About Transceiver???

Hi, I'm back!

I read the stratix handbook recently carefully. I found the transceiver really can recover 1Gbps input data with maybe 50MHz refclk.

I don't know wethear you are really understand what burst-mode data is. It's common in OBS(optical burst swithing) net. General speaking, the input data may contain two or more kinds of data stream whose rate is nearly 1Gbps but not the same for each other.

For example, there are 9000 bits in the input data stream. The rate of the 1--3000 bits is 1.0001Gbps, The rate of the 3001--6000 bits is 1.0000Gbps, The rate of the 6001--9000 bits is 0.9999Gbps. At first, I can get the 1GHz cruclk from refclk by the transceiver in the lock-to-refclk mode accurately, after at least 15us(the handbook said), the transceiver turns into lock-to-data mode.

If it lock the frequecy & phase of the first 3000 bits data and recover them successfully, can the CRU will recover the middle 3000 bits data accurately at once, not need to go back to the lock-to-refclk and then turn into lock-to-data to recover the middle 3000 bits data?

From theory, I think the CRU will recover the middle 3000 bits data at once. Because of the two sigals(up & down), I think them can tune the PFD to make the VCO always locking the input data automaticly. But wether the auto-fit speed of the VCO is fast enough to recover the burst-mode data in fact, I'm not sure.

So could Kaz or anybody else who have the expericen to recover the burst-mode with transceiver give me help and answer? Thanks a lot!!