GS1675 datasheet(18/37 Pages) SEMTECH

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GS1675 SD/HD SDI Reclocker

Data Sheet

54174 - 1

June 2011

18 of 37

3.14.4 Clock & Data Timing

The SPI signals are Serial Data Input (SDI), Serial Data Output (SDO), active-low Chip

Select (CS), and Serial Clock Input (SCK). The host interface operates in SPI Mode 0, i.e.

the SDI input will latch data in on the rising edge of SCK. The SDO data output will

transition on falling edges of SCK. Data is transmitted or received on the SPI port MSB

first LSB last.

Figure 3-3: Data Clock Alignment

3.14.5 Single Device Operation

For applications with a single device or applications with multiple devices where daisy

chaining is not desired, the chain position bits C[6:0] should always be set to 0. As a

by-product of the daisy chaining feature, Read and Write operations experience a 32

SCK cycle latency from SDI to SDO. For more details on daisy-chaining, refer to

Section 3.14.8 on page 22.

Figure 3-4: 16-bit Command Format

SCK

Cycle #

SDO

SDI

A[4:0]

Read/

Write

Reset

Address

C N[6:0] = `0000000’

Chain Position

GS1675 Datasheet(PDF) 18 Page - Semtech Corporation