ch5001a ETC-unknow, ch5001a Datasheet - Page 26

• Manufacturer Part Number: ch5001a
• Description: Cmos Color Digital Video Camera
• Manufacturer: ETC-unknow

CHRONTEL
Programmable Sample and Hold Gain Register
Register PSHG specifies the gain of the programmable sample and hold before A/D conversion. There are eight gain
settings ranging from a gain of 1.5x to a gain of 5.0x. When the autoshutter algorithm is controlling the gain value
and this register is read out, the autoshutter generated gain value is read instead of the actual IIC register content.
Bits 5 and 4 (GAM[1:0]) control the gamma correction used, according to Table 11.
Clamp Level Register
Register BCLMP specifies the offset level used in the black level clamp block.
A value of 0 in register BCLMP will nominally cause the A/D to output a value of zero for a dark cell input. The
register value is 2’s complement and ranges from -128 at maximum brightness to +127 at minimum brigtness. This
register has no effect when the ASBE bit is HIGH (default).
Miscellaneous Register
Bits 0 and 1 of the MISC register control the border color that is output on each line containing active video for eight
13.5MHz clocks before the start of active video and eight 13.5MHz clocks after active video. This is only done
when the IC is placed into display modes four or five (M[2:0] = 4,5). In these modes, the luminance data has been
interpolated to a pixel rate of 13.5MHz. Therefore, 8 pixels equals 592.5nS. The border colors are described in
Table 12.
26
Table 11. Gamma Correction
BIT:
SYMBOL:
TYPE:
DEFAULT:
BIT:
SYMBOL:
TYPE:
DEFAULT:
BIT:
SYMBOL:
TYPE:
DEFAULT:
GAM1
0
0
1
1
Reserved
Reserved
BCLMP7
R/W
R/W
R/W
7
7
0
1
7
1
GAM0
0
1
0
1
Reserved
Reserved
BCLMP6
R/W
R/W
R/W
6
6
6
0
0
0
Gamma
1.0
1.6
2.2
2.2
Reserved
BCLMP5
GAM1
R/W
R/W
R/W
5
5
0
5
0
0
BCLMP4
PUD4*
GAM0
R/W
R/W
R/W
PD
4
1
4
0
4
Reserved
BCLMP3
R/W
VSP
R/W
R/W
3
1
3
3
0
0
BCLMP2
PSHG2
HSP
R/W
R/W
R/W
2
0
2
0
2
0
201-0000-032 Rev 3.0, 6/2/99
Symbol: PSHG
Address:17h
Bits:8
Symbol:BCLMP
Address:18h
Bits:5
Symbol:MISC
Address:19h
Bits:7
BCLMP1
PSHG1
BDR1
R/W
R/W
R/W
1
0
1
0
1
0
CH5001A
BCLMP0
PSHG0
BDR0
R/W
R/W
R/W
0
1
0
0
0
0