TMRh20 ported to MBED

Fork of TMRh20 by BME SmartLab

Revision:
0:163155b607df
Child:
1:8f889354678f
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/RF24.h	Thu Mar 10 14:40:30 2016 +0000
@@ -0,0 +1,1097 @@
+/*
+ Copyright (C) 2011 J. Coliz <maniacbug@ymail.com>
+
+ This program is free software; you can redistribute it and/or
+ modify it under the terms of the GNU General Public License
+ version 2 as published by the Free Software Foundation.
+ */
+
+/**
+ * @file RF24.h
+ *
+ * Class declaration for RF24 and helper enums
+ */
+
+#ifndef __RF24_H__
+#define __RF24_H__
+
+#include "mbed.h"
+#include "RF24_config.h"
+
+/**
+ * Power Amplifier level.
+ *
+ * For use with setPALevel()
+ */
+typedef enum { RF24_PA_MIN = 0,RF24_PA_LOW, RF24_PA_HIGH, RF24_PA_MAX, RF24_PA_ERROR } rf24_pa_dbm_e ;
+
+/**
+ * Data rate.  How fast data moves through the air.
+ *
+ * For use with setDataRate()
+ */
+typedef enum { RF24_1MBPS = 0, RF24_2MBPS, RF24_250KBPS } rf24_datarate_e;
+
+/**
+ * CRC Length.  How big (if any) of a CRC is included.
+ *
+ * For use with setCRCLength()
+ */
+typedef enum { RF24_CRC_DISABLED = 0, RF24_CRC_8, RF24_CRC_16 } rf24_crclength_e;
+
+/**
+ * Driver for nRF24L01(+) 2.4GHz Wireless Transceiver
+ */
+
+class RF24
+{
+private:
+
+    SPI spi;
+
+    DigitalOut ce_pin; /**< "Chip Enable" pin, activates the RX or TX role */
+    DigitalOut csn_pin; /**< SPI Chip select */
+    uint16_t spi_speed; /**< SPI Bus Speed */
+
+    uint8_t spi_rxbuff[32+1] ; //SPI receive buffer (payload max 32 bytes)
+    uint8_t spi_txbuff[32+1] ; //SPI transmit buffer (payload max 32 bytes + 1 byte for the command)
+
+    bool p_variant; /* False for RF24L01 and true for RF24L01P */
+    uint8_t payload_size; /**< Fixed size of payloads */
+    bool dynamic_payloads_enabled; /**< Whether dynamic payloads are enabled. */
+    uint8_t pipe0_reading_address[5]; /**< Last address set on pipe 0 for reading. */
+    uint8_t addr_width; /**< The address width to use - 3,4 or 5 bytes. */
+    uint32_t txRxDelay; /**< Var for adjusting delays depending on datarate */
+
+    Timer mainTimer;
+
+
+protected:
+    /**
+     * SPI transactions
+     *
+     * Common code for SPI transactions including CSN toggle
+     *
+     */
+    inline void beginTransaction();
+
+    inline void endTransaction();
+
+public:
+
+    /**
+     * @name Primary public interface
+     *
+     *  These are the main methods you need to operate the chip
+     */
+    /**@{*/
+
+    /**
+     * Arduino Constructor
+     *
+     * Creates a new instance of this driver.  Before using, you create an instance
+     * and send in the unique pins that this chip is connected to.
+     *
+     * @param _cepin The pin attached to Chip Enable on the RF module
+     * @param _cspin The pin attached to Chip Select
+     */
+    RF24(PinName mosi, PinName miso, PinName sck, PinName _cepin, PinName _cspin);
+
+    virtual ~RF24() {};
+
+    /**
+     * Begin operation of the chip
+     *
+     * Call this in setup(), before calling any other methods.
+     * @code radio.begin() @endcode
+     */
+    bool begin(void);
+
+    /**
+     * Start listening on the pipes opened for reading.
+     *
+     * 1. Be sure to call openReadingPipe() first.
+     * 2. Do not call write() while in this mode, without first calling stopListening().
+     * 3. Call available() to check for incoming traffic, and read() to get it.
+     *
+     * @code
+     * Open reading pipe 1 using address CCCECCCECC
+     *
+     * byte address[] = { 0xCC,0xCE,0xCC,0xCE,0xCC };
+     * radio.openReadingPipe(1,address);
+     * radio.startListening();
+     * @endcode
+     */
+    void startListening(void);
+
+    /**
+     * Stop listening for incoming messages, and switch to transmit mode.
+     *
+     * Do this before calling write().
+     * @code
+     * radio.stopListening();
+     * radio.write(&data,sizeof(data));
+     * @endcode
+     */
+    void stopListening(void);
+
+    /**
+     * Check whether there are bytes available to be read
+     * @code
+     * if(radio.available()){
+     *   radio.read(&data,sizeof(data));
+     * }
+     * @endcode
+     * @return True if there is a payload available, false if none is
+     */
+    bool available(void);
+
+    /**
+     * Read the available payload
+     *
+     * The size of data read is the fixed payload size, see getPayloadSize()
+     *
+     * @note I specifically chose 'void*' as a data type to make it easier
+     * for beginners to use.  No casting needed.
+     *
+     * @note No longer boolean. Use available to determine if packets are
+     * available. Interrupt flags are now cleared during reads instead of
+     * when calling available().
+     *
+     * @param buf Pointer to a buffer where the data should be written
+     * @param len Maximum number of bytes to read into the buffer
+     *
+     * @code
+     * if(radio.available()){
+     *   radio.read(&data,sizeof(data));
+     * }
+     * @endcode
+     * @return No return value. Use available().
+     */
+    void read( void* buf, uint8_t len );
+
+    /**
+     * Be sure to call openWritingPipe() first to set the destination
+     * of where to write to.
+     *
+     * This blocks until the message is successfully acknowledged by
+     * the receiver or the timeout/retransmit maxima are reached.  In
+     * the current configuration, the max delay here is 60-70ms.
+     *
+     * The maximum size of data written is the fixed payload size, see
+     * getPayloadSize().  However, you can write less, and the remainder
+     * will just be filled with zeroes.
+     *
+     * TX/RX/RT interrupt flags will be cleared every time write is called
+     *
+     * @param buf Pointer to the data to be sent
+     * @param len Number of bytes to be sent
+     *
+     * @code
+     * radio.stopListening();
+     * radio.write(&data,sizeof(data));
+     * @endcode
+     * @return True if the payload was delivered successfully false if not
+     */
+    bool write( const void* buf, uint8_t len );
+
+    /**
+     * New: Open a pipe for writing via byte array. Old addressing format retained
+     * for compatibility.
+     *
+     * Only one writing pipe can be open at once, but you can change the address
+     * you'll write to. Call stopListening() first.
+     *
+     * Addresses are assigned via a byte array, default is 5 byte address length
+    s   *
+     * @code
+     *   uint8_t addresses[][6] = {"1Node","2Node"};
+     *   radio.openWritingPipe(addresses[0]);
+     * @endcode
+     * @code
+     *  uint8_t address[] = { 0xCC,0xCE,0xCC,0xCE,0xCC };
+     *  radio.openWritingPipe(address);
+     *  address[0] = 0x33;
+     *  radio.openReadingPipe(1,address);
+     * @endcode
+     * @see setAddressWidth
+     *
+     * @param address The address of the pipe to open. Coordinate these pipe
+     * addresses amongst nodes on the network.
+     */
+
+    void openWritingPipe(const uint8_t *address);
+
+    /**
+     * Open a pipe for reading
+     *
+     * Up to 6 pipes can be open for reading at once.  Open all the required
+     * reading pipes, and then call startListening().
+     *
+     * @see openWritingPipe
+     * @see setAddressWidth
+     *
+     * @note Pipes 0 and 1 will store a full 5-byte address. Pipes 2-5 will technically
+     * only store a single byte, borrowing up to 4 additional bytes from pipe #1 per the
+     * assigned address width.
+     * @warning Pipes 1-5 should share the same address, except the first byte.
+     * Only the first byte in the array should be unique, e.g.
+     * @code
+     *   uint8_t addresses[][6] = {"1Node","2Node"};
+     *   openReadingPipe(1,addresses[0]);
+     *   openReadingPipe(2,addresses[1]);
+     * @endcode
+     *
+     * @warning Pipe 0 is also used by the writing pipe.  So if you open
+     * pipe 0 for reading, and then startListening(), it will overwrite the
+     * writing pipe.  Ergo, do an openWritingPipe() again before write().
+     *
+     * @param number Which pipe# to open, 0-5.
+     * @param address The 24, 32 or 40 bit address of the pipe to open.
+     */
+
+    void openReadingPipe(uint8_t number, const uint8_t *address);
+
+    /**@}*/
+    /**
+     * @name Advanced Operation
+     *
+     *  Methods you can use to drive the chip in more advanced ways
+     */
+    /**@{*/
+
+    /**
+     * Print a giant block of debugging information to stdout
+     *
+     * @warning Does nothing if stdout is not defined.  See fdevopen in stdio.h
+     * The printf.h file is included with the library for Arduino.
+     * @code
+     * #include <printf.h>
+     * setup(){
+     *  Serial.begin(115200);
+     *  printf_begin();
+     *  ...
+     * }
+     * @endcode
+     */
+    void printDetails(void);
+
+    /**
+     * Test whether there are bytes available to be read in the
+     * FIFO buffers.
+     *
+     * @param[out] pipe_num Which pipe has the payload available
+     *
+     * @code
+     * uint8_t pipeNum;
+     * if(radio.available(&pipeNum)){
+     *   radio.read(&data,sizeof(data));
+     *   Serial.print("Got data on pipe");
+     *   Serial.println(pipeNum);
+     * }
+     * @endcode
+     * @return True if there is a payload available, false if none is
+     */
+    bool available(uint8_t* pipe_num);
+
+    /**
+     * Check if the radio needs to be read. Can be used to prevent data loss
+     * @return True if all three 32-byte radio buffers are full
+     */
+    bool rxFifoFull();
+
+    /**
+     * Enter low-power mode
+     *
+     * To return to normal power mode, call powerUp().
+     *
+     * @note After calling startListening(), a basic radio will consume about 13.5mA
+     * at max PA level.
+     * During active transmission, the radio will consume about 11.5mA, but this will
+     * be reduced to 26uA (.026mA) between sending.
+     * In full powerDown mode, the radio will consume approximately 900nA (.0009mA)
+     *
+     * @code
+     * radio.powerDown();
+     * avr_enter_sleep_mode(); // Custom function to sleep the device
+     * radio.powerUp();
+     * @endcode
+     */
+    void powerDown(void);
+
+    /**
+     * Leave low-power mode - required for normal radio operation after calling powerDown()
+     *
+     * To return to low power mode, call powerDown().
+     * @note This will take up to 5ms for maximum compatibility
+     */
+    void powerUp(void) ;
+
+    /**
+    * Write for single NOACK writes. Optionally disables acknowledgements/autoretries for a single write.
+    *
+    * @note enableDynamicAck() must be called to enable this feature
+    *
+    * Can be used with enableAckPayload() to request a response
+    * @see enableDynamicAck()
+    * @see setAutoAck()
+    * @see write()
+    *
+    * @param buf Pointer to the data to be sent
+    * @param len Number of bytes to be sent
+    * @param multicast Request ACK (0), NOACK (1)
+    */
+    bool write( const void* buf, uint8_t len, const bool multicast );
+
+    /**
+     * This will not block until the 3 FIFO buffers are filled with data.
+     * Once the FIFOs are full, writeFast will simply wait for success or
+     * timeout, and return 1 or 0 respectively. From a user perspective, just
+     * keep trying to send the same data. The library will keep auto retrying
+     * the current payload using the built in functionality.
+     * @warning It is important to never keep the nRF24L01 in TX mode and FIFO full for more than 4ms at a time. If the auto
+     * retransmit is enabled, the nRF24L01 is never in TX mode long enough to disobey this rule. Allow the FIFO
+     * to clear by issuing txStandBy() or ensure appropriate time between transmissions.
+     *
+     * @code
+     * Example (Partial blocking):
+     *
+     *            radio.writeFast(&buf,32);  // Writes 1 payload to the buffers
+     *            txStandBy();               // Returns 0 if failed. 1 if success. Blocks only until MAX_RT timeout or success. Data flushed on fail.
+     *
+     *            radio.writeFast(&buf,32);  // Writes 1 payload to the buffers
+     *            txStandBy(1000);           // Using extended timeouts, returns 1 if success. Retries failed payloads for 1 seconds before returning 0.
+     * @endcode
+     *
+     * @see txStandBy()
+     * @see write()
+     * @see writeBlocking()
+     *
+     * @param buf Pointer to the data to be sent
+     * @param len Number of bytes to be sent
+     * @return True if the payload was delivered successfully false if not
+     */
+    bool writeFast( const void* buf, uint8_t len );
+
+    /**
+    * WriteFast for single NOACK writes. Disables acknowledgements/autoretries for a single write.
+    *
+    * @note enableDynamicAck() must be called to enable this feature
+    * @see enableDynamicAck()
+    * @see setAutoAck()
+    *
+    * @param buf Pointer to the data to be sent
+    * @param len Number of bytes to be sent
+    * @param multicast Request ACK (0) or NOACK (1)
+    */
+    bool writeFast( const void* buf, uint8_t len, const bool multicast );
+
+    /**
+     * This function extends the auto-retry mechanism to any specified duration.
+     * It will not block until the 3 FIFO buffers are filled with data.
+     * If so the library will auto retry until a new payload is written
+     * or the user specified timeout period is reached.
+     * @warning It is important to never keep the nRF24L01 in TX mode and FIFO full for more than 4ms at a time. If the auto
+     * retransmit is enabled, the nRF24L01 is never in TX mode long enough to disobey this rule. Allow the FIFO
+     * to clear by issuing txStandBy() or ensure appropriate time between transmissions.
+     *
+     * @code
+     * Example (Full blocking):
+     *
+     *            radio.writeBlocking(&buf,32,1000); //Wait up to 1 second to write 1 payload to the buffers
+     *            txStandBy(1000);                   //Wait up to 1 second for the payload to send. Return 1 if ok, 0 if failed.
+     *                                               //Blocks only until user timeout or success. Data flushed on fail.
+     * @endcode
+     * @note If used from within an interrupt, the interrupt should be disabled until completion, and sei(); called to enable millis().
+     * @see txStandBy()
+     * @see write()
+     * @see writeFast()
+     *
+     * @param buf Pointer to the data to be sent
+     * @param len Number of bytes to be sent
+     * @param timeout User defined timeout in milliseconds.
+     * @return True if the payload was loaded into the buffer successfully false if not
+     */
+    bool writeBlocking( const void* buf, uint8_t len, uint32_t timeout );
+
+    /**
+     * This function should be called as soon as transmission is finished to
+     * drop the radio back to STANDBY-I mode. If not issued, the radio will
+     * remain in STANDBY-II mode which, per the data sheet, is not a recommended
+     * operating mode.
+     *
+     * @note When transmitting data in rapid succession, it is still recommended by
+     * the manufacturer to drop the radio out of TX or STANDBY-II mode if there is
+     * time enough between sends for the FIFOs to empty. This is not required if auto-ack
+     * is enabled.
+     *
+     * Relies on built-in auto retry functionality.
+     *
+     * @code
+     * Example (Partial blocking):
+     *
+     *            radio.writeFast(&buf,32);
+     *            radio.writeFast(&buf,32);
+     *            radio.writeFast(&buf,32);  //Fills the FIFO buffers up
+     *            bool ok = txStandBy();     //Returns 0 if failed. 1 if success.
+     *                                       //Blocks only until MAX_RT timeout or success. Data flushed on fail.
+     * @endcode
+     * @see txStandBy(unsigned long timeout)
+     * @return True if transmission is successful
+     *
+     */
+    bool txStandBy();
+
+    /**
+     * This function allows extended blocking and auto-retries per a user defined timeout
+     * @code
+     *    Fully Blocking Example:
+     *
+     *            radio.writeFast(&buf,32);
+     *            radio.writeFast(&buf,32);
+     *            radio.writeFast(&buf,32);   //Fills the FIFO buffers up
+     *            bool ok = txStandBy(1000);  //Returns 0 if failed after 1 second of retries. 1 if success.
+     *                                        //Blocks only until user defined timeout or success. Data flushed on fail.
+     * @endcode
+     * @note If used from within an interrupt, the interrupt should be disabled until completion, and sei(); called to enable millis().
+     * @param timeout Number of milliseconds to retry failed payloads
+     * @return True if transmission is successful
+     *
+     */
+    bool txStandBy(uint32_t timeout, bool startTx = 0);
+
+    /**
+     * Write an ack payload for the specified pipe
+     *
+     * The next time a message is received on @p pipe, the data in @p buf will
+     * be sent back in the acknowledgement.
+     * @see enableAckPayload()
+     * @see enableDynamicPayloads()
+     * @warning Only three of these can be pending at any time as there are only 3 FIFO buffers.<br> Dynamic payloads must be enabled.
+     * @note Ack payloads are handled automatically by the radio chip when a payload is received. Users should generally
+     * write an ack payload as soon as startListening() is called, so one is available when a regular payload is received.
+     * @note Ack payloads are dynamic payloads. This only works on pipes 0&1 by default. Call
+     * enableDynamicPayloads() to enable on all pipes.
+     *
+     * @param pipe Which pipe# (typically 1-5) will get this response.
+     * @param buf Pointer to data that is sent
+     * @param len Length of the data to send, up to 32 bytes max.  Not affected
+     * by the static payload set by setPayloadSize().
+     */
+    void writeAckPayload(uint8_t pipe, const void* buf, uint8_t len);
+
+    /**
+     * Determine if an ack payload was received in the most recent call to
+     * write(). The regular available() can also be used.
+     *
+     * Call read() to retrieve the ack payload.
+     *
+     * @return True if an ack payload is available.
+     */
+    bool isAckPayloadAvailable(void);
+
+    /**
+     * Call this when you get an interrupt to find out why
+     *
+     * Tells you what caused the interrupt, and clears the state of
+     * interrupts.
+     *
+     * @param[out] tx_ok The send was successful (TX_DS)
+     * @param[out] tx_fail The send failed, too many retries (MAX_RT)
+     * @param[out] rx_ready There is a message waiting to be read (RX_DS)
+     */
+    void whatHappened(bool& tx_ok,bool& tx_fail,bool& rx_ready);
+
+    /**
+     * Non-blocking write to the open writing pipe used for buffered writes
+     *
+     * @note Optimization: This function now leaves the CE pin high, so the radio
+     * will remain in TX or STANDBY-II Mode until a txStandBy() command is issued. Can be used as an alternative to startWrite()
+     * if writing multiple payloads at once.
+     * @warning It is important to never keep the nRF24L01 in TX mode with FIFO full for more than 4ms at a time. If the auto
+     * retransmit/autoAck is enabled, the nRF24L01 is never in TX mode long enough to disobey this rule. Allow the FIFO
+     * to clear by issuing txStandBy() or ensure appropriate time between transmissions.
+     *
+     * @see write()
+     * @see writeFast()
+     * @see startWrite()
+     * @see writeBlocking()
+     *
+     * For single noAck writes see:
+     * @see enableDynamicAck()
+     * @see setAutoAck()
+     *
+     * @param buf Pointer to the data to be sent
+     * @param len Number of bytes to be sent
+     * @param multicast Request ACK (0) or NOACK (1)
+     * @return True if the payload was delivered successfully false if not
+     */
+    void startFastWrite( const void* buf, uint8_t len, const bool multicast, bool startTx = 1 );
+
+    /**
+     * Non-blocking write to the open writing pipe
+     *
+     * Just like write(), but it returns immediately. To find out what happened
+     * to the send, catch the IRQ and then call whatHappened().
+     *
+     * @see write()
+     * @see writeFast()
+     * @see startFastWrite()
+     * @see whatHappened()
+     *
+     * For single noAck writes see:
+     * @see enableDynamicAck()
+     * @see setAutoAck()
+     *
+     * @param buf Pointer to the data to be sent
+     * @param len Number of bytes to be sent
+     * @param multicast Request ACK (0) or NOACK (1)
+     *
+     */
+    void startWrite( const void* buf, uint8_t len, const bool multicast );
+
+    /**
+     * This function is mainly used internally to take advantage of the auto payload
+     * re-use functionality of the chip, but can be beneficial to users as well.
+     *
+     * The function will instruct the radio to re-use the data in the FIFO buffers,
+     * and instructs the radio to re-send once the timeout limit has been reached.
+     * Used by writeFast and writeBlocking to initiate retries when a TX failure
+     * occurs. Retries are automatically initiated except with the standard write().
+     * This way, data is not flushed from the buffer until switching between modes.
+     *
+     * @note This is to be used AFTER auto-retry fails if wanting to resend
+     * using the built-in payload reuse features.
+     * After issuing reUseTX(), it will keep reending the same payload forever or until
+     * a payload is written to the FIFO, or a flush_tx command is given.
+     */
+    void reUseTX();
+
+    /**
+     * Empty the transmit buffer. This is generally not required in standard operation.
+     * May be required in specific cases after stopListening() , if operating at 250KBPS data rate.
+     *
+     * @return Current value of status register
+     */
+    uint8_t flush_tx(void);
+
+    /**
+     * Test whether there was a carrier on the line for the
+     * previous listening period.
+     *
+     * Useful to check for interference on the current channel.
+     *
+     * @return true if was carrier, false if not
+     */
+    bool testCarrier(void);
+
+    /**
+     * Test whether a signal (carrier or otherwise) greater than
+     * or equal to -64dBm is present on the channel. Valid only
+     * on nRF24L01P (+) hardware. On nRF24L01, use testCarrier().
+     *
+     * Useful to check for interference on the current channel and
+     * channel hopping strategies.
+     *
+     * @code
+     * bool goodSignal = radio.testRPD();
+     * if(radio.available()){
+     *    Serial.println(goodSignal ? "Strong signal > 64dBm" : "Weak signal < 64dBm" );
+     *    radio.read(0,0);
+     * }
+     * @endcode
+     * @return true if signal => -64dBm, false if not
+     */
+    bool testRPD(void) ;
+
+    /**
+     * Test whether this is a real radio, or a mock shim for
+     * debugging.  Setting either pin to 0xff is the way to
+     * indicate that this is not a real radio.
+     *
+     * @return true if this is a legitimate radio
+     */
+    bool isValid() {
+        return ce_pin != 0xff && csn_pin != 0xff;
+    }
+
+    /**
+    * Close a pipe after it has been previously opened.
+    * Can be safely called without having previously opened a pipe.
+    * @param pipe Which pipe # to close, 0-5.
+    */
+    void closeReadingPipe( uint8_t pipe ) ;
+
+    /**
+    * Enable error detection by un-commenting #define FAILURE_HANDLING in RF24_config.h
+    * If a failure has been detected, it usually indicates a hardware issue. By default the library
+    * will cease operation when a failure is detected.
+    * This should allow advanced users to detect and resolve intermittent hardware issues.
+    *
+    * In most cases, the radio must be re-enabled via radio.begin(); and the appropriate settings
+    * applied after a failure occurs, if wanting to re-enable the device immediately.
+    *
+    * Usage: (Failure handling must be enabled per above)
+    *  @code
+    *  if(radio.failureDetected){
+    *    radio.begin();                       // Attempt to re-configure the radio with defaults
+    *    radio.failureDetected = 0;           // Reset the detection value
+    *    radio.openWritingPipe(addresses[1]); // Re-configure pipe addresses
+    *    radio.openReadingPipe(1,addresses[0]);
+    *    report_failure();                    // Blink leds, send a message, etc. to indicate failure
+    *  }
+    * @endcode
+    */
+    //#if defined (FAILURE_HANDLING)
+    bool failureDetected;
+    //#endif
+
+    /**@}*/
+
+    /**@}*/
+    /**
+     * @name Optional Configurators
+     *
+     *  Methods you can use to get or set the configuration of the chip.
+     *  None are required.  Calling begin() sets up a reasonable set of
+     *  defaults.
+     */
+    /**@{*/
+
+    /**
+    * Set the address width from 3 to 5 bytes (24, 32 or 40 bit)
+    *
+    * @param a_width The address width to use: 3,4 or 5
+    */
+
+    void setAddressWidth(uint8_t a_width);
+
+    /**
+     * Set the number and delay of retries upon failed submit
+     *
+     * @param delay How long to wait between each retry, in multiples of 250us,
+     * max is 15.  0 means 250us, 15 means 4000us.
+     * @param count How many retries before giving up, max 15
+     */
+    void setRetries(uint8_t delay, uint8_t count);
+
+    /**
+     * Set RF communication channel
+     *
+     * @param channel Which RF channel to communicate on, 0-125
+     */
+    void setChannel(uint8_t channel);
+
+    /**
+    * Get RF communication channel
+    *
+    * @return The currently configured RF Channel
+    */
+    uint8_t getChannel(void);
+
+    /**
+     * Set Static Payload Size
+     *
+     * This implementation uses a pre-stablished fixed payload size for all
+     * transmissions.  If this method is never called, the driver will always
+     * transmit the maximum payload size (32 bytes), no matter how much
+     * was sent to write().
+     *
+     * @todo Implement variable-sized payloads feature
+     *
+     * @param size The number of bytes in the payload
+     */
+    void setPayloadSize(uint8_t size);
+
+    /**
+     * Get Static Payload Size
+     *
+     * @see setPayloadSize()
+     *
+     * @return The number of bytes in the payload
+     */
+    uint8_t getPayloadSize(void);
+
+    /**
+     * Get Dynamic Payload Size
+     *
+     * For dynamic payloads, this pulls the size of the payload off
+     * the chip
+     *
+     * @note Corrupt packets are now detected and flushed per the
+     * manufacturer.
+     * @code
+     * if(radio.available()){
+     *   if(radio.getDynamicPayloadSize() < 1){
+     *     // Corrupt payload has been flushed
+     *     return;
+     *   }
+     *   radio.read(&data,sizeof(data));
+     * }
+     * @endcode
+     *
+     * @return Payload length of last-received dynamic payload
+     */
+    uint8_t getDynamicPayloadSize(void);
+
+    /**
+     * Enable custom payloads on the acknowledge packets
+     *
+     * Ack payloads are a handy way to return data back to senders without
+     * manually changing the radio modes on both units.
+     *
+     * @note Ack payloads are dynamic payloads. This only works on pipes 0&1 by default. Call
+     * enableDynamicPayloads() to enable on all pipes.
+     */
+    void enableAckPayload(void);
+
+    /**
+     * Enable dynamically-sized payloads
+     *
+     * This way you don't always have to send large packets just to send them
+     * once in a while.  This enables dynamic payloads on ALL pipes.
+     *
+     */
+    void enableDynamicPayloads(void);
+
+    /**
+     * Enable dynamic ACKs (single write multicast or unicast) for chosen messages
+     *
+     * @note To enable full multicast or per-pipe multicast, use setAutoAck()
+     *
+     * @warning This MUST be called prior to attempting single write NOACK calls
+     * @code
+     * radio.enableDynamicAck();
+     * radio.write(&data,32,1);  // Sends a payload with no acknowledgement requested
+     * radio.write(&data,32,0);  // Sends a payload using auto-retry/autoACK
+     * @endcode
+     */
+    void enableDynamicAck();
+
+    /**
+     * Determine whether the hardware is an nRF24L01+ or not.
+     *
+     * @return true if the hardware is nRF24L01+ (or compatible) and false
+     * if its not.
+     */
+    bool isPVariant(void) ;
+
+    /**
+     * Enable or disable auto-acknowlede packets
+     *
+     * This is enabled by default, so it's only needed if you want to turn
+     * it off for some reason.
+     *
+     * @param enable Whether to enable (true) or disable (false) auto-acks
+     */
+    void setAutoAck(bool enable);
+
+    /**
+     * Enable or disable auto-acknowlede packets on a per pipeline basis.
+     *
+     * AA is enabled by default, so it's only needed if you want to turn
+     * it off/on for some reason on a per pipeline basis.
+     *
+     * @param pipe Which pipeline to modify
+     * @param enable Whether to enable (true) or disable (false) auto-acks
+     */
+    void setAutoAck( uint8_t pipe, bool enable ) ;
+
+    /**
+     * Set Power Amplifier (PA) level to one of four levels:
+     * RF24_PA_MIN, RF24_PA_LOW, RF24_PA_HIGH and RF24_PA_MAX
+     *
+     * The power levels correspond to the following output levels respectively:
+     * NRF24L01: -18dBm, -12dBm,-6dBM, and 0dBm
+     *
+     * SI24R1: -6dBm, 0dBm, 3dBM, and 7dBm.
+     *
+     * @param level Desired PA level.
+     */
+    void setPALevel ( uint8_t level );
+
+    /**
+     * Fetches the current PA level.
+     *
+     * NRF24L01: -18dBm, -12dBm, -6dBm and 0dBm
+     * SI24R1:   -6dBm, 0dBm, 3dBm, 7dBm
+     *
+     * @return Returns values 0 to 3 representing the PA Level.
+     */
+    uint8_t getPALevel( void );
+
+    /**
+     * Set the transmission data rate
+     *
+     * @warning setting RF24_250KBPS will fail for non-plus units
+     *
+     * @param speed RF24_250KBPS for 250kbs, RF24_1MBPS for 1Mbps, or RF24_2MBPS for 2Mbps
+     * @return true if the change was successful
+     */
+    bool setDataRate(rf24_datarate_e speed);
+
+    /**
+     * Fetches the transmission data rate
+     *
+     * @return Returns the hardware's currently configured datarate. The value
+     * is one of 250kbs, RF24_1MBPS for 1Mbps, or RF24_2MBPS, as defined in the
+     * rf24_datarate_e enum.
+     */
+    rf24_datarate_e getDataRate( void ) ;
+
+    /**
+     * Set the CRC length
+     * <br>CRC checking cannot be disabled if auto-ack is enabled
+     * @param length RF24_CRC_8 for 8-bit or RF24_CRC_16 for 16-bit
+     */
+    void setCRCLength(rf24_crclength_e length);
+
+    /**
+     * Get the CRC length
+     * <br>CRC checking cannot be disabled if auto-ack is enabled
+     * @return RF24_DISABLED if disabled or RF24_CRC_8 for 8-bit or RF24_CRC_16 for 16-bit
+     */
+    rf24_crclength_e getCRCLength(void);
+
+    /**
+     * Disable CRC validation
+     *
+     * @warning CRC cannot be disabled if auto-ack/ESB is enabled.
+     */
+    void disableCRC( void ) ;
+
+    /**
+    * The radio will generate interrupt signals when a transmission is complete,
+    * a transmission fails, or a payload is received. This allows users to mask
+    * those interrupts to prevent them from generating a signal on the interrupt
+    * pin. Interrupts are enabled on the radio chip by default.
+    *
+    * @code
+    *     Mask all interrupts except the receive interrupt:
+    *
+    *     radio.maskIRQ(1,1,0);
+    * @endcode
+    *
+    * @param tx_ok  Mask transmission complete interrupts
+    * @param tx_fail  Mask transmit failure interrupts
+    * @param rx_ready Mask payload received interrupts
+    */
+    void maskIRQ(bool tx_ok,bool tx_fail,bool rx_ready);
+
+    /**@}*/
+    /**
+     * @name Deprecated
+     *
+     *  Methods provided for backwards compabibility.
+     */
+    /**@{*/
+
+
+    /**
+     * Open a pipe for reading
+     * @note For compatibility with old code only, see new function
+     *
+     * @warning Pipes 1-5 should share the first 32 bits.
+     * Only the least significant byte should be unique, e.g.
+     * @code
+     *   openReadingPipe(1,0xF0F0F0F0AA);
+     *   openReadingPipe(2,0xF0F0F0F066);
+     * @endcode
+     *
+     * @warning Pipe 0 is also used by the writing pipe.  So if you open
+     * pipe 0 for reading, and then startListening(), it will overwrite the
+     * writing pipe.  Ergo, do an openWritingPipe() again before write().
+     *
+     * @param number Which pipe# to open, 0-5.
+     * @param address The 40-bit address of the pipe to open.
+     */
+    void openReadingPipe(uint8_t number, uint64_t address);
+
+    /**
+     * Open a pipe for writing
+     * @note For compatibility with old code only, see new function
+     *
+     * Addresses are 40-bit hex values, e.g.:
+     *
+     * @code
+     *   openWritingPipe(0xF0F0F0F0F0);
+     * @endcode
+     *
+     * @param address The 40-bit address of the pipe to open.
+     */
+    void openWritingPipe(uint64_t address);
+
+private:
+
+    /**
+     * @name Low-level internal interface.
+     *
+     *  Protected methods that address the chip directly.  Regular users cannot
+     *  ever call these.  They are documented for completeness and for developers who
+     *  may want to extend this class.
+     */
+    /**@{*/
+
+    /**
+     * Set chip select pin
+     *
+     * Running SPI bus at PI_CLOCK_DIV2 so we don't waste time transferring data
+     * and best of all, we make use of the radio's FIFO buffers. A lower speed
+     * means we're less likely to effectively leverage our FIFOs and pay a higher
+     * AVR runtime cost as toll.
+     *
+     * @param mode HIGH to take this unit off the SPI bus, LOW to put it on
+     */
+    void csn(bool mode);
+
+    /**
+     * Set chip enable
+     *
+     * @param level HIGH to actively begin transmission or LOW to put in standby.  Please see data sheet
+     * for a much more detailed description of this pin.
+     */
+    void ce(bool level);
+
+    /**
+     * Read a chunk of data in from a register
+     *
+     * @param reg Which register. Use constants from nRF24L01.h
+     * @param buf Where to put the data
+     * @param len How many bytes of data to transfer
+     * @return Current value of status register
+     */
+    uint8_t read_register(uint8_t reg, uint8_t* buf, uint8_t len);
+
+    /**
+     * Read single byte from a register
+     *
+     * @param reg Which register. Use constants from nRF24L01.h
+     * @return Current value of register @p reg
+     */
+    uint8_t read_register(uint8_t reg);
+
+    /**
+     * Write a chunk of data to a register
+     *
+     * @param reg Which register. Use constants from nRF24L01.h
+     * @param buf Where to get the data
+     * @param len How many bytes of data to transfer
+     * @return Current value of status register
+     */
+    uint8_t write_register(uint8_t reg, const uint8_t* buf, uint8_t len);
+
+    /**
+     * Write a single byte to a register
+     *
+     * @param reg Which register. Use constants from nRF24L01.h
+     * @param value The new value to write
+     * @return Current value of status register
+     */
+    uint8_t write_register(uint8_t reg, uint8_t value);
+
+    /**
+     * Write the transmit payload
+     *
+     * The size of data written is the fixed payload size, see getPayloadSize()
+     *
+     * @param buf Where to get the data
+     * @param len Number of bytes to be sent
+     * @return Current value of status register
+     */
+    uint8_t write_payload(const void* buf, uint8_t len, const uint8_t writeType);
+
+    /**
+     * Read the receive payload
+     *
+     * The size of data read is the fixed payload size, see getPayloadSize()
+     *
+     * @param buf Where to put the data
+     * @param len Maximum number of bytes to read
+     * @return Current value of status register
+     */
+    uint8_t read_payload(void* buf, uint8_t len);
+
+    /**
+     * Empty the receive buffer
+     *
+     * @return Current value of status register
+     */
+    uint8_t flush_rx(void);
+
+    /**
+     * Retrieve the current status of the chip
+     *
+     * @return Current value of status register
+     */
+    uint8_t get_status(void);
+
+#if !defined (MINIMAL)
+    /**
+     * Decode and print the given status to stdout
+     *
+     * @param status Status value to print
+     *
+     * @warning Does nothing if stdout is not defined.  See fdevopen in stdio.h
+     */
+    void print_status(uint8_t status);
+
+    /**
+     * Decode and print the given 'observe_tx' value to stdout
+     *
+     * @param value The observe_tx value to print
+     *
+     * @warning Does nothing if stdout is not defined.  See fdevopen in stdio.h
+     */
+    void print_observe_tx(uint8_t value);
+
+    /**
+     * Print the name and value of an 8-bit register to stdout
+     *
+     * Optionally it can print some quantity of successive
+     * registers on the same line.  This is useful for printing a group
+     * of related registers on one line.
+     *
+     * @param name Name of the register
+     * @param reg Which register. Use constants from nRF24L01.h
+     * @param qty How many successive registers to print
+     */
+    void print_byte_register(const char* name, uint8_t reg, uint8_t qty = 1);
+
+    /**
+     * Print the name and value of a 40-bit address register to stdout
+     *
+     * Optionally it can print some quantity of successive
+     * registers on the same line.  This is useful for printing a group
+     * of related registers on one line.
+     *
+     * @param name Name of the register
+     * @param reg Which register. Use constants from nRF24L01.h
+     * @param qty How many successive registers to print
+     */
+    void print_address_register(const char* name, uint8_t reg, uint8_t qty = 1);
+#endif
+    /**
+     * Turn on or off the special features of the chip
+     *
+     * The chip has certain 'features' which are only available when the 'features'
+     * are enabled.  See the datasheet for details.
+     */
+    void toggle_features(void);
+
+    /**
+     * Built in spi transfer function to simplify repeating code repeating code
+     */
+
+    uint8_t spiTrans(uint8_t cmd);
+
+#if defined (FAILURE_HANDLING)
+    void errNotify(void);
+#endif
+
+    /**@}*/
+
+};
+
+
+#endif // __RF24_H__
+