GS3140 Datasheet, PDF (27/40 Pages) Semtech Corporation – Multi-Rate Adaptive 3G SDI Equalizer

4.11.8 Auto-increment Read/Write Access
Auto-increment read/write access timing for the GSPI interface is shown in Figure 4-13
to Figure 4-17.
Auto-increment mode is enabled by the setting of the AUTOINC bit of the Command
Word.
In this mode, multiple Data Words can be read from/written to the device using only one
starting address. Each access is initiated by a high-to-low transition of the CS pin, and
consists of a Command Word and one or more Data Words. The internal address is
automatically incremented after the first read or write Data Word, and continues to
increment until the read or write access is terminated by a low-to-high transition of the
CS pin.
Note: Writing to HOST_CONF_REG_0 using Auto-increment access is not allowed.
The maximum interface clock rate is 32MHz and the inter-command delay time
indicated in the diagram as t_cmd, is a minimum of 3 SCLK clock cycles.
For read access, the time from the last bit of the first Command Word to the start of the
data output of the first Data Word as defined by t₅, will be no less than 4 SCLK cycles at
32MHz. All subsequent read data accesses will not be subject to this delay during an
Auto-Increment read.
SCLK
CS
SDIN
SDOUT
COMMAND
COMMAND
DATA 1
DATA 1
DATA 2
DATA 2
Figure 4-13: GSPI Write Timing – Auto-Increment with Loop-Through Operation (default)
SCLK
CS
SDIN
SDOUT
COMMAND
DATA 1
DATA 2
Figure 4-14: GSPI Write Timing – Auto-Increment with GSPI Link Disable Operation
SCLK
CS
SDIN
SDOUT ^High-Z
COMMAND
COMMAND
DATA 1
DATA 1
Figure 4-15: GSPI Write Timing – Auto-Increment with Bus-Through Operation
DATA 2
DATA 2
GS3140
Final Data Sheet
PDS-060939
Rev.1
May 2015
www.semtech.com
27 of 40
Semtech
Proprietary & Confidential