XA (CD-ROM Voice Data): Difference between revisions
| Revision as of 02:46, 23 October 2026 RemmyLee (SPU and CD-ROM at register depth; CPU overview rewritten) | Revision as of 02:47, 23 October 2026 RemmyLee (Formats: Sony paragraph voice; HMD, RSD extended files, full BS code book; sprite editor formats) | ||
| Line 10: | Line 10: | ||
| ## Overview | ## Overview | ||
| − | XA is the PlayStation CD-ROM XA voice data format. The typical extension in DOS is ".XA".[^ff131] | + | XA is the PlayStation CD-ROM XA voice data format, and its typical extension in DOS is ".XA". The format is based on the CD-ROM XA System Description of May 1991, and the XA file output by RAW2XA has a sub-header.[^ff131] |
| − | The XA format is based on the CD-ROM XA System Description of May 1991. The XA file output by RAW2XA has a sub-header.[^ff131] | + | The PlayStation plays back ADPCM audio data as specified in the CD-ROM XA (eXtended Audio) standard, which Sony calls XA-ADPCM audio. XA-ADPCM audio is sent directly from the CD-ROM decoder to the SPU without using main memory. Four types are supported:[^ff16] |
| − | The PlayStation plays back ADPCM audio data as specified in the CD-ROM XA (eXtended Audio) standard. Sony calls this XA-ADPCM audio.[^ff16] | ||
| − | |||
| − | ## Audio Types | ||
| − | |||
| − | The PlayStation supports four types of XA-ADPCM audio:[^ff16] | ||
| − | |||
| Table: XA-ADPCM audio data types supported by PlayStation | Table: XA-ADPCM audio data types supported by PlayStation | ||
| Line 29: | Line 23: | ||
| | 18.9 kHz | Monaural | | | 18.9 kHz | Monaural | | ||
| − | XA-ADPCM audio goes from the CD-ROM decoder to the SPU without using main memory.[^ff16] | ||
| − | |||
| ## Interleave | ## Interleave | ||
| − | XA-ADPCM audio sectors are interleaved with gap sectors on the CD-ROM.[^ff16] | + | When XA-ADPCM audio is played back, its sectors must be interleaved with gap sectors on the CD-ROM. The ratio of data sectors to gap size depends on the type of audio and on the playback speed of the CD-ROM. In the table below a lower sampling frequency or a monaural sound therefore takes one audio sector in a longer run of sectors.[^ff16][^ff17] |
| − | The ratio of data to gap depends on the audio type and the playback speed.[^ff17] | ||
| − | |||
| − | The ratios are as follows: | ||
| − | |||
| − | |||
| Table: Data/gap ratios | Table: Data/gap ratios | ||