如何不使用SD卡通过USB为BeagleBone Black Rev C刷写新镜像？

Got it, let's walk through how to flash a new image to your BeagleBone Black Rev C without relying on an SD card—all over USB. I’ve done this dozens of times, so here’s the reliable, step-by-step breakdown:

First, gather everything you’ll need:

• Your BeagleBone Black Rev C unit
• A data-capable micro USB cable (skip those cheap charge-only cables—they won’t work for data transfer)
• A computer (I’ll cover Linux, macOS, and Windows steps)
• A pre-downloaded BeagleBone image (stick to official Debian-based images for best compatibility)
• For Windows users: BeagleBone USB drivers (you’ll need these to recognize the board)

First, the universal hardware setup:

1. Power off your BBB completely—unplug all power sources (including USB).
2. Locate the S2 boot switch (right next to the micro USB port on Rev C). Flip both switches to the ON position (toward the board’s onboard LEDs) to enable USB boot mode.

For Linux Users #

1. Open your terminal and install the bmap-tools utility (it’s faster and more reliable than dd):

   sudo apt-get update && sudo apt-get install bmap-tools
   

2. Connect your BBB to your computer via USB, then power it on (the USB cable can supply enough power for this process).
3. Wait 30-60 seconds for your system to detect the BBB—it’ll show up as two USB storage devices (a small boot partition and a larger root partition).
4. Unmount any automatically mounted partitions (replace sdX with your BBB’s device name—use lsblk to verify, double-check you’re not targeting your system drive!):

   sudo umount /dev/sdX1 /dev/sdX2
   

5. Flash the image using bmap-tools (replace your-image.img with your downloaded file name, and sdX with the BBB’s full disk device, not a partition):

   sudo bmaptool copy --nobmap your-image.img /dev/sdX
   

6. Once the flash completes, run sudo sync to ensure all data is written, then unmount the device:

   sudo umount /dev/sdX1 /dev/sdX2
   

7. Disconnect the USB cable, flip the S2 switches back to OFF, and power on your BBB—it’ll boot from the newly flashed image.

For macOS Users #

1. If you don’t have Homebrew installed, set it up first, then install bmap-tools:

   brew install bmap-tools
   

2. Connect your USB-boot-mode BBB to your Mac and power it on.
3. Open Disk Utility, locate the BBB’s disk (labeled something like "BeagleBone"), and note its device name (e.g., /dev/disk2—don’t mix this up with your Mac’s internal drive!).
4. Unmount the disk via terminal:

   diskutil unmountDisk /dev/disk2
   

5. Flash the image (replace placeholders with your actual file and device name):

   sudo bmaptool copy --nobmap your-image.img /dev/disk2
   

6. Run sudo sync to finish writing data, then unmount again:

   diskutil unmountDisk /dev/disk2
   

7. Disconnect USB, reset the S2 switches, and power on the BBB.

For Windows Users #

1. Install the BeagleBone USB drivers—you can grab these from the official BeagleBoard site. For newer Windows versions, you may need to disable driver signature verification temporarily, or use Zadig to install the libusb-win32 driver for the BBB.
2. Download and install Win32 Disk Imager (a simple, reliable tool for flashing disk images).
3. Connect your USB-boot-mode BBB to your PC and power it on.
4. Open Win32 Disk Imager, click the folder icon to select your downloaded .img file.
5. Use the "Device" dropdown to select your BBB’s disk (verify the capacity matches the BBB’s storage—never select your system drive!).
6. Click "Write" and wait for the process to complete (don’t interrupt it!).
7. Once done, click "Exit" and safely eject the BBB’s USB device from Windows.
8. Disconnect USB, flip the S2 switches back to OFF, and power on the BBB.

• Double-check your disk device! Accidentally targeting your computer’s internal drive will erase all your data. Always verify the device name and capacity before flashing.
• Use a good USB cable—charge-only cables won’t let your computer communicate with the BBB. If the board isn’t detected, swap cables first.
• Don’t skip the sync/eject step—pulling the USB early can leave the image incomplete, leading to a non-bootable BBB.
• Give the board time to initialize—it takes 30-60 seconds for the BBB to show up as a USB storage device after powering on.
• Reset the boot switch! After flashing, make sure the S2 switches are back to OFF—otherwise, the BBB will keep trying to boot from USB, which won’t work once you disconnect it.

内容的提问来源于stack exchange，提问作者Anant Vikram Singh