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BG0836 1/2.7 inch 1080P HD CMOS image sensor
Name
ROWTIME_
H
ROWTIME_L
VBLANK_H
VBLANK_L
Adjust the exposure and gain
Adjust the exposure
In the figure below，��
between vsync and the first image data. ��
between the last image data and invalid vsync. VBLANK and ROWTIME is the name
of BG0836 registers, their relationship as follows：
Tfrm = Tbp + Tfp + ( VSIZE + VBLANK ) ∗ ROWTIME ∗ Tmclk
Combined, the frame time formula is:
Tfrm = ( 8 + VSIZE + VBLANK ) ∗ ROWTIME ∗ Tmclk
Registers which control the
vertical blanking
（
）,
Table 14 Frame rate control register
Address
0x000e
0x000f
0x0021
0x0022
The default value of ROWTIME is 0x12C4（4808）, the default value of VBLANK is
0x0024, according to the above formula， frame time is：
ROWTIME and VBLANK registers are written, 0x001d register need to write 0x01
or 0x02.
The register TEXP and the register TEXP_MCK control exposure time. TEXP is as
row time as a unit，TEXP_MCK is as main clock as a unit. Formula for calculating
exposure time as follow：
Texp = (TEXP ∗ ROWTIME + TEXP_MCK) ∗ Tmclk
Where ROWTIME is the register name. Please refer to the section "adjust the output
frame rate". Texp must be smaller than Tfrm, otherwise you can't output image. TEXP
and TEXP_MCK register address is as shown in the table below:
is the frame time. ��
������
Tbp + Tfp = 8 ∗ ROWTIME ∗ Tmclk
output frame rate is
the address is shown below
Width
8
Bit[15:8]
registers(main clock unit)
8
Bit[7:0]
registers(main clock unit)
8
Bit[15:8] of Vertical blanking control
registers(row time unit)
8
Bit[7:0] of Vertical blanking control
registers(row time unit)
Tfrm = ( 8 + 1080 + 36 ) ∗ 4808 ∗ Tmclk
18/ 24
is called porch back, it means time
����
is called front porch, it means time
����
ROWTIME（line time）and VBLANK
：
Function
of
Row
time
control
of
Row
time
control
V1.2
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