Altera Stratix GX Transceiver - Manual (Page 108)

4–26 Altera Corporation
Stratix GX Transceiver User Guide January 2005
SONET Mode MegaWizard Plug-In Manager
Figure 4–19. MegaWizard Plug-In Manager - ALTGXB (Page 5 of 9) - Receiver (1) Notes (1) – (5)
Notes to Figure 4–19 :
(1) For more information, refer to the Stratix GX Analog Description chapter.
(2) The rx_enacdet port lets the word aligner byte align to the word alignment pattern (active high synchronous
signal). The signal must go low then high to trigger word re-alignment. If this option is de-selected, the word aligner
is not active, but the pattern detect signal is still functional.
(3) Manual bit-slipping mode lets you control the word aligner’s shift register directly via the rx_bitslip port. A
low-to-high transition on rx_bitslip port enables the word aligner’s shift register to slip one bit. For example, if
a 3-bit shift is required to align the incoming byte, rx_bitslip must be toggled low, high, low, high, low, and high.
The rx_bitslip can be left in the high or low position after the above sequence.
(4) The word alignment pattern size in SONET mode is always set to 16-bits, and the pattern must be set to
1111011000101000 (F628) if “flip word alignment pattern bits” is set or 0001010001101111 (146F) otherwise, regardless
of whether the incoming pattern is an A1/A2 or A1/A1/A2/A2.
(5) Flips the word alignment bit order. If checked, the rightmost bit is the MSB, otherwise the rightmost bit is the LSB.
Used in conjunction with receiver and transmitter bit flip options to ensure that the MSB is transmitted and received
first in the serial stream.