Skip site navigation (1)Skip section navigation (2)
Date:      Tue, 4 Jan 2000 12:20:15 +0100 (CET)
From:      Nick Hibma <n_hibma@webweaving.org>
To:        Nate Williams <nate@mt.sri.com>
Cc:        freebsd-hackers@FreeBSD.ORG
Subject:   Re: USB vs. parallel port
Message-ID:  <Pine.BSF.4.20.0001041215310.2117-100000@localhost>
In-Reply-To: <199912261614.JAA07297@mt.sri.com>

next in thread | previous in thread | raw e-mail | index | archive | help

Whether or not the system is loaded or not depends mainly on what
hardware you have. OHCI tends to load the system a lot less than UHCI
(Intel).

But compared to serial and parallel ports, USB is a lot better. Most of
the transaction is done per DMA and with large quantities it outperforms
both of them in every way. 300Kb/s at less than 1% CPU should be no
problem. I have no idea what the load on the PCI bus is though. That
might be a problem as there are a lot of small transfers over that bus.

By the way, at the moment it is better to have a UHCI controller on
your motherboard. Allthough the OHCI controller is much smarter and more
efficient, support for it is not as stable as the support for UHCI
controllers.

Nick


> A co-worker is looking into buying a printer, and was wondering which
> kind would be better, USB and/or parallel.  (There are also some that do
> both).
> 
> Parallel printers tend to load down the system when busy, but serial
> devices tend to load them down even more, although USB is a whole
> different animal.
> 
> What are the trade-offs?
> 
> Thanks for any help you can provide!
> 
> 
> Nate
> 
> 
> To Unsubscribe: send mail to majordomo@FreeBSD.org
> with "unsubscribe freebsd-hackers" in the body of the message
> 

--
n_hibma@webweaving.org
n_hibma@freebsd.org                                          USB project
http://www.etla.net/~n_hibma/



To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-hackers" in the body of the message




Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?Pine.BSF.4.20.0001041215310.2117-100000>