Developer Configuration (Usrcfg)

This section describes the configuration methods for wake-up sources in both sleep and deep sleep modes.

Configuration Procedure

Sleep Configuration Procedure

To enable a wake-up source to bring the system out of sleep, it must be properly initialized and the corresponding wake-up event must be triggered. Please follow the steps below to configure a wake-up source for system wake-up from sleep:

• Step 1: Initialize the corresponding wake-up source and register its interrupt handler.

• Step 2: Configure the wake-up mask of the wake-up source according to Wake-up Source Configuration.

• Step 3: Check if additional clock and power status configuration is required according to Clock and Voltage Configuration.

• Step 4: Set the sleep type to either CG or PG using pmu_set_sleep_type() (default sleep type is PG).

• Step 5: Release the sleep wakelock and wait for the system to enter sleep mode.

• Step 6: During sleep, the interrupt of the wake-up source occurs, waking up the system and executing the corresponding interrupt handler.

Tip

After completing registration in Step 1, you can trigger an interrupt while the system is active to verify whether the correct interrupt handler is entered, ensuring that the wake-up source has been properly initialized.

Example code for sleep configuration can be found at sleep example.

Deep Sleep Configuration Procedure

To enable a wake-up source to bring the system out of deep sleep, follow these steps:

• Step 1: Initialize the corresponding wake-up source. No additional parameters such as wake-up masks are required.

• Step 2: Release both the sleep wakelock and deep sleep wakelock, and wait for the system to enter deep sleep mode.

• Step 3: After the system wakes up, process the wake-up event and related behaviors according to the corresponding wake-up source.

Example code for deep sleep configuration can be found at deep sleep example.

Tip

After waking up from deep sleep, the CPU is powered on again and all interrupts registered before sleep are lost. Users can obtain the wake event via SOCPS_AONWakeReason() and register the corresponding interrupt handler according to the event.

Sleep Wake-up Source Configuration

RTL8721DxRTL8720ERTL8710ERTL8726ERTL8713ERTL8730ERTL8721F

ameba_sleepcfg.c

Users can modify the above files to configure wake-up source parameters. The available configurations are shown below:

Wake-up Source Configuration

All available wake-up sources are listed in the array sleep_wevent_config[], where each entry represents a wake-up source configuration. Users can modify this array to configure whether the wake-up source can wake up the system and which CPU it wakes up.

WakeEvent_TypeDef sleep_wevent_config[] = {
   //   Module                    Wakeup
   {WAKE_SRC_AON_WAKEPIN,         WAKEUP_NULL},
   {WAKE_SRC_AON_TIM,             WAKEUP_NULL},
   {WAKE_SRC_PWR_DOWN,            WAKEUP_NULL},
   {WAKE_SRC_BOR,                 WAKEUP_NULL},
   {WAKE_SRC_ADC,                 WAKEUP_NULL},
   {WAKE_SRC_RTC,                 WAKEUP_NULL},
   {WAKE_SRC_GPIOB,               WAKEUP_NULL},
   {WAKE_SRC_GPIOA,               WAKEUP_NULL},
   {WAKE_SRC_UART_LOG,            WAKEUP_NULL},
   {WAKE_SRC_UART1,               WAKEUP_NULL},
   {WAKE_SRC_UART0,               WAKEUP_NULL},
   {WAKE_SRC_WIFI_FISR_FESR_IRQ,      WAKEUP_NULL},  /* For WiFi wakeup, do not change it*/
   ...
   {0xFFFFFFFF,                   WAKEUP_NULL},
};

The structure WakeEvent_TypeDef is defined as follows:

typedef struct {
   u32 Module;
   enum wakeup_mask Wakeup;
} WakeEvent_TypeDef;

• Module: Wake-up source

• Wakeup: Wake-up mask, specifies which CPU to wake up, available options are:

RTL8721DxRTL8720ERTL8710ERTL8726ERTL8713ERTL8730ERTL8721F

• WAKEUP_KM4 : Wake up KM4

• WAKEUP_KM0 : Wake up KM0

• WAKEUP_NULL : Disable this wake-up source

For example, setting {WAKE_SRC_UART0,   WAKEUP_KM4} means UART0 will wake up KM4; Setting {WAKE_SRC_UART0,   WAKEUP_KM0} means UART0 will wake up KM0. The wake-up mask should be set to the CPU running the user’s application, ensuring that both the interrupt and wake-up source are configured for the same CPU.

Note

• If you select to wake up KM4, KM0 will also be awakened.

• The SDK has already configured specific wake-up source masks, which cannot be modified. For example, {WAKE_SRC_WIFI_FISR_FESR_IRQ, WAKEUP_KM0} is dedicated for Wi-Fi and cannot be changed.

Tip

In addition to modifying the sleep_wevent_config[] array, users can also configure wake-up sources using APIs such as SOCPS_SetAPWakeEvent() and SOCPS_SetNPWakeEvent().

Clock and Voltage Configuration

Certain wake-up sources require configuration of parameters such as OSC, XTAL, and MCU core voltage during sleep to function correctly. These parameters can be configured through the ps_config[] structure.

RTL8721DxRTL8720ERTL8710ERTL8726ERTL8713ERTL8730ERTL8721F

When using UART or LOGUART as a wakeup source, the voltage and clock source during sleep need to be modified. The configurable parameters are as follows:

struct PSCFG_TypeDef ps_config = {
   .keep_osc4m_on = FALSE,          /* keep OSC4M on or off for sleep */
   .xtal_mode_in_sleep = XTAL_OFF,  /* set xtal mode during sleep mode, see enum xtal_mode_sleep for detail */
   .sleep_to_08V = FALSE,           /* default sleep to 0.7V, set this option to TRUE will sleep to 0.8V */
};

Sleep Related Parameters

Parameter	Meaning	Description
keep_osc4m_on	Whether OSC4M is on during sleep	TRUE: Keep enabled FALSE: Disabled
xtal_mode_in_sleep	XTAL working mode during sleep	XTAL_OFF: Turn off crystal XTAL_LPS_With_40M: Maintain 40MHz in low power mode
sleep_to_08V	MCU Core voltage during sleep	FALSE: 0.7V (Default) TRUE: 0.8V

Configuration principles are as follows:

1. When developing with Raw API, the following configuration principles apply to UART and LOGUART:

   1. Clock Selection: Call RCC_PeriphClockSource_UART_ROM before sleep to select the clock source:

      • If OSC2M is selected, set keep_osc4m_on = TRUE.

      • If XTAL is selected, set xtal_mode_in_sleep = XTAL_LPS_With_40M.

   2. Voltage Setting: Must be set to sleep_to_08V = TRUE to ensure OSC4M or XTAL works properly.

2. When developing with Mbed API, the following configuration principles apply only to UART:

   1. Clock Selection: Call serial_baud before sleep. The decision is made automatically based on the UART baud rate and low-power settings:

      • When baud rate ≤ 115200 baud/s and .LOW_POWER_RX_ENABLE = ENABLE, OSC2M is automatically selected; need to set keep_osc4m_on = TRUE.

      • When baud rate > 115200 baud/s or .LOW_POWER_RX_ENABLE = DISABLE, XTAL is automatically selected; need to set xtal_mode_in_sleep = XTAL_LPS_With_40M.

      Configuration example:

      UARTCFG_TypeDef uart_config[3] = {
         /* UART0 */
         {
            .LOW_POWER_RX_ENABLE = DISABLE, /* Enable low power RX */
         },
         /* UART1 */
         {
            .LOW_POWER_RX_ENABLE = DISABLE,
         },
         // ...
      };
      

   2. Voltage Setting: The sleep voltage needs to be set to sleep_to_08V = TRUE to ensure OSC4M or XTAL works properly.

Note

Enabling XTAL during sleep will significantly increase power consumption.

Deep Sleep Wake-up Source Configuration

Wake-up Sources

The following wake-up sources can wake up the system from deep sleep mode:

• AON Timer

• RTC

• BOR

• PWR_DOWN

• AON Wakepin

Parameter Configuration

Deep sleep wake-up sources can wake up the system from both deep sleep and sleep modes. No sleep wake-up mask, voltage, or related parameter configuration is required for deep sleep.

Wake Pin Configuration

Wake pins are a group of special GPIOs that can be used to wake up the system from both deep sleep and sleep modes. In sleep mode, wake pins can be multiplexed as GPIOs for GPIO wake-up, or configured as dedicated wake pin functions.

Example code for wake pin configuration can be found at wake pin example.