![](http://datasheet.mmic.net.cn/Analog-Devices-Inc/AD9920ABBCZRL_datasheet_100713/AD9920ABBCZRL_101.png)
AD9920A
Rev. B | Page 101 of 112
Table 59. Shutter and GPO Registers
Address
Data
Bits
Default
Value
Update
Type
Name
Description
0x70
[2:0]
0
VD
PRIMARY_ACTION
Select action for primary and secondary counters.
[5:3]
0
SECOND_ACTION
0 = idle (do nothing): autoreset on VD.
1 = activate counter (primary: automatic exposure/read).
2 = RapidShot: wrap/repeat counter.
3 = ShotTimer: delay start of count.
4 = ShotTimer with RapidShot.
5 = SLR exposure (manual).
6 = SLR read (manual).
7 = force to idle.
[13:6]
0
MANUAL_TRIG
1: manual trigger for GP signals when Protocol 1 is selected.
Bit 6: GP1 manual trigger.
Bit 13: GP8 manual trigger.
0x71
[12:0]
0
VD
PRIMARY_MAX
Primary counter maximum value.
[24:13]
0
SECOND_MAX
Secondary counter maximum value.
[27:25]
0
VDHD_MASK
Mask VD/HD during counter operation.
0x72
[12:0]
0
VD
PRIMARY_DELAY
Number of fields to delay before the next primary count (exposure)
starts. For ShotTimer with RapidShot, the delay value is used between
each repetition.
[13]
0
PRIMARY_SKIP
For ShotTimer with RapidShot, use the primary delay value only before
the first count (exposure).
[26:14]
0
SECOND_DELAY
Number of fields to delay before the next secondary count (exposure)
starts. For ShotTimer with RapidShot, the delay value is used between
each repetition.
[27]
0
SECOND_SKIP
For ShotTimer with RapidShot, use the secondary delay value only
before the first count (exposure).
0x73
[2:0]
0
VD
GP1_PROTOCOL
Selects protocol for each general-purpose signal.
[5:3]
0
GP2_PROTOCOL
0 = idle.
[8:6]
0
GP3_PROTOCOL
1 = no counter association. Use MANUAL_TRIG bits to enable each GP
signal.
[11:9]
0
GP4_PROTOCOL
2 = test use only.
[14:12]
0
GP5_PROTOCOL
3 = test use only.
[17:15]
0
GP6_PROTOCOL
4 = link to mode counter.
[20:18]
0
GP7_PROTOCOL
5 = link to primary counter.
[23:21]
0
GP8_PROTOCOL
6 = link to secondary counter.
7 = keep on.
0x74
[12:0]
0
VD
SGMASK_NUM
Exposure duration (number of fields to mask SG) for LS operation.
[25:13]
0
VD/SG
SUBCKMASK_NUM
Exposure + readout duration (number of fields to mask SUBCK) for LS.
[26]
0x01
VD/SG
SUBCKTOG_UPDATE
0 = SUBCK HP toggles and the registers involved in SUBCK masking
(Register 0x78 and Register 0x74, Bits[27:13]) are updated at SG line.
1 = updated at update line (VD updated).
[27]
0
VD/SG
SUBCKMASK_SKIP1
Skip the SUBCK mask for the first exposure field only.
0x75
[0]
0
VD/SG
Test
Test purpose only. Must be set to 0.
[13:1]
0
SUBCKSUPPRESS
Number of lines after VSG line to begin SUBCK pulses.
[26:14]
0
SUBCKNUM
Number of SUBCK pulses per field. Must be set less than VDLEN.
[27]
0
SG_SUPPRESS
Suppress the SG and allow SUBCK to finish at SUBCKNUM.
0x76
[0]
0
VD/SG
SUBCK_POL
SUBCK start polarity.
[1]
0
TESTMODE
Test use only. Must be set to 0.
0x77
[13:0]
0
VD/SG
SUBCK_TOG1
SUBCK Toggle Position 1.
[27:14]
0
SUBCK_TOG2
SUBCK Toggle Position 2.
0x78
[13:0]
0
VD/SG
SUBCKHP_TOG1
High precision SUBCK Toggle Position 1.
[27:14]
0
SUBCKHP_TOG2
High precision SUBCK Toggle Position 2.
0x79
[25:0]
0
VD
TESTMODE
Test use only. Must be set to 0.