Architecture

STM7710

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2.3

External memory interface (EMI)

The EMI is a 16-bit general-purpose interface for attaching system Flash or synchronous

Flash devices and peripherals. Up to 5 separate banks are available, each capable of its

own strobe timing configuration and each with its own chip select signal. Two banks provide

PC-Card compatible strobes for implementing a DVB-CI or CableCard (POD) module

interface.

2.4

Local memory interface (LMI)

The LMI is a 32-bit, high-bandwidth memory interface that enables a unified data memory

architecture through the use of DDR SDRAM. CPU instructions can also be placed here. It

can operate in a 16-bit or 32-bit configuration and has a target operating frequency of

200 MHz for a peak bandwidth of 1.6 Gbyte/s. In a 32-bit configuration, the LMI supports

one x32 device or two x16 devices. 64-Mbit, 128-Mbit or 256-Mbit DDR devices can be used

providing a maximum capacity of 64 Mbytes.

To get the maximum transfer efficiency from the interface, the LMI includes optimizations in

the control of the page structure of DDR DRAMs.

2.5

Transport subsystem

The transport stream subsystem comprises the TS merger/router and a programmable

transport stream interface (PTI).

2.5.1

Transport stream input/output

Transport streams are input to the STM7710 through one of three interfaces. Two of these

are parallel inputs which can also be configured for serial input if required. The third is a

bidirectional parallel interface that can be configured as an input or output.

Figure 4.

Transport-stream subsystem

TS merger

TSIN0

parallel or serial

TSIN1

parallel or serial

TSIN2

parallel or serial input

NRSS-A interface (serial)

alternative functions on PI01

PTI

SWTS

Alt out

STBus

or parallel output