AD9927 Analog Devices, AD9927 Datasheet - Page 31

• Manufacturer Part Number: AD9927
• Description: 14-Bit CCD Signal Processor
• Manufacturer: Analog Devices

VERTICAL SEQUENCES (VSEQ)
The vertical sequences are created by selecting one of the
V-pattern groups and adding repeats, start position, horizontal
clamping, and blanking information. The V-sequences are
programmed using the registers shown in Table 14. Figure 36
shows how the different registers are used to generate each
V-sequence.
The VPATSELA, VPATSELB, VPATSELC, and VPATSELD
registers select which V-pattern is used in a given V-sequence.
Having four groups available allows different vertical outputs to
be mapped to different V-patterns. The selected V-pattern group
can have repetitions added for high speed line shifts or for line
binning by using the VREP registers for odd and even lines.
Generally, the same number of repetitions is programmed
XV1 TO XV24
CLPOB
HBLK
HD
PROGRAMMABLE SETTINGS FOR EACH VERTICAL SEQUENCE:
1
2
3
4
5
6
START POSITION IN THE LINE OF SELECTED V-PATTERN GROUP.
HD LINE LENGTH.
V-PATTERN SELECT (VPATSEL) TO SELECT ANY V-PATTERN GROUP.
NUMBER OF REPETITIONS OF THE V-PATTERN GROUP (IF NEEDED).
START POLARITY AND TOGGLE POSITIONS FOR CLPOB AND PBLK SIGNALS.
MASKING POLARITY AND TOGGLE POSITIONS FOR HBLK SIGNAL.
5
6
V-PATTERN GROUP
1
3
Figure 36. V-Sequence Programmability
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VREP 2
4
2
into both registers. If a different number of repetitions is
required on odd and even lines, separate values can be used for
each register (see the Generating Line Alternation for V-
Sequences and HBLK section). The VSTARTA and VSTARTB
registers specify where in the line the V-pattern group starts.
The VMASK_EN register is used in conjunction with the
FREEZE/RESUME registers to enable optional masking of the
V-outputs. Either or both of the FREEZE1/RESUME1 and
FREEZE2/RESUME2 registers can be enabled.
The line length (in pixels) is programmable using the HDLEN
registers. Each V-sequence can have a different line length to
accommodate various image readout techniques. The maximum
number of pixels per line is 8192. The last line of the field is
programmed separately using the HDLASTLEN register, which
is located in the field register section.
VREP 3
4
AD9927