Chapter 1

Introduction

This chapter describes the ARM PrimeCell Advanced Audio CODEC Interface (PL041). It contains the following section:

•About the ARM PrimeCell AACI (PL041) on page 1-2.

Introduction

1.1About the ARM PrimeCell AACI (PL041)

The ARM PrimeCell Advanced Audio CODEC Interface (AACI) is an Advanced Microcontroller Bus Architecture (AMBA) slave block that connects to the Advanced Peripheral Bus (APB). The PrimeCell AACI provides communication to off-chip CODECs that support the AC-link protocol.

Examples of these CODECs include:

•the WM9704Q from Wolfson Microelectronics Ltd

•the CS4299 from Cirrus Logic

•and the LM4549 from National Semiconductor Corporation.

AC97 CODECs offer a route for high-quality audio, modem support, and provision for headsets.

1.1.1Features of the PrimeCell AACI

The PrimeCell AACI has the following features:

•Four channels are available and can be in operation simultaneously. This allows support for four different sample rates simultaneously.

•The channels can be serviced either by Direct Memory Access (DMA) or by the processor.

•Each channel has transmit and receive FIFOs.

•The four channels allow independence between modem, audio, headset and microphone channels.

Introduction

Figure 1-1 is a simplified block diagram of a PrimeCell AACI.

Figure 1-1 Simplified block diagram of a PrimeCell AACI showing one channel

Introduction