
AD9925
Refer to Figure 51 for each step:
Rev. A | Page 42 of 96
1.
Write to the READOUT register (Addr x61) to specify the
number of fields to further suppress SUBCK while the
CCD data is readout. In this example, READOUT = 3.
Write to the EXPOSURE register (Addr x62) to specify the
number of fields to suppress SUBCK and VSG outputs dur-
ing exposure. In this example, EXPOSURE = 1.
Write to the TRIGGER register (Addr x60) to enable the
STROBE, MSHUT, and VSUB signals and to st
posure/readout operation. To trigger these events (as in
Figure 56), set the register TRIGGER = 31. Readout will
automatically occur after the exposure period is finished.
Write to the MODE register (x1B) to configure the next
five fields. The first two fie
same as the current draft mode fields, and the following
three fields are the still frame readout fields. The registers
for the draft mode field and the three readout fields have
already been programmed.
2.
The VD/HD falling edge will update the serial writes from 1.
3.
If VSUB mode = 0 (Addr x67), VSUB output will turn on at
the line specified in the VSUBON register (Addr x68).
4.
STROBE output turns on and off at the location specified
in the STROBEON and STROBEOFF registers (Addr x6E
to x71).
5.
MSHUT output turns off at the location specified in the
MSHUTOFF registers (Addr x6B and x6C).
6.
The next VD falling edge will automatically start the first
readout field.
7.
The next VD falling edge will automatically s art the sec-
ond readout field.
8.
The next VD falling edge will automatically start the third
readout field.
9.
Write to the MODE register to reconfigure the single draft
mode field timing. Write to the MSHUTON register
(Addr x6A) to open the mech
anical shutter.
10.
VD/HD falling edge will update the serial writes from 9.
VSG outputs return to draft mode timing.
SUBCK output resumes operation.
MSHUT output returns to the on position (active or open).
VSUB output returns to the off position (inactive).
art the ex-
lds during exposure are the