Interrupts

General discussions about V-USB, our firmware-only implementation of a low speed USB device on Atmel's AVR microcontrollers
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samlii
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Interrupts

Post by samlii » Wed Sep 12, 2007 6:48 am

I was wondering if there was a technical reason for only using interrupt0? For a design I am thinking about I was going to put it at interrupt2.

Interrupt2 on the 8515 (my target chip) is an edge interrupt only, will this mess up the interrupts USB is trying to take advantage of?

vobs
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Re: Interrupts

Post by vobs » Wed Sep 12, 2007 11:56 am

The code will work with Int2 (I've done that with an Mega162).
But beware: Int0 and Int1 have a higher priority than Int2. This might cause some problems, when using these Interrups.

Are you sure that the 8515 has an Int2? Or do you mean the Mega 8515?

christian
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Objective Development
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Post by christian » Wed Sep 12, 2007 6:26 pm

Please also note that you need the most recent version (2007-08-07) of AVR-USB. Older versions had the interrupt vector hardcoded in the assembler modules.

butrus.butrus
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Post by butrus.butrus » Wed Sep 12, 2007 8:59 pm

christian wrote:Please also note that you need the most recent version (2007-08-07) of AVR-USB. Older versions had the interrupt vector hardcoded in the assembler modules.


Is that the one, that comes with the latest AVR-Dopper? BTW, wouldn't it be possible to have releases just for AVR-USB (or even better to use SVN or simillar system)?

Thanks!

christian
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Post by christian » Wed Sep 12, 2007 9:05 pm

Yes, AVR-Doper ships with the latest library (as the version indicates).

If you want just AVR-USB, please download PowerSwitch. We prefer to ship a working example because that saves a lot of questions about how the library should be used.

samlii
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Post by samlii » Thu Sep 13, 2007 4:16 am

Oh I see it now in the new version ;) Seems to make sense, thanks guys for thinking of us all.

Yes it is a mega8515, sorry about any confusion.

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