Clock divider and CTS

Turbodebug check Design netlist about clk div timing path:

Fig. 1 Design/inst_clk_div

Fig. 2, 3 Design/inst_clk_div/inst_clk_div_mux/inst_mux_nand2/hic_dnt_nand2/ZN

Fig. 4 Design/inst_clk_div/inst_clk_div_dff/hic_dnt_out_reg/Q (constraint below create_generated_clock set it as RootPin, but design inst_clk_div/inst_clk_div_mux/inst_mux_nand2/hic_dnt_nand2/ZN as RootPin in CTS Spec file, as Fig. 4 Q pin (out_p) connects to Fig. 2 in0 actually)


create_clock [get_ports clk4x ] -name dummy_clk4x -period 0.5*0.833 -waveform "0 0.25*0.833"
create_generated_clock -name slice_clk_ctlr_phase_0 -edges {1 5 9} -add \
 -source [get_ports clk4x] \
 -master [get_clock dummy_clk4x] \
 [get_pin inst_clk_div/inst_clk_div_dff/hic_dnt_out_reg/Q]

#CTS Spec file

+ inst_clk_div/inst_clk_div_mux/inst_mux_nand2/hic_dnt_nand2/ZN
+ inst_clk_div/inst_clk_div_mux/inst_mux_nand0/hic_dnt_nand2/A1
+ inst_clk_div/inst_clk_div_mux/inst_mux_nand1/hic_dnt_nand2/A1
+ inst_clk_div/inst_clk_div_dffn/hic_dnt_out_reg/CPN
+ inst_clk_div/inst_clk_div0_dff/hic_dnt_out_reg/CP
+ inst_clk_div/inst_clk_div_dff/hic_dnt_out_reg/CP
AutoCTSRootPin clk4x
AutoCTSRootPin inst_clk_div/inst_clk_div_mux/inst_mux_nand2/hic_dnt_nand2/ZN

#As Fig. 4 Q pin (out_p) connects to Fig. 2 in0 actually, design inst_clk_div/inst_clk_div_mux/inst_mux_nand2/hic_dnt_nand2/ZN as RootPin, it is more clear to CTS.



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