Randall Hyde <firstname.lastname@example.org> wrote:
If you are new to USB, I’d heartily recommend reading the USB specs and
familiarize yourself with them first. I’d also recommending reading the 1.1
specs rather than the 2.0 specs. The 1.1 specs contain most of the software
info you’ll need to know for typical embedded apps without the complexity of
the high-speed stuff that really complicates things. If you need high-speed
operation, read the 2.0 specs after you digest the 1.1 stuff.
Excellent suggestion, I was googling for some information on the net about
these things and everything came up short on details. I did download the 1.1
spec but have not yet looked at it. I will now.
As for that high-speed USB 2 crap, I hope to never use it and would always
choose firewire over USB2.
To be honest, storage class device drivers are among the more complex
class drivers in USB (there are worse, but the storage class is not where
I’d start when learning USB, indeed, I wouldn’t start with class drivers at
Well, techinically, I don’t care about making a class driver, I’ll be happy
with a driver that can read and write blocks (not files) to/from the specific
unit that I have.
Hopefully, you’re already familiar with the SCSI protocol, since USB
storage devices (usually) tunnel SCSI commands through the USB
Somewhat, I’ve never had to do much with it, until now.
The source that Phil provided was great, it got me much farthur than the
actual DDK docs did. I was able to duplicate most of the output of the
USB command (at least for my device) and now have a bit better understanding
of how things work in the world of USB. That should hopefully make reading
the 1.1 spec easier too.
I heard QSSL is working on a storage class driver.
I have heard similiar rumors, and I am eagerly anticipating it. The USB DDK
has been around for a long time now, with its start in qnx4, it’s almost
embarrasing that it has taken this long (QNX 6.2.1) to finally have USB mouse
and keyboards auto-detected. I think that there is tremendous demand out
there for USB mass-storage devices (since USB keyrings are now becoming quite
common), as well as for USB networking hardware. Those two areas of USB
are where QNX desperately needs more support.
Of course, there are the Linux sources, but they have Linux file manager
junk intertwined (and suffer from GPL, poor documentation, etc., etc.).
I’ve tried to look at some of those, and man…
Martin Zimmerman email@example.com
Camz Software Enterprises www.passageway.com/camz/qnx/
QNX Programming & Consulting www.qnxzone.com