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MRenn
New Contributor
7 years agoTiming violation with Altera GPIO in DDR mode
I have a setup violation at the register after the input register. The input register is constrained as described in AN433. set_input_delay -add_delay -clock virt_adc_clk -min -0.6 [get...
MRenn
New Contributor
7 years agoThank you for your answer.
I tried this:
create_clock -period "262.144 MHz" -name virt_adc_clk
create_clock -period "262.144 MHz" -name {SAMPLE_CLK_1} {SAMPLE_CLK_1}
create_generated_clock -name {CLK262} \
-source [get_ports {SAMPLE_CLK_1}] \
-divide_by 1 \
-multiply_by 1 \
-phase 90 \
-duty_cycle 50.00 { iopll262|iopll_0|altera_iopll_i|twentynm_pll|iopll_inst|outclk[0] }
derive_pll_clocks -create_base_clocksand also this without phase shift:
create_clock -period "262.144 MHz" -name virt_adc_clk
create_clock -period "262.144 MHz" -name {SAMPLE_CLK_1} {SAMPLE_CLK_1}
create_generated_clock -name {CLK262} \
-source [get_ports {SAMPLE_CLK_1}] \
-divide_by 1 \
-multiply_by 1 \
-duty_cycle 50.00 { iopll262|iopll_0|altera_iopll_i|twentynm_pll|iopll_inst|outclk[0] }
derive_pll_clocks -create_base_clocksThe violations are the same. For the appplication is no difference because we use the ADC AD9652 and we adjust the DCO by starting the system.