Can ArchLinuxARM boot from USB?

[jGrey]

Hello Experts,

This Subject is my first question, and I raised it on other communities and got the answer was negative. I have two iMX233
Olinuxino-Micros and would like to boot the module from my USB stick. Tried many attempts but no luck. Some experts suggested
to use U-boot firstly boot from the default SD card then execute the kernel in RAM. I did the web search to understand the idea of U-boot, during search, I found the page of http://archlinuxarm.org/platforms/armv5/olinuxino with the title of Install to a micro SD card. WOW! This web page is really my hometown! Today, I followed the instructions to install the U-boot image to my 2GB USB stick, but the same error message displayed -- 0x80502004. I don't understand why? Based on the info that I searched from http://en.wikipedia.org/wiki/Comparison_of_boot_loaders, that info told me that Das U-boot should be able to boot from
USB.

My 2nd question is, when the iMX233 is booted from the micro-SD card, the linux kernel should be loaded to the RAM and be
executing commands from there. But I found that most commands can NOT be executed if the micro-SD card is removed. Why?
And if it is possible to move some functions to the RAM such that the iMX233 still works when the SD card is removed. One example is to read/write/edit to the second micro-SD card by using vi.

Your ideas/answers/suggestions are highly appreciated! Thanks.