刚拿到手的2440，开机后插上U盘没反应，U盘是8G的FAT32的，请问怎样可以识别并打开U盘里的文件？

串口出现什么信息？贴出来看看

usb 1-1: new full speed USB device
using s3c2410-ohci and address 2
usb 1-1: New USB device found, idVendor=0dd8, idProduct=1704
usb 1-1: New USB device strings: Mfr=1, Product=2, SerialNumber=3
usb 1-1: Product: OnlyDisk
usb 1-1: Manufacturer: Netac
usb 1-1: SerialNumber: 909112008A02
usb 1-1: configuration #1 chosen from 1 choice
scsi0 : SCSI emulation for USB Mass Storage devices
scsi 0:0:0:0: Direct-Access     Netac    OnlyDisk         PMAP PQ: 0 ANSI: 0 CCS

sd 0:0:0:0: Attached scsi generic sg0 type 0
sd 0:0:0:0: [sda] 15659008 512-byte logical blocks: (8.01 GB/7.46 GiB)
sd 0:0:0:0: [sda] Write Protect is off
sd 0:0:0:0: [sda] Assuming drive cache: write through
sd 0:0:0:0: [sda] Assuming drive cache: write through
sda:
sd 0:0:0:0: [sda] Assuming drive cache: write through
sd 0:0:0:0: [sda] Attached SCSI removable disk

我想在开发板上看U盘里的PDF和视频文件，该怎样做呢？还要做什么设置或者装什么驱动吗？

sd 0:0:0:0: Attached scsi generic sg0 type 0
sd 0:0:0:0: [sda] 15659008 512-byte logical blocks: (8.01 GB/7.46 GiB)
sd 0:0:0:0: [sda] Write Protect is off
sd 0:0:0:0: [sda] Assuming drive cache: write through
sd 0:0:0:0: [sda] Assuming drive cache: write through
sda:
sd 0:0:0:0: [sda] Assuming drive cache: write through
sd 0:0:0:0: [sda] Attached SCSI removable disk

你的U盘不包含一个合法的分区表，因此友善之臂的root_qtopia文件系统镜像没法自动挂载它。理由看这里
http://www.aiothome.net/read.php?tid=1702#5094

你可以尝试在命令行上手动挂载U盘：
#mount /dev/sda /udisk

我不清楚默认的文件系统镜像里有没有PDF的阅读器，如果有的话，用上面的命令挂载U盘后，让阅读器打开/udisk目录应该就能找到U盘上保存的PDF文件了。视频播放器也是一样的。

还是挂不上，返回信息是这
[root@FriendlyARM /]# mount /dev/sda /udisk
mount: mounting /dev/sda on /udisk failed: No such file or directory

我是不是重新换个U盘或许可以呢？

如果没有/dev/sda, 用
#mknod /dev/sda b 8 0

如果没有/udisk, 用
#mkdir /udisk