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Rodo's avatar
Rodo
Icon for Occasional Contributor rankOccasional Contributor
4 years ago

Can I run a MAX10 from external RAM instead of on-chip RAM?

Hi all,

This is for MAX10 (10M08), nios II, quartus lite v20.1.1

I can make a design in platform designer with a nios II, on-chip RAM, a few PIO and no flash, save it and use the programmer in quartus to program the sof file. Then, in eclipse I make an application that will toggle some of the PIO pins and use Run as...nios II hardware to program the software. This all works. I know I'm not programming the MAX10 flash. I don't have a flash IP in my design and when I disconnect/re-connect the power I have to program the sof file and application again. This is fine because I'm making changes as I work.

I'm running out of on-chip RAM. Is there a way to use external RAM to do this? I would like use "Run as...nios II hardware" to program the software/application as I'm making several changes. I'm aware of AN730 but I don't see option 3 with external RAM.

Thanks

2 Replies

  • sstrell's avatar
    sstrell
    Icon for Super Contributor rankSuper Contributor
    4 years ago

    You would need to create or adjust a Platform Designer system to first access the external RAM and then connect it to the Nios. It's certainly possible.

    • Rodo's avatar
      Rodo
      Icon for Occasional Contributor rankOccasional Contributor
      4 years ago

      I read this in AN730 after I posted this question. so I think it may not be possible. But I'm not sure (added Bold by me). ERAM and OCRAM seems to be the same thing.

      1.5.2 Boot Option 3: Nios II Processor Application Executes in-place from OCRAM

      The on-chip memory is initialized during FPGA configuration with data from a Nios II application image. This data is built into the FPGA configuration bitstream, the programmer object file. This process eliminates the need for a boot copier, as the Nios II application is already in place at system reset.


      This option will not work in any of the following situations:
      • When you select a configuration mode that does not support ERAM initialization.
      • After a soft reset where the memory contents have been modified by the
      application and the application code has been corrupted.

      1.2 Abbreviations
      Table 1. List of Abbreviations

      ERAM Embedded Random Access Memory