Hitachi 32LD8D20E Service Manual page 7

The TVT provides an integrated general-purpose, fully 8051-compatible microcontroller
with television-specific hardware features. The microcontroller has been enhanced to
provide powerful features such as memory banking, data pointer, additional interrupts,
shared memory access etc.
The TVT has an internal XRAM of 32 KB and a BOOT ROM of 4 KB. For operation the
code is fetched from a 16bit FLASH, which can be addressed up to 1 MByte.
The controller with dedicated hardware does most of the internal TTX acquisition
processing, transfers data to/from external memory interface, and receives/transmits
data via I2C-bus interface. In combination with dedicated hardware, the slicer stores
TTX data in a VBI buffer of 1 KB. The microcontroller firmware performs all the
acquisition tasks (hamming and parity checks, page search, and evaluation of header
control bits) once per field. Additionally, the firmware can provide high-end Teletext
features like Packet-26 handling, FLOF/TOP and list-pages. The interface-to-user
software is optimised for minimal overhead. TVT is realised in deep submicron
technology with 1.8 V supply voltage and 3.3 V I/O (TTL compatible).
16 analog video inputs (4xCVBS/Y/C + 3xRGB/YCrCb/YPrPb)
Video input switch matrix
3 analog video outputs (integrated Y+C adder)
24-bit RGB/H/V/clk input (e.g. ext. DVI decoder) or 656 8bit input
656 8bit input/output (e. g. for external high-end up conversion by FRCA)
Multi-standard color decoder PAL/NTSC/SECAM including all substandards
2D adaptive comb filter for PAL/NTSC with vertical peaking
3D-comb filter for PAL/NTSC (Optional)
Macrovision compliant multi-standard sync processing
Trilevel sync slicer for HDTV
Macrovision detection
High-quality soft mixer controlled by Fast Blank (alpha blending)
Fastblank monitor via I2C
Noise measurement
Letterbox detection (auto-wide)
Split screen (OSD and video side by side) and AV PIP
5.4 Controller Features
The TVT is a Teletext decoder for decoding World System Teletext data, as well as
Video Programming System (VPS), Program Delivery Control (PDC), and Wide-Screen
Signalling (WSS) data used for PALplus transmissions (line 23). The device also
supports Closed Caption acquisition and decoding.
The TVT provides an integrated general-purpose, fully 8051-compatible microcontroller
with television-specific hardware features. The microcontroller has been enhanced to
provide powerful features such as memory banking, data pointer, additional interrupts,
shared memory access etc.
High performance 8-bit microcontroller, 8051 instruction set compatible
81 MHz system clock, two machine cycles per instruction
On-chip debug support (OCDS)
Up to 512 kByte in system program Flash
256 byte on-chip program RAM
128 byte on-chip extended stack RAM