Texas Instruments OMAP36 Series, Техническое справочное руководство

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Start configuration of
VRFB context i
Page size definition
Start
End
Page width in bytes: Set the
SMS_ROT_CONTROLi[6:4] PW field.
Page height in bytes: Set the
SMS_ROT_CONTROLi[10:8] PH field.
The power of two is used to
indicate the width and height
(Example: width = 32 = 2^5,
thus PW = 5)
Definition of the
image parameters
(before rotation)
Start
Image width in pixels: Set the
SMS_ROT_SIZEi[10:0] IMAGEWIDTH field.
Image height in pixels: Set the
SMS_ROT_SIZEi[26:16] IMAGEHEIGHT field.
Pixel format in bytes: Set the
SMS_ROT_CONTROLi[1:0] PS field.
End
YUV standard usage:
The image width must be set to one-
half the number of pixels per row,
because the YUV pixel data is spread
onto a 32-bit word representing 2
pixels.
YUV standard usage:
The pixel format must be set to
4 bytes, because the YUV pixel data
Is spread onto a 32-bit word
representing 2 pixels.
Is the programmed
image size bigger than
the actual image
Initiator programs its DMA engine:
an additional offset to the base
address may be required.
Yes
Indicate the physical base address of the
picture in SDRAM.
Set the SMS_ROT_PHYSICAL_BAi[30:0]
PHYSICALBA field.
No
End configuration of
VRFB context i
Once the VRFB context has been configured,
all image data can be accessed through the
VRFB virtual address space: address
translation is automatic.
sdrc-021
size?
Public Version
SDRAM Controller (SDRC) Subsystem
www.ti.com
Figure 10-64. VRFB Context Configuration
Figure 10-65 is an example of VRFB context configuration using both RGB and YUV image formats. This
example represents the configuration of a 1024-byte page size (32 * 32 byte page) and a 240 * 240 image
size using VRFB context 1.
2280 Memory Subsystem SWPU177N – December 2009 – Revised November 2010
Copyright © 2009–2010, Texas Instruments Incorporated