DAC1008D750HN NXP [NXP Semiconductors], DAC1008D750HN Datasheet - Page 15

• Manufacturer Part Number: DAC1008D750HN
• Manufacturer: NXP [NXP Semiconductors]

NXP Semiconductors
DAC1008D750
Product data sheet
10.2.3 Comma detection and word align
The lane processing makes use of the sync patterns to synchronize the datastream,
determine the initial running disparity and extract the 10-bit word from the incoming
datastream (word-alignment).
The SYNC_OUT signal is also used during normal operation by the DAC1008D750 to
request a link reinitialization. This occurs when the 10b/8b module loses synchronization.
The SYNC_OUT signal conforms to LVDS signaling. Its common-mode voltage and its
single-ended peak amplitude can be programmed using SET_SYNC_LEVEL bits in the
SET_SYNC registers (see
SYNC_OUT is asynchronous with the frame clock. There is no timing specification with
respect to the CLKINP and CLKINN inputs.
This stage monitors the datastream for code characters (Comma detection), decodes the
words to bytes (octets) and performs optional character replacement as part of frame/lane
alignment monitoring and correction. This module provides the required control signals to
the RX-controller and ILA.
This module decodes the 10-bit words into 8-bit words (octets). The decoding table is
specified in the IEEE 802.3-2005 specification. During decoding, the disparity is
calculated according to the disparity rules mentioned in the same specification
IEEE 802.3-2005. When the disparity counter is more than +2 or less than −2, an error will
be generated.
The following comma symbols are detected during data transmission irrespective of the
running disparity:
The following flags are also triggered according to the following definitions:
DAC1008D750 supports character replacement whatever the state of the descrambler.
When scrambling is not active, the received K28.3 /A/ or K28.7 /F/ will be replaced by the
previous sample. When scrambling is active, the corresponding data octet D28.3 (0xC) or
D28.7 (0xFC) will be used.
A flag is sent to the control interface to reflect detected commas in registers.
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•
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VALID: a code group that is found in the column of the 10b/8b decoding tables
according to the current running disparity.
DISPARITY ERROR: The received code group exists in the 10b/8b decoding table,
but is not found in the proper column according to the current running disparity.
NOT-IN-TABLE (NIT) ERROR: The received code group is not found in the 10b/8b
decoding table for either disparity.
INVALID: a code group that either shows a disparity error or that does not exist in the
10b/8b decoding table.
/K/ = K28.5
/F/ = K28.7
/A/ = K28.3
/R/ = K28.0
/Q/ = K28.4
All information provided in this document is subject to legal disclaimers.
Rev. 2 — 5 January 2011
Table 77 on page
2×, 4× or 8× interpolating DAC with JESD204A
56).
DAC1008D750
© NXP B.V. 2011. All rights reserved.
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