AD9923ABBCZ datasheet(32/88 Pages) AD

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AD9923A

Rev. 0 | Page 32 of 88

Hold Area Using FREEZE/RESUME Registers

The FREEZE/RESUME registers can also be used to create a

hold area, in which the XV outputs are temporarily held and

then later resume at the point where they were held. As shown

in Figure 44, this is different than using the VMASK register,

because the XV outputs continue from where they stopped (as

opposed to having the pixel counter run continuously), with

any toggle positions that fall between the FREEZE and

RESUME locations being ignored. Signals assigned to Group B

are not affected by the hold area.

XV1

XV11

NOTES

1. WHEN HOLD = 1 FOR ANY V-SEQUENCE, THE FREEZE AND RESUME REGISTERS ARE USED TO SPECIFY THE HOLD AREA FOR GROUP A.

2. ABOVE EXAMPLE: ALL XV-OUTPUTS ARE ASSIGNED TO GROUP A.

3. H-COUNTER FOR GROUP A (XV1 TO XV13) STOPS DURING HOLD AREA.

XV12

HOLD AREA

FOR GROUP A

XV13

FREEZE

RESUME

Figure 44. Hold Area for Group A

XV1

XV11

NOTES

1. ABOVE EXAMPLES: XV12 AND XV13 ARE ASSIGNED TO GROUP B.

2. GROUP B DOES NOT USE HOLD AREA.

XV12

HOLD AREA

FOR GROUP A

XV13

NO HOLD

AREA FOR

GROUP B

FREEZE

RESUME

Figure 45. Group B Does Not Use Hold Area

AD9923ABBCZ Datasheet(PDF) 32 Page - Analog Devices