Robert Rolf whined:
> And why do I have to add a separate and distinct 'device driver'
> for EVERY new device, unlike RS232 or firewire, where the
> application talks to ONE STANDARDIZED API?

Because USB was meant to be idiot proof at the *user* end.  And yes, this
comes at the cost of added complexity for software drivers and devices
themselves.

The driver model allows multiple devices to share the same bus but each look
like a separate device to an app.  It also prevents one app from talking to
an unrelated device just because it happens to be connected to the single
port.  Note that RS-232 is point to point, so you need a separate port for
each concurrently connected device.  And *you* have to keep track of which
devices are connected to which COM ports.  If you tell an app to talk to COM
1 when a different device is plugged in there, too bad.  It might hang,
report an error, or worse, cause the other device to behave in an
undesirable way.

If you're just trying to have your PC talk to a custom gizmo in the lab,
RS-232 is certainly a lot simpler.  However, if you are building devices for
unsophisticated end users, USB is way easier for the customer and for you to
support.  That's exactly what it's purpose is.

> And if one has used a few dozen different devices over time,
> one is stuck with ALL those drivers being loaded by Winblows,
> even if the device is now in the dumpster.

Yeah, that's a tough problem.  It might take up a whole Mbyte or two of disk
space.  I'd mail you a penny which now buys about 10Mbytes of disk space if
I didn't have to spend $.39 postage to get it there.  And note that these
drivers don't take up space in memory until the device is first used.

> Who has been burned so many times by crap USB drivers/devices that
> he has sworn off USB.

Yes, as with any technology, it's possible to create bad implementations.
Of course the only logical answer is to avoid the technology itself.  I
suppose you shouldn't own a car either because Cheverolet once built the
Vega.  I advise against ball point pens too.  I've had some that leaked and
made a mess in my pocket.


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