Forum Discussion
internal osc & global clk
is there way to get the internal osc on cyclone 3 or 4 use the global clk network? if so whats the .qsf command for that? i think the 80mhz internal osc is not using the global clk network.
3 Replies
- SyafieqS
Super Contributor
Hi Wen,
You may need to refer to KDB below on how to do the assignment for the GCLK,PCLK,RCLK etc.
- s002wjh
New Contributor
so if timing my constraint is like this
create_clock -name "div2_clk" -period 25.000 [get_registers {frequency_divider:frequency_divider_inst|clk_div2}]
create_generated_clock -divide_by 2 -source [get_registers {frequency_divider:frequency_divider_inst|clk_div2}] -name div4_clk [get_registers {frequency_divider:frequency_divider_inst|clk_div4}]do i need write something like this? for global clk network? i divide the internal osc by 4
set_location_assignment CLKCTRL_G2 -to "get_registers {frequency_divider:frequency_divider_inst|clk_div4}~clkctrl"
- SyafieqS
Super Contributor
Hi Wen,
May I know if the KDB given able to assign the internal oscillator to GCLK? Alternatively, in assignment editor, you can select global signal and assign global clock to the osc and you can reflect in your qsf.