test

Dependents:   Telemetria_RX_SD_GPS_copy Telemetria_RX_SD_GPS Telemetria_TX Telemetria_TX ... more

Embed: (wiki syntax)

« Back to documentation index

Show/hide line numbers sx1276.h Source File

sx1276.h

00001 /*
00002  / _____)             _              | |
00003 ( (____  _____ ____ _| |_ _____  ____| |__
00004  \____ \| ___ |    (_   _) ___ |/ ___)  _ \
00005  _____) ) ____| | | || |_| ____( (___| | | |
00006 (______/|_____)_|_|_| \__)_____)\____)_| |_|
00007     (C) 2014 Semtech
00008 
00009 Description: Actual implementation of a SX1276 radio, inherits Radio
00010 
00011 License: Revised BSD License, see LICENSE.TXT file include in the project
00012 
00013 Maintainers: Miguel Luis, Gregory Cristian and Nicolas Huguenin
00014 */
00015 
00016 /*
00017  * additional development to make it more generic across multiple OS versions
00018  * (c) 2017 Helmut Tschemernjak
00019  * 30826 Garbsen (Hannover) Germany
00020  */
00021 
00022 #ifndef __SX1276_H__
00023 #define __SX1276_H__
00024 
00025 #include "radio.h"
00026 #include "sx1276Regs-Fsk.h"
00027 #include "sx1276Regs-LoRa.h"
00028 
00029 
00030 
00031 /*!
00032  * Radio wake-up time from sleep
00033  */
00034 #define RADIO_WAKEUP_TIME                           1 // [ms]
00035 
00036 /*!
00037  * Sync word for Private LoRa networks
00038  */
00039 #define LORA_MAC_PRIVATE_SYNCWORD                   0x12
00040 
00041 /*!
00042  * Sync word for Public LoRa networks
00043  */
00044 #define LORA_MAC_PUBLIC_SYNCWORD                    0x34
00045 
00046 
00047 /*!
00048  * SX1276 definitions
00049  */
00050 #define XTAL_FREQ                                   32000000
00051 #define FREQ_STEP                                   61.03515625
00052 
00053 #define RX_BUFFER_SIZE                              256
00054 
00055 /*!
00056  * Constant values need to compute the RSSI value
00057  */
00058 #define RSSI_OFFSET_LF                              -164.0
00059 #define RSSI_OFFSET_HF                              -157.0
00060 
00061 #define RF_MID_BAND_THRESH                          525000000
00062 
00063 
00064 
00065 
00066 /*!
00067  * Type of the supported board. [SX1276MB1MAS / SX1276MB1LAS]
00068  */
00069 typedef enum BoardType
00070 {
00071     SX1276MB1MAS = 0,
00072     SX1276MB1LAS,
00073     RFM95_SX1276,
00074     MURATA_SX1276,
00075     UNKNOWN
00076 }BoardType_t;
00077 
00078 
00079 typedef enum {
00080     LORA_SF6 =  6,  //   64 chips/symbol, SF6 requires an TCXO!
00081     LORA_SF7 =  7,  //  128 chips/symbol
00082     LORA_SF8 =  8,  //  256 chips/symbol
00083     LORA_SF9 =  9,  //  512 chips/symbol
00084     LORA_SF10 = 10, // 1024 chips/symbol
00085     LORA_SF11 = 11, // 2048 chips/symbol
00086     LORA_SF12 = 12, // 4096 chips/symbol
00087 } lora_spreading_factor_t;
00088 
00089 
00090 typedef enum {  // cyclic error coding to perform forward error detection and correction
00091     LORA_ERROR_CODING_RATE_4_5 = 1,   // 1.25x overhead
00092     LORA_ERROR_CODING_RATE_4_6 = 2,   // 1.50x overhead
00093     LORA_ERROR_CODING_RATE_4_7 = 3,   // 1.75x overhead
00094     LORA_ERROR_CODING_RATE_4_8 = 4,   // 2.00x overhead
00095 } lora_coding_rate_t;
00096 
00097 
00098 typedef enum {
00099     RF_FREQUENCY_868_0 = 868000000, // Hz
00100     RF_FREQUENCY_868_1 = 868100000, // Hz
00101     RF_FREQUENCY_868_3 = 868300000, // Hz
00102     RF_FREQUENCY_868_5 = 868500000, // Hz
00103     RF_FREQUENCY_915_0 = 915000000, // Hz
00104 } rf_frequency_t;
00105 
00106 
00107 
00108 /*!
00109  * Actual implementation of a SX1276 radio, inherits Radio
00110  */
00111 class SX1276  : public Radio 
00112 {
00113 protected:
00114 
00115     bool isRadioActive;
00116 
00117     BoardType_t boardConnected; //1 = SX1276MB1LAS; 0 = SX1276MB1MAS
00118 
00119     uint8_t *rxtxBuffer;
00120     
00121     /*!
00122      * Hardware IO IRQ callback function definition
00123      */
00124     typedef void ( SX1276 ::*DioIrqHandler  )( void );
00125 
00126     /*!
00127      * Hardware DIO IRQ functions
00128      */
00129     DioIrqHandler  *dioIrq ;
00130 
00131 
00132 
00133     RadioSettings_t  settings;
00134 
00135     /*!
00136      * FSK bandwidth definition
00137      */
00138     struct BandwidthMap  {
00139         uint32_t bandwidth;
00140         uint8_t  RegValue;
00141     };
00142     static const struct BandwidthMap  FskBandwidths[];
00143     static const struct BandwidthMap  LoRaBandwidths[];
00144     
00145 protected:
00146 
00147     /*!
00148     * Performs the Rx chain calibration for LF and HF bands
00149     * \remark Must be called just after the reset so all registers are at their
00150     *         default values
00151     */
00152     void RxChainCalibration ( void );
00153 
00154 public:
00155     SX1276 ( RadioEvents_t *events);
00156     virtual ~SX1276 ( );
00157     
00158     
00159     
00160     
00161     //-------------------------------------------------------------------------
00162     //                        Redefined Radio functions
00163     //-------------------------------------------------------------------------
00164     /*!
00165      * @brief Return current radio status, returns true if a radios has been found.
00166      *
00167      * @param [IN] events Structure containing the driver callback functions
00168      */
00169     virtual bool Init( RadioEvents_t *events );
00170 
00171     /*!
00172      *  @brief Initializes the radio registers
00173      */
00174     virtual void RadioRegistersInit(void);
00175 
00176     /*!
00177      * Return current radio status
00178      *
00179      * @param status Radio status. [RF_IDLE, RX_RUNNING, TX_RUNNING, CAD_RUNNING]
00180      */
00181     virtual RadioState GetStatus ( void ); 
00182 
00183     /*!
00184      * @brief Configures the SX1276 with the given modem
00185      *
00186      * @param [IN] modem Modem to be used [0: FSK, 1: LoRa] 
00187      */
00188     virtual void SetModem( RadioModems_t modem );
00189 
00190     /*!
00191      * @brief Sets the channel frequency
00192      *
00193      * @param [IN] freq         Channel RF frequency
00194      */
00195     virtual void SetChannel( uint32_t freq );
00196 
00197     /*!
00198      * @brief Sets the channels configuration
00199      *
00200      * @param [IN] modem      Radio modem to be used [0: FSK, 1: LoRa]
00201      * @param [IN] freq       Channel RF frequency
00202      * @param [IN] rssiThresh RSSI threshold
00203      *
00204      * @retval isFree         [true: Channel is free, false: Channel is not free]
00205      */
00206     virtual bool IsChannelFree( RadioModems_t modem, uint32_t freq, int16_t rssiThresh );
00207 
00208     /*!
00209      * @brief Generates a 32 bits random value based on the RSSI readings
00210      *
00211      * \remark This function sets the radio in LoRa modem mode and disables
00212      *         all interrupts.
00213      *         After calling this function either Radio.SetRxConfig or
00214      *         Radio.SetTxConfig functions must be called.
00215      *
00216      * @retval randomValue    32 bits random value
00217      */
00218     virtual uint32_t Random( void );
00219 
00220     /*!
00221      * @brief Sets the reception parameters
00222      *
00223      * @param [IN] modem        Radio modem to be used [0: FSK, 1: LoRa]
00224      * @param [IN] bandwidth    Sets the bandwidth
00225      *                          FSK : >= 2600 and <= 250000 Hz
00226      *                          LoRa: [0: 125 kHz, 1: 250 kHz,
00227      *                                 2: 500 kHz, 3: Reserved]
00228      * @param [IN] datarate     Sets the Datarate
00229      *                          FSK : 600..300000 bits/s
00230      *                          LoRa: [6: 64, 7: 128, 8: 256, 9: 512,
00231      *                                10: 1024, 11: 2048, 12: 4096  chips]
00232      * @param [IN] coderate     Sets the coding rate ( LoRa only )
00233      *                          FSK : N/A ( set to 0 )
00234      *                          LoRa: [1: 4/5, 2: 4/6, 3: 4/7, 4: 4/8]
00235      * @param [IN] bandwidthAfc Sets the AFC Bandwidth ( FSK only )
00236      *                          FSK : >= 2600 and <= 250000 Hz
00237      *                          LoRa: N/A ( set to 0 )
00238      * @param [IN] preambleLen  Sets the Preamble length ( LoRa only )
00239      *                          FSK : N/A ( set to 0 )
00240      *                          LoRa: Length in symbols ( the hardware adds 4 more symbols )
00241      * @param [IN] symbTimeout  Sets the RxSingle timeout value
00242      *                          FSK : timeout number of bytes
00243      *                          LoRa: timeout in symbols
00244      * @param [IN] fixLen       Fixed length packets [0: variable, 1: fixed]
00245      * @param [IN] payloadLen   Sets payload length when fixed lenght is used
00246      * @param [IN] crcOn        Enables/Disables the CRC [0: OFF, 1: ON]
00247      * @param [IN] freqHopOn    Enables disables the intra-packet frequency hopping  [0: OFF, 1: ON] (LoRa only)
00248      * @param [IN] hopPeriod    Number of symbols bewteen each hop (LoRa only)
00249      * @param [IN] iqInverted   Inverts IQ signals ( LoRa only )
00250      *                          FSK : N/A ( set to 0 )
00251      *                          LoRa: [0: not inverted, 1: inverted]
00252      * @param [IN] rxContinuous Sets the reception in continuous mode
00253      *                          [false: single mode, true: continuous mode]
00254      */
00255     virtual void SetRxConfig ( RadioModems_t modem, uint32_t bandwidth,
00256                                uint32_t datarate, uint8_t coderate,
00257                                uint32_t bandwidthAfc, uint16_t preambleLen,
00258                                uint16_t symbTimeout, bool fixLen,
00259                                uint8_t payloadLen,
00260                                bool crcOn, bool freqHopOn, uint8_t hopPeriod,
00261                                bool iqInverted, bool rxContinuous );
00262 
00263     /*!
00264      * @brief Sets the transmission parameters
00265      *
00266      * @param [IN] modem        Radio modem to be used [0: FSK, 1: LoRa]
00267      * @param [IN] power        Sets the output power [dBm]
00268      * @param [IN] fdev         Sets the frequency deviation ( FSK only )
00269      *                          FSK : [Hz]
00270      *                          LoRa: 0
00271      * @param [IN] bandwidth    Sets the bandwidth ( LoRa only )
00272      *                          FSK : 0
00273      *                          LoRa: [0: 125 kHz, 1: 250 kHz,
00274      *                                 2: 500 kHz, 3: Reserved]
00275      * @param [IN] datarate     Sets the Datarate
00276      *                          FSK : 600..300000 bits/s
00277      *                          LoRa: [6: 64, 7: 128, 8: 256, 9: 512,
00278      *                                10: 1024, 11: 2048, 12: 4096  chips]
00279      * @param [IN] coderate     Sets the coding rate ( LoRa only )
00280      *                          FSK : N/A ( set to 0 )
00281      *                          LoRa: [1: 4/5, 2: 4/6, 3: 4/7, 4: 4/8]
00282      * @param [IN] preambleLen  Sets the preamble length
00283      * @param [IN] fixLen       Fixed length packets [0: variable, 1: fixed]
00284      * @param [IN] crcOn        Enables disables the CRC [0: OFF, 1: ON]
00285      * @param [IN] freqHopOn    Enables disables the intra-packet frequency hopping  [0: OFF, 1: ON] (LoRa only)
00286      * @param [IN] hopPeriod    Number of symbols bewteen each hop (LoRa only)
00287      * @param [IN] iqInverted   Inverts IQ signals ( LoRa only )
00288      *                          FSK : N/A ( set to 0 )
00289      *                          LoRa: [0: not inverted, 1: inverted]
00290      * @param [IN] timeout      Transmission timeout [ms]
00291      */
00292     virtual void SetTxConfig( RadioModems_t modem, int8_t power, uint32_t fdev,
00293                               uint32_t bandwidth, uint32_t datarate,
00294                               uint8_t coderate, uint16_t preambleLen,
00295                               bool fixLen, bool crcOn, bool freqHopOn,
00296                               uint8_t hopPeriod, bool iqInverted, uint32_t timeout );
00297 
00298     
00299     /*!
00300      * @brief Checks if the given RF frequency is supported by the hardware
00301      *
00302      * @param [IN] frequency RF frequency to be checked
00303      * @retval isSupported [true: supported, false: unsupported]
00304      */
00305     virtual bool CheckRfFrequency( uint32_t frequency ) = 0;
00306     
00307     /*!
00308      * @brief Computes the packet time on air for the given payload
00309      *
00310      * \Remark Can only be called once SetRxConfig or SetTxConfig have been called
00311      *
00312      * @param [IN] modem      Radio modem to be used [0: FSK, 1: LoRa]
00313      * @param [IN] pktLen     Packet payload length
00314      *
00315      * @retval airTime        Computed airTime for the given packet payload length
00316      */
00317     virtual uint32_t TimeOnAir ( RadioModems_t modem, int16_t pktLen );
00318 
00319     /*!
00320      * @brief Sends the buffer of size. Prepares the packet to be sent and sets
00321      *        the radio in transmission
00322      *
00323      * @param [IN]: buffer     Buffer pointer
00324      * @param [IN]: size       Buffer size
00325      * @param [IN]: buffer     Header pointer
00326      * @param [IN]: size       Header size
00327      */
00328     virtual void Send(void *buffer, int16_t size, void *header = NULL, int16_t hsize = 0);
00329 
00330     /*!
00331      * @brief Sets the radio in sleep mode
00332      */
00333     virtual void Sleep( void );
00334     
00335     /*!
00336      * @brief Sets the radio in standby mode
00337      */
00338     virtual void Standby( void );
00339     
00340     /*!
00341      * @brief Sets the radio in CAD mode
00342      */
00343     virtual void StartCad( void );
00344 
00345     /*!
00346      * @brief Sets the radio in reception mode for the given time
00347      * @param [IN] timeout Reception timeout [ms]
00348      *                     [0: continuous, others timeout]
00349      */
00350     virtual void Rx( uint32_t timeout );
00351     
00352     /*!
00353      * @brief Check is radio receives a signal
00354      */
00355     virtual bool RxSignalPending();
00356 
00357 
00358     /*!
00359      * @brief Sets the radio in transmission mode for the given time
00360      * @param [IN] timeout Transmission timeout [ms]
00361      *                     [0: continuous, others timeout]
00362      */
00363     virtual void Tx( uint32_t timeout );
00364 
00365     /*!
00366      * @brief Sets the radio in continuous wave transmission mode
00367      *
00368      * @param [IN]: freq       Channel RF frequency
00369      * @param [IN]: power      Sets the output power [dBm]
00370      * @param [IN]: time       Transmission mode timeout [s]
00371      */
00372 
00373     virtual void SetTxContinuousWave( uint32_t freq, int8_t power, uint16_t time );
00374 
00375     /*!
00376      * @brief Returns the maximal transfer unit for a given modem
00377      *
00378      * @retval MTU size in bytes
00379      */
00380     virtual int16_t MaxMTUSize( RadioModems_t modem );
00381     
00382     /*!
00383      * @brief Reads the current RSSI value
00384      *
00385      * @retval rssiValue Current RSSI value in [dBm]
00386      */
00387     virtual int16_t GetRssi ( RadioModems_t modem );
00388     
00389     /*!
00390      * @brief Reads the current frequency error
00391      *
00392      * @retval frequency error value in [Hz]
00393      */
00394     virtual int32_t GetFrequencyError( RadioModems_t modem );
00395     
00396     /*!
00397      * @brief Writes the radio register at the specified address
00398      *
00399      * @param [IN]: addr Register address
00400      * @param [IN]: data New register value
00401      */
00402     virtual void Write ( uint8_t addr, uint8_t data ) = 0;
00403 
00404     /*!
00405      * @brief Reads the radio register at the specified address
00406      *
00407      * @param [IN]: addr Register address
00408      * @retval data Register value
00409      */
00410     virtual uint8_t Read ( uint8_t addr ) = 0;
00411 
00412     /*!
00413      * @brief Writes multiple radio registers starting at address
00414      *
00415      * @param [IN] addr   First Radio register address
00416      * @param [IN] buffer Buffer containing the new register's values
00417      * @param [IN] size   Number of registers to be written
00418      */
00419     virtual void Write( uint8_t addr, void *buffer, uint8_t size ) = 0;
00420 
00421     /*!
00422      * @brief Reads multiple radio registers starting at address
00423      *
00424      * @param [IN] addr First Radio register address
00425      * @param [OUT] buffer Buffer where to copy the registers data
00426      * @param [IN] size Number of registers to be read
00427      */
00428     virtual void Read ( uint8_t addr, void *buffer, uint8_t size ) = 0;
00429 
00430     /*!
00431      * @brief Writes the buffer contents to the SX1276 FIFO
00432      *
00433      * @param [IN] buffer Buffer containing data to be put on the FIFO.
00434      * @param [IN] size Number of bytes to be written to the FIFO
00435      */
00436     virtual void WriteFifo( void *buffer, uint8_t size ) = 0;
00437 
00438     /*!
00439      * @brief Reads the contents of the SX1276 FIFO
00440      *
00441      * @param [OUT] buffer Buffer where to copy the FIFO read data.
00442      * @param [IN] size Number of bytes to be read from the FIFO
00443      */
00444     virtual void ReadFifo( void *buffer, uint8_t size ) = 0;
00445     /*!
00446      * @brief Resets the SX1276
00447      */
00448     virtual void Reset( void ) = 0;
00449 
00450     /*!
00451      * @brief Sets the maximum payload length.
00452      *
00453      * @param [IN] modem      Radio modem to be used [0: FSK, 1: LoRa]
00454      * @param [IN] max        Maximum payload length in bytes
00455      */
00456     virtual void SetMaxPayloadLength( RadioModems_t modem, uint8_t max );
00457 
00458     /*!
00459      * \brief Sets the network to public or private. Updates the sync byte.
00460      *
00461      * \remark Applies to LoRa modem only
00462      *
00463      * \param [IN] enable if true, it enables a public network
00464      */
00465     virtual void SetPublicNetwork( bool enable );
00466 
00467     /*!
00468      * @brief Sets the radio output power.
00469      *
00470      * @param [IN] power Sets the RF output power
00471      */
00472     virtual void SetRfTxPower( int8_t power ) = 0;
00473     
00474     //-------------------------------------------------------------------------
00475     //                        Board relative functions
00476     //-------------------------------------------------------------------------
00477     /*!
00478      * Radio registers definition
00479      */
00480     struct RadioRegisters  {
00481         ModemType   Modem;
00482         uint8_t     Addr;
00483         uint8_t     Value;
00484     };
00485     
00486     
00487     static const struct RadioRegisters  RadioRegsInit[];
00488 
00489     typedef enum {
00490         RXTimeoutTimer,
00491         TXTimeoutTimer,
00492         RXTimeoutSyncWordTimer
00493     } TimeoutTimer_t;
00494 
00495 
00496 protected:
00497     /*!
00498      * @brief Initializes the radio I/Os pins interface
00499      */
00500     virtual void IoInit( void ) = 0;
00501     
00502     /*!
00503      * @brief Initializes the radio SPI
00504      */
00505     virtual void SpiInit( void ) = 0;
00506 
00507     /*!
00508      * @brief Initializes DIO IRQ handlers
00509      *
00510      * @param [IN] irqHandlers Array containing the IRQ callback functions
00511      */
00512     virtual void IoIrqInit( DioIrqHandler  *irqHandlers ) = 0;
00513 
00514     /*!
00515      * @brief De-initializes the radio I/Os pins interface. 
00516      *
00517      * \remark Useful when going in MCU lowpower modes
00518      */
00519     virtual void IoDeInit( void ) = 0;
00520 
00521     /*!
00522      * @brief Gets the board PA selection configuration
00523      *
00524      * @param [IN] channel Channel frequency in Hz
00525      * @retval PaSelect RegPaConfig PaSelect value
00526      */
00527     virtual uint8_t GetPaSelect( uint32_t channel ) = 0;
00528 
00529     /*!
00530      * @brief Set the RF Switch I/Os pins in Low Power mode
00531      *
00532      * @param [IN] status enable or disable
00533      */
00534     virtual void SetAntSwLowPower( bool status ) = 0;
00535 
00536     /*!
00537      * @brief Initializes the RF Switch I/Os pins interface
00538      */
00539     virtual void AntSwInit( void ) = 0;
00540 
00541     /*!
00542      * @brief De-initializes the RF Switch I/Os pins interface 
00543      *
00544      * \remark Needed to decrease the power consumption in MCU lowpower modes
00545      */
00546     virtual void AntSwDeInit( void ) = 0;
00547 
00548     /*!
00549      * @brief Controls the antenna switch if necessary.
00550      *
00551      * \remark see errata note
00552      *
00553      * @param [IN] opMode Current radio operating mode
00554      */
00555     virtual void SetAntSw( uint8_t opMode ) = 0;
00556     
00557     typedef void ( SX1276 ::*timeoutFuncPtr)( void );
00558     
00559     
00560     /*
00561      * The the Timeout for a given Timer.
00562      */
00563     virtual void SetTimeout(TimeoutTimer_t timer, timeoutFuncPtr, int timeout_ms = 0) = 0;
00564     
00565     /*
00566      * A simple ms sleep
00567      */
00568     virtual void Sleep_ms(int ms) = 0;
00569 
00570 protected:
00571 
00572     /*!
00573      * @brief Sets the SX1276 operating mode
00574      *
00575      * @param [IN] opMode New operating mode
00576      */
00577     virtual void SetOpMode( uint8_t opMode );
00578 
00579     /*
00580      * SX1276 DIO IRQ callback functions prototype
00581      */
00582 
00583     /*!
00584      * @brief DIO 0 IRQ callback
00585      */
00586     virtual void OnDio0Irq( void );
00587 
00588     /*!
00589      * @brief DIO 1 IRQ callback
00590      */
00591     virtual void OnDio1Irq( void );
00592 
00593     /*!
00594      * @brief DIO 2 IRQ callback
00595      */
00596     virtual void OnDio2Irq( void );
00597 
00598     /*!
00599      * @brief DIO 3 IRQ callback
00600      */
00601     virtual void OnDio3Irq( void );
00602 
00603     /*!
00604      * @brief DIO 4 IRQ callback
00605      */
00606     virtual void OnDio4Irq( void );
00607 
00608     /*!
00609      * @brief DIO 5 IRQ callback
00610      */
00611     virtual void OnDio5Irq( void );
00612 
00613     /*!
00614      * @brief Tx & Rx timeout timer callback
00615      */
00616     virtual void OnTimeoutIrq( void );
00617 
00618     /*!
00619      * Returns the known FSK bandwidth registers value
00620      *
00621      * \param [IN] bandwidth Bandwidth value in Hz
00622      * \retval regValue Bandwidth register value.
00623      */
00624     static uint8_t GetFskBandwidthRegValue ( uint32_t bandwidth );
00625 
00626     static uint8_t GetLoRaBandwidthRegValue ( uint32_t bandwidth );
00627     
00628     enum {
00629         LORA_BANKWIDTH_7kHz  = 0, //  7.8 kHz requires TCXO
00630         LORA_BANKWIDTH_10kHz = 1, // 10.4 kHz requires TCXO
00631         LORA_BANKWIDTH_15kHz = 2, // 15.6 kHz requires TCXO
00632         LORA_BANKWIDTH_20kHz = 3, // 20.8 kHz requires TCXO
00633         LORA_BANKWIDTH_31kHz = 4, // 31.2 kHz requires TCXO
00634         LORA_BANKWIDTH_41kHz = 5, // 41.4 kHz requires TCXO
00635         LORA_BANKWIDTH_62kHz = 6, // 62.5 kHz requires TCXO
00636         LORA_BANKWIDTH_125kHz = 7,
00637         LORA_BANKWIDTH_250kHz = 8,
00638         LORA_BANKWIDTH_500kHz = 9,
00639         LORA_BANKWIDTH_RESERVED = 10,
00640     };
00641 };
00642 
00643 #endif // __SX1276_H__