AD9925BBCZRL datasheet(43/96 Pages) AD

43 / 96 page

AD9925

Rev. A | Page 43 of 96

FG_TRIG OPERATION

The AD9925 contains an additional signal that may be used in

conjunction with shutter operation or general system operation.

The FG_TRIG signal is an internally generated pulse that can be

output on the VSUB or SYNC pins for system use or combined

with the VSUB registers to create a four-toggle VSUB signal.

The FG_TRIG signal is generated using the start polarity and

first and second toggle position registers, programmable with

line and pixel resolution. The field placement of the FG_TRIG

pulse is matched to the field count specified by the MODE reg-

ister operation. The FG_TRIGEN register contains a 3-bit value

to specify which field count will contain the FG_TRIG pulse.

Figure 53 shows how the FG_TRIG pulse is generated using

these registers.

After the FG_TRIG signal is specified, it is enabled using Bit 3

of the FG_TRIGEN register. By default, the FG_TRIG will be

mapped to the SYNC output, as long as the SYNC pin is config-

ured as an output (SYNCENABLE = 1). Alternatively, the

FG_TRIG pulse may be mapped to the VSUB output by

writing a 1 to the SHUT_EXTRA Register Bit 3.

One final application for the FG_TRIG signal is to combine it

with the existing VSUB signal to generate additional toggle

positions. By setting the SHUT_EXTRA Bit 8 to a 1, the VSUB

toggles and FG_TRIG toggles are XOR’d together and sent to the

VSUB output. Figure 52 and Figure 54 show this application in

more detail.

FG_TRIG

INTERNAL

VSUB

INTERNAL

VSUB

OUTPUT

SHUT_EXTRA[8]

SHUT_EXTRA[3]

XOR

2:1

Figure 52. Combining the Internal FG_TRIG and Internal VSUB Signals

Table 21. FG_TRIG Operation Registers

scription

Address

Bit Width

SYNCENABLE

0x12

[0]

1: Configures SYNC Pin as an Output. By default, the FG_TRIG signal outputs on the SYNC pin.

VSUBON

0x68

[12:0]

Controls VSUB O

with VSUB signa

n Position and

Polarity. When SHUT_Extra [8] = 1, FG_TRIG toggles are combined

SHUT_EXTRA

0xE7

[8:0]

Selects Whether FG_TRIG Sign

[2:0] Set to 0.

[3] Set = 1 to send FG_TRIG signal to VSUB pin.

bine FG_TRI

al Is Used with VSUB.

[7:4] Set to 0.

[8] Set = 1 to com

G and VSUB signals.

FG_TRIGEN

0xEB

[3:0]

FG_TRIG Enable.

[2:0] Selects field

[3] Set = 1 to enab

count for pulse

d counter).

le FG_TRIG sign

(based on mode fiel

al output.

FG_TRIGPOL

0xF2

[0]

FG_TRIG Start Polarity.

FG_TRIGLINE1

0xF3

[11:0]

FG_TRIG First Toggle Position, Line Location.

FG_TRIGPIX1

0xF4

[12:0]

FG_TRIG First Toggle Position, Pixel Location.

FG_TRIGLINE2

0xF5

[11:0]

FG_TRIG Second Toggle Position, Line Location.

FG_TRIGPIX2

0xF6

[12:0]

FG_TRIG Second Toggle Position, Pixel Location.

AD9925BBCZRL 数据表(PDF) 43 Page - Analog Devices

AD9925BBCZRL 数据表(HTML) 43 Page - Analog Devices

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96

数据表下载

链接网址

AD9925BBCZRL 数据表(PDF) 43 Page - Analog Devices

AD9925BBCZRL 数据表(HTML) 43 Page - Analog Devices

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96

数据表 下载

链接网址

数据表下载