USB Hub

[Olovskos]

Hello,
I`m working on a Midi Interface but I have Problems connecting the Atmega to a USB Hub. It is working perfectly without a Hub. But when I put a Hub between the Device and the PC it is not showing up.... I`ve tried 4 Hubs.

Is there something I have to take care of?

Thanks in advance

[blargg]

Hubs can be more picky about timing. Are you using a clock crystal for the Atmega?

[Olovskos]

Yes, I`m using a 16 Mhz Quarzoszillator (German notation, I don`t know the english ^^) like this http://upload.wikimedia.org/wikipedia/d ... llator.jpg

First I thought it is a Win 8.1 problem but the device doesn`t appear under Linux, too.

[blargg]

Oh, I wonder whether it's the level-shifting zener diodes etc. Hub might be more picky about that too. Have you tried a minimal USB program on the Atmega in case there's some bug in the Midi adapter code? I think there's one that acts like a phantom key press that wouldn't need any external hardware.

[Olovskos]

Yes I think it is something about my wiring...

I use a bi- directional level shifter and thats the problem maybe.

I tried some examples from the V-USB download and they all act like this. Today is holiday so I think I go and buy some diodes tomorrow and try again.

I will post the results here

[Olovskos]

UPDATE

Zener Diodes are working like a charm with hubs

[blargg]

Thanks for updating us. Interesting how you got away with it on the PC but not the hubs. Another piece of evidence of hubs being more picky, and one more reason for my personal avoidance of hubs.

[BobbyJackson]

Hello, Just new to this interface.

Please can someone tell me how can I buy the V USB PowerSwitch provides 8 bits of parallel output?

I am working on a project I in great need of this item

[blargg]

Go back to the topic list and click New Topic and ask the question there. This will keep is from being mixed with this one.