Chapter 3
Interfaces
The following chapter describes the interfaces of the chip and the
interface operation modes. It consists of the following sections:
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Section 3.1, “Transport Interface,” page 3-1
Section 3.2, “Serial Control Interface,” page 3-2
Section 3.3, “Analog Output Interface,” page 3-3
Section 3.4, “Digital Output Interface,” page 3-6
3.1 Transport Interface
The task of the transport interface is to read the data stream from the
transport source, to identify the position of the synchronization bytes, and
to strip off invalid data. The transport interface can operate in either
parallel or serial mode.
3.1.1 Synchronization
The L64777 can synchronize the transport interface in two ways. In both
modes, it works synchronously with ICLK and reads all signals, including
input data, on the raising edge of ICLK.
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In external synchronization mode, the transport interface specifies
the position of the external sync byte by asserting FSTARTIN to
HIGH during the synch byte input. In serial mode, the interface must
assert the signal HIGH during the first bit (MSB) of the input stream.
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In internal synchronization mode, the L64777 does not require a
block start indication and finds the position of the programmed sync
byte automatically.
L64777 DVB QAM Modulator Technical Manual
3-1
ETC [ ETC ]
