Xilinx LogiCORE IP Spartan-6 Getting Started Manual page 28

Chapter 3: Running the Wizard
Table 3-10: Comma Detection
Option
Use Comma Detection
Decode Valid Comma Only
Comma Value
Plus Comma
Minus Comma
Comma Mask
Any Byte Boundary
Align to...
Even Byte Boundaries
Table 3-11
Table 3-11: Optional Ports
Option
Active-High signal which enables the byte boundary alignment process when Plus Comma
ENPCOMMAALIGN
pattern is detected.
Active-High signal which enables the byte boundary alignment process when Minus Comma
ENMCOMMAALIGN
pattern is detected.
Active-High signal that causes the byte alignment to be adjusted by one bit with each assertion.
RXSLIDE
Takes precedence over normal comma alignment.
RXBYTEISALIGNED Active-High signal indicating that the parallel data stream is aligned to byte boundaries.
Active-High signal indicating that byte alignment has changed with a recent comma detection.
RXBYTEREALIGN
Note that data errors can occur with this condition.
Active-High signal indicating the comma alignment logic has detected a comma pattern in the
RXCOMMADET
data stream.
28
Enables receive comma detection. Used to identify special protocol comma and
framing characters in the data stream.
When receive comma detection is enabled, limits the detection to specific defined
comma characters.
Select one of several standard comma patterns or User Defined to enter a custom
pattern.
The PCI EXPRESS example is K28.5.
10-bit binary pattern representing the positive-disparity comma character to
match. The right-most bit of the pattern is the first bit to arrive serially.
The PCI EXPRESS example uses 0101111100.
10-bit binary pattern representing the negative-disparity comma character to
match. The right-most bit of the pattern is the first bit to arrive serially.
The PCI EXPRESS example uses 1010000011.
10-bit binary pattern representing the mask for the comma match patterns. A 1
bit indicates the corresponding bit in the comma patterns is to be matched. A 0
bit indicates don't care for the corresponding bit in the comma patterns.
The PCI EXPRESS example matches all ten bits (1111111111).
When a comma is detected, the data stream is aligned using the comma pattern
to the nearest byte boundary.
When a comma is detected, the data stream is aligned using the comma pattern
to the nearest even byte boundary. This option is available only for 16 and 20 bit
RX data interfaces.
shows the optional ports available on this page.
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Description
Description
Spartan-6 FPGA GTP Transceiver Wizard v1.8
UG546 (v1.8) December 14, 2010