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Altera_Forum
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13 years ago

Synchronizing TXCVR & RXCVR

Hello: If the interface between the FPGA fabric and the TX module is a 16-bit bus and the RX is 16 bit bus to the Fabric, is there a good way to synchronize so the RXCVR can detect a speci...
Altera_Forum's avatar
Altera_Forum
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13 years ago

Hi Dave:

I have read the TXCVR spec byte ordering section but still have some questions.

One thing I don't understand is the 9-bit pattern. Why is it 9-bits and not 10?

As an example, using the 8B/10B encoder on the RXCVR portion of the ALTGX configuration the default value for the ordering pattern is b'111111011 (is this a K word?). Does the pattern need to be code word to differentiate from data?

My interface to the TXCVR parallel connection to the fabric is 16-bits.

How does this pattern b'111111011 translates to the pattern that I need to send on the parallel interface, Tx_datain[15..8]= ????, Tx_datain[7..0]= ????

The ALTGX will provide a signal rx_byteorderalignstatus to indicate when the pattern was found. The configuration also provides a pad pattern, should we use this pattern for anything (we already have the signal rx_byteorderalignstatus)? I am wondering why this is user configurable.

thanks again