AV PCI CONTROLLER
13.20 JPEG Mode and Control
This register contains the JPEG Mode configuration and optional
control bits.
Address Offset: 0x100
Bit Type Mod
Description
31 RW all JPG- JPEG/MPEG mode selection. This bit
selects between the two code DMA controller
modes.
‘1’ - JPEG Mode.
‘0’ - MPEG Mode.
Default value is ‘0‘
30 : 29 RW
28 : 7 R
6
RW
5
RW
4
RW
jpg JPGMode - JPEG Sub-Modes Selection.
These two bits configure the JPEG sub-
mode.
11b - Motion Video Compression.
10b - Motion Video Decompression.
01b - Still Image Compression.
00b - Still Image Decompression.
Default value is 11b
Reserved. Returns zero.
jpg RTBSY_FB - RTBSY Feed-Back. Enables
the ZR36067 to de-assert the PXEN signal if
RTBSY is detected in the active area of the
field.
‘1’ - Enable PXEN de-assertion if RTBSY is
detected. Allowed only if SyncMstr=1.
‘0’ - Disable PXEN de-assertion.
Default value is ‘0’
Go_en - The enable bit of the ZR36060
START or ZR36050 GO command cycle. The
bit, when ‘1’, enables the GuestBus Master to
perform a JPEG START or GO cycle. During
a JPEG GO cycle the ZR36067 assumes that
the correct address (0x00h) is pre-latched in
an external address register. It is the host’s
responsibility to perform the write operation to
load the address. The host must de-assert
Go_en whenever it accesses the ZR36050
(using PostOffice) in a middle of a JPEG
process, or changes the address latched in
the external register. The host must also de-
assert Go_en before PostOffice pseudo
write-through burst cycles. In this case, the
host also has to wait at least 0.5 microsec-
onds before initiating the burst (to allow the
JPEG START or GO cycle to complete, if one
was started).
Default value is ‘0’ (Not enabled).
jpg SyncMstr - Sync Signals Master. This bit
configures the ZR36067 as a sync master.
This configuration is allowed in all JPEG
modes except Motion Video Compression
‘1’ - The ZR36067 is the sync signal master.
‘0’ - The sync signals are driven from an
external video source.
Default value is ‘0’
Address Offset: 0x100 (Continued)
Bit Type Mod
Description
3 RW jpg Fld_per_buff - Number of Fields Per Code
Buffer. This bit reflects the system memory
code buffer structure, in JPEG Compression
and Decompression modes.
‘1’ - The code buffer contains one code field.
‘0’ - The code buffer contains two consecutive
code fields, one code frame.
Default value is ‘0‘
2 RW jpg VFIFO_FB - VFIFO Feed-Back. Enables the
ZR36067 to de-assert the PXEN signal
according to the status of the Video FIFO.
‘1’ - Enable PXEN de-assertion if the pixel
buffer is close to overflow. Allowed only if
SyncMstr=1.
‘0’ - Disable PXEN de-assertion if the pixel
buffer is close to overflow.
Default value is ‘0’
1 RW jpg CFIFO_FB - CFIFO Feed-Back. Enables the
ZR36067 to de-assert the PXEN signal
according to the status of the Code FIFO.
‘1’ - Enable PXEN de-assertion if the code
buffer is close to overflow/underflow. Allowed
only if SyncMstr=1.
‘0’ - Disable PXEN de-assertion if the code
buffer is close to overflow/underflow.
Default value is ‘0’
0 RW jpg Still_LitEndian - Still image pixel Little
Endian format selector. This control bit
defines the pixel format in Still Image Com-
pression and Decompression.
‘1’ - The pixel format is Little Endian.
‘0’ - The pixel format is Gib Endian.
Default value is ‘1’.
13.21 JPEG Process Control
This register contains the JPEG process control.
Address Offset: 0x104
Bit
31: 8
7
Type
R
RW
Mod
all
Description
Reserved. Returns zero.
P_reset - Process Reset. This bit is asserted
by the host in order to reset the ZR36067
JPEG-related state machines. The bit must
be asserted at the beginning of a JPEG
process. While it is asserted, all of the JPEG
process parameters may be configured by
the host.
‘1’ - No reset.
‘0’ - Reset.
Default value is ‘1’.
6
R
5 RW
Reserved, Returns zero.
CodTrnsEn - JPEG Code Transfer Enable.
This bit enables the code transfer between
the internal code buffer and the system
memory in all of the JPEG modes.
‘1’ - Code transfer is enabled.
‘0’ - code transfer is disabled.
Default value is ‘0’.
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