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Most scanners use slower versions of scsi, and 8 bits at that. > -----Original Message----- > From: firstname.lastname@example.org [mailto:email@example.com]On Behalf Of > Paul Corsa > Sent: Thursday, May 16, 2002 3:11 AM > To: firstname.lastname@example.org > Subject: Re: Polaroid Sprintscan 4000 connectivity > > > The list must have forgotten the 80 and 160MBps SCSI versions? In > any event, most > scanners don't need more than 20MBps, so the optimum choices are still > SCSI-2(wide) or more current ; and Firewire; both much faster > than USB1.1. No > current scanners output via USB 2 to my knowledge. Paul > > "James E. Martz" wrote: > > > OK. I went to the Epson site to see what they had to say about > it. They > > have a PDF file on their documentation page at: > > > <http://support.epson.com/hardware/scanner/per245/documentation.html> > > called "Epson Answers (Scanners)" which addresses transfer speeds. It > > gives the following speeds for various interfaces: > > > > Standard parallel 0.115 MBps > > ECP/EPP parallel 3 MBps > > USB 1.1 1.5 MBps > > USB 2.0 60 MBps > > SCSI 5 MBps > > SCSI-2 (narrow) 10 MBps > > SCSI-2 (wide) 20 MBps > > Firewire (IEEE 1394) 12.5 to 50 MBps > > > > According to this, USB 2.0 is the speed winner and the way the > page reads, > > I think I would be justified in being peeved if my Perfection > 2450 didn't > > operate at USB 2.0 speeds if I had a USB 2.0 port on my computer. > > > > At 11:32 AM 5/14/2002 -0500, Laurie Solomon wrote: > > >Jim, > > >I probably should have prefaced that remark with "to the best of my > > >knowledge." :-) > > > > > >At any rate, I have found in many cases a claim to be > compatible with USB > > >2.0 often means it will run off a USB 2.0 card but as a USB > 1.1; but the > > >device itself is not usually 2.0. While as time proceeds some > devices may > > >be put on the market which actually are 2.0; but I suspect they will > > >advertise in bold letters not "compatible with" but "USB 2.0." > Today, most > > >of the add-in cards and even the USB portions of the newer > motherboards are > > >2.0 with backward compatibility; but they are somewhat ahead of the > > >peripheral devices that might connect to them. > > > > The page says that USB 2.0 is backward and forward compatible, > meaning that > > a USB 1.x device will work plugged into a USB 2.0 port on a > computer, and > > that a USB 2.0 device will work plugged into a USB 1.x port on > a computer - > > only they will both work at the slower speed. > > > > >-----Original Message----- > > >From: email@example.com [mailto:firstname.lastname@example.org]On Behalf Of > > >James E. Martz > > >Sent: Tuesday, May 14, 2002 7:34 AM > > >To: email@example.com > > >Subject: RE: Polaroid Sprintscan 4000 connectivity > > > > > > > > >At 12:15 AM 5/14/2002 -0500, Laurie Solomon wrote: > > > >Unless the USB card is one that utilizes the USB 2 standard, > it will not be > > > >faster than the SCSI connection. If it is a USB2 card, at > present there > > >are > > > >no scanners or any other peripherals that use USB2. > > > > > >My Epson Perfection 2450 Photo claims to compatible with USB > 2.0. Can't > > >tell if it actually operates at 2.0 speeds since my computers > only have 1.x. > > > > > > > **************** > > James E. Martz > > Milan, OH > > firstname.lastname@example.org > > ***************** > > > > - > > Turn off HTML mail features. Keep quoted material short. Use accurate > > subject lines. http://www.leben.com/lists for list instructions. > > - > Turn off HTML mail features. Keep quoted material short. Use accurate > subject lines. http://www.leben.com/lists for list instructions. > - Turn off HTML mail features. Keep quoted material short. Use accurate subject lines. http://www.leben.com/lists for list instructions.