Overview

The mpi_loader_extram_hello_world example demonstrates how to build an application running in on-board PSRAM. Such application can be combined with mpi_loader_extram_loader by elftosb tool and boot by mpi_loader_extram_loader.

Hardware requirements

  • Micro USB cable

  • EVK-MIMXRT685 board

  • Personal Computer

Board settings

Prepare the Demo

  1. Connect a micro USB cable between the PC host and the CMSIS DAP USB port (J5) on the board

  2. Example boards\evkmimxrt685\component_examples\mpi_loader\extram_loader should be built and we can then get extram_loader.bin.

  3. Build this example, and we can get extram_hello_world.bin.

  4. Copy all those binaries to elf2sb workspace “input_images” folder identified in boards\evkmimxrt685\component_examples\mpi_loader\mpi_loader_ram.json.

  5. Copy mpi_loader_ram.json to elf2sb workspace “image_config” folder.

  6. Execute elf2sb.exe with mpi_loader_ram.json as parameter. E.g.,

    • elftosb.exe -V -d -f rt6xx -J workspace/image_config/mpi_loader_ram.json

  7. In elf2sb workspace “output_images” folder, you can get the multicore packed image mpi_loader_extram_hello_world.bin.

  8. Write flash config block to flash offset 0x400 (address 0x08000400) and write mpi_loader_extram_hello_world.bin to flash offset 0x1000 (address 0x08001000). E.g. with blhost tool, set board boot mode DIP to Serial ISP [high, high, low], reset the board and use command window to communicate with it (need to identify the COM port).

    • blhost.exe -p COM29 – fill-memory 0x1c000 4 0xc1500051

    • blhost.exe -p COM29 – fill-memory 0x1c004 4 0x20000008

    • blhost.exe -p COM29 – configure-memory 9 0x1c000

    • blhost.exe -p COM29 -t 100000 – flash-erase-region 0x08000000 0x100000

    • blhost.exe -p COM29 – fill-memory 0x1d000 4 0xf000000f

    • blhost.exe -p COM29 – configure-memory 0x9 0x1d000

    • blhost.exe -p COM29 – write-memory 0x08001000 workspace\output_images\mpi_loader_extram_hello_world.bin

  9. Set board boot mode to flash portb boot [low, high, low]

  10. Open a serial terminal with the following settings:

    • 115200 baud rate

    • 8 data bits

    • No parity

    • One stop bit

    • No flow control

  11. Reset the board and you will see the result.

Running the demo CM33

When the demo runs successfully, the terminal will display the following:

Loading finished, now enter external RAM application.
hello world.