MOTOROLA
Chapter 3. Receiver
3-15
Receiver Functional Description
the error reported if multiple errors occur at the same time. The lower the Priority numbered
errors are reported first.
3.3.7
Receiver Interface Clock Timing Modes
The receiver interface is double data rate, source synchronous. Each of the receiver’s eleven
output signals (eleven for byte interface and twelve for ten-bit interface) are timed relative
to the rising and falling edges of the receiver interface clock output, RECV_x_CLK. The
receiver interface clock frequency may be selected between its own recovered clock
frequency, receiver A’s recovered clock frequency, or the frequency of the reference clock
input(s) REF_CLK_P / REF_CLK_N.
The recovered clock enable signal, RCCE, determines if the receiver interface is timed to
the recovered clock or to the local reference clock. Asserting RCCE enables timing relative
to the recovered clock, and set low enables timing relative to the reference clock. When
Table 3-3. Receiver Interface Error Codes (Byte Interface)
RECV_x_ERR RECV_x_K RECV_x_IDLE
Priority
Description
Low
8
Normal operation, valid data character received.
Low
High
3
Overrun / Underrun: The receiver interface
synchronization logic detected an overrun/underrun
condition. Data may be dropped or repeated.
Low
High
Low
7
Normal operation, valid control character received.
Low
High
6
Normal operation, valid Idle (K28.5) character received.
High
Low
4
Code Error: The 8B/10B decoder detected an illegal
character.
High
Low
High
5
Disparity Error: The 8B/10B decoder detected a disparity
error.
High
Low
1
Not Byte Sync: The receiver is in start-up or has lost byte
alignment and is searching for alignment.
High
2
Not Word Sync: The receiver is byte synchronized but has
not achieved or has lost word alignment and is searching
for alignment.
Table 3-4. Receiver Interface Error Codes (Ten-Bit Interface)
RECV_x_ERR RECV_x_IDLE
Priority
Description
Low
4
Normal operation, non-Idle character received.
Low
High
3
Normal operation, Idle (K28.5) character received.
High
Low
1
Not Byte/Word Sync: The receiver is in start-up or has lost byte or
word alignment and is searching for alignment.
High
2
Overrun/Underrun: The receiver interface synchronization logic
detected and overrun/underrun condition. Data may be dropped or
repeated.
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Freescale Semiconductor, Inc.
For More Information On This Product,
Go to: www.freescale.com
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