Hi there…
So if it goes into bootloader mode and the bootloader is not corrupt,
why not just Drag and drop?
The Seeed XIAO RA4M1 board uses the UF2 bootloader developed by Adafruit, customized for the Renesas RA4M1 chip. It allows:
- Drag-and-drop programming via USB (mounts as a mass storage device)
- Arduino/PlatformIO compatibility
- Double-tap reset to enter bootloader mode
Bootloader Highlights:
| Feature | Description |
|---|---|
| Type | UF2 Bootloader (mass storage + serial) |
| Chip | Renesas RA4M1 (Arm Cortex-M4, 48 MHz) |
| Flashing Method | UF2 file over USB (drag & drop) or via SWD/debugger |
| Boot Mode | Entered by double-pressing reset or holding BOOT button while powering |
| Source | Based on Adafruit’s UF2 bootloader, maintained in Seeed’s fork or BSP repo |
If you’re flashing it from scratch (e.g., after a full erase), you’ll need a debug programmer like a J-Link or DAPLink, and Seeed provides the precompiled .uf2 bootloader file on their GitHub or wiki pages.
HTH
GL 
PJ 
Summary: In normal situations, use a quick double-tap of RESET to access the UF2/DFU bootloader (the board will show up as a firmware-upload port in Arduino IDE, e.g. “XIAO RA4M1 Firmware Upgrade”github.com). If that fails (e.g. bootloader is corrupted), use the BOOT button + reset/power to invoke the chip’s internal DFU for emergency recovery.