Detailed monitoring of real-time application performance requires timing information based on high-resolution timers. You can extend the range of information available from VxWorks kernel instrumentation by supplying a timestamp driver. For example, if a timestamp driver is available, a precise chronology can be displayed by WindView, a graphical analysis tool for real-time and embedded systems based on VxWorks.

The timer is a hardware facility; a timestamp driver is a software interface to that facility. This appendix describes the standard interfaces for a VxWorks timestamp driver, and discusses the requirements for a hardware timer for use with VxWorks kernel instrumentation. It is not a step-by-step tutorial on the process of writing a timestamp driver.

This appendix is meant for the following readers:

We assume the reader has a working knowledge of the target board hardware. No knowledge of the VxWorks kernel or of WindView is assumed, although experience writing device drivers is helpful.