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USB Thumb drive on FEZ Mini


Hi, I’m new of micro framework.
I’m working around FEZ Mini but I’m no able to connect USB Thumb drive. When I insert the PenDrive to FEZ Mini is not fired the connect event.
The examples that I’ve found on the TinyCLR website don’t works. Where I’m wrong? How I can solve it? there any ready example?(I’ve tried the examples on but the USB Pendrive is not detected when is plugged in)
Can I use FEZ Mini with USB Thumb drive for storing data or I need of FEZ Domino?


FEZ Mini has USB device not USB host and so you can’t connect USB devices (you can’t connect USB thumb drive)! How did you connect the thumb drive to FEZ Mini?!?

See FAQ the question "What is the difference between FEZ Domino and FEZ Mini?"

You can use SD cards for storage if you like.


Sorry, but I’ve read the faq and the beginner guide ( also, and I want you to notice what at page 104 was written:

  1. USB Host
    There is almost always confusion between USB host and USB device. The USB host is the system that connects to multiple USB devices. For example, the PC is a USB host and it can connect to multiple USB devices like mice, keyboards and mass storage devices.
    Implementing a USB device is rather simple but implementing a host is far more complicated…

So, with faq+beginner guide I understand that the difference between FEZ Mini and FEZ Domino is that only Domino has USB host feature(connection to multiple USB devices). However, both support single USB device connection. So my answer is:
USB Thumb drive is not a USB device?
I must connect only this device to my FEZ Mini USB so I no need of host feature for multiple USB devices connection! Why I can’t use FEZ Mini for connect a single USB device like USB pendrive!?
Where I’m wrong!??!
Is there any clear explanation and sure response to this?!!?
Very thanks!


Did you pay close attention to what you just posted here? :slight_smile:
"There is almost always confusion between USB host and USB device."
Read that line one more time…you are still confusing USB host with USB device.
You do not understand the explanation. You can connect FEZ Mini to a PC USB port but you can’t connect a USB device to FEZ mini.

FEZ Domino has both USB ports…a USB host and USB device…FEZ Mini has USB device only …this means you can connect this USB device to a PC and not to another USB device (means you can’t connect a USB thumb drive!!)

I hope this explanation is more clear now.


FEZ Mini can be a thumb drive that can be connected to PC. But it can not play the role of PC and read thumb drive.


Chimpanzee, just trying to help out on making the documentation better for all (the real beginners, who don’t necessarily understand this).

The confusion here is “multiple”. That’s not technically correct, and confused Scippy. If the document didn’t state “multiple” then Scippy wouldn’t have said (paraphrased) “I only want to connect to ONE, why can’t I?”.

A USB Host is any “intelligent” controller that uses a “service” on the USB device. It doesn’t have to be able to handle “multiple” devices to be a USB Host. It’s all about being able to connect to the endpoints on the USB device, such as the mass storage service of a thumbdrive (over-the-top detail for this, but shows a lot more info on device classes and more). In this context, only Fez Domino can act as a USB host to connect a USB device to.


Funny that we know 9 out of 10 people out there do not know that there is a USB host and USB device and they do not know that a USB device can’t connect to another USB device…and USB host can’t connect to a USB host! This is why we started the description with “There is almost always confusion between USB host and USB device.”

I’m not sure how we can this clearer since we already knew about this and we tried to make it clear…so you think the word “multiple” is confusing users? Let us take a look and maybe make it sound better.
Thanks for the feedback Brett. :smiley:


OK, Now is clear for me!
Yes, I was confused by ‘multiple device’.
Another thing that made me confused is MP3Player hardware in the FEZMini hardware list (, about this is written:
…FEZ can read the MP3 files from the microSD card or from a thumb drive…
this is wrong, only FEZ Domino can read from thumb drive!
I think the better way to explain this is simply write on the FEZ Mini documentation:



The word “FEZ” covers both Mini and Domino. Stating “FEZ can read the MP3 files from the micro SD card or from a thumb drive” is a valid statement. However, I can see how the confusion occurs. We’ll definitely improve our wording and clear things up.


You’re right!
is precisely for this reason that I had thought that the “thumb drive” covered both Mini and Domino!


We have updated the description of FEZ Mini so there is no more confusion.