GS4910B GENNUM [Gennum Corporation], GS4910B Datasheet - Page 77

• Manufacturer Part Number: GS4910B
• Description: HD/SD/Graphics Clock and Timing Generator with GENLOCK
• Manufacturer: GENNUM [Gennum Corporation]

3.12.1 Command Word Description
3.12.2 Data Read and Write Timing
MSB
R/W
RSV = Reserved. Must be set to zero.
MSB
D15
RSV
D14
The command word consists of 16 bits transmitted MSB first and includes a
read/write bit, an Auto-Increment bit and a 12-bit address.
command word format and bit configurations.
Command words are clocked into the GS4911B/GS4910B on the rising edge of the
serial clock, SCLK, which operates in a burst fashion.
When the Auto-Increment bit is set LOW, each command word must be followed
by only one data word to ensure proper operation. If the Auto-Increment bit is set
HIGH, the following data word will be written into the address specified in the
command word, and subsequent data words will be written into incremental
addresses. This facilitates multiple address writes without sending a command
word for each data word.
Auto-Increment may be used for both read and write access.
Figure 3-15: Command Word Format
Figure 3-16: Data Word Format
Read and write mode timing for the GSPI interface is shown in
Figure 3-18
When several devices are connected to the GSPI chain, only one CS should be
asserted during a read sequence.
During the write sequence, all command and following data words input at the
SDIN pin are output at the SDOUT pin as is. Where several devices are connected
to the GSPI chain, data can be written simultaneously to all the devices that have
CS set LOW.
36655 - 2
RSV
D13
AutoInc
D12
respectively. The timing parameters are defined in
April 2006
A11
D11
A10
D10
A9
D9
R/W: Read command when R/W = 1
A8
D8
Write command when R/W = 0
A7
D7
GS4911B/GS4910B Data Sheet
A6
D6
A5
D5
A4
D4
Figure 3-15
A3
D3
Figure 3-17
Table
A2
D2
3-12.
shows the
A1
77 of 113
D1
and
LSB
LSB
A0
D0