32_t        rx_len;
        uint32_t        tx_cnt;
        uint32_t        tx_len;
    } LongFiInternal_t;

    /*
     * Private helper for handling internal events
     */
    ClientEvent_t _handle_internal_event(LongFi_t * handle);

    /*
     * Private helper for counting bytes
     */
    size_t payload_bytes_in_single_fragment_packet();
    size_t payload_bytes_in_first_fragment_of_many();
    size_t payload_bytes_in_subsequent_fragments();

#ifdef __cplusplus
}
#endif