59 lines
1.4 KiB
Python
59 lines
1.4 KiB
Python
from nmigen import *
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from nmigen.cli import main
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class Adder(Elaboratable):
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def __init__(self, width):
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self.a = Signal(width)
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self.b = Signal(width)
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self.o = Signal(width)
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def elaborate(self, platform):
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m = Module()
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m.d.comb += self.o.eq(self.a + self.b)
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return m
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class Subtractor(Elaboratable):
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def __init__(self, width):
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self.a = Signal(width)
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self.b = Signal(width)
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self.o = Signal(width)
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def elaborate(self, platform):
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m = Module()
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m.d.comb += self.o.eq(self.a - self.b)
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return m
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class ALU(Elaboratable):
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def __init__(self, width):
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self.op = Signal()
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self.a = Signal(width)
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self.b = Signal(width)
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self.o = Signal(width)
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self.add = Adder(width)
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self.sub = Subtractor(width)
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def elaborate(self, platform):
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m = Module()
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m.submodules.add = self.add
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m.submodules.sub = self.sub
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m.d.comb += [
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self.add.a.eq(self.a),
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self.sub.a.eq(self.a),
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self.add.b.eq(self.b),
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self.sub.b.eq(self.b),
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]
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with m.If(self.op):
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m.d.comb += self.o.eq(self.sub.o)
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with m.Else():
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m.d.comb += self.o.eq(self.add.o)
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return m
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if __name__ == "__main__":
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alu = ALU(width=16)
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main(alu, ports=[alu.op, alu.a, alu.b, alu.o])
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