These are generally known as Bootloader USB and Rockbox USB
Oops O:) Thanks for the info. Much better explained that way

In bootloader mode, as you are operating in Cowon firmware, so the 'charge indicator' light on the top should show whether or not it is charging.
I didn't know that, I thought that the only way of charging from USB using "Bootloader USB" was turning off the DAP. I'll keep an eye on the light.
In Rockbox mode...
The Features comparison Wiki page says 'Charge via USB: Yes'
However, this forum post says no.
As does this even older topic
no again...
Before asking I did a search and I found the last post you say. Since it was from August 2006, I thought things had changed. And yes, I did read the manual (well, the comparison), but my battery voltage dropped while connected using Rockbox USB, so it didn't seem to charge. That's why I asked, I was confused by the docs. The DAP didn't seem to charge, but then again, I thought that it could be my fault (some obscure config setting I missed, or something like that).
It sems that it could, but it's not implemented yet 
Well, thanks
a lot for your help and explanation. I'll take a look at the sources, but I
don't think I can help with this, I'm afraid, because I don't know how the USB hardware present in the iAudio works. I'll keep waiting, that's nothing I can live without

Raúl