Technicolor - Thomson ICC19, Principles And Maintenance

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REMOTE CONTROL UNIT
ADDRESSING
The IR002, memory for the software and default values, is an EPROM with
capacity up to 512 KB or 4 Mbits.
The 8-bit ST90R92 microcontroller has an address bus (A0-A14) limited to 15
bits. This provides addressing of only 32 KB. Page-swapping is therefore
necessary.
Four output port lines (BS00 through BS05) swap the read-only memory for a
selection of 16 pages compatible with the use of an 8-Mbit memory capacity,
i.e. 1024 KB.
DATA
Data comprising eight bits, labelled D0 through D7, are sent via the data bus.
To prevent any conflict of addresses with the microcontroller internal RAM, an
enable line, called data-strobe, is activated in the low state when the
microcontroller communicates with its ROM. The rest of the time, the IR002 is
in tri-state to free the data bus.
NOTES :
CENTRE DE
FORMATION TECHNIQUE
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