Hi. The Apollo3 does not support USB natively and therefore/also does not have a USB bootloader. There are at least three ways to re-flash the Apollo3
- Use the UART bootloader that exists permanently on the chip. (Uses USB->UART bridge chip onboard most Artemis boards, or external FTDI USB->UART on the Edge board). A python script to perform this is available in the AmbiqSuite SDK. Another version (slightly modified for simplicity) is available in the Arduino Apollo3 repository on GitHub.
- Use a SEGGER J-Link (or other SWD capable debug probe) to directly flash the memory. Use J-Flash Lite or similar SW along with debug probe HW.
- Use the Ambiq Over-The-Air examples for wireless (Bluetooth) re-programming. Documentation for this exists within the AmbiqSuite SDK
P.s. the Arduino IDE supports all functionality that the HAL does - all HAL functions are available in Apollo3 Arduino sketches. Be aware, however, that the Arduino environment may enable peripherals behind the scenes. These should be disabled for extremely low power examples.
Some helpful links, perhaps?
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