Philips Semiconductors
STB5860 (Set-Top Box) STB concept
Preliminary specification
OM5730
1.2.2 CPU RELATED FEATURES
• External SDRAM self test
• Asynchronous interface possible with external
microcontroller
• Support of fast DMA transfer
• High speed/low latency interface with second graphics
SDRAM
• Byte access to the full SDRAM in the upper 16-Mbit
address range
• Fast 16-bit data plus 22-bit address synchronous
interface with external controller at up to 40.5 MHz
• Support of Motorola ColdFire and 68xxx interfaces as
well as LSI L64108 interface.
1.2.3 MPEG2 SYSTEM FEATURES
• Support for seamless time base change (edition)
• Processing of errors flagged by channel decoding
section.
1.2.4 MPEG2 VIDEO FEATURES
• Decoding of MPEG2 video up to main level and main
profile
• Output picture format: CCIR-601 4 : 2 : 2 interlaced
pictures; picture format 720 to 576 at 50 Hz or
720 to 480 at 60 Hz
• Support of constant and variable bit rates up to
15 Mbits/s for the elementary stream
• Digital video input/output interface on 8-bit,
27 MHz (CbYCrY multiplexed bus), at a CCIR-656
format
• Analog video output interface on both the RGB and
Y/C/CVBS formats (internal digital encoder)
• Horizontal and vertical pan and scan allows the
extraction of a window from the coded picture
• Flexible horizontal scaling from 0.5 up to 4 allows easy
aspect ratio conversion including support for 2.21 : 1
aspect ratio movies; in case of shrinking an anti-aliasing
pre-filter is applied
• Vertical scaling with fixed factors 0.5 and 0.75;
factor 0.75 is used for letter-box presentation, 1 or 2;
factor 0.5 realizes picture shrink
• Factor 2 can be used for up-conversion of pictures with
288 (240) lines or less
• Horizontal and vertical scaling can be combined to scale
pictures to 1⁄4 their original size, thus freeing up screen
space for graphic applications like Electronic Program
Guides (EPGs)
• Non full screen MPEG pictures can be displayed in a
box of which position and background colour are
adjustable by the external microcontroller; structured
background is available as part of the graphic features
• Nominal video input buffer size for MP at ML 27-Mbit
• Decoding and presentation can be independently
handled under CPU control
• Various trick modes under control of external
microcontroller
• Freeze field/frame on I- or P-frames; restart on I-picture
• Freeze field on B-frames; restart at any moment
• Scanning and decoding of I- or I- and P-frames in a
IBP sequence
• Single-step mode
• Repeat/skip field for time base correction
• Repeat/skip frame for display parity integrity.
1.2.5 MPEG2 AUDIO FEATURES
• Decoding of 2 channel, layer I and II MPEG audio;
support for mono, stereo, intensity stereo and dual
channel mode
• Constant and variable bit rates up to 448 kbits/s
• Supported audio sampling frequencies:
48, 44.1, 32, 24, 22.05 and 16 kHz
• Selectable output channel in dual channel mode
• Dynamic range control at output
• Independent channel volume control and programmable
inter-channel crosstalk through a baseband audio
processing unit
• Muting possibility via (external) controller; automatic
muting in case of errors
• Generation of ‘beeps’ with programmable tone height,
duration and amplitude
• Support for up to 8 channels linear Pulse Code
Modulated (PCM) elementary audio streams with
8, 16, 20 and 24 bits/sample and bit rates up to
6.144 Mbits/s
• 96 kHz Linear Pulse Code Modulated (LPCM) samples
will be mapped to a 48 kHz multi-channel format
1999 Aug 25
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