Technicolor - Thomson ICC19, Principles And Maintenance

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DATA MANAGEMENT
ICC19 chassis are 50-Hz or 100-Hz compatible. They are controlled by an 8-
bit microcontroller, the ST90R92.
It communicates via an address and data bus with its external program
memory, an EPROM, IR002, with a basic capacity of 256 KB that can be
extended to 1024 KB.
Two I2C buses dialog with the various programmable circuits installed on the
chassis.
In conjunction with IR003 (EEPROM), the I2C1 bus saves the parameters and
settings required by the television set.
It manages the ON/OFF command, the line and frame time base circuits, audio
and video switching, and settings including the USYST voltage.
In conjunction with the tuner frequency synthesis, the I2C2 bus controls video
processing and the 100-Hz digital converter.
It also controls an 8-bit IR004 universal register (EXPANDER), which increases
the number of control ports.
The M3L bus is intended for the TELETEXT module (MEGATEXT version).
The microcontroller analyses and distributes the commands from peripheral
devices, the infrared receiver, the keypad, and the red LED via several input
and output lines.
The INT line is the HALT input of the microcontroller, and the MAIN RESET
output of the TELETEX module.
NOTES :
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