tristateSignal_example.py

from myhdl import Signal, TristateSignal, block, instance, delay, always_comb


@block
def foo(clk, iopin):
    
    tri = Signal(bool(0))
    iopindriver = iopin.driver()
    
    @always_comb
    def statedriver():
        iopindriver.next = clk if tri else None
    
    @instance
    def statechange():
        while True:
            tri.next = False
            yield delay(50)  # can implement clkwait as you said
            tri.next = True
            yield delay(50)  # can implement clkwait as you said
            
    return statedriver, statechange


@block
def test_foo():
    
    clk = Signal(bool(0))
    iopin = TristateSignal(bool(0))
    fooinst = foo(clk, iopin)
    
    @instance
    def clkdriver():
        while True:
            clk.next = not clk
            yield delay(10)
    
    return clkdriver, fooinst

testfooinst = test_foo()
testfooinst.config_sim(trace=True)
testfooinst.run_sim(duration=1000)