IBM39STB032xx
IBM39STB034xx
Preliminary
STB032xx and STB034xx Digital Set-Top Box Integrated Controllers
• Performs MPEG-1 and MPEG-2 PES audio parsing, and also accepts audio elementary streams. Parses
and stores ancillary data into external memory for later use by the host processor.
• Supports 16-kHz, 22.05-kHz, 24-kHz, 32-kHz, 44.1-kHz, and 48-kHz audio sampling frequencies.
• Supports audio/video synchronization through PTS/STC comparison with each audio frame.
• Supports Karaoke Mode for Dolby Digital and PCM playback.
• Supports an encoded audio bit rate up to 640 Kbps. This bit rate only pertains to encoded bitstream data.
• Includes Audio Clip Mode for PES, ES, and PCM formats with byte address granularity and 2MB maxi-
mum per clip buffer.
• Allows PCM Mixing with primary audio stream input including sample rate conversion. PCM audio data
supplied via secondary clip mode feature.
• Supports expandable rate buffer size selectable from 4K to 64K (in 4K increments).
• Uses a re-locatable rate buffer region, with a programmable base register (128-byte location granularity).
• Has a re-locatable PTS Value and Ancillary data region, using a programmable base register with 128-
byte location granularity.
• Uses a locatable Audio Temporary Data and Decoded Audio Data Bank region (programmable base reg-
ister with 128-byte location granularity with additional offset register).
• Includes 256x and 512x DAC sampling clock frequency configurations.
• Has a programmable stream ID register with corresponding 8-bit enable field.
• Provides three PCM output formats in 16- or 20-bit precision:
2
- I S
- Left-justified
- Right-justified
• Performs audio bitstream error concealment, either by frame repeats or muting, due to loss of synchroni-
zation or detection of CRC errors.
• Performs MPEG error checking using frame size calculation for each frame.
• Provides de-emphasis pins that interface to external de-emphasis circuitry.
• Provides Dolby Surround Mode (dsurmod) pins that interface to external surround mode circuitry.
• Provides a programmable interface that supports the following:
- Play, stop, and mute
- Rate buffer purge to support channel and mode changes
- Provides a compressed buffer full indicator
- Synchronization enable/disable for PTS-STC comparison
• Includes SPDIF meeting IEC61937 and IEC60958 specs.
• Supports enhanced IEC61937 S/P DIF Channel Status bit by including 16 SPDIF Channel Status bits,
with host control over most of the bits.
• Inserts host-controlled validity bit into SPDIF sub-frame via DCR register.
STB03_sds_041800.fm.01
April 18, 2000
Architecture and Subsystem Information
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