lm9627 National Semiconductor Corporation, lm9627 Datasheet - Page 27

• Manufacturer Part Number: lm9627
• Description: Color Cmos Image Sensor Vga 30 Fps
• Manufacturer: National Semiconductor Corporation

Register Set
Register Name Snapshot Mode Configuration Register 0
Address
Mnemonic
Type
Reset Value
Confidential
7.6
5
4
3
2
1
0
Bit
SsFrames
ShutterEn
ExtSynPol
SnapshotMod
SnapShotPol
IrqPol
Bit Symbol
09 Hex
SNAPMODE0
Read/Write
00 Hex
(continued)
Program to set the number of
frames required before readout
during a snapshot with no external
shutter, (see Figure 18). By
default these two bits are set to 00
resulting in one frame before
readout:
Assert to indicate that an external
shutter will be used during snap-
shot mode. Clear (the default) to
indicate that snapshot mode will
be carried out without the aid of an
external shutter.
Assert to set the active level of the
extsync signal to 0. Clear (the
default) to set the active level of
the extsync signal to 1.
Reserved
Assert to set the snapshot pin to
level mode. In level mode the sen-
sor will continually run snapshot
sequences as long as the snap-
shot pin is held to the active level.
Clear (the default) to set the snap-
shot signal to pulse mode. In
pulse mode the sensor will only
carry out one snapshot sequence
per pulse applied to the snapshot
pin.
Assert to set the snapshot pin to
be active on the positive edge.
Clear (the default) to set the snap-
shot pin to be active on the nega-
tive edge.
Assert to set the active level of the
irq signal to 0, Clear (the default)
to set the active level of the irq
signal to 1.
0
01
10
11
one frame
two frames
three frames
four frames
Description
27
Register Name Snapshot Mode Configuration Register 1
Address
Mnemonic
Type
Reset Value
7
6
5
4
3
2
1
0
Bit
SnapIntEn
SsTrigFlag
SsRdFlag
SsEngage
FtSync
FtBusy
FTriggerNow
FTriggerEn
Bit Symbol
0A Hex
SNAPMODE1
Read/Write
00 Hex.
Assert to enable the snapshot
interrupt generator. Clear (the
default) to disable the interrupt
generator.
(Read Only Bit)
Snapshot trigger interrupt flag.
A logic 1 in this bit indicates that
the generated interrupt on the
irq pin is due to a snapshot trig-
ger. This bit is cleared when
read.
(Read Only Bit)
Snapshot read done interrupt
flag. A logic 1 in this bit indicates
that the generated interrupt on
the irq pin is due to the comple-
tion of a snapshot readout
sequence. This bit is cleared
when read.
Assert to allow a CPU controlled
snapshot sequence. In this
mode the snapshot trigger will
only generate an interrupt to the
CPU and the CPU must manu-
ally start the snapshot sequence
by asserting the FTriggerEn bit
of this register.
Clear (the default) engage an
automatic snapshot sequence.
In auto mode the snapshot
sequence is started as soon as
a snapshot trigger is asserted.
(Read Only Bit)
The internal synchronisation
signal. A logic 1 on this bit indi-
cates a synchronization event is
required. This bit is functionally
equivalent to the external
extsync pin.
(Read Only Bit)
The Frame Trigger Busy bit. A
logic 1 on this bit indicates that
the sensor is busy reading out
pixel data as shown in Figure
18.
Assert to start a snapshot
sequence. The frame trigger
now is functionally equivalent to
the external snapshot pin. The
default is 0.
Assert to enable a snapshot
sequence (see the SsEngage
bit of this register). The default
is 0.
Description
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