46 lines
1.3 KiB
Python
46 lines
1.3 KiB
Python
# SPDX-License-Identifier: AGPL-3.0-Only
|
|
# Copyright (C) 2022 Sean Anderson <seanga2@gmail.com>
|
|
|
|
import random
|
|
|
|
import cocotb
|
|
from cocotb.clock import Clock
|
|
from cocotb.regression import TestFactory
|
|
from cocotb.triggers import FallingEdge, RisingEdge, Timer
|
|
|
|
from .util import compare_lists, timeout, send_recovered_bits, with_valids
|
|
|
|
def nrzi_decode(bits):
|
|
last = 1
|
|
for bit in bits:
|
|
yield bit ^ last
|
|
last = bit
|
|
|
|
@timeout(10, 'us')
|
|
async def test_rx(decoder, valids):
|
|
decoder.nrzi_valid.value = 0
|
|
await Timer(1)
|
|
await cocotb.start(Clock(decoder.clk, 8, units='ns').start())
|
|
|
|
ins = [random.randrange(2) for _ in range(1000)]
|
|
await cocotb.start(send_recovered_bits(decoder.clk, decoder.nrzi,
|
|
decoder.nrzi_valid, ins, valids))
|
|
|
|
outs = []
|
|
await RisingEdge(decoder.clk)
|
|
for _ in ins:
|
|
await RisingEdge(decoder.clk)
|
|
valid = decoder.nrz_valid.value
|
|
if valid == 0:
|
|
pass
|
|
elif valid == 1:
|
|
outs.append(decoder.nrz[1].value)
|
|
else:
|
|
outs.append(decoder.nrz[1].value)
|
|
outs.append(decoder.nrz[0].value)
|
|
|
|
# Ignore the first bit, since it is influenced by the initial value
|
|
compare_lists(list(nrzi_decode(ins))[1:], outs[1:])
|
|
|
|
with_valids(globals(), test_rx)
|