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How to get full USB bus power from a hub?
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eastwind
Mar 3, 2013, 7:37:04 PM3/3/13
to
I have a couple of USB devices that are bus-powered. One is a Seagate
portable hard drive and another is a Memorex "Slim" lightscribe DVD
burner.
In both cases, the devices seem to need the full bus power. Unpowered
USB hubs don't do the trick.
The Seagate makes funny noises and won't mount unless it is plugged
directly into my PowerMac G5's high-speed USB port. Furthermore, when
plugged into my laptop, same thing if the laptop is running off battery
power rather than AC (and even then, it sometimes suddenly disconnects).
The Memorex has a Y-cable, taking up _two_ USB ports! Again, it won't
burn and it won't even mount a disc unless it is plugged directly into
the ports.
Problem is: My G5 has only three USB ports total (any of which can be
high-speed) and my laptop has only two USB ports, only one of which is
high-speed. Where am I supposed to plug in my keyboard and anything
else? I need a hub that will deliver the same voltage as the busses.
I've tried two different el-cheapo "AC-powered" USB 2.0 hubs, but
neither one helps.
I have an old Dr. Bott USB hub that does do the trick, but it's USB
1.1, not high-speed 2.0. There are several Dr. Bott devices on eBay,
but no USB 2.0 hubs. Do they even exist? Having tried other brands with
no success, I don't know which, if any, brands to trust.
Any recommendations? Thanks.
portable hard drive and another is a Memorex "Slim" lightscribe DVD
burner.
In both cases, the devices seem to need the full bus power. Unpowered
USB hubs don't do the trick.
The Seagate makes funny noises and won't mount unless it is plugged
directly into my PowerMac G5's high-speed USB port. Furthermore, when
plugged into my laptop, same thing if the laptop is running off battery
power rather than AC (and even then, it sometimes suddenly disconnects).
The Memorex has a Y-cable, taking up _two_ USB ports! Again, it won't
burn and it won't even mount a disc unless it is plugged directly into
the ports.
Problem is: My G5 has only three USB ports total (any of which can be
high-speed) and my laptop has only two USB ports, only one of which is
high-speed. Where am I supposed to plug in my keyboard and anything
else? I need a hub that will deliver the same voltage as the busses.
I've tried two different el-cheapo "AC-powered" USB 2.0 hubs, but
neither one helps.
I have an old Dr. Bott USB hub that does do the trick, but it's USB
1.1, not high-speed 2.0. There are several Dr. Bott devices on eBay,
but no USB 2.0 hubs. Do they even exist? Having tried other brands with
no success, I don't know which, if any, brands to trust.
Any recommendations? Thanks.
nospam
Mar 3, 2013, 7:55:06 PM3/3/13
to
In article <2013030318...@news.west.earthlink.net>, eastwind
wrote:
> I have a couple of USB devices that are bus-powered. One is a Seagate
> portable hard drive and another is a Memorex "Slim" lightscribe DVD
> burner.
>
> In both cases, the devices seem to need the full bus power. Unpowered
> USB hubs don't do the trick.
they need more than the full power, which is why you're having problems.
> The Seagate makes funny noises and won't mount unless it is plugged
> directly into my PowerMac G5's high-speed USB port. Furthermore, when
> plugged into my laptop, same thing if the laptop is running off battery
> power rather than AC (and even then, it sometimes suddenly disconnects).
>
> The Memorex has a Y-cable, taking up _two_ USB ports! Again, it won't
> burn and it won't even mount a disc unless it is plugged directly into
> the ports.
>
> Problem is: My G5 has only three USB ports total (any of which can be
> high-speed) and my laptop has only two USB ports, only one of which is
> high-speed. Where am I supposed to plug in my keyboard and anything
> else? I need a hub that will deliver the same voltage as the busses.
the port speed isn't what matters, it's how much power it can source.
recent computers can source more than the 500ma usb limit, for this
reason.
> I've tried two different el-cheapo "AC-powered" USB 2.0 hubs, but
> neither one helps.
maybe try something better than an el-cheapo. be sure it can source
more than 500 ma per port.
> I have an old Dr. Bott USB hub that does do the trick, but it's USB
> 1.1, not high-speed 2.0. There are several Dr. Bott devices on eBay,
> but no USB 2.0 hubs. Do they even exist? Having tried other brands with
> no success, I don't know which, if any, brands to trust.
>
> Any recommendations? Thanks.
usb 2 can't source enough power for many devices, especially on older
computers. that's why the hard drive has a dual cable, to get more
power than would otherwise be available.
the answer is to get a newer computer that overspecs the usb ports or
get peripherals that use firewire, which has a much higher power
budget.
wrote:
> I have a couple of USB devices that are bus-powered. One is a Seagate
> portable hard drive and another is a Memorex "Slim" lightscribe DVD
> burner.
>
> In both cases, the devices seem to need the full bus power. Unpowered
> USB hubs don't do the trick.
> The Seagate makes funny noises and won't mount unless it is plugged
> directly into my PowerMac G5's high-speed USB port. Furthermore, when
> plugged into my laptop, same thing if the laptop is running off battery
> power rather than AC (and even then, it sometimes suddenly disconnects).
>
> The Memorex has a Y-cable, taking up _two_ USB ports! Again, it won't
> burn and it won't even mount a disc unless it is plugged directly into
> the ports.
>
> Problem is: My G5 has only three USB ports total (any of which can be
> high-speed) and my laptop has only two USB ports, only one of which is
> high-speed. Where am I supposed to plug in my keyboard and anything
> else? I need a hub that will deliver the same voltage as the busses.
recent computers can source more than the 500ma usb limit, for this
reason.
> I've tried two different el-cheapo "AC-powered" USB 2.0 hubs, but
> neither one helps.
more than 500 ma per port.
> I have an old Dr. Bott USB hub that does do the trick, but it's USB
> 1.1, not high-speed 2.0. There are several Dr. Bott devices on eBay,
> but no USB 2.0 hubs. Do they even exist? Having tried other brands with
> no success, I don't know which, if any, brands to trust.
>
> Any recommendations? Thanks.
computers. that's why the hard drive has a dual cable, to get more
power than would otherwise be available.
the answer is to get a newer computer that overspecs the usb ports or
get peripherals that use firewire, which has a much higher power
budget.
Malcolm
Mar 3, 2013, 10:35:55 PM3/3/13
to
provide 1 amp.
<http://store.apple.com/us/product/MD810LL/A/apple-5w-usb-power-adapter>
eastwind
Mar 4, 2013, 7:23:08 PM3/4/13
to
inclined to sink more money into trying to find one that can meet the
source requirement. Most ads and packaging are silent on this matter
(wonder why?), and I've already learned that price is no guarantee of
better performance. Have you any specific brands to recommend?
>
>> I have an old Dr. Bott USB hub that does do the trick, but it's USB
>> 1.1, not high-speed 2.0. There are several Dr. Bott devices on eBay,
>> but no USB 2.0 hubs. Do they even exist? Having tried other brands with
>> no success, I don't know which, if any, brands to trust.
>>
>> Any recommendations? Thanks.
>
> usb 2 can't source enough power for many devices, especially on older
> computers. that's why the hard drive has a dual cable, to get more
> power than would otherwise be available.
>
> the answer is to get a newer computer that overspecs the usb ports or
> get peripherals that use firewire, which has a much higher power
> budget.
Sorry, getting a newer computer is not the answer for me. The devices
>> I have an old Dr. Bott USB hub that does do the trick, but it's USB
>> 1.1, not high-speed 2.0. There are several Dr. Bott devices on eBay,
>> but no USB 2.0 hubs. Do they even exist? Having tried other brands with
>> no success, I don't know which, if any, brands to trust.
>>
>> Any recommendations? Thanks.
>
> usb 2 can't source enough power for many devices, especially on older
> computers. that's why the hard drive has a dual cable, to get more
> power than would otherwise be available.
>
> the answer is to get a newer computer that overspecs the usb ports or
> get peripherals that use firewire, which has a much higher power
> budget.
are recent purchases, but the computers, though older, serve all my
current needs and I'm not in the market to upgrade just for the sake of
a couple devices that don't adhere to the USB spec. I was hoping a
properly powered hub would be _a_ solution. Are you saying it's not?
(By the way, I looked for firewire devices, which I prefer, but there
are far fewer of them out there. You can't buy what they don't make.)
Thanks,
Stephen
nospam
Mar 4, 2013, 8:59:50 PM3/4/13
to
In article <2013030418...@news.west.earthlink.net>, eastwind
wrote:
> Sorry, getting a newer computer is not the answer for me. The devices
> are recent purchases, but the computers, though older, serve all my
> current needs and I'm not in the market to upgrade just for the sake of
> a couple devices that don't adhere to the USB spec. I was hoping a
> properly powered hub would be _a_ solution. Are you saying it's not?
a hub *could* be a solution but it doesn't have to be. usb 2 only
requires sourcing 500ma, which is not sufficient to spin up a hard
drive or dvd drive.
as i said, recent computers source more power on usb because of this
and some hubs might as well, but there's no requirement that they do
so.
this hub sounds like it will work, but i have not tested it. it claims
one port can source 2.1 amps, which will charge an ipad. 2a is more
than enough for a hard drive or dvd. unfortunately, it's just one port
and you have more than one device.
<http://eshop.macsales.com/item/Newer%20Technology/USB2HB7PRO/>
> (By the way, I looked for firewire devices, which I prefer, but there
> are far fewer of them out there. You can't buy what they don't make.)
there are plenty of firewire devices, although you generally have to
order them online. stores have limited shelf space and don't always
stock them.
often, an external case will have both usb and firewire and sometimes
esata too. you could buy a replacement enclosure and swap the actual
hard drive or dvd drive mechanism. that could be a cheap solution.
another possibility is get an external 5v power supply for the drives.
i've yet to see an external usb enclosure that lacks a dc in port. even
firewire enclosures have power ports.
wrote:
> Sorry, getting a newer computer is not the answer for me. The devices
> are recent purchases, but the computers, though older, serve all my
> current needs and I'm not in the market to upgrade just for the sake of
> a couple devices that don't adhere to the USB spec. I was hoping a
> properly powered hub would be _a_ solution. Are you saying it's not?
requires sourcing 500ma, which is not sufficient to spin up a hard
drive or dvd drive.
as i said, recent computers source more power on usb because of this
and some hubs might as well, but there's no requirement that they do
so.
this hub sounds like it will work, but i have not tested it. it claims
one port can source 2.1 amps, which will charge an ipad. 2a is more
than enough for a hard drive or dvd. unfortunately, it's just one port
and you have more than one device.
<http://eshop.macsales.com/item/Newer%20Technology/USB2HB7PRO/>
> (By the way, I looked for firewire devices, which I prefer, but there
> are far fewer of them out there. You can't buy what they don't make.)
order them online. stores have limited shelf space and don't always
stock them.
often, an external case will have both usb and firewire and sometimes
esata too. you could buy a replacement enclosure and swap the actual
hard drive or dvd drive mechanism. that could be a cheap solution.
another possibility is get an external 5v power supply for the drives.
i've yet to see an external usb enclosure that lacks a dc in port. even
firewire enclosures have power ports.
John Varela
Mar 5, 2013, 1:52:23 PM3/5/13
to
On Mon, 4 Mar 2013 00:37:04 UTC, eastwind wrote:
> In both cases, the devices seem to need the full bus power. Unpowered
> USB hubs don't do the trick.
Have you tried using a powered hub?
> In both cases, the devices seem to need the full bus power. Unpowered
> USB hubs don't do the trick.
--
John Varela
nospam
Mar 5, 2013, 7:13:33 PM3/5/13
to
In article <51W5y0sPNk52-pn2-JfZ8mf17rxsd@localhost>, John Varela
<newl...@verizon.net> wrote:
> > In both cases, the devices seem to need the full bus power. Unpowered
> > USB hubs don't do the trick.
>
> Have you tried using a powered hub?
he said he tried a couple but they didn't work.
> > In both cases, the devices seem to need the full bus power. Unpowered
> > USB hubs don't do the trick.
>
> Have you tried using a powered hub?
Bread
Mar 10, 2013, 1:00:03 PM3/10/13
to
On 2013-03-04 00:55:06 +0000, nospam said:
> In article <2013030318...@news.west.earthlink.net>, eastwind
> wrote:
>
>
>> I've tried two different el-cheapo "AC-powered" USB 2.0 hubs, but
>> neither one helps.
>
> maybe try something better than an el-cheapo. be sure it can source
> more than 500 ma per port.
Definitely a matter of not using el-cheapo. I have a (still quite
> In article <2013030318...@news.west.earthlink.net>, eastwind
> wrote:
>
>
>> I've tried two different el-cheapo "AC-powered" USB 2.0 hubs, but
>> neither one helps.
>
> maybe try something better than an el-cheapo. be sure it can source
> more than 500 ma per port.
inexpensive) D-link one which indicates that a couple of the USB ports
are powered and others are not. And the powered ports work great with
every device I've plugged in (though in fairness, the only ones which
look for power are the iPad (where the power is optional, but helps if
you want to charge), and a pocket-sized hard drive.
I'd previously used an el-cheapo USB hub - powered, supposedly - and it
was worthless.
You don't have to pay top dollar, but in my experience, you cannot get
away with the very cheapest here, either.
TaliesinSoft
Mar 11, 2013, 12:16:47 AM3/11/13
to
On 2013-03-10 17:00:03 +0000, Bread said:
[commenting on obtaining USB power from a hub]
> Definitely a matter of not using el-cheapo. I have a (still quite
> inexpensive) D-link one which indicates that a couple of the USB ports
> are powered and others are not. And the powered ports work great with
> every device I've plugged in (though in fairness, the only ones which
> look for power are the iPad (where the power is optional, but helps if
> you want to charge), and a pocket-sized hard drive.
I have two D-Link hubs, each of which has two ports which are stated to
be powered. The problem is that this feature apparently works only for
a PC and not for a Mac. There is an indicator on the hub which shows
green when the power is available and blue when it is not, and the two
hubs indicators remain blue. Apparently this is due to something lack
in the driver for the hub. I'm hopeful that someone has found out what
one can do to get the hubs to supply the power as was advertised when I
bought them.
--
James Leo Ryan - Austin, Texas
[commenting on obtaining USB power from a hub]
> Definitely a matter of not using el-cheapo. I have a (still quite
> inexpensive) D-link one which indicates that a couple of the USB ports
> are powered and others are not. And the powered ports work great with
> every device I've plugged in (though in fairness, the only ones which
> look for power are the iPad (where the power is optional, but helps if
> you want to charge), and a pocket-sized hard drive.
be powered. The problem is that this feature apparently works only for
a PC and not for a Mac. There is an indicator on the hub which shows
green when the power is available and blue when it is not, and the two
hubs indicators remain blue. Apparently this is due to something lack
in the driver for the hub. I'm hopeful that someone has found out what
one can do to get the hubs to supply the power as was advertised when I
bought them.
--
James Leo Ryan - Austin, Texas
eastwind
Apr 7, 2013, 9:41:07 PM4/7/13
to
Micro Center. If you have a Micro Center in your area, you're in luck.
These guys are great! He recommended a "QVS USB 2.0 High-Speed 13-port
Powered Hub." QVS is not a brand I'm familiar with, but he said they
make good product. Normally $50, the hub was on sale for half price.
Worth a try with their no-questions-asked return policy.
It works perfectly. Now I have enough ports for all my USB devices
without daisy-chaining hubs and the Seagate drive works flawlessly with
it—a major headache resolved. The refurbed Memorex is another story;
I've sent it back for a replacement, as it is now completely dead.
Thank you all for trying to help. Just wanted to share what I found
out. Maybe it'll help someone else.
eastwind
Apr 23, 2013, 10:30:19 PM4/23/13
to
replacement drive has arrived. I plugged it into two adjacent ports on
the 13-port QVS hub and it's worked perfectlly from that moment on. I'm
guessing that either the original unit was flawed when I bought it OR
with all the plugging and unplugging I subjected it to in order to get
it to work fried its little brain. Anyway, now that I've got both
problems solved, we return you to your previously scheduled program.
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