USB hubs do work!

[blackhawk]

I had read many times how people had added an USB hub to their computer to increase their communication speed. Honestly, I was a skeptic until last week. I had built my own indexer using an oriental motor and drive. Everything was working fine, but the motor just had a growl to it that I didn't like. After trying a few things with the drive, I talked to Shopbot and they suggested the USB hub. I bought about a $12 one from Newegg. My test speed went from 74% to 86%!!! The motor growl that I was hearing is gone, plus all my other motors run much smoother. If you don't have an USB hub, definitely get one.

I plugged mine into my main computer card and got these results. My hub also came with a power cord, but this made zero difference on the speed test.

[ted]

Hi Brad,

The reason that this works is: on many computers, putting a USB 2.0 Hub in the path to the ShopBot controller forces the path onto a "USB Enhanced" controller in the Windows low-level driver system rather than a "USB Universal Controller". The Enhanced controller provides better bandwith under most conditions.

You can usually see the effect of the switch in the Windows Device Manager if you view devices "By Connection" and expand them out to see the USB connections.

Ted Hall, ShopBot

[ken_rychlik]

Brad, if you post a link to the newegg item it would help those that don't have on already.

It is so cheap and does so much it's amazing how many run without it.

[frank134]

watch what hub you buy. frank from shopbot told me their are a fews that don't work well with shopbot controler like belkin, as I found out the hard way. I got a gigware which also stop all the com ports loses I was having. oh the one that come with the shop bot does not have good review too.

[blackhawk]

The one that I bought was Newegg item N82E16817111976 for $11.99 plus $2 shipping. It had the 5 "egg" rating, which is one of the reasons that I chose it. (The other reason is that I am sometimes cheap.:))

Here is a link:
http://www.newegg.com/Product/Product.aspx?Item=N82E16817111976&cm_re=usb_2.0_hub-_-17-111-976-_-Product

[ssflyer]

Another item to consider: I use an amplified (active) USB 2.0 extension cable, because my computer is away from the ShopBot, and I run the cable overhead. I also use a cheap USB 2.0 hub at the computer. This allows for long runs with excellent transmission rates.

Ron

[meatbal80]

I also have used the usb extension cord with a powered repeater and it increased my com by 10 or so %. Now i sit in the high 80's.

[jdervin]

My hub also came with a power cord, but this made zero difference on the speed test.

I'm using a D-Link Hi-Speed USB 2.0 Hub ($19.95 from B&H Photo) and found that running it without the power cord gave me a 5-10% speed test improvement. Unfortunately, I'm still in the low-to-mid 60's.

[bleeth]

John:
Those results are lower than they should be. Do you have at least 2MB RAM? Are you plugged into a USB2 port in your computer or do you have a seperate card? Some have had issues when it is a built in port. Is your convertor also able to handle higher speed and is the software for it properly loaded?
The only other option would be that the processing speed of your computer itself is too low. That would likely be true only if you were using a really oldie but still goodie!

Dave

[ssflyer]

John,

Another thing to check - on many computers, I've found that the front connectors (if so equipped) seem to function as 1.0 ports, instead of 2.0. So, if you are using a front USB port, you might want to try a port in back, connected directly to the motherboard. Also, check in device manager and see if it's listed as an Enhanced Host controller. Also make sure you don't have any old legacy USB 1.0 devices hooked up to the same controller.

Ron

[curtiss]

So what is the process for checking the speed of the USB connection ?

[Brady Watson]

C:\Program Files\ShopBot\Diagnostics\SpeedTest.exe

[ssflyer]

As Brady stated, that is where you find the speed test to the 'Bot, but there us also another program - C:\Program Files\ShopBot\Diagnostics\usbview.exe that will show you perhaps more information than device manager. If you use it (with the 'Bot running) you should see "Shopbot" listed under one of the controllers. If you click it, you will see a window on the right that lists the working parameters of the connection. One of the parameters is "Device Bus Speed." This should be "High." If it is not, make sure there are no legacy devices (USB 1.0) connected to the same controller, like your mouse. The controller should also be listed as an Enhanced Host Controller - preferably not a "Universal" or "Generic." If nothing else is connected to the controller, and you still see it as Low Speed, the either change where it is plugged in, or, worst case (as in your computer has no USB 2.0 ports), then you can buy a cheap card that plugs into your motherboard that will provide 2.0 speeds.

Hope this helps,
Ron

[jdervin]

Thanks all, for the tips and ideas. I just got home from checking things following Dave's post, only to discover all these great additional posts. I'll have to look into everything in more detail as soon as possible.

FYI: my RAM is 3.21Mb, processor is 3.32GHz, and I am plugging into the back of the computer (not a card, but through a hub) -- though I still need to make sure erverything's running at 2.0 speeds.

For the fun of it, I ran a series of speed tests in three different configurations (four times each):
1.) direct plug/no hub
2.) hub without power
3.) hub with power
...and this time, unlike previous tests, I averaged roughly 68% across the board. Go figure. The range was between 66.5 and 69.2. Certainly better results than I've had in the recent past, but I would really love to get over 70% (especially 'cause in addition to dropped comm's, I also experience intermittent problems with spindle speed control).

Not sure why, but twice during testing, the process froze on the 999th returned packet.

Of course, while this is all seemingly contradictory to the original thread topic, I still maintain that I too have seen marked improvement with the use of a USB hub.

[ken_rychlik]

Ram is cheap and you should bump it up to at least one gig

[jdervin]

Ram is cheap...

...and typos are even cheaper (at least in this case). What I should have said is that my RAM is 3.21 Gb. Oops.

[curtiss]

Bill Gates once said,

"No one will ever need more than 8MB of RAM...."

I don't think he has a bot.

[Gary Campbell]

John...
Any chance your computer brand is a Dell?

[plemon]

I noticed people have mentioned that the belkin usb hub is no good. Has anyone ever used the Targus Desktop 7-Port USB 2.0 Hub? It is a powered one and got the best reviews over multiple sites.

[jdervin]

Gary--

Yes indeed. Dell it is. I can't remember which model, and I'm not near the machine. However, I've also used a Dell Lattitude E6400 laptop to run the 'Bot and never have any problems (speed test in the mid-70's if memory serves), but I'm curious to know if there's a possible 'Bot related issue with Dell computers.

[adrianm]

I use the hub that ShopBot supplied with my Alpha and it boosts the signal from 68% to 79%.

[jim_rutske]

Great thread guys, I have learned a lot. I have a Belkin USB2 5 port card installed. The bot is the only item plugged in to that card. When I run the speed test it is 73% as it has always been. Yes, I have had lost comm issues and my motors growl like a cat in heat.
When I look at the USB view it has the bot listed as Full speed but not High speed. This is a big difference in the USB world. I have confirmed that I have the latest drivers installed. Is there something I'm missing that can switch this over to a High speed connection and get my transfer rate up? Is Belkin just a bad choice of cards?

[Gary Campbell]

John...
If you do a search for USB problems, Brady has listed in detail the problems with the Dell architecture. Try putting in an inexpensive USB 2.0 pci card and see what the comm rate is.

[jdervin]

Gary--

Thanks for pointing me in this direction. For interested others, here are three valuable links I turned up:

http://www.talkshopbot.com/forum/showpost.php?p=22799&postcount=8

http://www.talkshopbot.com/forum/showpost.php?p=25944&postcount=6

http://www.talkshopbot.com/forum/showpost.php?p=90548&postcount=5

[ATX Poly Products]

I just went with a Staples 4 port 2.0 powered hub and it took mine from 56% up to 78%...

But my x axis moters still have a growl in the speed range between .8-1.4 IPS

Anything below or above those speeds and they are real quiet and smooth. It doesn't seem to affect the cut quaility but it does sound awful. Especially when I run a cut in air without the PC head drowning the growl out... Is there anything I can do about this?

Adam

[Brady Watson]

...But my x axis moters still have a growl in the speed range between .8-1.4 IPS

Anything below or above those speeds and they are real quiet and smooth. It doesn't seem to affect the cut quaility but it does sound awful. Especially when I run a cut in air without the PC head drowning the growl out... Is there anything I can do about this?


Adam,
All stepper motors show some low and mid-band resonance at certain speeds. I'm going to guess that you have a newer PRS Standard with RBK (aluminum control box) - The noise you hear is normal for your system - although I fully agree it is awfully annoying at certain speeds.

Older PRS Standard tools that used the 4G control board and Gecko stepper drives, sounded much smoother at those speeds than the new RBK driver models. However, the RBK tools have more torque than the 4G models and that translates into more usable power for cutting.

-B

[ssflyer]

Is this also normal for a PRSAlpha? Mine runs smoothly at any speed I've tried. However, the cuts are obviously different at different speeds/feeds...

[Brady Watson]

Ron,
Yes & No. The Alpha is unique in that it has a pretty sophisticated driver system, which includes resonance and velocity filtering to prevent the majority of that resonance.

Your 7.2:1 geared Alpha will show very little resonance. However, a 1:1 Alpha motor, found on 3G PRTs, has all kinds of resonance at lower speeds.

-B

[ATX Poly Products]

Adam,
All stepper motors show some low and mid-band resonance at certain speeds. I'm going to guess that you have a newer PRS Standard with RBK (aluminum control box) - The noise you hear is normal for your system - although I fully agree it is awfully annoying at certain speeds.

Older PRS Standard tools that used the 4G control board and Gecko stepper drives, sounded much smoother at those speeds than the new RBK driver models. However, the RBK tools have more torque than the 4G models and that translates into more usable power for cutting.

-B

Thanks Alot Brady...

Yes that is the system I have. With the PC head running and me wearing Muffs It isn't noticeable really..