Digital Signal Processing and Applications with the OMAP-L138 eXperimenter

Chapter 7

DSP/BIOS and Platform Support Package

• DSP/BIOS‒ real-time operating system
• DSP/BIOS‒ software kernel foundation platform support package (PSP)

The examples in this chapter illustrate the use of the DSP/BIOS real-time operating system and the platform support package.

DSP/BIOS provides real-time scheduling, analysis, and data transfer capabilities for an application running on a Texas Instruments DSP. The platform support package provides a further level of abstraction and an API for real-time applications.

7.1 INTRODUCTION TO DSP/BIOS

The following examples introduce some of the real-time scheduling features of DSP/BIOS. Example programs from previous chapters are adapted to run as DSP/BIOS applications. The XDS100 emulator built into the eXperimenter board does not support the real-time analysis (RTA) and real-time data transfer (RTDX) features of DSP/BIOS [1].

7.1.1 DSP/BIOS Threads

At the heart of DSP/BIOS is a preemptive real-time scheduler. This determines which one of a number of different threads is executed by the DSP at any given time. For the purposes of this chapter, DSP/BIOS threads are considered to be sections of program code executed by the DSP. The scheduler determines which thread to execute at a particular time according to its type and associated priority. There are several different types of thread that can be used in a DSP/BIOS application.

• Hardware Interrupts (HWIs) have the highest priority in a DSP/BIOS application. Their execution is triggered ...