- SS-HQ1 Application Notes -
Ver.1.0.0 January 7, 2005
99
10.4. Variable
Gamma
Function
10.4.1. Gamma Curve Types
Fig 10.4-1 Gamma Curve Selection
The SS-HQ1 system’s DSP (CXD3172AR) has an internal gamma correction circuit. The parameter GAMSEL
(CAT12_Byte7_bit0) can be used to switch between User Gamma 0, which is saved to EEPROM for use, and
User Gamma 1, which can be changed at immediately through serial communication. Use either of these two
values according to the particular application.
Table 10.4-1 Gamma Curve Selection Parameter
Parameter Name
Description
Setting Value
Applications
0[h] : User Gamma 0
(value saved in
EEPROM)
A fixed, such as a factory default
setting.
The category 2 parameter is
saved to EEPROM for use.
GAMSEL
(CAT12_Byte7_bit0)
Gamma curve selection
1[h] : User Gamma 1
(value set through
serial communication)
A temporary curve change, used
for applications such as camera
installation adjustment (portable
monitor) or matching to a
user-provided monitor.
The value set in the category 13
parameter can be changed simply
through serial communication.
Note
Under the default setting (initial setting with no EEPROM), GAMSEL is set to input through port P11 (pin 79).
INPUT
EEPROM
PC
USER_GAMMA_0
INPUT
OUT
P
UT
GAMSEL= 0
GAMSEL= 1
or
Ext_micom
Communication
Initializing
OUT
P
UT
USER_GAMMA_1