litex-boards/litex_boards/platforms/terasic_de2_115.py

#
# This file is part of LiteX-Boards.
#
# Copyright (c) 2019 Antony Pavlov <antonynpavlov@gmail.com>
# SPDX-License-Identifier: BSD-2-Clause

from litex.build.generic_platform import *
from litex.build.altera import AlteraPlatform
from litex.build.altera.programmer import USBBlaster

# IOs ----------------------------------------------------------------------------------------------

_io = [
    # Clk
    ("clk50", 0, Pins("Y2"), IOStandard("3.3-V LVTTL")),

    # Serial
    ("serial", 0,
        Subsignal("tx", Pins("G9"), IOStandard("3.3-V LVTTL")), # Use built-in Tx RS32 port
        Subsignal("rx", Pins("G12"), IOStandard("3.3-V LVTTL"))  #  Use built-in Rx RS32 port
    ),

    # SDR SDRAM
    ("sdram_clock", 0, Pins("AE5"), IOStandard("3.3-V LVTTL")),
    ("sdram", 0,
        Subsignal("a",     Pins(
            "R6 V8 U8 P1 V5 W8 W7 AA7",
            "Y5 Y6 R5 AA5 Y7")),
        Subsignal("ba",    Pins("U7 R4")),
        Subsignal("cs_n",  Pins("T4")),
        Subsignal("cke",   Pins("AA6")),
        Subsignal("ras_n", Pins("U6")),
        Subsignal("cas_n", Pins("V7")),
        Subsignal("we_n",  Pins("V6")),
        Subsignal("dq", Pins(
            "W3 W2  V4  W1  V3  V2  V1  U3",
            "Y3 Y4 AB1 AA3 AB2 AC1 AB3 AC2")),
        Subsignal("dm", Pins("U2 W4")),
        IOStandard("3.3-V LVTTL")
    ),
]

# Platform -----------------------------------------------------------------------------------------

class Platform(AlteraPlatform):
    default_clk_name   = "clk50"
    default_clk_period = 1e9/50e6

    def __init__(self):
        AlteraPlatform.__init__(self, "EP4CE115F29C7", _io)

    def create_programmer(self):
        return USBBlaster()

    def do_finalize(self, fragment):
        AlteraPlatform.do_finalize(self, fragment)
        self.add_period_constraint(self.lookup_request("clk50", loose=True), 1e9/50e6)