create_clock -name clk_ddr -period 6 [get_ports DDR_CLK_OUT] set_output_delay -clock clk_ddr -max 2.1 [get_ports DDR_OUT] set_output_delay -clock clk_ddr -max 1.9 [get_ports DDR_OUT] -clock_fall -add_delay set_output_delay -clock clk_ddr -min 0.9 [get_ports DDR_OUT] set_...
-clock_fall :指明外部寄存器用该时钟的下降沿采样数据;常用于DDR接口 -add_delay:指明还有另一个外部寄存器与该端口相连;常用于DDR接口
set_input_delay -clock [get_clocks clk1] -clock_fall 1.0 [get_ports in] 结果如下,因为下降沿在6ns处,因为总的延时值为6ns+1ns共7ns 2.6Delay value already includes latencies of the specified clock edge Delay value already includes latencies of the specified clock用于设置延时值是否包含set_cloc...
输出约束对设计中的所有输出端口指定器件的所有外部延迟。 set_output_delay-clock{clock}-clock_fall-rise-max2foo 使用Set Output Delay(set_output_delay)约束指定外部输出延迟要求。指定Clock name(-clock)以引用虚拟或实际时钟。指定时钟时,时钟定义输出端口的锁存时钟。Timing Analyzer自动确定启动输出数据的器件内...
set_output_delay-clock{clock}-clock_fall-rise-max2foo Use theSet Output Delay(set_output_delay) constraint to specify external output delay requirements. Specify theClock name(-clock) to reference the virtual or actual clock. When specifying a clock, the clock defines the latching clock for th...
关于set_input/output_delay中的-clock_fall和-add_delay选项 2012-09-20 12:09 −... freshair_cn 0 2008 流(IO---Input、output) 2019-12-11 17:13 −一、都是站在程序的立场。从程序读数据源就是Input,从程序写入数据源,就是output。这个数据源可以是文件、图片、视频、内存、网络等;InputStream...
-clock 指定设置input delay的port是相对于哪个时钟设置的,即由port进入的signal信号是有哪个clock采样的,例如 组APB总线的信号,进入芯片内部采样时钟应该是APB clk。 -max/min 指定input delay的最大值和最小值,分别用于STA的setup check和hold check计算。 -clock_fall 如果外部时钟是下降沿发送数据,需要指定该参...
set_output_delay -clock dac_clk_a -min -0.65 -clock_fall -add_delay [get_ports *_Adata_out_p] Now the question is - which edges is the tool going to use for capture. By default, it is the "next edge". So the window at time 0.05 to 0.65, which...
set_output_delay -clock [get_clocks PJTAG_TCK] -clock_fall -min -add_delay -12.500 [get_ports PJTAG_tdo] #Add the next constraint to get rid off the partial output delay warning. set_output_delay -clock [get_clocks PJTAG_TCK] -clock_fall -max -add_delay 0.00 [get_ports PJTAG_...
One more question: in case the FPGA can't satisfy the set_output_delay constraint(e.g. fall short of the hold check), I can use the I/O buffer to slightly increase the delay, but as you explained such tweak must be within the margin since I am also affecting the setup...