Confusing Boot Switch Behavior & SD Card Issues

Banana Pi Router design BPI-R4/BPI-R4 Pro(MT7988)
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Hi everyone,

I received my BPI-R4 Pro device today. This is my very first development board and my first experience with OpenWrt, so I am trying to understand if what I experienced is normal behavior or a hardware defect.

The Boot Issue:

  1. I flashed the image to the SD card.
  2. According to the board labels and the Wiki instructions, I set both boot switches to the “Down” position (0-0 for SD Boot).
  3. I tried to boot from the SD card for about an hour, but it refused to boot. No activity.
  4. Finally, I changed the switches to the position shown in the attached photo (Please see attached photo), and it surprisingly booted up.

CleanShot 2025-12-17 at 04.23.03@2x
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The eMMC Confusion: After managing to boot, I flashed the eMMC images via USB.

  • I left the switches in the same “working” position (the one in the photo), and it booted from eMMC.
  • Then, I changed the switches to the “correct” eMMC position according to the Wiki, and it also booted fine.

My Question: This behavior feels inconsistent and confusing. Why did the official Wiki instructions for SD boot fail for me, while a random switch combination worked? Is there a hardware issue with my board’s boot selection, or is the documentation/labeling misleading?

Additional Issue (NVMe): Besides the boot confusion, I am also unable to get my NVMe SSD to show up in the system. I have opened a separate detailed topic for that issue here: NVMe SSD detected in lspci but missing in lsblk - Missing kmod-nvme

Any guidance for a beginner would be appreciated. I want to make sure my hardware is not defective.

Thanks.

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Hello friend, I think you might have turned the wrong switch. SD card boot is 11.

You can start learning R4Pro through the link.

3

I guess boot switches are right (down=1,not 0), more interesting would be the output on debug-uart.

I noticed an issue with my cards when running on full speed (52mhz). This will cause read errors in uboot+linux.

So if this is the problem, you should get into uboot.

As same cards work well in bpi-r4 i reduced the speed a bit in dts to have maximum compatibility.