Abstract:

This video provides a technical overview of the post-development configuration process for the VxWorks real-time operating system (RTOS). It explains how to scale a VxWorks image by excluding unnecessary components, linking application code, and setting up automatic task spawning for the final product. The tutorial details the crucial role of the Board Support Package (BSP) and its configuration files, such as sysLib.c and config.h. A core part of the explanation is the detailed VxWorks runtime initialization sequence, outlining the order and function of key routines like sysInit, usrInit, kernelInit, and usrRoot. The video differentiates between "romable" images, which contain their own bootstrap code, and "downloadable" images, which are loaded by an external program. Finally, it covers the practical steps of booting a target device, including hardware setup, setting boot parameters, and recognizing a successful boot sequence.

A Guide to Configuring and Booting VxWorks

• 0:00:15 Post-Development Configuration: After development, the VxWorks OS must be configured to exclude unnecessary features, link the final application code, and define the startup process for deployment on ROM, Flash, or via network download.
• 0:00:42 Scaling with the Project Facility: The Project Facility is the primary tool for configuring VxWorks images. It includes an "autoscale" feature that analyzes application code to automatically include required OS components and dependencies.
• 0:01:50 Application Startup Code: Developers can add custom startup logic by editing the userAppInit() function in the usrAppInit.c file. This code is executed at the end of the system's initialization sequence to launch the main application tasks.
• 0:02:43 Critical BSP Configuration Files: Key Board Support Package (BSP) files like sysLib.c (for hardware initialization functions) and config.h (for system-wide definitions) are central to tailoring VxWorks for specific hardware.
• 0:03:37 The VxWorks Initialization Sequence: The system boots using a strict sequence of routines: sysInit -> usrInit -> usrKernelInit (initializes core libraries like tasking and semaphores) -> kernelInit -> usrRoot (the first task, which starts other tasks, including userAppInit).
• 0:05:26 Romable vs. Downloadable Images: The video explains the two primary image types. Romable images are self-contained and include bootstrap code (romStart) to copy themselves from ROM to RAM. Downloadable images are simpler and rely on an external boot program to load them into RAM.
• 0:07:41 ROM-Based Startup: A ROM-based system uses romInit.s for minimal hardware setup, then executes romStart.c to copy the OS to RAM before proceeding with the standard kernel initialization.
• 0:09:26 Booting a Target Device: To boot a VxWorks target, the hardware must be configured (e.g., setting jumpers), and boot parameters (like IP address, hostname, and gateway) must be set, often over a serial connection using the VxWorks boot ROMs.
• 0:10:29 Successful Boot Output: A successful boot is indicated by console messages confirming the image has been loaded and is running, though the exact text varies depending on the VxWorks version and target board.
• 0:14:26 Future Content: The creator mentions plans to create a similar tutorial series for the FreeRTOS real-time operating system.