ISE timing constraint

[Yannick]

Hi,

I need help for timing constraints in Xilinx virtex 4 Fx.

I have this design with two clocks on bufgmux and two components.

First clock : 50 Mhz
Second clock : 300 Mhz

Component A, need to work at 50Mhz
Component B, need to work at 300 Mhz

___________
| |
| |
|Component|
__________| A |
| | |
| |_________|
|
|\ |
CLK_50M ---| \ |
| \_________|
| / |
CLK_300M---| / |
|/ |
| ___________
| | |
|________| |
|Component|
| B |
|_________|

When I define both clock timing constraints on ucf file, ISE apply 300
Mhz for component A and B.
But the component A doesn't work at 300 Mhz and I don't whant that the
component A work at this frequency.

How i do for put the good frequency on each component whithout use two
bufg instead one bufgmux? (specific timing constraint)

Regards,

Yannick

 

[Symon]

Hi,

I need help for timing constraints in Xilinx virtex 4 Fx.

I have this design with two clocks on bufgmux and two components.

First clock : 50 Mhz
Second clock : 300 Mhz

Component A, need to work at 50Mhz
Component B, need to work at 300 Mhz

___________
| |
| |
|Component|
__________| A |
| | |
| |_________|
|
|\ |
CLK_50M ---| \ |
| \_________|
| / |
CLK_300M---| / |
|/ |
| ___________
| | |
|________| |
|Component|
| B |
|_________|

When I define both clock timing constraints on ucf file, ISE apply 300
Mhz for component A and B.
But the component A doesn't work at 300 Mhz and I don't whant that the
component A work at this frequency.

How i do for put the good frequency on each component whithout use two
bufg instead one bufgmux? (specific timing constraint)

Regards,

Yannick

Yannick,

1) You're posting on the wrong newsgroup. Next time try comp.arch.fpga .
2) You need to RTFM. Specifically, the contraints guide.
3) In the UCF do this:-

INST "component_a_name*" TNM="component_a_bits";
TIMESPEC TS1 = FROM : component_a_bits : TO : component_a_bits : 50ns;

INST "component_b_name*" TNM="component_b_bits";
TIMESPEC TS2 = FROM : component_b_bits : TO : component_b_bits : 50ns;

HTH, Syms.

 

[Symon]

I meant :-
TIMESPEC TS2 = FROM : component_b_bits : TO : component_b_bits : 3.3ns;