xilinx spartan 6 deserialization

[Serkan]

I just have 1 fast LVDS data line. I need to have 10 bits of data
in a register , every 5 clock cycles(DDR), coming from only 1
differential data line.

Dear Gurus,

1- Can I deserialize a 240 Mhz , LVDS, DDR input coming data using a
10:1 serdes ratio. (clk is also LVDS)
2- I want to do it with data width = 1( D = 1), is it possible?
3- Do I have to put delay to clk inputs. If not why is there a delay
element (IODELAY2) in xapp1064.pdf
4- Do I have to use the pll concept. Is there any other solution?
5- In the documentation of spartan 6 deserialization 16:1 is shown
but with a SDR rate. Can it be changed to DDR?


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PS1: I am using Spartan 6, slx100, -3
PS2: I checked xapp1064.pdf, ug381.pdf, ds162.pdf. I need more info
on IODELAY2 and ISERDES2.


best regards
Serkan

 

[Lorenz Kolb]

Serkan wrote:

I just have 1 fast LVDS data line. I need to have 10 bits of data
in a register , every 5 clock cycles(DDR), coming from only 1
differential data line.

Dear Gurus,

1- Can I deserialize a 240 Mhz , LVDS, DDR input coming data using a
10:1 serdes ratio. (clk is also LVDS)

240 MHz shouldn't be a problem for the Spartan 6 pins.

2- I want to do it with data width = 1( D = 1), is it possible?

What's your question? Input or Output datawidth?
From my understanding you want a 1 bit input (240 MBit/s) deserialized
to 10 bit (@24 MBit/s) output, right?
Don't see any reason why this shouldn't work.

3- Do I have to put delay to clk inputs. If not why is there a delay
element (IODELAY2) in xapp1064.pdf

What's the protocol you use for clock recovery/synchronization?

4- Do I have to use the pll concept. Is there any other solution?

Have a look at
http://www.missinglinkelectronics.com/files/papers/MLE-TB20091127.pdf
and XAPP224 respectively.
You will need some reference clock, and you will have to use a PLL or
DCM somewhere in the system, to generate the right clock(s) from that
reference.

5- In the documentation of spartan 6 deserialization 16:1 is shown
but with a SDR rate. Can it be changed to DDR?

So again: what's the point here? I still don't get what you are trying
to do, but you might also be interested in XAPP460,

Lorenz