Samsung S5PC100, User Manual

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S5PC100 USER’S MANUAL (REV1.0) CAMERA INTERFACE
9.3
-11
7.3 FRAME MEMORY HIERARCHY
Frame memories consist of four ping-pong memories for output DMA ports. Ping-pong memories have three
element memories that are luminance Y, chrominance Cb, and chrominance Cr. It is recommended that the
arbitration priority of CAMIF must be higher than any other masters except LCD controller. It is strongly
recommended that CAMIF priorities should be the fixed priorities, not rotation priorities. In multi-AHB bus case,
the priority of system bus including CAMIF must be higher than others. If bus is traffic enough that DMA operation
is not ending during one horizontal period plus blank, it might mal-function. Therefore, the priority of CAMIF must
be separated to other round robin or circular arbitration priorities. It is recommended that bus which includes
CAMIF, should have higher priority than any other buses in memory matrix system. The CAMIF should not be the
default master of AMBA system
Address Y1 / RGB1
Address Cb1
Address Cr1
Address Y2 / RGB2
Address Cb2
Address Cr2
Address Y3 / RGB3
Address Cb3
Address Cr3
Address Y4 / RGB4
Address Cb 4
Address Cr 4
4-pingpong
Frame memory
(SDRAM)
Image
Data
Camera Interface
Bus &
Memorycontroller
Figure 9.3-10 Ping-pong Memory Hierarchy