如 TO_RETENTION 中所示，MCU 已断电，因此必须在进入 RETENTION 之前配置从 RETENTION 到 ACTIVE 状态的转换。必须根据保持模式的类型来设置 I2C_6 和 I2C_7 触发条件。以下是进入 GPIO RETENTION 状态 (I2C_6=1) 并使用 TPS65941515 GPIO4 将 PMIC 唤醒至 ACTIVE 状态的示例。

Write 0x48:0x85:0x40:0x7F    //I2C_6 is high
Write 0x48:0x34:0xC0:0x3F    //Set GPIO4 to WKUP1 (goes to ACTIVE state)
Write 0x48:0x64:0x08:0xF7    //clear interrupt for GPIO4 falling edge
Write 0x48:0x4F:0x00:0xF7    //unmask interrupt for GPIO4 falling edge
Write 0x48:0x86:0x00:0xFC    //trigger the TO_RETENTION power sequence
After the GPIO4 has gone low and the PMIC returns to the ACTIVE state
Write 0x48:0x86:0x03:0xFC    //Set NSLEEPx bits for ACTIVE state
Write 0x48:0x64:0x08:0xF7    //clear interrupt of GPIO4

以下示例展示了进入 DDR RETENTION 状态 (I2C_7 = 1) 并使用 TPS65941515 RTC 计时器将 PMIC 唤醒至 ACTIVE 状态。

Write 0x48:0x85:0x80:0x7F     // I2C_7 is high
Write 0x48:0xC3:0x01;0xFE     // Enable Crystal
Write 0x48:0xC5:0x05:0xF8     // minute timer, enable TIMER interrupts
Write 0x48:0xC2:0x01:0xFE     // start timer, if the timer values are non-zero clear before starting
Write 0x48:0x86:0x00:0xFC     // trigger the TO_RETENTION power sequence
After the RTC Timer interrupt has occurred and the PMIC returns to the ACTIVE state
Write 0x48:0x86:0x03:0xFC     // Set NSLEEPx bits for ACTIVE state
Write 0x48:0xC5:0x00:0xFB     // disable timer interrupt, clear bit 2
Write 0x48:0xC4:0x00:0xDF     // clear timer interrupt, clear bit 5