Point Labs / STM_Watchdog

Class implementation for the STM32 watchdog timer.

Watchdog.h@0:2d9d71938413, 2019-10-03 (annotated)

Committer:
rlanders73
Date:
Thu Oct 03 18:04:23 2019 +0000
Revision:
0:2d9d71938413
This is a class implementation for the STM32 watchdog timer.

Who changed what in which revision?

UserRevisionLine numberNew contents of line
rlanders73 0:2d9d71938413 1 /// @file Watchdog.h provides the interface to the Watchdog module
rlanders73 0:2d9d71938413 2 ///
rlanders73 0:2d9d71938413 3 /// This provides basic Watchdog service for the mbed. You can configure
rlanders73 0:2d9d71938413 4 /// various timeout intervals that meet your system needs. Additionally,
rlanders73 0:2d9d71938413 5 /// it is possible to identify if the Watchdog was the cause of any
rlanders73 0:2d9d71938413 6 /// system restart, permitting the application code to take appropriate
rlanders73 0:2d9d71938413 7 /// behavior.
rlanders73 0:2d9d71938413 8 ///
rlanders73 0:2d9d71938413 9 /// Adapted from Simon's Watchdog code from http://mbed.org/forum/mbed/topic/508/
rlanders73 0:2d9d71938413 10 ///
rlanders73 0:2d9d71938413 11 /// @note Copyright © 2011 by Smartware Computing, all rights reserved.
rlanders73 0:2d9d71938413 12 /// This software may be used to derive new software, as long as
rlanders73 0:2d9d71938413 13 /// this copyright statement remains in the source file.
rlanders73 0:2d9d71938413 14 /// @author David Smart
rlanders73 0:2d9d71938413 15 ///
rlanders73 0:2d9d71938413 16 /// History
rlanders73 0:2d9d71938413 17 /// \li v1.00 - 20110616: initial release with some documentation improvements
rlanders73 0:2d9d71938413 18 ///
rlanders73 0:2d9d71938413 19 #ifndef WATCHDOG_H
rlanders73 0:2d9d71938413 20 #define WATCHDOG_H
rlanders73 0:2d9d71938413 21 #include "mbed.h"
rlanders73 0:2d9d71938413 22
rlanders73 0:2d9d71938413 23 /// The Watchdog class provides the interface to the Watchdog feature
rlanders73 0:2d9d71938413 24 ///
rlanders73 0:2d9d71938413 25 /// Embedded programs, by their nature, are usually unattended. If things
rlanders73 0:2d9d71938413 26 /// go wrong, it is usually important that the system attempts to recover.
rlanders73 0:2d9d71938413 27 /// Aside from robust software, a hardware watchdog can monitor the
rlanders73 0:2d9d71938413 28 /// system and initiate a system reset when appropriate.
rlanders73 0:2d9d71938413 29 ///
rlanders73 0:2d9d71938413 30 /// This Watchdog is patterned after one found elsewhere on the mbed site,
rlanders73 0:2d9d71938413 31 /// however this one also provides a method for the application software
rlanders73 0:2d9d71938413 32 /// to determine the cause of the reset - watchdog or otherwise.
rlanders73 0:2d9d71938413 33 ///
rlanders73 0:2d9d71938413 34 /// example:
rlanders73 0:2d9d71938413 35 /// @code
rlanders73 0:2d9d71938413 36 /// Watchdog wd;
rlanders73 0:2d9d71938413 37 ///
rlanders73 0:2d9d71938413 38 /// ...
rlanders73 0:2d9d71938413 39 /// main() {
rlanders73 0:2d9d71938413 40 /// if (wd.WatchdogCausedReset())
rlanders73 0:2d9d71938413 41 /// pc.printf("Watchdog caused reset.\r\n");
rlanders73 0:2d9d71938413 42 ///
rlanders73 0:2d9d71938413 43 /// wd.Configure(3.0); // sets the timeout interval
rlanders73 0:2d9d71938413 44 /// for (;;) {
rlanders73 0:2d9d71938413 45 /// wd.Service(); // kick the dog before the timeout
rlanders73 0:2d9d71938413 46 /// // do other work
rlanders73 0:2d9d71938413 47 /// }
rlanders73 0:2d9d71938413 48 /// }
rlanders73 0:2d9d71938413 49 /// @endcode
rlanders73 0:2d9d71938413 50 ///
rlanders73 0:2d9d71938413 51 class Watchdog {
rlanders73 0:2d9d71938413 52 public:
rlanders73 0:2d9d71938413 53 /// Create a Watchdog object
rlanders73 0:2d9d71938413 54 ///
rlanders73 0:2d9d71938413 55 /// example:
rlanders73 0:2d9d71938413 56 /// @code
rlanders73 0:2d9d71938413 57 /// Watchdog wd; // placed before main
rlanders73 0:2d9d71938413 58 /// @endcode
rlanders73 0:2d9d71938413 59 Watchdog();
rlanders73 0:2d9d71938413 60
rlanders73 0:2d9d71938413 61 /// Configure the timeout for the Watchdog
rlanders73 0:2d9d71938413 62 ///
rlanders73 0:2d9d71938413 63 /// This configures the Watchdog service and starts it. It must
rlanders73 0:2d9d71938413 64 /// be serviced before the timeout, or the system will be restarted.
rlanders73 0:2d9d71938413 65 ///
rlanders73 0:2d9d71938413 66 /// example:
rlanders73 0:2d9d71938413 67 /// @code
rlanders73 0:2d9d71938413 68 /// ...
rlanders73 0:2d9d71938413 69 /// wd.Configure(1.4); // configure for a 1.4 second timeout
rlanders73 0:2d9d71938413 70 /// ...
rlanders73 0:2d9d71938413 71 /// @endcode
rlanders73 0:2d9d71938413 72 ///
rlanders73 0:2d9d71938413 73 /// @param[in] timeout in seconds, as a floating point number
rlanders73 0:2d9d71938413 74 /// @returns none
rlanders73 0:2d9d71938413 75 ///
rlanders73 0:2d9d71938413 76 void Configure(float timeout);
rlanders73 0:2d9d71938413 77
rlanders73 0:2d9d71938413 78 /// Service the Watchdog so it does not cause a system reset
rlanders73 0:2d9d71938413 79 ///
rlanders73 0:2d9d71938413 80 /// example:
rlanders73 0:2d9d71938413 81 /// @code
rlanders73 0:2d9d71938413 82 /// wd.Pet();
rlanders73 0:2d9d71938413 83 /// @endcode
rlanders73 0:2d9d71938413 84 /// @returns none
rlanders73 0:2d9d71938413 85 void Pet();
rlanders73 0:2d9d71938413 86
rlanders73 0:2d9d71938413 87 /// WatchdogCausedReset identifies if the cause of the system
rlanders73 0:2d9d71938413 88 /// reset was the Watchdog
rlanders73 0:2d9d71938413 89 ///
rlanders73 0:2d9d71938413 90 /// example:
rlanders73 0:2d9d71938413 91 /// @code
rlanders73 0:2d9d71938413 92 /// if (wd.WatchdogCausedReset())) {
rlanders73 0:2d9d71938413 93 /// @endcode
rlanders73 0:2d9d71938413 94 ///
rlanders73 0:2d9d71938413 95 /// @returns true if the Watchdog was the cause of the reset
rlanders73 0:2d9d71938413 96 bool WatchdogCausedReset();
rlanders73 0:2d9d71938413 97 private:
rlanders73 0:2d9d71938413 98 bool wdreset;
rlanders73 0:2d9d71938413 99 };
rlanders73 0:2d9d71938413 100
rlanders73 0:2d9d71938413 101 #endif // WATCHDOG_H