def __init__(self, platform, sys_clk_freq, sdram_rate="1:1"):
self.rst = Signal()
self.clock_domains.cd_sys = ClockDomain()
if sdram_rate == "1:2":
self.clock_domains.cd_sys2x = ClockDomain()
self.clock_domains.cd_sys2x_ps = ClockDomain(reset_less=True)
else:
self.clock_domains.cd_sys_ps = ClockDomain(reset_less=True)
# # #
# Clk / Rst
clk50 = platform.request("clk50")
# PLL
self.submodules.pll = pll = Cyclone10LPPLL(speedgrade="-C8")
self.comb += pll.reset.eq(self.rst)
pll.register_clkin(clk50, 50e6)
pll.create_clkout(self.cd_sys, sys_clk_freq)
if sdram_rate == "1:2":
pll.create_clkout(self.cd_sys2x, 2 * sys_clk_freq)
# theoretically 90 degrees, but increase to relax timing
pll.create_clkout(self.cd_sys2x_ps, 2 * sys_clk_freq, phase=180)
else:
pll.create_clkout(self.cd_sys_ps, sys_clk_freq, phase=90)
# SDRAM clock
sdram_clk = ClockSignal("sys2x_ps" if sdram_rate ==
"1:2" else "sys_ps")
self.specials += DDROutput(1, 0, platform.request("sdram_clock"),
sdram_clk)
def __init__(self, platform, sys_clk_freq):
self.clock_domains.cd_sys = ClockDomain()
self.clock_domains.cd_sys_ps = ClockDomain(reset_less=True)
# # #
# Clk / Rst
clk12 = platform.request("clk12")
# PLL
self.submodules.pll = pll = Cyclone10LPPLL(speedgrade="-A7")
self.comb += pll.reset.eq(~platform.request("cpu_reset"))
pll.register_clkin(clk12, 12e6)
pll.create_clkout(self.cd_sys, sys_clk_freq)
pll.create_clkout(self.cd_sys_ps, sys_clk_freq, phase=90)
# SDRAM clock
self.comb += platform.request("sdram_clock").eq(self.cd_sys_ps.clk)