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artiq/artiq/gateware/test/rtio/test_ttl_serdes.py

126 lines
4.1 KiB
Python

import unittest
from migen import *
from artiq.gateware.rtio.phy.ttl_serdes_generic import *
class _FakeSerdes:
def __init__(self):
self.o = Signal(8)
self.i = Signal(8)
self.oe = Signal()
class _TB(Module):
def __init__(self):
self.serdes = _FakeSerdes()
self.submodules.dut = ClockDomainsRenamer({"rio_phy": "sys", "rio": "sys"})(
InOut(self.serdes))
class TestTTLSerdes(unittest.TestCase):
def test_input(self):
tb = _TB()
def gen():
yield tb.dut.rtlink.o.address.eq(2)
yield tb.dut.rtlink.o.data.eq(0b11)
yield tb.dut.rtlink.o.stb.eq(1) # set sensitivity to rising + falling
yield
yield tb.dut.rtlink.o.stb.eq(0)
yield
self.assertEqual((yield tb.serdes.oe), 0)
self.assertEqual((yield tb.dut.rtlink.i.stb), 0)
yield tb.serdes.i.eq(0b11111110) # rising edge at fine_ts = 1
yield
yield tb.serdes.i.eq(0b11111111)
yield
self.assertEqual((yield tb.dut.rtlink.i.stb), 1)
self.assertEqual((yield tb.dut.rtlink.i.fine_ts), 1)
yield tb.serdes.i.eq(0b01111111) # falling edge at fine_ts = 7
yield
yield tb.serdes.i.eq(0b00000000)
yield
self.assertEqual((yield tb.dut.rtlink.i.stb), 1)
self.assertEqual((yield tb.dut.rtlink.i.fine_ts), 7)
yield tb.serdes.i.eq(0b11000000) # rising edge at fine_ts = 6
yield
yield tb.serdes.i.eq(0b11111111)
yield
self.assertEqual((yield tb.dut.rtlink.i.stb), 1)
self.assertEqual((yield tb.dut.rtlink.i.fine_ts), 6)
yield tb.dut.rtlink.o.address.eq(2)
yield tb.dut.rtlink.o.data.eq(0b01)
yield tb.dut.rtlink.o.stb.eq(1) # set sensitivity to rising only
yield
yield tb.dut.rtlink.o.stb.eq(0)
yield
yield tb.serdes.i.eq(0b00001111) # falling edge at fine_ts = 4
yield
yield tb.serdes.i.eq(0b00000000)
yield
# no strobe, sensitivity is rising edge
self.assertEqual((yield tb.dut.rtlink.i.stb), 0)
yield tb.serdes.i.eq(0b11110000) # rising edge at fine_ts = 4
yield
yield tb.serdes.i.eq(0b11111111)
yield
self.assertEqual((yield tb.dut.rtlink.i.stb), 1)
self.assertEqual((yield tb.dut.rtlink.i.fine_ts), 4)
run_simulation(tb, gen())
def test_output(self):
tb = _TB()
def gen():
yield tb.dut.rtlink.o.address.eq(1)
yield tb.dut.rtlink.o.data.eq(1)
yield tb.dut.rtlink.o.stb.eq(1) # set Output Enable to 1
yield
yield tb.dut.rtlink.o.stb.eq(0)
yield
yield
self.assertEqual((yield tb.serdes.oe), 1)
yield tb.dut.rtlink.o.address.eq(0)
yield tb.dut.rtlink.o.data.eq(1)
yield tb.dut.rtlink.o.fine_ts.eq(3)
yield tb.dut.rtlink.o.stb.eq(1) # rising edge at fine_ts = 3
yield
yield tb.dut.rtlink.o.stb.eq(0)
yield
self.assertEqual((yield tb.serdes.o), 0b11111000)
yield
self.assertEqual((yield tb.serdes.o), 0b11111111) # stays at 1
yield tb.dut.rtlink.o.data.eq(0)
yield tb.dut.rtlink.o.fine_ts.eq(0)
yield tb.dut.rtlink.o.stb.eq(1) # falling edge at fine_ts = 0
yield
yield tb.dut.rtlink.o.stb.eq(0)
yield
self.assertEqual((yield tb.serdes.o), 0b00000000)
yield
self.assertEqual((yield tb.serdes.o), 0b00000000)
yield tb.dut.rtlink.o.data.eq(1)
yield tb.dut.rtlink.o.fine_ts.eq(7)
yield tb.dut.rtlink.o.stb.eq(1) # rising edge at fine_ts = 7
yield
yield tb.dut.rtlink.o.stb.eq(0)
yield
self.assertEqual((yield tb.serdes.o), 0b10000000)
run_simulation(tb, gen())