— Open source software are becoming more widely-used, notably in the server and desktop applications. For embedded systems development, usage of open source software can also reduce development and licensing costs. We report on our experience in developing a Systemon-a-Chip (SoC) audio player using various open source components in both hardware and software parts as well as in the development process. The Ogg Vorbis audio decoder targeted for limited computing resource and low power consumption devices was developed on the free LEON SoC platform, which features SPARC-V8 architecture compatible processor and AMBA bus. The decoder runs on the open source RTEMS operating system making use of the royalty-free open source Vorbis library. We also aim to illustrate the use of hardware/software co-design techniques. Therefore, in order to speed up the decoding process, after an analysis, a computing-intensive part of the decoding algorithm was selected and designed as an AMBA compatible har...