CS6150 Amphion Semiconductor Ltd., CS6150 Datasheet - Page 9

• Manufacturer Part Number: CS6150
• Description: Motion JPEG Decoder
• Manufacturer: Amphion Semiconductor Ltd.

Table 4: Status Register Pin Definition
The status register flags (DecFlags[7:0]) indicate the current
state of the CS6150 operation. When an error is detected during
the coding process, the compression process is suspended
and the CS6150 waits until a reset process is invoked by
The decoding parameter bus (PValue[15:0]) is a 16-bit port
used to output various parameters extracted from the input
data stream and currently used by the core. The 4-bit selector
input (PType[3:0]) determines which internal parameters are
displayed on the parameter bus as per Table 5.
STATUS AND CONTROL
BIT
7
6
5
4
3
2
1
0
DecHfError
IDctInProg
DecInProg
JpgInProg
DecError
CtlError
NAME
QtError
HtError
Set when an undefined Huffman table symbol is referenced during decoding
Set when an invalid SOF parameter is detected
This includes detecting:
Set when an invalid SOS parameter is detected
This includes detecting:
Set when DecFlags[7] is set
Set when there is a mismatch between the DNL segment input to the core and the number of lines in the input
image which have already been decoded
Set when an invalid DHT segment is detected
This includes detecting:
Set when an invalid DQT segment is detected
This includes detecting:
Set when anything other than a JPEG marker is input
Set when any of DecFlags[7:4] are set
Set when any SOF marker is detected other than SOF0
Set if incomplete Huffman or quantization definition is detected
Set when the first sample of the first 8x8 block is output from the core and de-asserted when
the last pixel of last block of the image is output
For each scan this signal is asserted after the SigSOS signal has been output from the core and is de-asserted
when the decoding of a scan is complete. It indicates that the core is in the decoding state
Set when core starts to process input data (JpgIn) and de-asserted when decoding has been completed i.e.
when the last pixel of last block of the image is output
• A sample precision which is not equal to 8-bit
• The horizontal size of the image set to zero
• The number of components in a frame set to zero
• Any of the horizontal or vertical sampling ratios set to be greater than 4
• The quantization table ID greater than 3
• A reference to an undefined Huffman or quantization table
• The number of components in a scan to be zero or more than 4
• More than 10 blocks in an MCU
• Incorrect SOS fixed parameter settings (these should be as follows:Ss=0 Se=63 AhAl=0)
• An all one Huffman code
• An invalid Huffman Table class (this should be ‘0’ for DC tables and ‘1’ for AC tables)
• An invalid Huffman table identifier (this should be in the range 0 to 3)
• The L value limit has been exceeded (this should be 12 for a DC table and 162 for an AC DC table)
• A zero quantization coefficient
• An invalid quantization level precision (this should be set to zero for baseline JPEG)
• An invalid quantization table identifier (this should be in range 0 to 3)
DECODING PARAMETER BUS
STATUS REGISTERS
The data available on the PValue port does not contain con-
trol signals used by the CS6150. Many of the values however
can be used to control other logic instantiated around the
CS6150, i.e. the FX and FY parameters (PType 0x0 and 0x1)
could be used to control a raster to block converter.
signal RSTn or CLR. The individual bits are set to zero at
reset and active high to indicate an error condition as defined
in Table 4:
DESCRIPTION
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