set_max_delay / set_min_delay & set_output_delay query
I tried constraining the following using set_max_delay & set_min_delay flash_nce output port :
set PERIOD_CLK 100.000
create_clock -name {clk} -period $PERIOD_CLK -waveform { 0.000 50.000 } [get_ports {in_clk}]
create_clock -name {clk_virt} -period $PERIOD_CLK -waveform { 0.000 50.000 }
set_max_delay -from [get_ports {in_clk}] -to [get_ports flash_nce] 70
set_min_delay -from [get_ports {in_clk}] -to [get_ports flash_nce] 50
Note: Suggestion in one of the PFL documents was to constrain eg flash_nce using set_max_delay. Had to also add set_min_delay constraint because it was reported as partially constrained.
However, STA (Static Timing Analyzer) tool still reported 'unconstrained output port within unconstrained paths/summary section.
Had to add the following too to resolve the 'no output constraint on flash_nce' :
set output_max 70.0
set output_min 50.0
set_output_delay -clock clk_virt \
-max $output_max \
[get_ports flash_nce]
set_output_delay -clock clk_virt \
-min $output_min \
[get_ports flash_nce]
--
Same with the following constraint :
create_generated_clock -name dclk1 -source [get_ports in_clk] -divide_by 1 -invert [get_ports fpga_dclk]
It still reported 'No output delay was set on output fpga_dclk port. This port has clock assignments'
Can I ignore this warning ?
Please comment here.