W88113C Datasheet, PDF (98/102 Pages) Winbond – ATAPI CD-ROM DECODER & CONTROLLER

W88113C
5.5 Audio-playback
5.5.1 Configuration Phase
1. Configure input/output pin for Audio-playback through APCNF (90h).
- Bit 6: Audio Playback Interrupt Enable
- Bit 4: Audio Reference Clock Select
- Bit 3,2: Audio Input Reference Clock Setting
- Bit 1:0: Audio Data Output Setting
2. Select Audio-playback output format through APFMT (91h).
After configuration, the pins ABCK (6) becomes active but data pin keep "mute."
5.5.2 Playback Phase
If the desired data sectors are buffered in DRAM, the following steps can trigger audio playback:
1. Set Audio-playback start block through APBKH/L (93h/92h).
2. Enable Audio-playback by setting APEN (90h.7) high.
3. Wait for interrupt or polling flag APIb (01h.r2).
4. If APIEN (90h.6) is enabled, write APACK (97h,w) to deactivate audio-playback-interrupt.
5. If buffer is not empty or end of command, go to step 3.
6. Disable Audio-playback by setting APEN (90h.7) low.
The status of playback is directly controlled by the setting of APEN (90h.7). So the buffer should be
carefully managed to prevent noise or broken song.
5.5.3 IEC-958 Digital Audio Output
The digital output function complies with the IEC-958 standard. This function is automatically
enabled after configuration of audio playback function.
DA0EN HSTS1-0 ARST1-0
(87h.7) (2Fh.w5-4) (2Fh.w3-2)
Digital Audio Output Pin
1
xxb
xxb
x
01b
xxb
x
xxb
01b
pin URS (32)
pin HRSTb (21)
pin ARSTb (60)
default
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Publication Release Date: Mar. 1999
Revision 0.61