Using more than two USB devices

R

rptb1

Member
I need to use more than two USB devices with Parallels.

I'm running 3106 beta 3 with a Boot Camp partition. The help says: "The current version of Parallels Desktop emulates the 2-port USB 2.0 controller and 8-ports USB 1.1 controller. This means that up to two 2.0 USB peripherals can be connected to a virtual machine simultaneously."

Is it possible to extend the limit on the number of devices? I'm working with some development hardware that requires me to connect three devices, and I'd really like to be able to use Parallels to do it. I'm sure there are quite a few people out there with USB hubs with half a dozen devices on them that they'd like access to.

Why is the limit so low? Why not emulate a controller with more ports? Is there any plan to extend?
 
I've been asking for this since day one. I have no idea why more devices aren't available, and I wish they were.
 
rptb1 said:
I need to use more than two USB devices with Parallels.

I'm running 3106 beta 3 with a Boot Camp partition. The help says: "The current version of Parallels Desktop emulates the 2-port USB 2.0 controller and 8-ports USB 1.1 controller. This means that up to two 2.0 USB peripherals can be connected to a virtual machine simultaneously."

Is it possible to extend the limit on the number of devices? I'm working with some development hardware that requires me to connect three devices, and I'd really like to be able to use Parallels to do it. I'm sure there are quite a few people out there with USB hubs with half a dozen devices on them that they'd like access to.

Why is the limit so low? Why not emulate a controller with more ports? Is there any plan to extend?
Click to expand...

Have you tried using a hub that would extend the use of a single USB port to a larger number?
 
I am using a hub, but the hub is recognized by the Mac and each device appears separately as far as Parallels Desktop is concerned, so it doesn't help. Parallels would have to emulate a hub being attached, I suppose. They might as well extend the emulated controller.

I'd still like to know if there's a plan to extend. This is critical to my using Parallels rather than Boot Camp.
 
Thanks for that, but it seems to be just for printers, and it turns them into network devices. The device(s) I have to connect are not printers, and they must remain as USB devices as far as the emulated PC is concerned. I'm afraid I'm not allowed to go in to details about the hardware.
 
Well I have to say I'm disappointed by the complete lack of response to my question and I'm disinclined to buy Parallels, since I have no idea whether it will ever meet my needs.
 
Have you tried attaching more than 2 deivces in 3150?
If it didn't work, can you please specify them?
 
ANYONE that expects FULL windows environment from a virtualization program IMHO is non-realistic.

If the full windows environment is required, you need to use Boot-Camp or better yet, buy a PC.

There are just too many variables to expect everyhting to work!

For 80 - 90percent of those Mac users who need an occasional windows program Parallels is already sufficient and adequate.

BTW - This is a USER forum. Support should not be expected from the Parallels team. If there are problems OR feedback, that should be sent to beta@parallels.com I also might ask how many responses have you received from the Apple Forums from Apple design team? Personally, I want them working on the program and improving it rather then wating time answering 10s of thousands questions.

ajm
 
rptb1 said:
Thanks for that, but it seems to be just for printers, and it turns them into network devices. The device(s) I have to connect are not printers, and they must remain as USB devices as far as the emulated PC is concerned. I'm afraid I'm not allowed to go in to details about the hardware.
Click to expand...

I can read a data stream from an external sensor unit via a KeySpan 19HS USB-serial converter. In 3150 the process works fairly well. I'm still hoping for further refinement by the time of the actual release of Parallels but it is working now in predictable ways unlike the prior incarnations.

Remaining problems:
Recognition of the device is intermittent and can fail, requiring the device to be unplugged, replugged and redetected by the guest OS.
Setting the data rate to the highest level possible will bring down the driver. I have to let it choose the connection speed (done using the KeySpan Assistant software).
The overall process requires too much system resource and takes just too long for it to be a deployable solution at this time but it is very, very close -- and I'd be happy to dialogue with Parallels directly about this so that I could use Parallels instead of Boot Camp for my deployed systems.
 
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Many thanks for getting back to me ksenks.

Have you tried attaching more than 2 deivces in 3150?
Click to expand...

I'm now running 3170. If I try to connect more than two devices a sheet pops up saying that "All USB ports are currently being used." The development hardware that I'm using has three USB connections and a serial connection, so I have all three USBs and a KeySpan USB to serial connection plugged into a Belkin hub which is then connected to my desktop iMac. I'm afraid I'm not allowed to reveal the exact nature of the development hardware.

Using Apple System Profiler I can see that this is a USB 1 hub. Does this mean that the devices will only connect to the virtual USB 1 controller, and therefore there is still a limit of two devices?

I tried an experiment: I plugged one of the three USB connections direct to the iMac and can now connect all three, but not the KeySpan (I'm out of ports). So my theory is probably right: USB 2 devices need to be on a USB 2 hub to get round the two device limit.

If this is indeed the restriction then perhaps the error messages need to be a bit clearer, and the USB 1 and USB 2 devices separated (or indicated) in the user interface.

So the next step is to buy a USB 2 hub and try that. I'll report back.
 
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ANYONE that expects FULL windows environment from a virtualization program IMHO is non-realistic.
Click to expand...

Indeed they are. But requesting an answer about intentions for Parallels is reasonable, I think.

If there are problems OR feedback, that should be sent to beta@parallels.com
Click to expand...

Tried that. My next step was to try the phone.

Personally, I want them working on the program and improving it rather then wating time answering 10s of thousands questions.
Click to expand...

I have to make a commercial purchasing decision based on the information I have available. It's up to Parallels to decide how much time to invest in providing information and channels to get it, but their responsiveness is relevant to my decision.

May I suggest you uncock your flamethrower?
 
rptb1 said:
So the next step is to buy a USB 2 hub and try that. I'll report back.
Click to expand...

Success! I got hold of a four port USB 2 hub and connected the three development kit USB devices and a Keyspan serial-to-USB to it, and plugged that into the Mac. Parallels was able to attach all four USB devices to the Windows VM and I was able to work with the development kit just fine. FWIW, the hub was an "i-rocks Crystal IR-4300 USB 2.0 4 port hub", but I'm sure any similar device would do the trick.

So my main comment to Parallels is that the user interface now needs improving to make it clear that USB 1 and USB 2 devices are treated differently.

We're now considering buying iMacs and Parallels for development rather than PCs.
 
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