myhdl/example/cookbook/dff/dff.py

import myhdl
from myhdl import *
from myhdl.conversion import analyze


def dff(q, d, clk):

    @always(clk.posedge)
    def comb():
        q.next = d

    return comb


from random import randrange


def test_dff():

    q, d, clk = [Signal(bool(0)) for i in range(3)]

    dff_inst = dff(q, d, clk)

    @always(delay(10))
    def clkgen():
        clk.next = not clk

    @always(clk.negedge)
    def stimulus():
        d.next = randrange(2)

    return dff_inst, clkgen, stimulus


def simulate(timesteps):
    traceSignals.timescale = "1ps"
    tb = traceSignals(test_dff)
    sim = Simulation(tb)
    sim.run(timesteps)
    sim.quit()


simulate(2000)


def convert():
    q, d, clk = [Signal(bool(0)) for i in range(3)]
    toVerilog(dff, q, d, clk)
    analyze(dff, q, d, clk)


convert()