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GordWait's avatar
GordWait
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1 day ago

Cyclone VGT Dev Kit boards - some new boards failing to boot from NOR Flash

We've been using these boards for years, having certified them for use in one of our products. In the last few months we have now received 5 of these boards and they fail to configure from NOR flash...
Board Debug
Fpga Devkit
FakhrulA_altera's avatar
FakhrulA_altera
Icon for Regular Contributor rankRegular Contributor
12 hours ago

Hi,

Thanks for the detailed information and for outlining the debug steps taken.

From our side, there are known changes in the RevB board (including NOR flash device and routing), and there is a related knowledge base article that may be relevant to what you are seeing:

  • Why can’t I access the EPCQ flash device on the Cyclone V GT FPGA Development Kit (DK-DEV-5CGTD9N-B)?
    https://community.altera.com/kb/knowledge-base/why-cant-i-access-the-epcq-flash-device-on-the-cyclone®-v-gt-fpga-development-ki/344352

Before concluding this is the same root cause, could you help confirm a few points:

  1. Are all failing boards confirmed to be RevB, and using the same NOR flash device (Micron)?
  2. Does the issue persist even with the factory image without any modification?
  3. Are you able to consistently program and verify the NOR flash contents via JTAG on failing boards?
  4. Is the retry behavior reproducible across power cycles, or intermittent?

This will help us determine if your case aligns with the known issue or if something else is contributing.

Looking forward to your feedback.

Regards,
Fakhrul

GordWait's avatar
GordWait
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2 hours ago

Hi, thanks for your comments. 

Some answers
We don't use the EPCQ flash, just the NOR flash.
These are all Rev B with Micron Flash
Yes even the factory image is failing and retrying. On a good board the factory image boot is almost instant. On a bad board it takes seconds to "succeed" but sometimes fails. I ran tests with a modified bootloader and found that it is retrying dozens of times. 
Programming the NOR Flash via JTAG tools works with no errors, including the CRC readback tests, which verifies the data path from the flash to the MaxV pins is ok. 
The error is definitely repeatable across power cycles, and repeatable via pressing the config button. 

One new weird data point - if we load the factory binary maxv.pof image, (and have to switch the factory/user button to user) then 3 of the boards seem to boot ok with our image. The other 2 are still bad. 
I looked at the source, for some reason Altera inverted the factory_user switch signal in the v22 source code. 
BUT if I compile that same factory image from the V22 source, my version of it fails to work. I tried using the exact same Quartus edition - no better. 
All the compilations I make work fine on the good Rev B boards we have. Very mysterious.