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+/******************************************************************************
+ * The MIT License
+ *
+ * Copyright (c) 2010 Michael Hope.
+ *
+ * Permission is hereby granted, free of charge, to any person
+ * obtaining a copy of this software and associated documentation
+ * files (the "Software"), to deal in the Software without
+ * restriction, including without limitation the rights to use, copy,
+ * modify, merge, publish, distribute, sublicense, and/or sell copies
+ * of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ *****************************************************************************/
+
+/**
+ * @file libmaple/iwdg.c
+ * @brief Independent watchdog (IWDG) support
+ */
+
+#include <libmaple/iwdg.h>
+
+/**
+ * @brief Initialise and start the watchdog
+ *
+ * The prescaler and reload set the timeout. For example, a prescaler
+ * of IWDG_PRE_32 divides the 40 kHz clock by 32 and gives roughly 1
+ * ms per reload.
+ *
+ * @param prescaler Prescaler for the 40 kHz IWDG clock.
+ * @param reload Independent watchdog counter reload value.
+ */
+void iwdg_init(iwdg_prescaler prescaler, uint16 reload) {
+ IWDG_BASE->KR = IWDG_KR_UNLOCK;
+ IWDG_BASE->PR = prescaler;
+ IWDG_BASE->RLR = reload;
+
+ /* Start things off */
+ IWDG_BASE->KR = IWDG_KR_START;
+ iwdg_feed();
+}
+
+/**
+ * @brief Reset the IWDG counter.
+ *
+ * Calling this function will cause the IWDG counter to be reset to
+ * its reload value.
+ */
+void iwdg_feed(void) {
+ IWDG_BASE->KR = IWDG_KR_FEED;
+}