(1)General Description
The TDA5255 contains a slicer for VPS and TTX, an accelerating acquisition hardware module, a display generator for “LEVEL 1” TTX data and a 8 bit
The controller with dedicated hardware guarantees flexibility, does most of the internal processing of TTX acquisition , transfers data to/from the external memory interface and receives/transmits data via I2C and UART user interfaces.
The Slicer combined with dedicated hardware stores TTX data in a VBI 1Kbyte buffer. The
(2)Feature
•Acquisition:
-feature selection via special function register
-simultaneous reception of TTX and VPS
-fixed framing code for VPS and TTX
-programmable framing code window for TTX
-Acquisition during VBI
-direct access to VBI RAM buffer
-Acquisition of packets x/26, x/27, 8/30 (firmware)
-assistance of all relevant checks (firmware)
-
•Display:
-features selectable via special function register
-50/60 Hz display
-level 1 serial attribute display pages
-blanking and contrast reduction output
-8 direct addressable display pages
-12 x 10 character matrix
-96 character ROM (standard G0 character set)
-143 national option characters for 11 languages
-288 characters for X/26 display
-64 block mosaic graphic characters
-32 free addressable characters for OSD in expanded character ROM + 32 inside OSD box
-double height (TOP/BOTTOM)
-conceal/reveal
-transparent foreground/background
-cursor (colour changes from foreground to background colour)
-flash (flash rate 1s)
-programmable horizontal und vertical sync delay
-hardware assisted fast display page erase
-full screen background colour in outer screen
•Synchronization:
display synchronization to sandcastle or Horizontal Sync (HS) and Vertical Sync (VS) with
independent clock systems for acquisition, display and controller
9
