CMOD A7 Doesn't Work with FSBL Example

[RichardV]

Hello, I am trying to follow this example: "How To Store Your SDK Project in SPI Flash", found on this website (https://reference.digilentinc.com/learn/programmable-logic/tutorials/htsspisf/start). I am also following the "Getting Started" example (found at: https://reference.digilentinc.com/learn/programmable-logic/tutorials/cmod-a7-getting-started-with-microblaze/start ) to create a "Hello World" example.

I've gone through this example several times now and I cannot get it to work. The devices programs per the instructions without errors, but my code does not run. Attached is my block diagram. I couldn't find an example showing how to connect the AXI QSPI block, but the Validation shows no errors.

Step 2.3) is confusing. There is nothing to explain what that "mig_7series_0" is. I also attached an image of what my "Generate linker script" page looks like. I made one of the settings different to show the alternate choice available. I don't know which one to use. The CMOD A7 does not have "DDR" memory, so I don't know what to do here.

Can anyone help me spot what I am doing wrong here?

Which memory option should I use:

microblaze_0_local_memory_ilmb_bram_if_cntlr_microblaze_0_local_memory_dlmb_bram_if_cntlr

or

axi_emc_0_S_AXI_MEM0_BASEADDR

?

Thank you, Richard V

[jpeyron]

Hi @RichardV,

In the How to Store your SDK project in flash tutorial here the note on 1.3) should have said "If you are using the Cmod-A7 and you have not compressed your bitstream try the offset: 0x00300000." i have fixed this on the tutorial. Here is a forum thread that should be useful as well. When you set up the Microblaze the local memory should be 32k and the cache at 16k. I have just completed the tutorial with no issues and have attached my project. I did it in Vivado 2017.1 in case there was a version issue.

cheers,

Jon

cmodA7_flash_issue.zip

[RichardV]

Hello Jon. Thank you for your response. Unfortunately I was unable to open your file. I'm using version 2016.2, and the one you used is newer. I could not look at your block diagram. I followed your advice and got it to work. The biggest mistake I made: Cache was 8Kb. You recommended 16Kb and this makes all the difference. When using 8Kb, my data baud rate and format were bad.

Just a note that isn't clear in step 2.3. I chose the option "axi_emc_0_S_AXI_MEM0_BASEADDR" and this works. Any other option and one will get nothing on the UART (non-operational).

You mentioned that you made a correction regarding the offset value if "not using" compression. I used that value shown for the CMod-A7 (0x00300000) and it worked just fine. What other values should we use? I presume it depends on the size of "download.bit". Please offer your thoughts.

Thank you for your help.

Sincerely, Richard V

 

[jpeyron]

Hi @RichardV,

I am glad you are able to get it working. Thank you for the feed back on the tutorial. I haven't tried using the compressed bitstream so I do not have any suggestions for the offset.

cheer,

Jon