1. Overview

1.1 Purpose

The PCM / ADPCM playback library is a library for easy PCM playback on SEGA SATURN.

1.2 Features

PCM playback is easy

The user calls the PCM task function on a regular basis.
The library reads from a CD, manages ring buffers, manages time, supplies data to PCM buffers, and issues commands to sound drivers.

ADPCM compatible

You can play back ADPCM compressed data while decompressing it.
ADPCM is a method specified as a data format for CD-ROM XA Audio, and can achieve excellent sound quality with a compression ratio of about 1/4.

Supports 4 types of file formats

1. AIFF format (PCM uncompressed)
2. CD-ROM XA Audio format (ADPCM compression)
3. Designated ADPCM format (CRC Research Institute AudioStack output format)
4. SaturnPCM format (PCM uncompressed)

Pause function

The hardware does not have a pause function for PCM playback, but you can easily pause it using this library.

Multi playback

You can play 4 PCMs at the same time.
It can be applied to play BGM and to pronounce the lines of three people asynchronously.
(Cannot contain more than one ADPCM compressed data)

1.3 System image

The following figure shows the system image of this library.

Figure 1.1 System image (playback of PCM uncompressed data)

Figure 1.2 System image (playback of ADPCM compressed data)