Virtex® Family FPGAs

[med]

Hi,

 when I try to use the output of Oddr bloc as input to another component, the following error appears:

ERROR:Pack:2530 - The dual data rate register "DDR/ODDR_inst" failed to join an
   OLOGIC component as required.

What should I do so that I can use the output of Oddr as input for another component?

can someone help me please

[gszakacs]

ODDR is an "Output" double-data-rate register.  As the name implies this can ONLY be used

as an output from the FPGA.  Any component downstream from this will therefore not be in

your design, but rather off-chip - like a DDR memory device.  The ONLY component you can

drive with the output of the ODDR is an OBUF or OBUFDS.

Perhaps if you describe what you are trying to do with this register we can help you find another

solution.

Regards,

Gabor

[med]

In fact, I have to send two signals: a signal 'D' for data and a signal S '(with a simple XOR between the clock signal and the'D') hence the need to use output 'D' (which is the output of block Oddr)

[mcgett]

> In fact, I have to send two signals: a signal 'D' for data and a signal S '(with a simple XOR between

> the clock signal and the'D') hence the need to use output 'D' (which is the output of block Oddr)

First, the only connection that the output of the ODDR can make is to an output buffer it cannot be used in any other way.

Second, this doesn't make sense.

You have instantiated an ODDR register that has two data bits connected to D1 and D2 and clocked by your CLOCK net. I can't conceive of why you would need to XOR the output with the same CLOCK net that is driving it to create your "S" signal.

Since D1 will be clocked out on the rising edge of the CLOCK net an XOR with the value would simply by !D1.

Since D2 will be clocked out on the falling edge of the CLOCK net an XOR with the value would simply by D2.

So, if you really need this then add another ODDR with an inverted D1.

[kanwal_]

how to instantiate a ODDR block in my verilog code to remove error 1203 ?,,, plz urgently give me the ans

[eteam00]

Kanwal,

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