Intel® Quartus® Prime Timing Analyzer Cookbook

ID 683081
Date 11/12/2018
Public

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System Synchronous Output

The following figure shows a typical chip-to-chip output interface and the various parameters necessary to specify an output delay for the interface.
Figure 13. Simple Chip-to-Chip Interface

System Synchronous Output Constraints

#specify the maximum external clock delay to the FPGA set CLKs_max 0.200 #specify the minimum external clock delay to the FPGA set CLKs_min 0.100 #specify the maximum external clock delay to the external device set CLKd_max 0.200 #specify the minimum external clock delay to the external device set CLKd_min 0.100 #specify the maximum setup time of the external device set tSU 0.125 #specify the minimum setup time of the external device set tH 0.100 #specify the maximum board delay set BD_max 0.180 #specify the minimum board delay set BD_min 0.120 #create a clock 10ns create_clock -period 10 -name sys_clk [get_ports sys_clk] #create the associated virtual input clock create_clock -period 10 -name virt_sys_clk #create the output maximum delay for the data output from the FPGA that #accounts for all delays specified set_output_delay -clock virt_sys_clk \ -max [expr $CLKs_max + $BD_max + $tSU - $CLKd_min] \ [get_ports {data_out[*]}] #create the output minimum delay for the data output from the FPGA that #accounts for all delays specified set_output_delay -clock virt_sys_clk \ -min [expr $CLKs_min + $BD_min - $tH - $CLKd_max] \ [get_ports {data_out[*]}]