在MSP432P401R RTOS中，如何将clock source由Clock System改为 WDT_A (in interval timer mode) ?

根据您的描述，您应该是想在LPM3下继续使用定时器且保持空闲时低功耗？您可以参考下面的文章

processors.wiki.ti.com/.../TI-RTOS_MSP432_Timer

The basic idea is to use the watchdog timer to drive the TI-RTOS' Clock tick. This is accomplished by the following steps.

1 Tell TI-RTOS that the Clock tick will be driven by the application. This is accomplished in the TI-RTOS configuration file (.cfg).

2 Create a Hwi for the watchdog timer. This can be done during runtime execution or via the TI-RTOS configuration file (.cfg). For this example, we'll create it in the configuration file.

3 Enable the watchdog during runtime.

4 Restrict the DEEPSLEEP_1 (aka LPM4) mode, otherwise the watchdog is deactivated when entering that mode. The power savings between DEEPSLEEP_0 and DEEPSLEEP_1 is small.

5 Have the Hwi function call Clock_tick() to drive the Clock modules internal timing.