45 lines
1.3 KiB
Python
45 lines
1.3 KiB
Python
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import enum
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from amaranth.build import Platform
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from amaranth import *
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class ClockState(enum.Enum):
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LOW = 0
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FALLING = 1
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HIGH = 2
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RISING = 3
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class ExiClock(Elaboratable):
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def __init__(self):
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# Ports
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self.exiClk = Signal()
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self.exiClkState = Signal(2)
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# State
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self.prevExiClkValid = Signal()
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self.prevExiClk = Signal()
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self.prevExiClkState = Signal(2)
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def elaborate(self, platform: Platform):
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m = Module()
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with m.If(self.prevExiClkValid):
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with m.If(self.prevExiClkState == ClockState.FALLING):
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m.d.comb += self.exiClkState.eq(ClockState.LOW)
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with m.Elif(self.prevExiClkState == ClockState.RISING):
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m.d.comb += self.exiClkState.eq(ClockState.HIGH)
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with m.Else():
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with m.If(self.prevExiClk ^ self.exiClk):
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m.d.comb += self.exiClkState.eq(Cat(1, self.exiClk))
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with m.Else():
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m.d.comb += self.exiClkState.eq(Cat(0, self.exiClk))
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m.d.sync += self.prevExiClkState.eq(self.exiClkState)
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m.d.sync += self.prevExiClk.eq(self.exiClk)
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m.d.sync += self.prevExiClkValid.eq(1)
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return m
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