rf24-pio/RF24.h

734 lines
22 KiB
C++

/*
Copyright (C) 2011 James Coliz, Jr. <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.
*/
#ifndef __RF24_H__
#define __RF24_H__
#include <RF24_config.h>
typedef enum { RF24_PA_MIN = 0,RF24_PA_LOW, RF24_PA_HIGH, RF24_PA_MAX, RF24_PA_ERROR } rf24_pa_dbm_e ;
typedef enum { RF24_1MBPS = 0, RF24_2MBPS, RF24_250KBPS } rf24_datarate_e;
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:
uint8_t ce_pin; /**< "Chip Enable" pin, activates the RX or TX role */
uint8_t csn_pin; /**< SPI Chip select */
bool wide_band; /* 2Mbs data rate in use? */
bool p_variant; /* False for RF24L01 and true for RF24L01P */
uint8_t payload_size; /**< Fixed size of payloads */
bool ack_payload_available; /**< Whether there is an ack payload waiting */
bool dynamic_payloads_enabled; /**< Whether dynamic payloads are enabled. */
uint8_t ack_payload_length; /**< Dynamic size of pending ack payload. */
uint64_t pipe0_reading_address; /**< Last address set on pipe 0 for reading. */
protected:
/**
* @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(int 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(int 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);
/**
* 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);
/**
* Empty the transmit buffer
*
* @return Current value of status register
*/
uint8_t flush_tx(void);
/**
* Retrieve the current status of the chip
*
* @return Current value of status register
*/
uint8_t get_status(void);
/**
* 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(prog_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(prog_char* name, uint8_t reg, uint8_t qty = 1);
/**
* 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);
/**@}*/
public:
/**
* @name Primary public interface
*
* These are the main methods you need to operate the chip
*/
/**@{*/
/**
* 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(uint8_t _cepin, uint8_t _cspin);
/**
* Begin operation of the chip
*
* Call this in setup(), before calling any other methods.
*/
void begin(void);
/**
* Start listening on the pipes opened for reading.
*
* Be sure to call openReadingPipe() first. Do not call write() while
* in this mode, without first calling stopListening(). Call
* isAvailable() to check for incoming traffic, and read() to get it.
*/
void startListening(void);
/**
* Stop listening for incoming messages
*
* Do this before calling write().
*/
void stopListening(void);
/**
* Write to the open writing pipe
*
* 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 60ms.
*
* 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.
*
* @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 write( const void* buf, uint8_t len );
/**
* Test whether there are bytes available to be read
*
* @return True if there is a payload available, false if none is
*/
bool available(void);
/**
* Read the payload
*
* Return the last payload received
*
* 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.
*
* @param buf Pointer to a buffer where the data should be written
* @param len Maximum number of bytes to read into the buffer
* @return True if the payload was delivered successfully false if not
*/
bool read( void* buf, uint8_t len );
/**
* Open a pipe for writing
*
* Only one pipe can be open at once, but you can change the pipe
* you'll listen to. Do not call this while actively listening.
* Remember to stopListening() first.
*
* Addresses are 40-bit hex values, e.g.:
*
* @code
* openWritingPipe(0xF0F0F0F0F0);
* @endcode
*
* @param address The 40-bit address of the pipe to open. This can be
* any value whatsoever, as long as you are the only one writing to it
* and only one other radio is listening to it. Coordinate these pipe
* addresses amongst nodes on the network.
*/
void openWritingPipe(uint64_t address);
/**
* Open a pipe for reading
*
* Up to 6 pipes can be open for reading at once. Open all the
* reading pipes, and then call startListening().
*
* @see openWritingPipe
*
* @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().
*
* @todo Enforce the restriction that pipes 1-5 must share the top 32 bits
*
* @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);
/**@}*/
/**
* @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 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, 0-127
*/
void setChannel(uint8_t channel);
/**
* 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
*
* @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.
*
* @see examples/pingpair_pl/pingpair_pl.pde
*/
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.
*
* @see examples/pingpair_pl/pingpair_dyn.pde
*/
void enableDynamicPayloads(void);
/**
* 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.
* Relative mnemonics have been used to allow for future PA level
* changes. According to 6.5 of the nRF24L01+ specification sheet,
* they translate to: RF24_PA_MIN=-18dBm, RF24_PA_LOW=-12dBm,
* RF24_PA_MED=-6dBM, and RF24_PA_HIGH=0dBm.
*
* @param level Desired PA level.
*/
void setPALevel( rf24_pa_dbm_e level ) ;
/**
* Fetches the current PA level.
*
* @return Returns a value from the rf24_pa_dbm_e enum describing
* the current PA setting. Please remember, all values represented
* by the enum mnemonics are negative dBm. See setPALevel for
* return value descriptions.
*/
rf24_pa_dbm_e 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
*
* @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
*
* @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
*
*/
void disableCRC( void ) ;
/**@}*/
/**
* @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
*/
void printDetails(void);
/**
* Enter low-power mode
*
* To return to normal power mode, either write() some data or
* startListening, or powerUp().
*/
void powerDown(void);
/**
* Leave low-power mode - making radio more responsive
*
* To return to low power mode, call powerDown().
*/
void powerUp(void) ;
/**
* Test whether there are bytes available to be read
*
* Use this version to discover on which pipe the message
* arrived.
*
* @param[out] pipe_num Which pipe has the payload available
* @return True if there is a payload available, false if none is
*/
bool available(uint8_t* pipe_num);
/**
* 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 whatHappened()
*
* @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
*/
void startWrite( const void* buf, uint8_t len );
/**
* 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.
*
* @warning According to the data sheet, only three of these can be pending
* at any time. I have not tested this.
*
* @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().
*
* Call read() to retrieve the ack payload.
*
* @warning Calling this function clears the internal flag which indicates
* a payload is available. If it returns true, you must read the packet
* out as the very next interaction with the radio, or the results are
* undefined.
*
* @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);
/**
* 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.
*
* @return true if signal => -64dBm, false if not
*/
bool testRPD(void) ;
/**@}*/
};
/**
* @example GettingStarted.pde
*
* This is an example which corresponds to my "Getting Started" blog post
* for Getting Started with nRF24L01+ radios.
*
* It is an example of how to use the RF24 class. Write this sketch to two
* different nodes. Put one of the nodes into 'transmit' mode by connecting
* with the serial monitor and sending a 'T'. The ping node sends the current
* time to the pong node, which responds by sending the value back. The ping
* node can then see how long the whole cycle took.
*/
/**
* @example led_remote.pde
*
* This is an example of how to use the RF24 class to control a remote
* bank of LED's using buttons on a remote control.
*
* Every time the buttons change on the remote, the entire state of
* buttons is send to the led board, which displays the state.
*/
/**
* @example pingpair.pde
*
* This is an example of how to use the RF24 class. Write this sketch to two
* different nodes, connect the role_pin to ground on one. The ping node sends
* the current time to the pong node, which responds by sending the value back.
* The ping node can then see how long the whole cycle took.
*/
/**
* @example starping.pde
*
* This sketch is a more complex example of using the RF24 library for Arduino.
* Deploy this on up to six nodes. Set one as the 'pong receiver' by tying the
* role_pin low, and the others will be 'ping transmit' units. The ping units
* unit will send out the value of millis() once a second. The pong unit will
* respond back with a copy of the value. Each ping unit can get that response
* back, and determine how long the whole cycle took.
*
* This example requires a bit more complexity to determine which unit is which.
* The pong receiver is identified by having its role_pin tied to ground.
* The ping senders are further differentiated by a byte in eeprom.
*/
/**
* @example pingpair_pl.pde
*
* This is an example of how to do two-way communication without changing
* transmit/receive modes. Here, a payload is set to the transmitter within
* the Ack packet of each transmission. Note that the payload is set BEFORE
* the sender's message arrives.
*/
/**
* @example pingpair_irq.pde
*
* This is an example of how to user interrupts to interact with the radio.
* It builds on the pingpair_pl example, and uses ack payloads.
*/
/**
* @example pingpair_sleepy.pde
*
* This is an example of how to use the RF24 class to create a battery-
* efficient system. It is just like the pingpair.pde example, but the
* ping node powers down the radio and sleeps the MCU after every
* ping/pong cycle.
*/
/**
* @example scanner.pde
*
* Example to detect interference on the various channels available.
* This is a good diagnostic tool to check whether you're picking a
* good channel for your application.
*
* Inspired by cpixip.
* See http://arduino.cc/forum/index.php/topic,54795.0.html
*/
/**
* @mainpage Driver for nRF24L01(+) 2.4GHz Wireless Transceiver
*
* Design Goals: This library is designed to be...
* @li Maximally compliant with the intended operation of the chip
* @li Easy for beginners to use
* @li Consumed with a public interface that's similiar to other Arduino standard libraries
*
* NOW COMPATIBLE WITH ARDUINO 1.0 - Please use the
* <a href="https://github.com/maniacbug/RF24/tree/arduino-1.0">'arduino-1.0' branch</a>
* for use with Arduino 1.0. This will be merged into master when Arduino 1.0 is released.
*
* Please refer to:
*
* @li <a href="http://maniacbug.github.com/RF24/">Documentation Main Page</a>
* @li <a href="http://maniacbug.github.com/RF24/classRF24.html">RF24 Class Documentation</a>
* @li <a href="https://github.com/maniacbug/RF24/">Source Code</a>
* @li <a href="https://github.com/maniacbug/RF24/archives/master">Downloads Page</a>
* @li <a href="http://www.nordicsemi.com/files/Product/data_sheet/nRF24L01_Product_Specification_v2_0.pdf">Chip Datasheet</a>
*
* This chip uses the SPI bus, plus two chip control pins. Remember that pin 10 must still remain an output, or
* the SPI hardware will go into 'slave' mode.
*
* @section More More Information
*
* @subpage FAQ
*/
#endif // __RF24_H__
// vim:ai:cin:sts=2 sw=2 ft=cpp