File content as of revision 9:84f7c088c261:

/// @file Watchdog.h provides the interface to the Watchdog module
///
/// This provides basic Watchdog service for the mbed. You can configure
/// various timeout intervals that meet your system needs. Additionally,
/// it is possible to identify if the Watchdog was the cause of any 
/// system restart, permitting the application code to take appropriate
/// behavior.
/// 
/// Adapted from Simon's Watchdog code from http://mbed.org/forum/mbed/topic/508/
///
/// @note Copyright © 2011,2015 by Smartware Computing, all rights reserved.
///     This software may be used to derive new software, as long as
///     this copyright statement remains in the source file.
/// @author David Smart
///
/// History
/// \li v2.00 - 20150315: Enhanced beyond TARGET_LPC1768 to TARGET_LPC4088, TARGET_STM
/// \li v1.00 - 20110616: initial release with some documentation improvements
///
#ifndef WATCHDOG_H
#define WATCHDOG_H
#include "mbed.h"

/// The Watchdog class provides the interface to the Watchdog feature
///
/// Embedded programs, by their nature, are usually unattended. If things
/// go wrong, it is usually important that the system attempts to recover.
/// Aside from robust software, a hardware watchdog can monitor the
/// system and initiate a system reset when appropriate.
///
/// This Watchdog is patterned after one found elsewhere on the mbed site,
/// however this one also provides a method for the application software
/// to determine the cause of the reset - watchdog or otherwise.
///
/// Supports:
/// \li TARGET_LPC1768 
/// \li TARGET_LPC4088
/// \li TARGET_STM
///
/// example:
/// @code
/// Watchdog wd;
///
/// ...
/// main() {
///    if (wd.WatchdogCausedReset())
///        pc.printf("Watchdog caused reset.\r\n");
///      
///    wd.Configure(3.0);       // sets the timeout interval
///    for (;;) {
///         wd.Service();       // kick the dog before the timeout
///         // do other work
///    }
/// }
/// @endcode
///
class Watchdog {
public:
    /// Create a Watchdog object
    ///
    /// example:
    /// @code
    /// Watchdog wd;    // placed before main
    /// @endcode
    Watchdog();
    
    /// Configure the timeout for the Watchdog
    ///
    /// This configures the Watchdog service and starts it. It must
    /// be serviced before the timeout, or the system will be restarted.
    ///
    /// example:
    /// @code
    ///     ...
    ///     wd.Configure(1.4);  // configure for a 1.4 second timeout
    ///     ...
    /// @endcode
    ///
    /// @param[in] timeout in seconds, as a floating point number
    /// @returns none
    ///
    void Configure(float timeout);
    
    /// Service the Watchdog so it does not cause a system reset
    ///
    /// example:
    /// @code
    ///    wd.Service();
    /// @endcode
    /// @returns none
    void Service();
    
    /// WatchdogCausedReset identifies if the cause of the system
    /// reset was the Watchdog
    ///
    /// example:
    /// @code
    ///    if (wd.WatchdogCausedReset())) {
    /// @endcode
    ///
    /// @returns true if the Watchdog was the cause of the reset
    bool WatchdogCausedReset();
private:
    bool wdreset;
    
    #if defined( TARGET_STM )
    /// Logarithm in base 2
    ///
    /// This function is needed for the STM32 platforms to compute the prescaler
    /// value for the watchdog timer
    ///
    /// @param[in] the input value as an unsigned integer (i.e. always positive)
    /// @returns the computed log2
    int log2(unsigned v);
    #endif
};

#endif // WATCHDOG_H