src/main/rx/expresslrs_common.h

   1 /*
   2  * This file is part of Cleanflight and Betaflight.
   3  *
   4  * Cleanflight and Betaflight are free software. You can redistribute
   5  * this software and/or modify this software under the terms of the
   6  * GNU General Public License as published by the Free Software
   7  * Foundation, either version 3 of the License, or (at your option)
   8  * any later version.
   9  *
  10  * Cleanflight and Betaflight are distributed in the hope that they
  11  * will be useful, but WITHOUT ANY WARRANTY; without even the implied
  12  * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  13  * See the GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this software.
  17  *
  18  * If not, see <http://www.gnu.org/licenses/>.
  19  */
  20
  21 /*
  22  * Based on https://github.com/ExpressLRS/ExpressLRS
  23  * Thanks to AlessandroAU, original creator of the ExpressLRS project.
  24  */
  25
  26 #pragma once
  27
  28 #include <stdbool.h>
  29 #include <stdint.h>
  30
  31 #include "drivers/io_types.h"
  32 #include "drivers/time.h"
  33
  34 #define ELRS_CRC_LEN 256
  35 #define ELRS_CRC14_POLY 0x2E57
  36
  37 #define ELRS_NR_SEQUENCE_ENTRIES 256
  38
  39 #define ELRS_RX_TX_BUFF_SIZE 8
  40
  41 #define ELRS_TELEMETRY_TYPE_LINK 0x01
  42 #define ELRS_TELEMETRY_TYPE_DATA 0x02
  43 #define ELRS_MSP_BIND 0x09
  44 #define ELRS_MSP_MODEL_ID 0x0A
  45 #define ELRS_MSP_SET_RX_CONFIG 45
  46
  47 #define ELRS_MODELMATCH_MASK 0x3F
  48
  49 #define FREQ_HZ_TO_REG_VAL_900(freq) ((uint32_t)(freq / SX127x_FREQ_STEP))
  50 #define FREQ_HZ_TO_REG_VAL_24(freq) ((uint32_t)(freq / SX1280_FREQ_STEP))
  51
  52 #define ELRS_RATE_MAX 4
  53 #define ELRS_BINDING_RATE_24 3
  54 #define ELRS_BINDING_RATE_900 2
  55
  56 #define ELRS_MAX_CHANNELS 16
  57 #define ELRS_RSSI_CHANNEL 15
  58 #define ELRS_LQ_CHANNEL 14
  59
  60 #define ELRS_CONFIG_CHECK_MS 200
  61 #define ELRS_LINK_STATS_CHECK_MS 100
  62 #define ELRS_CONSIDER_CONNECTION_GOOD_MS 1000
  63
  64 #define ELRS_MODE_CYCLE_MULTIPLIER_SLOW 10
  65
  66 typedef enum {
  67 #ifdef USE_RX_SX127X
  68     AU433,
  69     AU915,
  70     EU433,
  71     EU868,
  72     IN866,
  73     FCC915,
  74 #endif
  75 #ifdef USE_RX_SX1280
  76     ISM2400,
  77 #endif
  78 #if !defined(USE_RX_SX127X) && !defined(USE_RX_SX1280)
  79     NONE,
  80 #endif
  81 } elrsFreqDomain_e;
  82
  83 typedef enum {
  84     SM_HYBRID = 0,
  85     SM_HYBRID_WIDE = 1
  86 } elrsSwitchMode_e;
  87
  88 typedef enum {
  89     TLM_RATIO_NO_TLM = 0,
  90     TLM_RATIO_1_128 = 1,
  91     TLM_RATIO_1_64 = 2,
  92     TLM_RATIO_1_32 = 3,
  93     TLM_RATIO_1_16 = 4,
  94     TLM_RATIO_1_8 = 5,
  95     TLM_RATIO_1_4 = 6,
  96     TLM_RATIO_1_2 = 7,
  97 } elrsTlmRatio_e;
  98
  99 typedef enum {
 100     RATE_500HZ = 0,
 101     RATE_250HZ = 1,
 102     RATE_200HZ = 2,
 103     RATE_150HZ = 3,
 104     RATE_100HZ = 4,
 105     RATE_50HZ = 5,
 106     RATE_25HZ = 6,
 107     RATE_4HZ = 7,
 108 } elrsRfRate_e; // Max value of 16 since only 4 bits have been assigned in the sync package.
 109
 110 typedef struct elrsModSettings_s {
 111     uint8_t index;
 112     elrsRfRate_e enumRate;            // Max value of 16 since only 4 bits have been assigned in the sync package.
 113     uint8_t bw;
 114     uint8_t sf;
 115     uint8_t cr;
 116     uint32_t interval;                  // interval in us seconds that corresponds to that frequency
 117     elrsTlmRatio_e tlmInterval;       // every X packets is a response TLM packet, should be a power of 2
 118     uint8_t fhssHopInterval;            // every X packets we hop to a new frequency. Max value of 16 since only 4 bits have been assigned in the sync package.
 119     uint8_t preambleLen;
 120 } elrsModSettings_t;
 121
 122 typedef struct elrsRfPerfParams_s {
 123     int8_t index;
 124     elrsRfRate_e enumRate;        // Max value of 16 since only 4 bits have been assigned in the sync package.
 125     int32_t sensitivity;            // expected RF sensitivity based on
 126     uint32_t toa;                   // time on air in microseconds
 127     uint32_t disconnectTimeoutMs;   // Time without a packet before receiver goes to disconnected (ms)
 128     uint32_t rxLockTimeoutMs;       // Max time to go from tentative -> connected state on receiver (ms)
 129     uint32_t syncPktIntervalDisconnected; // how often to send the SYNC_PACKET packet (ms) when there is no response from RX
 130     uint32_t syncPktIntervalConnected;    // how often to send the SYNC_PACKET packet (ms) when there we have a connection
 131 } elrsRfPerfParams_t;
 132
 133 typedef bool (*elrsRxInitFnPtr)(IO_t resetPin, IO_t busyPin);
 134 typedef void (*elrsRxConfigFnPtr)(const uint8_t bw, const uint8_t sf, const uint8_t cr, const uint32_t freq, const uint8_t preambleLen, const bool iqInverted);
 135 typedef void (*elrsRxStartReceivingFnPtr)(void);
 136 typedef void (*elrsRxISRFnPtr)(void);
 137 typedef void (*elrsRxHandleFromTockFnPtr)(void);
 138 typedef bool (*elrsRxBusyTimeoutFnPtr)(void);
 139 typedef void (*elrsRxTransmitDataFnPtr)(const uint8_t *data, const uint8_t length);
 140 typedef void (*elrsRxReceiveDataFnPtr)(uint8_t *data, const uint8_t length);
 141 typedef void (*elrsRxgetRfLinkInfoFnPtr)(int8_t *rssi, int8_t *snr);
 142 typedef void (*elrsRxSetFrequencyFnPtr)(const uint32_t freq);
 143 typedef void (*elrsRxHandleFreqCorrectionFnPtr)(int32_t offset, const uint32_t freq);
 144
 145 extern elrsModSettings_t airRateConfig[][ELRS_RATE_MAX];
 146 extern elrsRfPerfParams_t rfPerfConfig[][ELRS_RATE_MAX];
 147
 148 void generateCrc14Table(void);
 149 uint16_t calcCrc14(uint8_t *data, uint8_t len, uint16_t crc);
 150
 151 uint32_t fhssGetInitialFreq(const int32_t freqCorrection);
 152 uint8_t fhssGetNumEntries(void);
 153 uint8_t fhssGetCurrIndex(void);
 154 void fhssSetCurrIndex(const uint8_t value);
 155 uint32_t fhssGetNextFreq(const int32_t freqCorrection);
 156 void fhssGenSequence(const uint8_t UID[], const elrsFreqDomain_e dom);
 157 uint8_t tlmRatioEnumToValue(const elrsTlmRatio_e enumval);
 158 uint16_t rateEnumToHz(const elrsRfRate_e eRate);
 159 uint16_t txPowerIndexToValue(const uint8_t index);
 160
 161 //
 162 // Link Quality
 163 //
 164 void lqReset(void);
 165 void lqNewPeriod(void);
 166 bool lqPeriodIsSet(void);
 167 void lqIncrease(void);
 168 uint8_t lqGet(void);
 169
 170 uint16_t convertSwitch1b(const uint16_t val);
 171 uint16_t convertSwitch3b(const uint16_t val);
 172 uint16_t convertSwitchNb(const uint16_t val, const uint16_t max);
 173 uint16_t convertAnalog(const uint16_t val);
 174 uint8_t hybridWideNonceToSwitchIndex(const uint8_t nonce);