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Usb cdc



Regarding the USB CDC interface:

I know that simultaneous Debugging and CDC communications was revoked due to support issues however I feel perhaps this could be revisited for a select few :slight_smile: I think that it’s better to have everything done over the USB in this way so that you won’t need to buy an additional com port shield that consumes one of the 4 ports; nor would you need to buy a usb to serial cable to connect your laptop to it.

I’m just asking, not complaining; please don’t beat me up for this.


Hi kurt ,

I think it is not possible (or very hard to implement) this feature. USB CDC is GHI stuff and debugging is MS stuff.

In my opinion it is easier to add a small USB2Serial port for debugging. Or when you use FEZ Cobra you can debug over Ethernet.


The problem here is actually windows! We had this perfectly working but a user can make a little mistake which will then causes windows to put something in registry and after that you can never use FEZ again! The only way to to format your your PC or maybe try a restore point.

The risk involved outcomes the benefit by many folds. I haven’t even started talking about the huge load of support that came with it. So, we simply do not support that now and we won’t in future :slight_smile:

Of course, if someone needed this professionally and is willing to pay a lot of money then we can figure it out…you better have pockets full of money :smiley:


In my mind I like having them separated as it provides a physical and logical separation to the two different functions. It is somewhat of a pain to need to have two cables hooked up but when I do work on a uC that requires the use of a JTAG or or ICE then there is more than one cable too.

Using one of the USB2SER or PropPlugs that Parallax makes is an easy and inexpensive way to use a USB port for serial debugging.


Ah, I see. Windows installed the Fez as a Device and updated the registry accordingly. Then it prob forgot that the Fez was on that bus in the first place!

Won’t you need a simple registry edit to remove that though? One could even write a tool.

Exactly how many zeros deep would those pockets have to be?


Or just do it right the first time and you never have to worry about it. Anyway, this discussion is not going anywhere since GHI doesn’t support that and will not support it. After all, when you ship your product, you will probably do not want a debugging interface on it :slight_smile: And if you are only doing this for fun then it is 1000 times better to not use dual interfaces…

I really do not want to explain this anymore :slight_smile: We had tried it and it was too much work for little benefit and it was dropped. GHI wouldn’t drop a feature that took us weeks to implement if we didn’t have good reasons to do so :wink:


Ok sounds fair.


I just relized something: The CDC device is only supported on the Framework 4.1? I’ve been trying to confirm but I don’t have an old version of the tutorial.


USB client is something that was only very recently added. I think it was the 4.1 FEZ release.


Rats, Ok then


You should be upgrading to 4.1 anyway, even if you do not need the new features!


Yea, I’ll be upgrading but I’m out of space on the net book so I have to remove VS2008 first :frowning:

That’s gonna be a pain.


Not as much as you might think. I uninstalled VS2008 Pro before I upgraded to 2010. It wasn’t too bad. :wink:


VS2010 works way better then 2008 :slight_smile:


Yea VS2010 is better, I just ran out of space.

Well it’s installed now. Next step is to upgrade the Fez, Yatta.


Make sure you uninstall ALL the NETMF stuff before you install anything more. I have had weird issues in the past coming from old installations.


Yep I think I stripped everything off. Installing the new framework now.


The Led flashes. Total upgrade is successful

In case anyone is wondering, I use Visual Studio Ultimate (with Team Foundation Server version control support)