Mystery of the Wake-Up: Debugging MCU Wake-Ups in Apollo3 Using Keil

[yaswanthsk04]

Hello community,

I'm seeking insights into the wake-up mechanism of an Ambiq Apollo3 microcontroller in a specific setup using Keil µVision. The transmission and reception part works seamlessly. Thanks to the team! But the MCU wakes up at exactly the intended times, so I'm puzzled about the specific triggers behind this precise timing. Here are some key details about my setup and what I have observed:

• Device: Ambiq Apollo3
• IDE: Keil µVision
• Application: periodic-uplink-lpp
• Application Version: 1.3.0
• GitHub Base Version: 4.7.0
• Observed Behavior: The microcontroller successfully wakes up at predetermined times, but the explicit source or configuration enabling this is unclear.
• Sleep Mechanism: The controller enters sleep mode via the BoardLowPowerHandler function.
• Debug Strategy: I have placed breakpoints and monitored the NVIC. Despite this, the specific interrupt handling mechanism, especially from potential sources like the LoRa IRQ pin, remains unidentified. No ISR is explicitly written for DIOIRQ which could have been a suspect in handling wake-ups.

I would appreciate any advice or pointers on how to utilize Keil µVision more effectively to uncover the exact wake-up triggers. If anyone has experience with the Apollo3's sleep and wake functionalities or understands how these might be managed internally or through specific configurations, your input would be invaluable.

How can I identify and understand the specific sources or configurations that control the MCU's wake-up timing? Any tips on tools or diagnostic methods for a deeper dive into the MCU's behavior would be greatly appreciated.

Thank you in advance for your help and suggestions!