mem2d_edit.py

from random import randint
from myhdl import *
 
def switchchannels(mem2d, q, clk):
 
    @always(clk.posedge)
    def switch():
        #print('switch')
        #print(mem2d)
        x = mem2d[0]
        mem2d[0] = mem2d[1]
        mem2d[1] = x
        #print(mem2d)
 
    @always(clk.posedge)
    def logic():
        #print('logic')
        #print(q, mem2d)
        mem2d[0][0].next = mem2d[0][1]
        mem2d[0][1].next = q
        #print(mem2d)
        
    return switch, logic
        
from random import randrange
 
def test_switchchannels():
    
    clk = Signal(bool(0))
    q = Signal(intbv(0)[4:])
    mem2d = [[Signal(intbv(0)[4:]), Signal(intbv(0)[4:])] , 
             [Signal(intbv(1)[4:]), Signal(intbv(1)[4:])]]
 
    print('init')
    print(q)
    print(clk)
    print(mem2d)
 
    switch_inst = switchchannels(mem2d, q, clk)
    
    @always(delay(10))
    def clkgen():
        clk.next = not clk
 
    @instance
    def stimulus():
        for ii in range(10):
            q.next = randint(0,15)
            print("time {:<8d}: q = {}".format(now(), int(q)))
            for ii,row in enumerate(mem2d):
                print("   {}: {:4d}  {:4d}".format(ii, *map(int, row)))
            yield clk.posedge

        raise StopSimulation
 
    return switch_inst, clkgen, stimulus
 
def simulate(timesteps):
    traceSignals.timescale = "1ps"
    tb = traceSignals(test_switchchannels)
    sim = Simulation(tb)
    sim.run()
 
simulate(40)

Output

$ python mem2d_edit.py
init
0
False
[[Signal(intbv(0L)), Signal(intbv(0L))], [Signal(intbv(1L)), Signal(intbv(1L))]]
time 0       : q = 0
   0:    0     0
   1:    1     1
time 10      : q = 10
   0:    1     1
   1:    0     0
time 30      : q = 7
   0:    1    10
   1:    0     0
time 50      : q = 0
   0:   10     7
   1:    0     0
time 70      : q = 9
   0:    7     0
   1:    0     0
time 90      : q = 2
   0:    0     9
   1:    0     0
time 110     : q = 13
   0:    9     2
   1:    0     0
time 130     : q = 14
   0:    2    13
   1:    0     0
time 150     : q = 1
   0:   13    14
   1:    0     0
time 170     : q = 14
   0:   14     1
   1:    0     0