Daewoo WP-895, Service Manual

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Service manual WP 895/895F, CP885/885F, CP485F
• High-level command language
• FLOF (Fastext), and TOP support
• 10 pages memory on chip (10kB)
4-1-5- Display OSD Features
• 3kB OSD RAM on chip
• WST level 1.5 compliant
• WST level 2 parallel attributes
• 32 foreground/background colours
• programmable colour look-up table
• 1024 mask programmable characters
• 17 national languages
• (Latin, Cyrillic and Greek caracter sets)
• Character matrix 10x10
• 4-color mode for user font
4-1-6- Audio Features
• Three mono inputs
• Two mono outputs
• Programmable channel select
• Volume control for one mono channel
4-1-7- General Features
• Submicron CMOS technology
• Low-power standby mode
• Single 20.25 MHz crystal
• 64-pin PSDIP package
4-1-8- Data Capture
The Video Front End section takes in the analogue Composite Video and Blanking Signal (CVBS), and from this
extracts the required data, which is then decoded and stored in memory.
The extraction of the data is performed in the digital domain. The first stage is to select and convert the analogue
CVBS signal into a digital form. This is done using 8 bit ADC sampling at 20.25 Mhz.
The digital data services transmitted in the VBI are selected and acquired separately form the video part. This is done
by the use of an adaptive data slicer. The following data types can be extracted : 625 line World System Teletext
(WST), VPS, WSS. The data is acquired and decoded by the teletext decoder (TPU), then stored in an SRAM lnterface.
4-1-9- Data Capture Features
• Video Signal Quality detector
• Data Capture for 625 line WST
• Data Capture for VPS data (PDC system A)
• Data Capture for Wide Screen Signalling (WSS) bit decoding
• Real-time capture and decoding for WST Teletext in Hardware, to enable optimised microprocessor throughput
• 10 page memory stored On-Chip