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Writing to HPS Memory tutorial
Added by Travis Rawson almost 4 years ago
Hello,
So I am working on getting data to be passed from the FPGA to the HPS. I started following the "Writing to HPS Memory" tutorial, but got stuck on compiling the FPGA image. Once I re-built that and had it successfully compile/burned to the FPGA I tried to run the "memtool" commands. When I get to the "memtool -32 0x30000000 32" command, it fails and I get this error:
**
root@mitysom-c5:~/New folder# memtool -32 0x30000000 32
Reading 0x32 count starting at address 0x30000000Unhandled fault: external abort on non-linefetch (0x1018) at 0x76fc8 000
pgd = 9ef50000
[76fc8000] *pgd=1ecf1831, *pte=30000703, *ppte=30000e33
Bus error
**
I know the FPGA is burned correctly, since I changed the Sysid number and saw the change in the respective memory location.
Am I missing a step here? On a side note, I am not too experienced with this portion of stuff. I am more of a FPGA developer. If you know of a good place with resources to understand what is going on, that would be tremendously helpful, or if you know how to do this kind of stuff with Python. Any help would be appreciated!
Thanks!
Replies (2)
RE: Writing to HPS Memory tutorial - Added by Daniel Vincelette almost 4 years ago
Hello Travis,
Are you are using a MitySOM-5CSE-L2-3Y8 Module, which has 512MB of RAM instead of 1GB? This example is set up to work with the 1GB of ram and a few of the addresses will need to be changed to work with the 5CSE-L2-3Y8.
For integrating with python this isn't something that I've done before, though it might be doable with a module that allows for direct memory reads/writes.
For integration with the HPS subsystem I go to the following document a lot: https://www.intel.com/content/dam/www/programmable/us/en/pdfs/literature/hb/cyclone-v/cv_54008.pdf.The following sections talk about the main interfaces used to communicate between the FPGA and ARM:
- Section 9: HPS-FPGA Bridges
- Section 12-5: FPGA-to-HPS SDRAM Interface
Dan
RE: Writing to HPS Memory tutorial - Added by Travis Rawson almost 4 years ago
Hey Dan,
That was the problem. All fixed and working now. Thank you for the help!
Travis