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From: nospam on 26 Jan 2010 18:54 In article <4b5f6753$0$4802$ba624c82(a)nntp02.dk.telia.net>, Erik Richard S�rensen <NOSPAM(a)NOSPAM.dk> wrote: > This sounds real strange to me. how ironic. > - 7 or 9 devices here doesn't matter... > And even more strange that you have connected both printer and mouse to > the keyboard. connecting the mouse to the keyboard is very common. my printer is too far to reach the computer but it does reach the keyboard. since there are two ports on the keyboard, why not use them. > I don't know which keyboard you're using, but an Apple > keyboard can only deliever 500mAh, and many printers require the full > 800mAh connection. nope. the usb spec states that 500ma is the maximum, but it's actually lower than that for a bus-powered hub, such as the one in a keyboard. furthermore, my printer also plugs into the wall and gets more than enough power from there so it doesn't need any power from the usb port. > > i have a few owc enclosures and none have *both* types of usb ports. > > they generally have a mix of usb, firewire 400, firewire 800 and/or > > esata, but i've yet to see a hard drive with both a type a & b usb > > port. the only way that can occur is if it's *also* a hub, and that > > would be unusual for a basic enclosure. > > You want me to look up each and every model? i want you to back up your claim. that's all. > > the newertech ministack includes a usb and firewire hub (two separate > > hubs for two separate connections), as well as a hard drive. is that > > what you are thinking of? > > I'm talking about that I can use the USB ports even if the MiniStacks > are connected through FW400/800, but it of course requires that the > power is turned ON. no you can't. the built-in usb hub is separate from the built-in firewire hub. if you don't connect the usb uplink to the computer, the usb ports will not be of much use.
From: David Empson on 26 Jan 2010 19:16 Erik Richard S�rensen <NOSPAM(a)NOSPAM.dk> wrote: > nospam wrote: > > Erik Richard S�rensen <NOSPAM(a)NOSPAM.dk> wrote: > >>>> Sure it is. And sure it matters how many UsB devices you connect. It is > >>>> obviously that you've never tried running with more than 1-2 maybe three > >>>> USB external devices at a time. > >>> i have 7 usb devices on my desktop mac. > >> Connected how? I guess not individually - rather by hubs... > > > > actually, i miscounted. there are 4 ports on the mac, one of which > > feeds a 4 port hub, for a total of 7 ports, all of which are in use. > > however, i forgot about the mouse and printer which are plugged into > > the keyboard, for a total of 9 devices using two hubs. i have a 7 port > > hub to replace the 4 port hub, so i have a couple of spare ports, but > > i've managed without, at least so far. > > > >> And you don�'t have any slow down in speed when > >> transferring to/from multi-disks? > > > > nope. > > This sounds real strange to me. - 7 or 9 devices here doesn't matter... > And even more strange that you have connected both printer and mouse to > the keyboard. I don't know which keyboard you're using, but an Apple > keyboard can only deliever 500mAh, and many printers require the full > 800mAh connection. Where did you get this 800 mA figure from? (Not mAh by the way - that's a power rating, not current.) The USB standard allows a maximum current of 500 mA, and the USB keyboard is a self-powered hub, which cannot supply more than 100 mA to attached devices. (There have been rumours that Apple's recent USB keyboards and some Mac models are able to exceed the 500 mA limit for a USB port on the computer for recognised Apple peripherals, and provide up to 500 mA via one port on the keyboard, but I haven't seen anything definitive to confirm that.) Almost all printers have their own power supply and mains cable, so they shouldn't need to draw significant power from USB. Some need 500 mA from USB for no obvious reason other than lazy design. 100 mA should be sufficient. > - I had a HP Color DeskJet 5740, which I at first > connected to the black/silver Apple Pro keyboard on my MacPro, but the > first time I used it, a dialog told me that the printer was unavailable > though the System profiler could see the printer and it was visible in > the 'Printer&Fax controlpane. - As soon as I got beneith and behind the > MacPro with the cable, the printer began to print from the cue... That's because the printer told the computer it needed 500 mA via the USB cable, and the keyboard's hub is only able to supply 100 mA. > - Also my trackball works best on a separate port instead of connecting it > to a keyboard. - And now since I've bought a professional Microsoft > keyboard it isn't possible to connect anything to the keyboard... > > >> - If you claim that it is a veeeery special Mac you're > >> using. I can guarantee you one thing and that /is/ that the speed is > >> slowed down. I have only 3 USB devices connected, keyboard, trackball > >> and scanner. And it's for sure that the speed is slowed down when the > >> scanner is working at the same time as typing in a document! > > > > scanning slows down when you type? > > No, typing is slowed down. - I normally type very fast - apprx. 400 > strokes per minute, and when the scanner is working and I'm typing I can > type lots of letters before they occour in the document. I don't believe this would have anything to do with USB communication bottlenecks. 400 characters per minute is a tiny fraction of the potential throughput of USB (even at its slowest 1.5 Mbps). It is more likely that something on the computer is being tied up while it is processing the scanned data. If the computer is old/slow enough, it could be CPU utiltisation due to the combination of managing the heavy USB traffic from the scanner plus processing the data as it arrives. [snip] > >>> which usb hard drive has both types of ports? > >> The French brand, Archos, some of the Mercury enclosures from OWC and > >> some of the Weiland professional series enclosures. > > > > which ones, specifically? > > > > i have a few owc enclosures and none have *both* types of usb ports. > > they generally have a mix of usb, firewire 400, firewire 800 and/or > > esata, but i've yet to see a hard drive with both a type a & b usb > > port. the only way that can occur is if it's *also* a hub, and that > > would be unusual for a basic enclosure. > > You want me to look up each and every model? How about a link to a single example? > Nope mi friend! But have a look at the pro series from both Weiland and > Mercury... - And else I'll say keep away from the Archos enclosures, - > they are real poor and unstable... The OWC Mercury Elite-AL Pro series do NOT have a piggyback USB type A socket. <http://eshop.macsales.com/shop/firewire/1394/USB/EliteAL/eSATA_FW800_FW 400_USB> (There is a picture of the simpler FW400+USB model on the same page.) This series does, and it specifically states that it has a built-in USB hub. "Mercury Elite-AL Pro Dual-Drive USB 2.0 + USB 2.0 Powered Hub" <http://eshop.macsales.com/shop/usb2/EliteAL/Pro_USB2_hard_drive_with_Hu b> -- David Empson dempson(a)actrix.gen.nz
From: Nick Naym on 26 Jan 2010 19:26 In article 1jcx3fj.mc951l1cccpayN%dcohenspam(a)talktalk.net, Daniel Cohen at dcohenspam(a)talktalk.net wrote on 1/26/10 7:43 AM: > Nick Naym <nicknaym@_remove_this_gmail.com.invalid> wrote: > >> >> Seagate has had a slew of problems these past few years, as evidenced by >> posts in its forums as well as user reports on retailer sites like Newegg. >> Though not alone in this regard -- overall, drive quality has, IMO, >> plummeted because of Industry cost-cutting measures that have resulted in >> increasing reliance on economically distressed offshore suppliers -- I have >> the sense that Seagate has suffered the most. (As you know, JR, the company >> recently slashed its 5-year product warranty to 3 years, using the >> transparently lame excuse that it was doing so simply to be "more in line >> with the rest of the industry.") > > I have a Seagate FreeAgent Desktop drive. It goes to sleep after its own > period of inactivity (NOT controlled by the Energy Saver settings) and > can't be woken again simply. Seagate have a downloadable piece of > software that is supposed to cure this, but I am almost certain it is > wrongly coded and does not do what it is supposed to. I have mentioned > this on the Seagate forums and got no response, although Seagate people > do monitor the forums. There doesn't seem to be a way of asking Seagate > directly about this. Fortunately I found a way round the issue for my > purposes. IIRC, I got an email response from Seagate by requesting help online: http://www.seagate.com/www/en-us/about/contact_us Technical Support > Email >> Additionally, when I got my Barracuda (September, 2008), I was told by a >> Seagate tech that they won't deal with any problems that occur if the drive >> is used in an external enclosure (which, of course, is how I'm using it) -- >> they don't want to get caught up in a finger-pointing contest between >> themselves and the enclosure vendor should a drive problem arise. > > In another discussion of hard drives on one of the Usenet groups, I > commented that this potential issue was a major reason why i bought > ready-built external drives (I have one in my own enclosure, that has > been fine). It may very well be the "common sense" approach to take to avoid risking being left "holding the bag," which is always a very real possibility when trying to resolve technical problems in a multi-vendor environment. I don't know how other drive manufacturers respond to customer claims of drive problems, but in Seagate's case, it's clearly official policy: They won't even engage in a conversation with you if you tell them the drive was installed in an external enclosure. Apparently, Seagate has decided that any drive problem that occurs when the drive is installed in an external enclosure is -- for warranty purposes -- _by definition_ caused by the enclosure. Makes me wonder how they'd deal with a drive problem that occurs when the drive was used to replace an internal drive: Would they have a tendency to conclude that the problem was caused by the computer? -- iMac (24", 2.8 GHz Intel Core 2 Duo, 2GB RAM, 320 GB HDD) � OS X (10.5.8)
From: Erik Richard Sørensen on 26 Jan 2010 20:12 David Empson wrote: > Erik Richard Sørensen <NOSPAM(a)NOSPAM.dk> wrote: >> nospam wrote: >>> Erik Richard Sørensen <NOSPAM(a)NOSPAM.dk> wrote: >>>>>> Sure it is. And sure it matters how many UsB devices you connect. It is >>>>>> obviously that you've never tried running with more than 1-2 maybe three >>>>>> USB external devices at a time. >>>>> i have 7 usb devices on my desktop mac. >>>> Connected how? I guess not individually - rather by hubs... >>> actually, i miscounted. there are 4 ports on the mac, one of which >>> feeds a 4 port hub, for a total of 7 ports, all of which are in use. >>> however, i forgot about the mouse and printer which are plugged into >>> the keyboard, for a total of 9 devices using two hubs. i have a 7 port >>> hub to replace the 4 port hub, so i have a couple of spare ports, but >>> i've managed without, at least so far. >>> >>>> And you donø't have any slow down in speed when >>>> transferring to/from multi-disks? >>> nope. >> This sounds real strange to me. - 7 or 9 devices here doesn't matter... >> And even more strange that you have connected both printer and mouse to >> the keyboard. I don't know which keyboard you're using, but an Apple >> keyboard can only deliever 500mAh, and many printers require the full >> 800mAh connection. > > Where did you get this 800 mA figure from? (Not mAh by the way - that's > a power rating, not current.) From the specs info on the Belkin PCIe USB card and the Belkin UsB hub I have. Here it's stated 500-800mA. And as I read the info on my MacPro it also says up to 800mA. > The USB standard allows a maximum current of 500 mA, and the USB > keyboard is a self-powered hub, which cannot supply more than 100 mA to > attached devices. > > (There have been rumours that Apple's recent USB keyboards and some Mac > models are able to exceed the 500 mA limit for a USB port on the > computer for recognised Apple peripherals, and provide up to 500 mA via > one port on the keyboard, but I haven't seen anything definitive to > confirm that.) At least then I can say that the Intel QuadCore technology claims up to 800mA on the onboard as well as the Belkin PCIe USB card. - And the same does my MDD 1,25ghz on a PowerLogix PowerForce Combo USB+FW PCI card when reading the info in System Profiler (10.4.11+10.5.8) > Almost all printers have their own power supply and mains cable, so they > shouldn't need to draw significant power from USB. Some need 500 mA from > USB for no obvious reason other than lazy design. 100 mA should be > sufficient. Why then the HP dialog? - And I can add here that some years ago with the AGFA SnapScan 1212U and 1236U scanners, Agfa simply told in the setup guide that connecting to the hub in the Apple USB keyboards will result in the scanner won't work. I've also had other printers from HP telling the same in the setup guidelines. Some even told that I '...must use the built-in USB connection' - and '...Do not use a PCI USB card for connecting this unit' (HP white paperes). I tried it many years ago now with a HP PSC 1110. This one wouldn't work unless it was connected to one of the two built-in USB connecitons. Moving it to a built-in PCI card gave the same dialog as mentioned - but beginning with 'No printer available...'. Same recommendation for a PSC 1710, but this one worked fine on a PCI card. My now sold Brother DCP-360n also recommended built-in USB, but worked fine on a PCI card on my PM 9600 and the old Beige G3 with PCI USB card. (Never got it networked before I sold it again). >> - I had a HP Color DeskJet 5740, which I at first >> connected to the black/silver Apple Pro keyboard on my MacPro, but the >> first time I used it, a dialog told me that the printer was unavailable >> though the System profiler could see the printer and it was visible in >> the 'Printer&Fax controlpane. - As soon as I got beneith and behind the >> MacPro with the cable, the printer began to print from the cue... > > That's because the printer told the computer it needed 500 mA via the > USB cable, and the keyboard's hub is only able to supply 100 mA. That was also my conclusion.:-) >>>> - If you claim that it is a veeeery special Mac you're >>>> using. I can guarantee you one thing and that /is/ that the speed is >>>> slowed down. I have only 3 USB devices connected, keyboard, trackball >>>> and scanner. And it's for sure that the speed is slowed down when the >>>> scanner is working at the same time as typing in a document! >>> scanning slows down when you type? >> No, typing is slowed down. - I normally type very fast - apprx. 400 >> strokes per minute, and when the scanner is working and I'm typing I can >> type lots of letters before they occour in the document. > > I don't believe this would have anything to do with USB communication > bottlenecks. 400 characters per minute is a tiny fraction of the > potential throughput of USB (even at its slowest 1.5 Mbps). It is more > likely that something on the computer is being tied up while it is > processing the scanned data. Could be, but why did it then stop, when I moved the scanner to an internal UsB port? - That makes no sense... > If the computer is old/slow enough, it could be CPU utiltisation due to > the combination of managing the heavy USB traffic from the scanner plus > processing the data as it arrives. I wouldn't call a MacPro QuaCore 2,66ghz/9gb RAM an 'old an slow' Mac.:-) >>>>> which usb hard drive has both types of ports? >>>> The French brand, Archos, some of the Mercury enclosures from OWC and >>>> some of the Weiland professional series enclosures. >>> which ones, specifically? >>> >>> i have a few owc enclosures and none have *both* types of usb ports. >>> they generally have a mix of usb, firewire 400, firewire 800 and/or >>> esata, but i've yet to see a hard drive with both a type a & b usb >>> port. the only way that can occur is if it's *also* a hub, and that >>> would be unusual for a basic enclosure. >> You want me to look up each and every model? > > How about a link to a single example? > >> Nope mi friend! But have a look at the pro series from both Weiland and >> Mercury... - And else I'll say keep away from the Archos enclosures, - >> they are real poor and unstable... > > The OWC Mercury Elite-AL Pro series do NOT have a piggyback USB type A > socket. > > <http://eshop.macsales.com/shop/firewire/1394/USB/EliteAL/eSATA_FW800_FW > 400_USB> > > (There is a picture of the simpler FW400+USB model on the same page.) > > This series does, and it specifically states that it has a built-in USB > hub. "Mercury Elite-AL Pro Dual-Drive USB 2.0 + USB 2.0 Powered Hub" > > <http://eshop.macsales.com/shop/usb2/EliteAL/Pro_USB2_hard_drive_with_Hub> I didn't mention anything about connector types on the Mercury Pro series, neither on the MiniStacks. A fact is that I've connected both a MiniStack V3 and a Mercury Elite Pro USB2.0HS/FW400 (not the AL Pro) in daisy-chained FW and then added an UsB stick to the Mercury. The USB stick showed fast and nicely up on the desktop. Afterwards I tried the same with the V3, and again the stick showed up on the desktop. My own Mercury enclosures are all the Mercury Elite Pro Firewire only (P-ATA version), but the dual one was one that I bought to a friend along with some other stuff from OWC. Cheers, Erik Richard -- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Erik Richard Sørensen, Member of ADC, <mac-manNOSP(a)Mstofanet.dk> NisusWriter - The Future In Multilingual Text Processing - www.nisus.com OpenOffice.org - The Modern Productivity Solution - www.openoffice.org ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
From: nospam on 26 Jan 2010 20:32
In article <4b5f9311$0$8552$ba624c82(a)nntp06.dk.telia.net>, Erik Richard S�rensen <NOSPAM(a)NOSPAM.dk> wrote: > > Where did you get this 800 mA figure from? (Not mAh by the way - that's > > a power rating, not current.) > > From the specs info on the Belkin PCIe USB card and the Belkin UsB hub > I have. Here it's stated 500-800mA. which belkin card is this? the usb spec states 500 ma maximum, but some hosts might provide more current for non-compliant devices such as hard drives. additional power is not part of the usb spec and not guaranteed. > And as I read the info on my MacPro > it also says up to 800mA. bullshit. <http://developer.apple.com/legacy/mac/library/documentation/HardwareDri vers/Conceptual/HWTech_USB/Articles/usb_implementation.html> The Mac Pro has an internal USB 2.0 controller... Each external USB port supports 500 mA at 5 V for 2.5 W. Devices plugged into each port are expected to follow the USB standard for power limits and management. If a device is added that exceeds the per-port current limit, the port will be disabled, but the other ports will continue to function. |