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Internal Modules
243
SPRUHI7A – December 2012 – Revised June 2016
Copyright © 2012–2016, Texas Instruments Incorporated
High-Definition Video Processing Subsystem (HDVPSS)
1.2.13.3.1.5.1.2 Frame Height
Bits 15:0 indicate the height in pixels of the entire frame. This is the height of the entire frame and not just
the height of the data represented by the current channel unless this channel fills the entire frame. This
allows for the VPDMA to present a larger frame of data to the client while only fetching the required data.
The currently supported maximum height is 2048.
1.2.13.3.1.5.2 Outbound data
Table 1-79. Data Packet Descriptor Word 4 Outbound Data Field Descriptions
Bits
Name
Description
31-5
Descriptor Write Address
The 32 byte aligned location to write an
inbound descriptor
2
Write Descriptor
If set to 1, a descriptor will be generated
when the client completes a frame.
1
Drop Data
If set to 1, the data will not be written out.
Also, if this is set, the write descriptor bit
MUST be set.This allows for descriptors to
only be written out so that software can
determine the size of the required buffer
before data is written out.
0
Use Descriptor Register
If set to 1, the CURRENT_DESCRIPTOR
register will be used for the write address
location. If set to 0, the Descriptor Write
Address field in this word will be used for
the Descriptor Write Address.
1.2.13.3.1.5.2.1 Descriptor Write Address
Bits 31:5 set the 32 byte address to write the generated descriptor. This address is only used if the Write
Descriptor bit is set to 1 and the Use Descriptor Register bit is set to 0. If this case is met when the
channel is complete a descriptor that meets the inbound descriptor format will be written to the location
specified by this field. This allows for software to have a specific channel write its descriptor to a specific
address no matter what order the channel completes compared to other outbound channels.
1.2.13.3.1.5.2.2 Write Descriptor
Bit 2 determines if a descriptor should be written out when the client is completed. If this bit is set the
descriptor will be written. The format of the descriptor will be of an Inbound Data Transfer descriptor with
the LINE LENGTH and TRANSFER HEIGHT fields determined by the counters in the clients. This means
that the direction bit will be the opposite of the inbound descriptor. The FRAME WIDTH and FRAME
HEIGHT values will match the LINE LENGTH and TRANSFER HEIGHT fields. The CHANNEL and NEXT
CHANNEL fields will match the NEXT CHANNEL field of the original descriptor. The FIELD bit will match
the source field captured by the client. The NOTIFY bit will always be 0. All other fields will match the
original outbound descriptor. If the Outbound descriptor MODE is set to TILED data then the descriptor
address used will be in TILED data space and software must ensure that the address is in page mode for
the address of the descriptor.
1.2.13.3.1.5.2.3 Drop Data
Bit 1 determines if the data should be written out or not. In some cases software might only want to write
the descriptor out to determine the size of the buffer that will be required to store incoming data. By setting
this bit,no data will be written out. If this bit is set then the Write Descriptor bit MUST be set.
1.2.13.3.1.5.2.4 Use Descriptor Register
Bit 0 determines where the descriptor should be written. This bit MUST be set to 0.