Diff: RHGenericDriver.h

Revision:

0:ab4e012489ef

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/RHGenericDriver.h	Thu Oct 15 01:27:00 2015 +0000
@@ -0,0 +1,265 @@
+// RHGenericDriver.h
+// Author: Mike McCauley (mikem@airspayce.com)
+// Copyright (C) 2014 Mike McCauley
+// $Id: RHGenericDriver.h,v 1.16 2015/01/02 21:38:24 mikem Exp $
+
+#ifndef RHGenericDriver_h
+#define RHGenericDriver_h
+
+#include <RadioHead.h>
+
+// Defines bits of the FLAGS header reserved for use by the RadioHead library and 
+// the flags available for use by applications
+#define RH_FLAGS_RESERVED                 0xf0
+#define RH_FLAGS_APPLICATION_SPECIFIC     0x0f
+#define RH_FLAGS_NONE                     0
+
+/////////////////////////////////////////////////////////////////////
+/// \class RHGenericDriver RHGenericDriver.h <RHGenericDriver.h>
+/// \brief Abstract base class for a RadioHead driver.
+///
+/// This class defines the functions that must be provided by any RadioHead driver.
+/// Different types of driver will implement all the abstract functions, and will perhaps override 
+/// other functions in this subclass, or perhaps add new functions specifically required by that driver.
+/// Do not directly instantiate this class: it is only to be subclassed by driver classes.
+///
+/// Subclasses are expected to implement a half-duplex, unreliable, error checked, unaddressed packet transport.
+/// They are expected to carry a message payload with an appropriate maximum length for the transport hardware
+/// and to also carry unaltered 4 message headers: TO, FROM, ID, FLAGS
+///
+/// \par Headers
+///
+/// Each message sent and received by a RadioHead driver includes 4 headers:
+/// -TO The node address that the message is being sent to (broadcast RH_BROADCAST_ADDRESS (255) is permitted)
+/// -FROM The node address of the sending node
+/// -ID A message ID, distinct (over short time scales) for each message sent by a particilar node
+/// -FLAGS A bitmask of flags. The most significant 4 bits are reserved for use by RadioHead. The least
+/// significant 4 bits are reserved for applications.
+class RHGenericDriver
+{
+public:
+    /// \brief Defines different operating modes for the transport hardware
+    ///
+    /// These are the different values that can be adopted by the _mode variable and 
+    /// returned by the mode() member function,
+    typedef enum
+    {
+	RHModeInitialising = 0, ///< Transport is initialising. Initial default value until init() is called..
+	RHModeSleep,            ///< Transport hardware is in low power sleep mode (if supported)
+	RHModeIdle,             ///< Transport is idle.
+	RHModeTx,               ///< Transport is in the process of transmitting a message.
+	RHModeRx                ///< Transport is in the process of receiving a message.
+    } RHMode;
+
+    /// Constructor
+    RHGenericDriver();
+
+    /// Initialise the Driver transport hardware and software.
+    /// Make sure the Driver is properly configured before calling init().
+    /// \return true if initialisation succeeded.
+    virtual bool init();
+
+    /// Tests whether a new message is available
+    /// from the Driver. 
+    /// On most drivers, if there is an uncollected received message, and there is no message
+    /// currently bing transmitted, this will also put the Driver into RHModeRx mode until
+    /// a message is actually received by the transport, when it will be returned to RHModeIdle.
+    /// This can be called multiple times in a timeout loop.
+    /// \return true if a new, complete, error-free uncollected message is available to be retreived by recv().
+    virtual bool available() = 0;
+
+    /// Turns the receiver on if it not already on.
+    /// If there is a valid message available, copy it to buf and return true
+    /// else return false.
+    /// If a message is copied, *len is set to the length (Caution, 0 length messages are permitted).
+    /// You should be sure to call this function frequently enough to not miss any messages
+    /// It is recommended that you call it in your main loop.
+    /// \param[in] buf Location to copy the received message
+    /// \param[in,out] len Pointer to available space in buf. Set to the actual number of octets copied.
+    /// \return true if a valid message was copied to buf
+    virtual bool recv(uint8_t* buf, uint8_t* len) = 0;
+
+    /// Waits until any previous transmit packet is finished being transmitted with waitPacketSent().
+    /// Then loads a message into the transmitter and starts the transmitter. Note that a message length
+    /// of 0 is NOT permitted. If the message is too long for the underlying radio technology, send() will
+    /// return false and will not send the message.
+    /// \param[in] data Array of data to be sent
+    /// \param[in] len Number of bytes of data to send (> 0)
+    /// \return true if the message length was valid and it was correctly queued for transmit
+    virtual bool send(const uint8_t* data, uint8_t len) = 0;
+
+    /// Returns the maximum message length 
+    /// available in this Driver.
+    /// \return The maximum legal message length
+    virtual uint8_t maxMessageLength() = 0;
+
+    /// Starts the receiver and blocks until a valid received 
+    /// message is available.
+    virtual void            waitAvailable();
+
+    /// Blocks until the transmitter 
+    /// is no longer transmitting.
+    virtual bool            waitPacketSent();
+
+    /// Blocks until the transmitter is no longer transmitting.
+    /// or until the timeout occuers, whichever happens first
+    /// \param[in] timeout Maximum time to wait in milliseconds.
+    /// \return true if the RF22 completed transmission within the timeout period. False if it timed out.
+    virtual bool            waitPacketSent(uint16_t timeout);
+
+    /// Starts the receiver and blocks until a received message is available or a timeout
+    /// \param[in] timeout Maximum time to wait in milliseconds.
+    /// \return true if a message is available
+    virtual bool            waitAvailableTimeout(uint16_t timeout);
+
+    /// Sets the address of this node. Defaults to 0xFF. Subclasses or the user may want to change this.
+    /// This will be used to test the adddress in incoming messages. In non-promiscuous mode,
+    /// only messages with a TO header the same as thisAddress or the broadcast addess (0xFF) will be accepted.
+    /// In promiscuous mode, all messages will be accepted regardless of the TO header.
+    /// In a conventional multinode system, all nodes will have a unique address 
+    /// (which you could store in EEPROM).
+    /// You would normally set the header FROM address to be the same as thisAddress (though you dont have to, 
+    /// allowing the possibilty of address spoofing).
+    /// \param[in] thisAddress The address of this node.
+    virtual void setThisAddress(uint8_t thisAddress);
+
+    /// Sets the TO header to be sent in all subsequent messages
+    /// \param[in] to The new TO header value
+    virtual void           setHeaderTo(uint8_t to);
+
+    /// Sets the FROM header to be sent in all subsequent messages
+    /// \param[in] from The new FROM header value
+    virtual void           setHeaderFrom(uint8_t from);
+
+    /// Sets the ID header to be sent in all subsequent messages
+    /// \param[in] id The new ID header value
+    virtual void           setHeaderId(uint8_t id);
+
+    /// Sets and clears bits in the FLAGS header to be sent in all subsequent messages
+    /// First it clears he FLAGS according to the clear argument, then sets the flags according to the 
+    /// set argument. The default for clear always clears the application specific flags.
+    /// \param[in] set bitmask of bits to be set. Flags are cleared with the clear mask before being set.
+    /// \param[in] clear bitmask of flags to clear. Defaults to RH_FLAGS_APPLICATION_SPECIFIC
+    ///            which clears the application specific flags, resultiung in new application specific flags
+    ///            identical to the set.
+    virtual void           setHeaderFlags(uint8_t set, uint8_t clear = RH_FLAGS_APPLICATION_SPECIFIC);
+
+    /// Tells the receiver to accept messages with any TO address, not just messages
+    /// addressed to thisAddress or the broadcast address
+    /// \param[in] promiscuous true if you wish to receive messages with any TO address
+    virtual void           setPromiscuous(bool promiscuous);
+
+    /// Returns the TO header of the last received message
+    /// \return The TO header
+    virtual uint8_t        headerTo();
+
+    /// Returns the FROM header of the last received message
+    /// \return The FROM header
+    virtual uint8_t        headerFrom();
+
+    /// Returns the ID header of the last received message
+    /// \return The ID header
+    virtual uint8_t        headerId();
+
+    /// Returns the FLAGS header of the last received message
+    /// \return The FLAGS header
+    virtual uint8_t        headerFlags();
+
+    /// Returns the most recent RSSI (Receiver Signal Strength Indicator).
+    /// Usually it is the RSSI of the last received message, which is measured when the preamble is received.
+    /// If you called readRssi() more recently, it will return that more recent value.
+    /// \return The most recent RSSI measurement in dBm.
+    int8_t        lastRssi();
+
+    /// Returns the operating mode of the library.
+    /// \return the current mode, one of RF69_MODE_*
+    RHMode          mode();
+
+    /// Sets the operating mode of the transport.
+    void            setMode(RHMode mode);
+
+    /// Sets the transport hardware into low-power sleep mode
+    /// (if supported). May be overridden by specific drivers to initialte sleep mode.
+    /// If successful, the transport will stay in sleep mode until woken by 
+    /// changing mode it idle, transmit or receive (eg by calling send(), recv(), available() etc)
+    /// \return true if sleep mode is supported by transport hardware and the RadioHead driver, and if sleep mode
+    ///         was successfully entered. If sleep mode is not suported, return false.
+    virtual bool    sleep();
+
+    /// Prints a data buffer in HEX.
+    /// For diagnostic use
+    /// \param[in] prompt string to preface the print
+    /// \param[in] buf Location of the buffer to print
+    /// \param[in] len Length of the buffer in octets.
+    static void    printBuffer(const char* prompt, const uint8_t* buf, uint8_t len);
+
+    /// Returns the count of the number of bad received packets (ie packets with bad lengths, checksum etc)
+    /// which were rejected and not delivered to the application.
+    /// Caution: not all drivers can correctly report this count. Some underlying hardware only report
+    /// good packets.
+    /// \return The number of bad packets received.
+    uint16_t       rxBad();
+
+    /// Returns the count of the number of 
+    /// good received packets
+    /// \return The number of good packets received.
+    uint16_t       rxGood();
+
+    /// Returns the count of the number of 
+    /// packets successfully transmitted (though not necessarily received by the destination)
+    /// \return The number of packets successfully transmitted
+    uint16_t       txGood();
+
+protected:
+
+    /// The current transport operating mode
+    volatile RHMode     _mode;
+
+    /// This node id
+    uint8_t             _thisAddress;
+    
+    /// Whether the transport is in promiscuous mode
+    bool                _promiscuous;
+
+    /// TO header in the last received mesasge
+    volatile uint8_t    _rxHeaderTo;
+
+    /// FROM header in the last received mesasge
+    volatile uint8_t    _rxHeaderFrom;
+
+    /// ID header in the last received mesasge
+    volatile uint8_t    _rxHeaderId;
+
+    /// FLAGS header in the last received mesasge
+    volatile uint8_t    _rxHeaderFlags;
+
+    /// TO header to send in all messages
+    uint8_t             _txHeaderTo;
+
+    /// FROM header to send in all messages
+    uint8_t             _txHeaderFrom;
+
+    /// ID header to send in all messages
+    uint8_t             _txHeaderId;
+
+    /// FLAGS header to send in all messages
+    uint8_t             _txHeaderFlags;
+
+    /// The value of the last received RSSI value, in some transport specific units
+    volatile int8_t     _lastRssi;
+
+    /// Count of the number of bad messages (eg bad checksum etc) received
+    volatile uint16_t   _rxBad;
+
+    /// Count of the number of successfully transmitted messaged
+    volatile uint16_t   _rxGood;
+
+    /// Count of the number of bad messages (correct checksum etc) received
+    volatile uint16_t   _txGood;
+    
+private:
+
+};
+
+
+#endif