litex/examples/basic/fsm.py

31 lines
831 B
Python

from migen.fhdl.std import *
from migen.fhdl import verilog
from migen.genlib.fsm import FSM, NextState, NextValue
class Example(Module):
def __init__(self):
self.s = Signal()
self.counter = Signal(8)
myfsm = FSM()
self.submodules += myfsm
myfsm.act("FOO",
self.s.eq(1),
NextState("BAR")
)
myfsm.act("BAR",
self.s.eq(0),
NextValue(self.counter, self.counter + 1),
NextState("FOO")
)
self.be = myfsm.before_entering("FOO")
self.ae = myfsm.after_entering("FOO")
self.bl = myfsm.before_leaving("FOO")
self.al = myfsm.after_leaving("FOO")
example = Example()
print(verilog.convert(example, {example.s, example.counter, example.be, example.ae, example.bl, example.al}))