refactor: break out different areas of functionality

watch-library/watch/watch_extint.h

@@ -0,0 +1,52 @@
+/*
+ * MIT License
+ *
+ * Copyright (c) 2020 Joey Castillo
+ *
+ * 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 watch_extint.h
+
+#include "hal_ext_irq.h"
+
+/** @addtogroup buttons Buttons
+  * @brief This section covers functions related to the three buttons: Light, Mode and Alarm.
+  * @details The buttons are the core input UI of the watch, and the way the user will interact with
+  *          your application. They are active high, pulled down by the microcontroller, and triggered
+  *          when one of the "pushers" brings a tab from the metal frame into contact with the edge
+  *          of the board. Note that the buttons can only wake the watch from STANDBY mode (except maybe for the
+  *          ALARM button; still working on that one). The external interrupt controller runs in
+             STANDBY mode, but it does not runin BACKUP mode; to wake from BACKUP, buttons will not cut it,
+  */
+/// @{
+/** @brief Enables the external interrupt controller for use with the buttons.
+  * @note The BTN_ALARM button runs off of an interrupt in the the RTC controller, not the EIC. If your
+  *       application ONLY makes use of the alarm button, you do not need to call this method; you can
+  *       save ~5µA by leaving the EIC disabled and only registering a callback for BTN_ALARM.
+  */
+void watch_enable_buttons();
+
+/** @brief Configures an external interrupt on one of the button pins.
+  * @param pin One of pins BTN_LIGHT, BTN_MODE or BTN_ALARM.
+  * @param callback The function you wish to have called when the button is pressed.
+  * @note The BTN_ALARM button runs off of an interrupt in the the RTC controller, not the EIC. This
+  *       implementation detail should not make any difference to your app,
+  */
+void watch_register_button_callback(const uint8_t pin, ext_irq_cb_t callback);
+/// @}