想用 sunxi-fel 刷机，还得用这种 usb 线，MicroUSB 线只能供电用

插之前

# lsusb
Bus 001 Device 002: ID 8087:8001 Intel Corp. 
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 003 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 002 Device 003: ID 8087:0aa7 Intel Corp. 
Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

插之后

# lsusb
Bus 001 Device 002: ID 8087:8001 Intel Corp. 
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 003 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 002 Device 003: ID 8087:0aa7 Intel Corp. 
Bus 002 Device 005: ID 1f3a:efe8 Onda (unverified) V972 tablet in flashing mode
Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

多了一行

Bus 002 Device 005: ID 1f3a:efe8 Onda (unverified) V972 tablet in flashing mode