RTEMS BeagleBone Black Hello World Application Workflow

Development Directory Layout

/Users/ningzhang/development
├── rtems
│   └── 7
│       ├── bin
│       ├── arm-rtems7
│       └── share
│
├── src
│   └── rtems
│       ├── waf
│       ├── bsps
│       ├── cpukit
│       └── testsuites
│
├── build-bbb
│   ├── config.log
│   ├── arm-rtems7
│   └── cache
│
└── app
    └── hello
        ├── init.c
        ├── hello.c
        ├── wscript
        ├── waf
        ├── build
        ├── app.bin
        ├── app.bin.gz
        └── rtems-app.img

1. Install RTEMS 7 Toolchain

Install the RTEMS 7 toolchain using RTEMS Source Builder (RSB).

2. Clone RTEMS Source

Clone the RTEMS source tree into:

~/development/src/rtems

3. Create Application Workspace

mkdir -p $HOME/development/app/hello
cd $HOME/development/app/hello

4. Download Waf Build System

curl https://waf.io/waf-2.0.19 > waf
chmod +x waf

5. Initialize Git Repository

git init

6. Add RTEMS Waf Support

git submodule add \
https://gitlab.rtems.org/rtems/tools/rtems_waf.git \
rtems_waf

7. Create Application Source Files

Create:

• init.c
• hello.c
• wscript

8. Configure for BBB BSP

./waf configure \
  --rtems=$HOME/development/rtems/7 \
  --rtems-tools=$HOME/development/rtems/7 \
  --rtems-bsp=arm/beagleboneblack

9. Build the Application

./waf

10. Generate RTEMS Executable

Output:

build/arm/beagleboneblack/hello.exe

11. Convert ELF to Binary

arm-rtems7-objcopy hello.exe -O binary app.bin

12. Compress the Binary

gzip -9 app.bin

13. Create U-Boot Image

mkimage -A arm -O linux -T kernel \
  -a 0x80000000 -e 0x80000000 \
  -n RTEMS \
  -d app.bin.gz rtems-app.img

14. Prepare the Boot Method

Option A: SD Card Boot

Prepare a FAT32 SD card and copy:

• rtems-app.img
• am335x-boneblack.dtb
• uEnv.txt

Option B: TFTP Boot

Configure the host machine as a TFTP server.

Connect the BBB and host through Ethernet.

Configure U-Boot network settings:

ipaddr
serverip

Load the RTEMS image:

tftp 0x80800000 rtems-app.img
tftp 0x88000000 am335x-boneblack.dtb

15. Connect UART Console

Connect the USB-to-TTL serial adapter to the BBB UART pins.

Open the serial console:

screen /dev/cu.usbserial-XXXX 115200

16. Load RTEMS in U-Boot

SD Card Boot

fatload mmc 0 0x80800000 rtems-app.img
fatload mmc 0 0x88000000 am335x-boneblack.dtb

TFTP Boot

tftp 0x80800000 rtems-app.img
tftp 0x88000000 am335x-boneblack.dtb

17. Boot RTEMS

bootm 0x80800000 - 0x88000000

18. Observe Output

Observe RTEMS boot messages and the Hello World output through the UART serial console.