funny thing - the SDRAM used provides 300kb/sec, while the SDcard used as storage provides 200kb/sec. Performancewise they could just skip most of the ram outside of booting and use the SDcard without losing much performance, especially since the SDRAM needs to be refreshed every 62ms for a duration of 3ms regardless of use.
Edit: I LOVE this part:
It takes about 2 hours to boot to bash prompt ("init=/bin/bash” kernel command line). Then 4 more hours to boot up the entire Ubuntu ("exec init” and then login). Starting X takes a lot longer. The effective emulated CPU speed is about 6.5KHz, which is on par with what you’d expect emulating a 32-bit CPU & MMU on a measly 8-bit micro. Curiously enough, once booted, the system is somewhat usable. You can type a command and get a reply within a minute. That is to say that you can, in fact, use it. I used it to day to format an SD card, for example. This is definitely not the fastest, but I think it may be the cheapest, slowest, simplest to hand assemble, lowest part count, and lowest-end Linux PC. The board is hand-soldered using wires, there is not even a requirement for a printed circuit board.
dmitry.gr/?r=05.Projects&proj=07.+Linux+on+8bit
This guy ran linux on 8-bit microcontroller by emulating a hogher end processor on an 8 bit computer. He also emulated the ram on an SD card.
Slow as heck, but can be done.
funny thing - the SDRAM used provides 300kb/sec, while the SDcard used as storage provides 200kb/sec. Performancewise they could just skip most of the ram outside of booting and use the SDcard without losing much performance, especially since the SDRAM needs to be refreshed every 62ms for a duration of 3ms regardless of use.
Edit: I LOVE this part:
6 hours to get into X is ridiculous
Ok, but with emulation and enough time, you can run any software on as much as a light switch.