Patent ID: 8065026

Claim:
A vehicle computer system comprising: an audio entertainment subsystem to play audio data received from one or more audio sources, the audio entertainment subsystem including a synchronization circuit to synchronize a first rate at which a first direct memory access (DMA) circuit writes the audio data into a memory with a second rate at which at which a second DMA circuit reads a previously written audio data from the memory, wherein the synchronization circuit uses interrupts generated in the first and the second DMA circuits to synchronize the first rate and the second rate, wherein thread and device drivers controlling the first DMA circuit and controlling the second DMA circuit are different; a user-removable computer independent from the entertainment subsystem, the computer being capable of running one or more application programs; and an application program interface embodied on a computer-readable medium to define an interface between application programs running on the computer and the audio entertainment subsystem, the application program interface having functions that are callable by an application program to control the audio entertainment subsystem.