WDB in VxWorks

    The VxWorks WDB(Wind DeBug) target agent is a target-resident, run-time facility that is required for connecting host tools to a VxWorks target system. The WDB agent contains a compact implementation of UDP/IP, and a proprietary RPC messaging protocol called WDB. The WDB protocol uses the Sun Microsystems specification for External Data Representation (XDR) for data transfer.

     WDB can be configured for system mode debugging, task mode debugging, or both (switching between the two modes under the control of host tools). In task mode, WDB runs as a kernel task. In system mode, WDB operates independently of the kernel, and the kernel is under WDB’s control. With system mode, WDB can be started before VxWorks is running, which can be particularly useful in the early stages of porting a BSP to a new board.(WDB可以被配置为系统级调试模式、任务级调试模式，或者两种模式同时存在。在任务级模式下，WDB以内核任务的模式运行。在系统级模式下，WDB独立于系统内核运行，并且可以控制内核的运行。WDB能够在VxWorks内核启动前运行，这在BSP开发的初期调试非常有用。)