return 0;
}
-void watch_enter_deep_sleep() {
- // enable and configure the external wake interrupt, if not already set up.
- if (btn_alarm_callback == NULL && a2_callback == NULL && a4_callback == NULL) {
- gpio_set_pin_direction(BTN_ALARM, GPIO_DIRECTION_IN);
- gpio_set_pin_pull_mode(BTN_ALARM, GPIO_PULL_DOWN);
- gpio_set_pin_function(BTN_ALARM, PINMUX_PA02G_RTC_IN2);
- _extwake_register_callback(&CALENDAR_0.device, extwake_callback);
+void _watch_disable_all_pins_except_rtc() {
+ uint32_t config = RTC->MODE0.TAMPCTRL.reg;
+ uint32_t portb_pins_to_disable = 0xFFFFFFFF;
+
+ // if there's an action set on RTC/IN[0], leave PB00 configured
+ if (config & RTC_TAMPCTRL_IN0ACT_Msk) portb_pins_to_disable &= 0xFFFFFFFE;
+ // same with RTC/IN[1] and PB02
+ if (config & RTC_TAMPCTRL_IN1ACT_Msk) portb_pins_to_disable &= 0xFFFFFFFB;
+
+ // port A: always keep PA02 configured as-is; that's our ALARM button.
+ gpio_set_port_direction(0, 0xFFFFFFFB, GPIO_DIRECTION_OFF);
+ // port B: disable all pins we didn't save above.
+ gpio_set_port_direction(1, portb_pins_to_disable, GPIO_DIRECTION_OFF);
+}
+
+void _watch_disable_all_peripherals_except_slcd() {
+ _watch_disable_tcc();
+ watch_disable_adc();
+ watch_disable_external_interrupts();
+ watch_disable_i2c();
+ // TODO: replace this with a proper function when we remove the debug UART
+ SERCOM3->USART.CTRLA.reg &= ~SERCOM_USART_CTRLA_ENABLE;
+ MCLK->APBCMASK.reg &= ~MCLK_APBCMASK_SERCOM3;
+}
+
+void watch_enter_deep_sleep(char *message) {
+ // configure the ALARM interrupt (the callback doesn't matter)
+ watch_register_extwake_callback(BTN_ALARM, NULL, true);
+
+ if (message != NULL) {
+ watch_display_string(" ", 0);
+ watch_display_string(message, 0);
+ } else {
+ slcd_sync_deinit(&SEGMENT_LCD_0);
+ hri_mclk_clear_APBCMASK_SLCD_bit(SLCD);
}
- // disable SLCD
+ // disable all other peripherals
+ _watch_disable_all_peripherals_except_slcd();
+
+ // disable tick interrupt
+ watch_register_tick_callback(NULL);
+
+ // disable brownout detector interrupt, which could inadvertently wake us up.
+ SUPC->INTENCLR.bit.BOD33DET = 1;
+
+ // disable all pins
+ _watch_disable_all_pins_except_rtc();
+
+ // turn off RAM completely.
+ PM->STDBYCFG.bit.BBIASHS = 3;
+
+ // enter standby (4); we basically hang out here until an interrupt forces us to reset.
+ sleep(4);
+
+ NVIC_SystemReset();
+}
+
+void watch_enter_backup_mode() {
+ // this will not work on the current silicon revision, but I said in the documentation that we do it.
+ // so let's do it!
+ watch_register_extwake_callback(BTN_ALARM, NULL, true);
+
+ watch_register_tick_callback(NULL);
+ _watch_disable_all_peripherals_except_slcd();
slcd_sync_deinit(&SEGMENT_LCD_0);
hri_mclk_clear_APBCMASK_SLCD_bit(SLCD);
+ _watch_disable_all_pins_except_rtc();
- // TODO: disable other peripherals
-
- // go into backup sleep mode
+ // go into backup sleep mode (5). when we exit, the reset controller will take over.
sleep(5);
}
* from deep sleep (aka BACKUP) mode.
* @param pin Either pin BTN_ALARM, A2, or A4. These are the three external wake pins. If the pin
* is BTN_ALARM, this function also enables an internal pull down on that pin.
- * @param callback The callback to be called if this pin triggers outside of deep sleep mode.
+ * @param callback The callback to be called if this pin triggers outside of deep sleep mode. If
+ * this is NULL, no callback will be called even in normal mode, but the interrupt
+ * will still be enabled so that it can wake from deep sleep or backup mode.
* @param level The level you wish to scan for: true for rising, false for falling. Note that you
* cannot scan for both rising and falling edges like you can with the external interrupt
* pins; with the external wake interrupt, you can only get one or the other.
* WILL NOT be called, as the device is basically waking from reset at that point.
* @warning As of the current SAM L22 silicon revision (rev B), the BTN_ALARM pin cannot wake the
* device from BACKUP mode. You can still use this function to register a BTN_ALARM interrupt
- * in normal or STANDBY mode, but to wake from BACKUP, you will need to use pin A2 or A4.
+ * in normal or deep sleep mode, but to wake from BACKUP, you will need to use pin A2 or A4.
*/
void watch_register_extwake_callback(uint8_t pin, ext_irq_cb_t callback, bool level);
-/** @brief Stores data in one of the RTC's backup registers, which retain their data in deep sleep.
+/** @brief Unregisters the interrupt on one of the EXTWAKE pins. This will prevent a value change on
+ * one of these pins from waking the device from deep sleep or BACKUP modes.
+ * @param pin Either pin BTN_ALARM, A2, or A4. If the pin is BTN_ALARM, this function DOES NOT disable
+ * the internal pull down on that pin.
+ */
+void watch_disable_extwake_interrupt(uint8_t pin, ext_irq_cb_t callback, bool level);
+
+/** @brief Stores data in one of the RTC's backup registers, which retain their data in the deep sleep
+ and backup modes.
* @param data An unsigned 32 bit integer with the data you wish to store.
* @param reg A register from 0-7.
*/
void watch_store_backup_data(uint32_t data, uint8_t reg);
-/** @brief Gets 32 bits of data from the RTC's backup register, which retains its data in deep sleep.
+/** @brief Gets 32 bits of data from the RTC's backup register.
* @param reg A register from 0-7.
* @return An unsigned 32 bit integer with the from the backup register.
*/
uint32_t watch_get_backup_data(uint8_t reg);
+/** @brief Enters a deep sleep mode by disabling RAM retention and all peripherals except the RTC and
+ * (optionally) the LCD. You can wake from this mode by pressing the ALARM button.
+ * @param message Either NULL, or a string representing a message to display while in deep sleep mode. The
+ * message will be displayed at position 0, so you should pad out the beginning of the string
+ * with spaces if you wish for the message to appear on line 2, i.e. " SLEEP". If this
+ * parameter is NULL, the screen will be blanked, and this function will disable the SLCD
+ * peripheral for additional power savings. (also note that while the message will replace any
+ * text on the display, this function will not clear any indicators you have set. This is by
+ * design, in case you wish to leave an indicator lit in sleep mode.)
+ * @details This deep sleep mode is not the lowest power mode available (see watch_enter_backup_mode), but
+ * it has the benefit of being able to wake with a press of the ALARM button, and provides an option
+ * for displaying a message to the user when asleep. The only way to wake from this mode is by
+ * pressing the ALARM button, or receiving an interrupt on pin A2 or A4 of the nine-pin connector.
+ * (An alarm interrupt would also work, but this has not yet been implemented.) This function enables
+ * the ALARM button interrupt for you, but if you wish to wake from the A2 or A4 RTC interrupt, you
+ * must configure them by calling watch_register_extwake_callback. Note however that your callback
+ * will not be called in this case.
+ * Power consumption in deep sleep mode varies a bit with the battery voltage and the temperature,
+ * but at 3 V and ~25° C you can eoughly estimate:
+ * * ~12µA current draw with the LCD controller on (message != NULL)
+ * * ~6.5µA current draw with the LCD controller off (message == NULL)
+ * @note With RAM powered off, your application state will be cleared as soon as you call this function, and
+ * when the user wakes up the watch, your app will effectively be waking from reset. Your app's @ref
+ * app_wake_from_deep_sleep function will be called to give your app a chance to restore any state that
+ * you stored using @ref watch_store_backup_data.
+ */
+void watch_enter_deep_sleep(char *message);
+
/** @brief Enters the SAM L22's lowest-power mode, BACKUP.
* @details This function does some housekeeping before entering BACKUP mode. It first disables all
- * peripherals except for the RTC, and disables the tick interrupt (since that would wake)
- * us up from deep sleep. It also sets an external wake source on the ALARM button, if one
+ * peripherals except for the RTC, and disables the tick interrupt (since that would wake
+ * us up from deep sleep). It also sets an external wake source on the ALARM button, if one
* was not already set. If you wish to wake from another source, such as one of the external
* wake interrupt pins on the 9-pin connector, set that up prior to calling this function.
* @note If you have a callback set for an external wake interrupt, it will be called if triggered while
* in ACTIVE, IDLE or STANDBY modes, but it *will not be called* when waking from BACKUP.
* Waking from backup is effectively like waking from reset, except that your @ref
* app_wake_from_deep_sleep function will be called.
- * @warning In initial testing, it seems like the ALARM_BTN pin (PA02 RTC/IN2) cannot wake the device
- * from deep sleep mode. There is an errata note (Reference: 15010, linked) that says that
- * due to a silicon bug, PB01 cannot be used as RTC/IN2. It seems though that this bug may
- * also affect PA02. As a result — and I'm very bummed about this — you cannot use deep sleep
- * mode unless you set up an external wake interrupt using a device on the nine-pin connector
- * (i.e. an accelerometer with an interrupt pin). Otherwise your only option for waking will
- * be to unscrew the watch case and press the reset button on the back of the board.
- * http://ww1.microchip.com/downloads/en/DeviceDoc/SAM_L22_Family_Errata_DS80000782B.pdf
+ * @warning On current revisions of the SAM L22 silicon, the ALARM_BTN pin (PA02 RTC/IN2) cannot wake
+ * the device from deep sleep mode. There is an errata note (Reference: 15010) that says that
+ * due to a silicon bug, RTC/IN2 is not functional in BACKUP. As a result, you should not call
+ * this function unless you have a device on the nine-pin connector with an external interrupt
+ * on pin A2 or A4 (i.e. an accelerometer with an interrupt pin).
*/
-void watch_enter_deep_sleep();
+void watch_enter_backup_mode();
/// @}
projects / sensor-watch.git / commitdiff