| .. _minimal_sample: |
| |
| Minimal sample |
| ############## |
| |
| Overview |
| ******** |
| |
| This sample defines An empty ``main()`` and a set of minimal configurations |
| that provide tests for the smallest ROM sizes possible with the Zephyr kernel. |
| |
| The following configuration files are available: |
| |
| * :file:`mt.conf`: Enable multithreading |
| * :file:`no-mt.conf`: Disable multithreading |
| * :file:`no-preempt.conf`: Disable preemption |
| * :file:`no-timers.conf`:: Disable timers |
| * :file:`arm.conf`: Arm-specific disabling of features |
| |
| Building and measuring ROM size |
| ******************************* |
| |
| In order to compare ROM sizes with different minimal configurations, the |
| following combinations are suggested: |
| |
| * Reel board (Arm architecture) |
| |
| * Multithreading enabled |
| |
| * Reference ROM size: 7-8KB |
| |
| .. zephyr-app-commands:: |
| :zephyr-app: samples/basic/minimal |
| :host-os: unix |
| :board: reel_board |
| :build-dir: reel_board/mt/ |
| :conf: "common.conf mt.conf arm.conf" |
| :goals: rom_report |
| :compact: |
| |
| * Multithreading enabled, no preemption |
| |
| * Reference ROM size: 7-8KB |
| |
| .. zephyr-app-commands:: |
| :zephyr-app: samples/basic/minimal |
| :host-os: unix |
| :board: reel_board |
| :build-dir: reel_board/mt-no-preempt/ |
| :conf: "common.conf mt.conf no-preempt.conf arm.conf" |
| :goals: rom_report |
| :compact: |
| |
| * Multithreading enabled, no preemption, timers disabled |
| |
| * Reference ROM size: 3-4KB |
| |
| .. zephyr-app-commands:: |
| :zephyr-app: samples/basic/minimal |
| :host-os: unix |
| :board: reel_board |
| :build-dir: reel_board/mt-no-preempt-no-timers/ |
| :conf: "common.conf mt.conf no-preempt.conf no-timers.conf arm.conf" |
| :goals: rom_report |
| :compact: |
| |
| * Multithreading disabled, timers enabled |
| |
| * Reference ROM size: 4-5KB |
| |
| .. zephyr-app-commands:: |
| :zephyr-app: samples/basic/minimal |
| :host-os: unix |
| :board: reel_board |
| :build-dir: reel_board/no-mt/ |
| :conf: "common.conf no-mt.conf arm.conf" |
| :goals: rom_report |
| :compact: |
| |
| * Multithreading disabled, timers disabled |
| |
| * Reference ROM size: 2-3KB |
| |
| .. zephyr-app-commands:: |
| :zephyr-app: samples/basic/minimal |
| :host-os: unix |
| :board: reel_board |
| :build-dir: reel_board/no-mt-no-timers/ |
| :conf: "common.conf no-mt.conf no-timers.conf arm.conf" |
| :goals: rom_report |
| :compact: |
| |
