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USB superspeed peripherals Forum Discussions

Anonymous
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Hi, we designed and assembled two prototyping board mounting a ES of the EZ-FX3. The board plugs directly into a Xilinx virtex6 development board trough an FMC connector.

   

The “thing” is now working well end delivers 220 MB/s using the modified BulkSource reference firmware posted by aasi on this forum.

   

On our original board design we simple connected the 32 kHz Watchdog Timer Clock Input to ground as one would do if there is no interest  on using the watchdog functionality (also considering that in the datasheet the 32 kHz clock is referred as optional). Using this approach unfortunately the USB bus do not works. The CPU boots correctly and tries to load the firmware from the I2C (if configured so) but the load from USB simply doesn’t work since the USB interface doesn’t work.

   

Well, we mounted a second prototyping board but this was affected from the same problem. In the end, in order to make our system as much similar as the Cypress development board we connected the Watchdog Timer Clock input to a 32KHz clock source … and  … miracle … The USB 3 interface works perfectly, with the above mentioned performances.

   

My question: why is there no mention about this important detail in the FX3 datasheet ? Do we missed something ? Did somebody ever tried to use an USB 3.0 FX3 without the 32 KHz clock ?

   

Joel

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Anonymous
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Hi Joel,

   

If the 32 KHz clock is not present in the system, the USB block stays in reset and hence USB boot does not work. This issue is being corrected in the next rev of silicon. For now, please hook up a 32 KHz clock to FX3.

In the new rev the boot loader will have the option of switching to an internal 32 KHz clock after detecting the absence of an external 32 KHz clock.

   

Regards,

   

Anand

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Anonymous
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Thanks,

   

is there any other issue that a user should know in order to avoid wasting time investigating  on already known issues of the ES version of FX3?

   

 

   

.

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Anonymous
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        Hi aasi, When will you release its next rev of silicon? > In the new rev the boot loader will have the option ... In FX3 SDK beta-3, does it include its new rev the boot loader? Can the new rev boot loader work without external 32KHz clock? Regards, KAMADA Keisuke > If the 32 KHz clock is not present in the system, the USB block stays in reset and hence USB boot does not work. This issue is being corrected in the next rev of silicon. For now, please hook up a 32 KHz clock to FX3. > > In the new rev the boot loader will have the option of switching to an internal 32 KHz clock after detecting the absence of an external 32 KHz clock.   
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Anonymous
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We have run into the same issue; we did not hook up the 32 kHz clock and thus USB does not come out of reset.

   

We have confirmed that I2C is working, however.  If we load an entire firmware image over I2C, is it possible to pull the USB subsystem out of reset using firmware?  Which API in particular?

   

Thanks!

   

    

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Anonymous
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As cypress employees written in several topics, this i not possible in the current silicon revision of the FX3. You have to hook up the clock or wait for new chip revision.

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Anonymous
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Thanks, Chris.  Could you provide a link to the topics where that was made clear?  I have not found any topics on this issue other than this one and http://www.cypress.com/?app=forum&id=167&rID=53755

   

In this topic at least, aasi only said that USB boot was not possible with the current silicon without the 32kHz clock, and nothing about the ability of I2C-loaded firmware to pull the USB subsystem out of reset.

   

Thanks!

   

    

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Anonymous
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Hmmm...I was sure, aasi wrote this several times. But I also cannot find the other topic(s). You´re right, may be it works with pre-programmed I2C EEPROM booting, but I´m not sure. I think only aasi can answer this....

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Anonymous
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Hi,

   

We did remove the dependency of 32kHz external clock input in the firmware in Beta2 and 3. So any of the SDK firmware in Beta2 or 3 should be able to bring the USB block up through I2C boot load.

   

Beta1 has this dependency and won't work even through I2C bootload.

   

Cheers,

   

Anand

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Anonymous
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Thanks; that is precisely what we were hoping to hear!

   

The workaround brings up a few more questions, but I'll make new threads for them.

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Anonymous
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Hello joebreprivate,

   

is it possible to buy such a FMC daughter card from your company? I am working at a Fraunhofer Institute in Germany and we plan to use the FX3 is a new device, but want to test all the things before with the Xilinx FPGA boards....

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