一、电源
S32K3系列芯片的电源各不相同。以S32K34x,S32K32x及S32K314为例。
并且该芯片支持以下特性:
• Combination of internal and external voltage regulator options, offering RUN and Standby modes
• FPM , which is used on chip-level in RUN modes: For high-current consumption
• LPM , which is used on chip-level for Standby modes: For low-current consumption
• Active POR providing brown-out detect
• LVR for all system-relevant power domains
• LVD and HVD as indication for software
1.1 Reset
上电复位POR和低电压复位LVR都会导致芯片复位,具体原因可以通过寄存器PMC_LVSC查看。寄存器中的标志位相关的复位标志不会被复位影响,因此需要及时对这些标志位进行清除。
1.2 Interrupt
PMC包括两个中断:
• HVD interrupt: Combines all HVD monitors into one interrupt source. CONFIG[HVDIE] enables this interrupt. See PMC
Configuration (CONFIG) and Low Voltage Status And Control (LVSC) for details.
• LVD interrupt: The LVD5A monitor is the only interrupt source. CONFIG[LVDIE] enables this interrupt. See PMC
Configuration (CONFIG) and Low Voltage Status And Control (LVSC) for details.
1.3 Regulator
PMC包括了三个Regulator:
• a low-power regulator ( LPM ) supplying core logic during Standby mode ( V11_STANDBY ),The LPM regulator manages the chip in Standby mode.
• Boot (Applicable for S32K344/S32K324/S32K314 and S32K3x2), The boot regulator manages the chip during the booting process.
• Last-mile ( FPM ),The last-mile regulator is the full-performance regulator, which you enable for running applications.
1.3.1 1.5V Source
1.3.2 PMC last-mile regulator auto-enable feature(不同复位发生导致Regulator发生变化)
需要注意的是,当从Stamdby退出时,需要打开Last Mile Regulator;当进入到Standby时,需要关闭Last Mile Regulator。
当我们第一次上电时,一直使用的是Boot Regulator,上电完成之后进入到main函数之后,可以通过配置的方式,使用 Last Mile Regulator,Solved: S32K344 Last Mile Regulator - NXP Community。
二、复位
2.1 类型
复位主要包括三类:
• Power-on reset
− The complete device gets reset when power is applied
− All PMC (Power Management Controllers) POR and LVRs are combined into one single MCU POR.
• Destructive reset
− associated with a critical error or dysfunction.
− full reset sequence applied, starting from DEST0, ensuring a safe start-up state for both digital and analog modules. The memory content must be considered to unknown state.
• Functional reset
− associated with a less-critical error or dysfunction
− partial reset sequence applied, starting from FUNCm0. Most digital modules are reset normally, while the state of analog modules or specific digital modules (for example, debug modules, flash modules) as well as the system memory content is preserved.
具体复位原因,参考1.1。