nmigen_boards/dev/spi.py

   1 from nmigen.build import *
   2
   3
   4 __all__ = ["SPIResource"]
   5
   6
   7 def SPIResource(*args, cs, clk, mosi, miso, int=None, reset=None, attrs=None, role="host"):
   8     assert role in ("host", "device")
   9
  10     io = []
  11     if role == "host":
  12         io.append(Subsignal("cs", PinsN(cs, dir="o")))
  13         io.append(Subsignal("clk", Pins(clk, dir="o", assert_width=1)))
  14         io.append(Subsignal("mosi", Pins(mosi, dir="o", assert_width=1)))
  15         io.append(Subsignal("miso", Pins(miso, dir="i", assert_width=1)))
  16     else:  # device
  17         io.append(Subsignal("cs", PinsN(cs, dir="i", assert_width=1)))
  18         io.append(Subsignal("clk", Pins(clk, dir="i", assert_width=1)))
  19         io.append(Subsignal("mosi", Pins(mosi, dir="i", assert_width=1)))
  20         io.append(Subsignal("miso", Pins(miso, dir="oe", assert_width=1)))
  21     if int is not None:
  22         if role == "host":
  23             io.append(Subsignal("int", Pins(int, dir="i")))
  24         else:
  25             io.append(Subsignal("int", Pins(int, dir="oe", assert_width=1)))
  26     if reset is not None:
  27         if role == "host":
  28             io.append(Subsignal("reset", Pins(reset, dir="o")))
  29         else:
  30             io.append(Subsignal("reset", Pins(reset, dir="i", assert_width=1)))
  31     if attrs is not None:
  32         io.append(attrs)
  33     return Resource.family(*args, default_name="spi", ios=io)