boot0sio working for anyone?

Scott Long scottl at
Fri Feb 8 20:38:48 UTC 2008

Bruce M. Simpson wrote:
> Ulrich Spoerlein wrote:
>> So, is boot0sio supposed to just work with a cheap USB->RS232 dongle at
>> the other end? I don't know how this paragraph from boot0cfg(8) is
>> affecting me.
> boot0sio is wholly dependent upon BIOS support for addressing the 
> on-board COM1 port. It is not intended (read: very unlikely) to work 
> with USB dongles.
> If your BIOS does not support the call that it uses, then the symptoms 
> will be similar to what you've seen. Unfortunately there is just not 
> enough space in the MBR to implement any workarounds for this.

Yeah, unless the BIOS provides traditional SIO emulation via USB 
(similar idea to providing tradition AT keyboard emulation via USB)
then boot0sio won't work.  It's not very feasible to put a USB
stack into the early boot loader anyways.  It's somewhat possible
(at least, using a chained boot loader), but not very feasible.


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