camisp-033
Shutter
frame
counter
Shutter
delay
counter
Shutter
length
counter
Prestrobe
frame
counter
Prestrobe
delay
counter
Prestrobe
length
counter
Strobe
frame
counter
Strobe
delay
counter
Strobe
length
counter
cam_strobe
cam_shutter
c
a
m
_
m
c
lk
Clock
divider
C
S
I2
A
_
E
O
F
V
S
Control-signal generator
CNTCLK
CNTCLK
CNTCLK
CNTCLK
CNTCLK
CNTCLK
c
a
m
_
g
lo
b
a
l_
re
s
e
t
Reset
length
counter
CNTCLK
TCTRL_CTRL[28:27] INSEL
TCTRL_CTRL[31] GRESETDIR
O
R
CNTCLK
Prestrobe
replay
counter
Prestrobe
replay
counter
C
S
I1
_
E
O
F
CNTCLK
SHUTTER
PRESTROBE
STROBE
Reset
length
counter
C
S
I2
C
_
E
O
F
Public Version
www.ti.com
Camera ISP Functional Description
Figure 6-76. Camera ISP Timing Control Control-Signal Generation
The control-signal generator gathers precise timings for the cam_strobe and cam_shutter signals, to
assert and deassert the signals at known times. The timing-control-signal generator can be synchronized
either on the vertical synchronization signal coming from the CSI2A (VP_VS from CSI2A), CSI2C (VP_VS
from CSI2C), CSI1/CCP2B(VP_VS from CSI1/CCP2B),or PARALLEL interface (cam_vs), or on an
externally-generated cam_global_reset signal.
A multiplexer controls which of the CSI2A, CSI1/CCP2B or CSI2C, and PARALLEL interface drives
control-signal generation. This multiplexer can also select the externally-generated cam_global_reset
signal as the trigger event. The
[31] GRESETDIR register defines the direction of the
cam_global_reset signal.
•
The external generated cam_global_reset is used as a trigger when
[31] GRESETDIR =
0 and
[27:28] INSEL = 3.
•
The internally generated cam_global_reset is used as a trigger when
[31] GRESETDIR
= 1 and
[27:28] INSEL = 3.
•
If the PARALLEL interface is selected, control-signal generation works for both ITU and SYNC modes
1189
SWPU177N – December 2009 – Revised November 2010
Camera Image Signal Processor
Copyright © 2009–2010, Texas Instruments Incorporated