Advice Needed Re USB Ports

[Tamtarn]

Hi Guys

We need some advice re adding USB Ports.

Our laptop has only one USB1 Port and we need to increase the number of Ports for future use.

There seems to be two options available.

A Powered 4-7 Port USB2 Hub.or - a 4 Port USB2 PCMCIA Card Bus 32/16 Bit.
We have a slot available for the PCMCIA Card.

One of the ports will be used for a DSI Pro. which I believe is a little bit power hungry.

Will a PCMCIA Card give me full USB2 power ? compared to the Powered USB2 Hub which will be connected to the present USB1 Port.

Any advice most welcome.

David

[DeanoNZL (Adrian)]

Hi Barb and David.
You will need them both.
The PCMCIA card is needed to enable your laptop to receive USB2.
(Unless you can find a PCMCIA card with external power)
And...
The powered hub to be able to run the DSI.

The Hub alone will not work, as you have USB1.
CS

[Astroman (Andrew Wall)]

I agree with the above statements, you will need a USB2 PCMCIA card first then a POWERED hub.

[Dennis]

Hi Dave & Barb

Whenever I have needed to expand the ports on my 4 ½ year old IBM ThinkPad R40 (USB2), I have consistently found that the most reliable way is via the PCMCIA card. When I tried only an external USB powered hub connected to the native USB port, I sometimes experienced problems with certain imaging devices.

So, it might be worth just getting the powered PCMCIA card as phase 1 and seeing if that meets your needs and if it does, then end of story. If not, then add the external powered hub?

Cheers

Dennis

[[1ponders] (Paul)]

Agreed as above. I had a PCMCIA Card that had a plug for an AC adapter and while it worked with some things it didn't work with others. Ended up getting a powered hub to go with it.

[Tamtarn]

Adrian : Andrew : Dennis : Paul.

Thanks for the great advice guys. really appreciate your help.

Will purchase both the PCMCIA Card and Powered Hub.

Getting set up for auto guiding, now have guide scope and GPUSB adapter,
just have to wait for DSI Pro to arrive.

Looking forward to better images with guiding.

Thanks again

David

[peter_4059 (Peter)]

I have a question related to this thread...

If you have a computer that has three USB2 ports (standard not hub/pcmcia etc) in it and you attach a USB2 device to one and a USB1 device to another do you still get USB 2 bandwith for the port that has the USB2 device or does the whole thing slow down to USB 1 speed?

[[1ponders] (Paul)]

My understanding is that each USB port should operate independently to each other so the USB 1 device should only affect that port. In fact if you add a USB 2 powered hub to the port you can still use it as a usb 2 port, the USB 1 device will be the only one operating at USB1 speeds.

That's is my understanding anyway

[peter_4059 (Peter)]

Thanks Paul,

Do you know if there is any way to test this? Can you tell from the windows device manager in any way?

Peter

[[1ponders] (Paul)]

I'm not sure how you can do this through Device Manager, though if you check each USB root hub instance you will be able to see how much power is available per port and if you check the properties of each instance of the host controller you can see how much bandwidth is allocated to each port. If you plug in your usb 1 device you can then do a comparison of with/without. That may give you some idea as to what is happening.

If netwolf pops in or one of the other techi - gurus they will be able to enlighten you more accurately. I'm a bit of a neanderthal in this area.

[peter_4059 (Peter)]

thanks - I'll give that a try. I'm accumulating astronomy related USB devices and will soon have enough cables to strangle a pony!

[Zuts]

Hi,

One way to test this is with a bandwidth test. Download Sisoft Sandra, its a free PC benchmarking program. Then if you have a USB key plug it in and benchmark read write speeds with the USB 1.1 device also plugged in. USB 1.1 is 12 megabits per sec max, so if you get around this or higher then definately you are running at USB 2.0 speeds.

Paul

[peter_4059 (Peter)]

Paul,

This seems like a really easy way to check out what going on.

Thanks for the advice,

Peter