Winusb - multi device multi application   

Hi,
I am going through documentation available on Winusb and it says that
Winusb shoud be used  when "the device is accessed by only a single
application".

My question is

1) if i use multiple instances of same application to communicate with
different intances of same device(i.e. many boards of same kind
connect to PC via hub) , can i use winusb.

2) if my application communicates with different intances of same
device(i.e. many boards of same kind connect to PC via hub) .
Communication with each instance happens in separate thread. Can i use
WinUsb.

3) Can i use WinUSB in both case

Thanks for an answer

-Anshul

date: Sat, 26 Jan 2008 01:03:39 -0800 (PST)   author:   xxx

Re: Winusb - multi device multi application   

My short and direct answer for all three questions is, you'll most likely
have to try it out to be sure.  My best guess and individual answer to your
questions is 1. Yes, 2. Yes, 3. Yes.

Here's the explanation.

From what you told me, USB is the technology and who-knows-what is the
protocol.  With most common protocols that use USB, there will need to be an
exclusive connection from a specific application to a specific external
device.  Given the instruction, "the device is accessed by only a single
application", WinUSB not only uses one of the protocols with that
requirement, but also cannot handle multiple connections to the same
external device.

There will be distinction between multiple instances of the application
(assuming it is thread-safe) and multiple instances of the same external
device.  Therefore, an array (multiple similar applications or devices) on
either end should pose no problem, so long as no application attempts to
make a connection to a device that already has one.


David L. Burkhart
Burkhart Technology Services
http://www.BurkhartTech.com


"xxx"  wrote in message 
news:181d9574-48b4-40dc-be38-fc479291eb04@d21g2000prf.googlegroups.com...
> Hi,
> I am going through documentation available on Winusb and it says that
> Winusb shoud be used  when "the device is accessed by only a single
> application".
>
> My question is
>
> 1) if i use multiple instances of same application to communicate with
> different intances of same device(i.e. many boards of same kind
> connect to PC via hub) , can i use winusb.
>
> 2) if my application communicates with different intances of same
> device(i.e. many boards of same kind connect to PC via hub) .
> Communication with each instance happens in separate thread. Can i use
> WinUsb.
>
> 3) Can i use WinUSB in both case
>
> Thanks for an answer
>
> -Anshul
>

date: Sat, 26 Jan 2008 15:59:56 -0500   author:   David L. Burkhart