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Altera_Forum's avatar
Altera_Forum
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21 years ago

Verifying EPCS images

QII4.1SP1

I have both an EPCS header and a Jtag header which allows me to use sof, pof or jic.

The sof and pof files are default outputs of Quartus.

The jic file is produced from the default sof by using the Quartus file convert utility.

I noticed that when I programmed the EPCS1SI8 device with the jic over Jtag, it would fail to verify against the pof using the direct EPCS header.

I did find that if I also used the file convert utility to produce a second pof file from the default sof, this pof would verify OK against the jic image.

So it appears that the pof image produced by a Quartus compile does not match images produced by the Quartus file convert utility.

The files are all roughly the same size. I would expect differences in the files themselves but not the images they produce.

Is this a bug? Does the difference produce a different FPGA configuration?

Is there an existing tool that will let me examine the contents of the EPCS device?

The examine box in the Quartus programmer does not seem to do anything.

thanks

2 Replies

  • Altera_Forum's avatar
    Altera_Forum
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    21 years ago

    I believe you can examine the contents of EPCS; you may have to play around a bit. The idea is to do an "examine" and then File --> Save as (although I'm probably not 100% correct on this -- I'd imagine there is some Quartus literature that explains it).

    One other thing that comes to mind (but not explained by the similar sizes you report): In the quartus covnert programming files tool you can optionally turn on/off FPGA bitstream compression when creating your JIC file. I believe you have to select the FPGA-configuration and then hit the properties button to display this dialog. This would indeed change the configuration data significantly.
  • Altera_Forum's avatar
    Altera_Forum
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    21 years ago

    Remember that I am comparing the resulting images, not the files. It could be there are still elements of this image that are not actual configuration data.

    The only compression option I see in the file converter seems to be to indicate if the input SOF is compressed, not the output.

    My pof and jic files are around 128KB. This seems to correspond to the 128KB size of the EPCS1 device, and so would suggest an uncompressed format, but I know my project settings have compressed bitstreams on.

    I did do an examine and save file in the Quartus programmer, but it seems I can only get another pof of questionable format. A raw binary is the only thing that would makes sense to compare. Even that wont tell me if the image differences I see are for legitimate reasons such as an embedded timestamp, or are a bug. I would need an explanation of the POF format - need those docs.