GS6152 Datasheet, PDF (17/80 Pages) Semtech Corporation – Multi-Rate 6G UHD-SDI

4.1.2 Input Selection
The GS6152 incorporates a 4:1 input selector which allows the connection of four
independent streams of video/data.
The selector is controllable in three separate ways:
1. The DDI_SEL0 and DDI_SEL1 pins can be used to select the input.
2. A GSPI accessible register can be used to select the input, with the state change
occurring as soon as the register value changes.
3. A GSPI accessible register can be used to select the input, with a rising edge on the
STROBE pin triggering a change to the next state.
Since these states are mutually exclusive, the DDI_SEL0 pin is shared with the STROBE
function.
In the case of using the DDI_SEL0/STROBE and DDI_SEL1 pins (#1 above) or the STROBE
pre-select method (#3 above), the input selector will switch within 1μs of the change of
state on the corresponding pin(s). This strict timing requirement is not maintained when
using GSPI register selection (#2 above).
Each of the device’s four inputs is selected as shown in Table 4-2.
Table 4-2: Pin and Register Settings for Input Selection
Register Settings
INPUT_SELECTION_CONTROL
7_h[9:8]
X0 (default)
X0 (default)
X0 (default)
X0 (default)
01
01
01
01
DDI_SELECT
7_h[11]
X
X
X
X
0
0
1
1
DDI_SELECT
7_h[10]
X
X
X
X
0
1
0
1
11
0
0
11
0
1
11
1
0
Pin Settings
Differential
DDI_SEL1
DDI_SEL0/
STROBE
High-speed
Input Selected
LOW
LOW
HIGH
HIGH
X
X
X
X
X
X
X
LOW
HIGH
LOW
HIGH
X
X
X
X
on
LOW-to-HIGH
transition
on
LOW-to-HIGH
transition
on
LOW-to-HIGH
transition
DDI0, DDI0
DDI1, DDI1
DDI2, DDI2
DDI3, DDI3
DDI0, DDI0
DDI1, DDI1
DDI2, DDI2
DDI3, DDI3
DDI0, DDI0
DDI1, DDI1
DDI2, DDI2
GS6152
Final Data Sheet
PDS-060984
Rev.2
July 2015
www.semtech.com
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Semtech
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