Pager.h

#if !defined(_RADIOLIB_PAGER_H) && !defined(RADIOLIB_EXCLUDE_PAGER)
#define _RADIOLIB_PAGER_H
 
#include "../../TypeDef.h"
#include "../PhysicalLayer/PhysicalLayer.h"
 
// frequency shift in Hz
#define RADIOLIB_PAGER_FREQ_SHIFT_HZ                            (4500)
 
// supported encoding schemes
#define RADIOLIB_PAGER_ASCII                                    (0)
#define RADIOLIB_PAGER_BCD                                      (1)
 
// preamble length in 32-bit code words
#define RADIOLIB_PAGER_PREAMBLE_LENGTH                          (18)
 
// protocol-specified code words
#define RADIOLIB_PAGER_PREAMBLE_CODE_WORD                       (0xAAAAAAAA)
#define RADIOLIB_PAGER_FRAME_SYNC_CODE_WORD                     (0x7CD215D8)
#define RADIOLIB_PAGER_IDLE_CODE_WORD                           (0x7A89C197)
 
// code word type identification flags
#define RADIOLIB_PAGER_ADDRESS_CODE_WORD                        (0UL)
#define RADIOLIB_PAGER_MESSAGE_CODE_WORD                        (1UL)
 
// length of code word in bits
#define RADIOLIB_PAGER_CODE_WORD_LEN                            (32)
 
// number of message bits in a single code block
#define RADIOLIB_PAGER_ADDRESS_POS                              (13)
#define RADIOLIB_PAGER_FUNC_BITS_POS                            (11)
#define RADIOLIB_PAGER_MESSAGE_BITS_LENGTH                      (20)
#define RADIOLIB_PAGER_MESSAGE_END_POS                          (11)
 
// number of code words in a batch
#define RADIOLIB_PAGER_BATCH_LEN                                (16)
 
// mask for address bits in a single code word
#define RADIOLIB_PAGER_ADDRESS_BITS_MASK                        (0x7FFFE000UL)
 
// mask for function bits in a single code word
#define RADIOLIB_PAGER_FUNCTION_BITS_MASK                       (0x00001800UL)
 
// mask for BCH bits in a single code word
#define RADIOLIB_PAGER_BCH_BITS_MASK                            (0x000007FFUL)
 
// message type functional bits
#define RADIOLIB_PAGER_FUNC_BITS_NUMERIC                        (0b00UL << RADIOLIB_PAGER_FUNC_BITS_POS)
#define RADIOLIB_PAGER_FUNC_BITS_TONE                           (0b01UL << RADIOLIB_PAGER_FUNC_BITS_POS)
#define RADIOLIB_PAGER_FUNC_BITS_ALPHA                          (0b11UL << RADIOLIB_PAGER_FUNC_BITS_POS)
 
// the maximum allowed address (2^22 - 1)
#define RADIOLIB_PAGER_ADDRESS_MAX                              (2097151)
 
// BCH(31, 21) code constants
#define RADIOLIB_PAGER_BCH_M                                    (5)
#define RADIOLIB_PAGER_BCH_N                                    (31)
#define RADIOLIB_PAGER_BCH_K                                    (21)
#define RADIOLIB_PAGER_BCH_D                                    (5)
 
 // BCH(31, 21) primitive polynomial x^5 + x^2 + 1
#define RADIOLIB_PAGER_BCH_PRIMITIVE_POLY                       (0x25)
 
class PagerClient {
  public:
    explicit PagerClient(PhysicalLayer* phy);
 
    // basic methods
 
    int16_t begin(float base, uint16_t speed);
 
    int16_t sendTone(uint32_t addr);
 
    int16_t transmit(String& str, uint32_t addr, uint8_t encoding = RADIOLIB_PAGER_BCD);
 
    int16_t transmit(const char* str, uint32_t addr, uint8_t encoding = RADIOLIB_PAGER_BCD);
 
    int16_t transmit(uint8_t* data, size_t len, uint32_t addr, uint8_t encoding = RADIOLIB_PAGER_BCD);
 
    int16_t startReceive(RADIOLIB_PIN_TYPE pin, uint32_t addr, uint32_t mask = 0xFFFFF);
 
    size_t available();
 
    int16_t readData(String& str, size_t len = 0);
 
    int16_t readData(uint8_t* data, size_t* len);
 
#if !defined(RADIOLIB_GODMODE)
  private:
#endif
    PhysicalLayer* _phy;
 
    float _base;
    float _speed;
    uint32_t _baseRaw;
    uint16_t _shift;
    uint16_t _bitDuration;
    uint32_t _readBatchPos;
    uint32_t _filterAddr;
    uint32_t _filterMask;
 
    // BCH encoder
    int32_t _bchAlphaTo[RADIOLIB_PAGER_BCH_N + 1];
    int32_t _bchIndexOf[RADIOLIB_PAGER_BCH_N + 1];
    int32_t _bchG[RADIOLIB_PAGER_BCH_N - RADIOLIB_PAGER_BCH_K + 1];
 
    void write(uint32_t* data, size_t len);
    void write(uint32_t codeWord);
    uint32_t read();
 
    uint8_t encodeBCD(char c);
    char decodeBCD(uint8_t b);
 
    void encoderInit();
    uint32_t encodeBCH(uint32_t data);
};
 
#endif