Reorganize resource taxonomy.

The current hierarchy isn't particularly well suited to resources
like SDRAM or NOR flash, so make it much less fine-grained but easier
to use and less nitpicky.

2 files changed, 94 insertions, 0 deletions

diff --git a/nmigen_boards/extensions/__init__.py b/nmigen_boards/extensions/__init__.py
new file mode 100644
index 0000000..e69de29
--- /dev/null
+++ b/nmigen_boards/extensions/__init__.py
diff --git a/nmigen_boards/extensions/pmod.py b/nmigen_boards/extensions/pmod.py
new file mode 100644
index 0000000..331352c
--- /dev/null
+++ b/nmigen_boards/extensions/pmod.py
@@ -0,0 +1,94 @@
+# Reference: https://www.digilentinc.com/Pmods/Digilent-Pmod_%20Interface_Specification.pdf
+
+from nmigen.build import *
+
+
+__all__ = [
+    "PmodGPIOType1Resource",
+    "PmodSPIType2Resource",
+    "PmodSPIType2AResource",
+    "PmodUARTType3Resource",
+    "PmodUARTType4Resource",
+    "PmodUARTType4AResource",
+    "PmodHBridgeType5Resource",
+    "PmodDualHBridgeType6Resource",
+]
+
+
+def PmodGPIOType1Resource(name, number, *, pmod, extras=None):
+    return Resource(name, number,
+        Pins("1 2 3 4", dir="io", conn=("pmod", pmod)),
+        extras=extras
+    )
+
+
+def PmodSPIType2Resource(name, number, *, pmod, extras=None):
+    return Resource(name, number,
+        Subsignal("cs_n",  Pins("1", dir="o", conn=("pmod", pmod))),
+        Subsignal("clk",   Pins("2", dir="o", conn=("pmod", pmod))),
+        Subsignal("mosi",  Pins("3", dir="o", conn=("pmod", pmod))),
+        Subsignal("miso",  Pins("4", dir="i", conn=("pmod", pmod))),
+        extras=extras
+    )
+
+
+def PmodSPIType2AResource(name, number, *, pmod, extras=None):
+    return Resource(name, number,
+        Subsignal("cs_n",  Pins("1", dir="o", conn=("pmod", pmod))),
+        Subsignal("clk",   Pins("2", dir="o", conn=("pmod", pmod))),
+        Subsignal("mosi",  Pins("3", dir="o", conn=("pmod", pmod))),
+        Subsignal("miso",  Pins("4", dir="i", conn=("pmod", pmod))),
+        Subsignal("int",   Pins("7", dir="i", conn=("pmod", pmod))),
+        Subsignal("reset", Pins("8", dir="o", conn=("pmod", pmod))),
+        extras=extras
+        )
+
+
+def PmodUARTType3Resource(name, number, *, pmod, extras=None):
+    return Resource(name, number,
+        Subsignal("cts",   Pins("1", dir="o", conn=("pmod", pmod))),
+        Subsignal("rts",   Pins("2", dir="i", conn=("pmod", pmod))),
+        Subsignal("rx",    Pins("3", dir="i", conn=("pmod", pmod))),
+        Subsignal("tx",    Pins("4", dir="o", conn=("pmod", pmod))),
+        extras=extras
+    )
+
+
+def PmodUARTType4Resource(name, number, *, pmod, extras=None):
+    return Resource(name, number,
+        Subsignal("cts",   Pins("1", dir="i", conn=("pmod", pmod))),
+        Subsignal("tx",    Pins("2", dir="o", conn=("pmod", pmod))),
+        Subsignal("rx",    Pins("3", dir="i", conn=("pmod", pmod))),
+        Subsignal("rts",   Pins("4", dir="o", conn=("pmod", pmod))),
+        extras=extras
+    )
+
+
+def PmodUARTType4AResource(name, number, *, pmod, extras=None):
+    return Resource(name, number,
+        Subsignal("cts",   Pins("1", dir="i", conn=("pmod", pmod))),
+        Subsignal("tx",    Pins("2", dir="o", conn=("pmod", pmod))),
+        Subsignal("rx",    Pins("3", dir="i", conn=("pmod", pmod))),
+        Subsignal("rts",   Pins("4", dir="o", conn=("pmod", pmod))),
+        Subsignal("int",   Pins("7", dir="i", conn=("pmod", pmod))),
+        Subsignal("reset", Pins("8", dir="o", conn=("pmod", pmod))),
+        extras=extras
+    )
+
+
+def PmodHBridgeType5Resource(name, number, *, pmod, extras=None):
+    return Resource(name, number,
+        Subsignal("dir",   Pins("1", dir="o", conn=("pmod", pmod))),
+        Subsignal("en",    Pins("2", dir="o", conn=("pmod", pmod))),
+        Subsignal("sa",    Pins("3", dir="i", conn=("pmod", pmod))),
+        Subsignal("sb",    Pins("4", dir="i", conn=("pmod", pmod))),
+        extras=extras
+    )
+
+
+def PmodDualHBridgeType6Resource(name, number, *, pmod, extras=None):
+    return Resource(name, number,
+        Subsignal("dir",   Pins("1 3", dir="o", conn=("pmod", pmod))),
+        Subsignal("en",    Pins("2 4", dir="o", conn=("pmod", pmod))),
+        extras=extras
+    )