Re: Why do not CRT/LCD monitors come with USB?

On Thu, 24 Jul 2008 11:36:44 -0600 Joe Pfeiffer <pfeiffer@xxxxxxxxxxx> wrote:

| phil-news-nospam@xxxxxxxx writes:
|>
|> We need a new kind of interface. Existing ones like USB, Firewire, and SATA,
|> were designed for specific purposes original and were, or will be,
|> repurposed
|
| Ummm, USB? USB most definitely designed from the ground up to be used
| for a wide variety of devices.

It started as an interface to attach phones. Then it was added on to do
a few computer input devices. It wasn't until USB 2.0 that speed finally
became practical for things like disk storage.

USB had to completely change the way the OS drivers worked to go to 2.0.
It wasn't simply a case of being faster within the same protocol. It had
to change the protocol, too. The next speed higher will require a new
protocol.

A better design would be an interface between driver and hardware that just
goes faster when the hardware can deliver faster. The driver gives the
command to send a message and in the newer faster model, the interrupt for
completion of command comes back sooner. The meta registers that tell the
driver what speed would have a HUGE range capacity (like a 64-bit number)
beyond anyone's imagination.

USB also slows down substantially through hubs. It can't keep data moving
along and switch it in the hub at the same time.

USB device addressing is flaky in design. Plug in a disk, unplug it, then
plug the same disk back in to the same port, and it has a different address.

USB is not very graceful in hotplugging. It can't figure out what is going
on instantly. Firewire beats USB big time, and even Firewire is poor.


|> for other things. That's really not very good design. Something that is
|> designed to allow _any_ kind of devide from the outset, with _standard_
|> protocols included for a large variety of device uses (only ONE driver is
|> needed for any one class of device, regardless of manufacturer or
|> model),
|
| A compliant USB device of a particular class can be used with a
| generic driver. The device may implement additional functionality
| which requires a special driver, but core functionality can be
| accessed without it (yes, I know Windows tends to not realize this.
| That's not a weakness in USB).

So why does the old OHCI driver not "just work" at faster speeds when a faster
USB port is used with a faster device? Why are there different drivers.

When 3200 bps USB comes out, will the same existing driver work even at the
new speed?

Yes, there are standards for many devices on USB. But there still appear to
be a number of issues. Maybe manufacturers (like Seagate) just don't do USB
right? Why even give such leeway? Apparently there is a lack of specification
on disk drive spin down in USB.

--
|WARNING: Due to extreme spam, googlegroups.com is blocked. Due to ignorance |
| by the abuse department, bellsouth.net is blocked. If you post to |
| Usenet from these places, find another Usenet provider ASAP. |
| Phil Howard KA9WGN (email for humans: first name in lower case at ipal.net) |
.

Relevant Pages