Hello! I have little familiarity with the set_input_delay and set_output_delay SDC and was whether the following commands would correctly constrain the inputs. WHAT THE DIAGRAM SHOWS : I have an 8-bit port on a Video Decoder which outputs data to the FPGA.The clock used in the FPGA is output from the same device.The device is configured to change its data on the falling edge of the clock. The device opertes on a 27 Mhz clock i.e a period of 37.037 ns. The datasheet lists T5 as Output Hold Time and gives a minimum Value of 10ns. The datasheet lists T6 as Output Delay Time and gives a maximum Value of 25ns. So, I conclude that with respect to the falling edge of the clock, the data l begins to change 10ns after falling edge and regains stability 15ns later.Is this what the diagram depicts? If so, I think the constrains that specify this should be : create_clock -period 37.037 -name clkvin; #virtual clock for input constraint set_input_delay -clock clkvin -max 25 [get_ports sdr_data*] -clock_fall set_input_delay -clock clkvin -min 10 [get_ports sdr_data*] -clock_fall
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