2/24/2008 9T6WP
Preliminary Hardware Data Module
BCM7405
06/29/07
Functional Description
Bro a d c o m Co rp o r a ti o n
Document
7405-1HDM00-R
Video and Graphics Display Page 1-49
ROP Architecture
The ROP is the final stage of the compositor function. This allows a logical combination of operators to be applied to the
output data. The ROP is realized in hardware by using an 8 to 1 multiplexor. The control signals are tied to the various inputs
while the data inputs are tied to a programmed register. This allows the inputs to select a programmed value for display
purposes. Common uses of the ROP function are to handle screen-door blends and fades.
Software has to handle any initial offset in the 8 x 8 bit map registers. This can be accomplished by simply reloading the
registers with the new bit map.
Capture Architecture
The capture module is responsible for accessing memory to store the modified graphics or video data. It is responsible for
any format conversion and addressing control.
The output formats supported are as follows:
•
32-bit formats
-
AYCrCb_8888
-
YCrCbA_8888
-
ARGB_8888
-
RGBA_8888
•
16-bit formats
-
RGB_565
-
WRGB_1555
-
RGBW_5551
-
ARGB_4444
-
RGBA_4444
•Y0CrY1Cb_8888
•Y1CrY0Cb_8888
•Y0CbY1Cr_8888
•Y1CbY0Cr_8888
•CrY1CbY0_8888
•CrY0CbY1_8888
•CbY1CrY0_8888
•CbY0CrY1_8888
•
8-bit format
-
P_8
-
A_8
•
Other formats
-
P_4
-
P_2
-
P_1
-
P_0
-
A_4
-
A_2
-
A_1