Specifications

74 Issue Date: 2004/11/05 │ CONFIDENTIAL
CL765 │ Camera Application Processor
Datasheet │ Doc. #: CLQP-DS-743
4.13.2.2. LCD Update under Camera Mode
1) LCD Lock
The CL765 has the overall control authority of the LCD when CL765 is
Camera mode, Therefore, the CL765 performs the displaying onto LCD once
it receives scaled Camera Data or encoding/decoding of the compressed
image. If MCU must access the LCD at this point, may use LCD LOCK
function to get override authority to access the LCD from the CL765. With
LCD Lock, CPU can directly access LCD under Camera Mode. LCD LOCK is
set by setting REG 0x3B to “0x01”. If LCD is not unlocked after setting LCD
Lock, the CL765 cannot display images on LCD. Therefore, CPU should
unlock LCD.
a) LCD Frame update interrupt check
If the CL765 perform LCD Lock while updating images on LCD, display
of one frame is stopped. To prevent this, the CL765 locks LCD after
“LCD Display End” interrupt has occurred. In not Preview, the process
to check the interrupt is not necessary.
b) LCD lock
Set REG 0x3b to 0x01.
c) LCD update
CPU directly updates LCD.
d) LCD unlock
Set REG 0x3B to 0x00.
e) If under Preview Mode, Preview is continuously performed.
a
bc d
: Camera Preview image update
: Ul Update Time 1
: Ul Update Time 2
a : Preview Update Interrupt
b : LCD Lock set
c : LCD Unlock set (Ul 1)
d : LCD Unlock set (Ul 1)
V_Blank V_Sync
C_Vsync
M_Intr
LCD_Access
Ul_Update1
Ul_Update2
Figure 4-24. LCD Lock during Camera Mode