initial coordinator

remove 4xclocking for double-fetch architecture (still using 2xclock for
better S/H)

src/groovylight/bitslicer.py

@@ -1,9 +1,8 @@
-from amaranth import Array, Module, Cat, Mux, ShapeLike, Signal, Assert, unsigned
+from amaranth import Module, Cat, Mux, ShapeLike, Signal, Assert, unsigned
 from amaranth.build import Platform
 from amaranth.lib import wiring, data
 from amaranth.lib.wiring import In, Out
 from amaranth.lib.memory import Memory, ReadPort, WritePort
-from amaranth.sim import Simulator
 from amaranth.utils import ceil_log2
 
 
@@ -18,7 +17,7 @@ class RGBLayout(data.StructLayout):
         )
 
 
-Rgb888Layout = RGBLayout(8, 8, 8)
+Rgb666Layout = RGBLayout(6, 6, 6)
 
 Rgb111Layout = RGBLayout(1, 1, 1)
 
@@ -113,28 +112,31 @@ class SwapBuffer(wiring.Component):
             shape=self.data_shape, depth=self.depth, init=[]
         )
 
-        read0 = self.bram0.read_port()
-        write0 = self.bram0.write_port()
-        read1 = self.bram1.read_port()
-        write1 = self.bram1.write_port()
-
-        # for name, member in self.write_port.signature.members.items():
-        #     m.d.comb += self.write_port.members[name].eq(Mux(self.selector, write0[name], write1[name]))
-        #
+        rd0 = self.bram0.read_port()
+        wr0 = self.bram0.write_port()
+        rd1 = self.bram1.read_port()
+        wr1 = self.bram1.write_port()
 
         m.d.comb += [
-            write0.addr.eq(self.write_port.addr),
-            write1.addr.eq(self.write_port.addr),
-            write0.en.eq(~self.selector),
-            write1.en.eq(self.selector),
-            # self.write_port.data.eq(Mux(self.selector, write0.data, write1.data)),
-            write0.data.eq(self.write_port.data),
-            write1.data.eq(self.write_port.data),
-            read0.addr.eq(self.read_port.addr),
-            read1.addr.eq(self.read_port.addr),
-            read0.en.eq(~self.selector),
-            read1.en.eq(self.selector),
-            self.read_port.data.eq(Mux(self.selector, read1.data, read0.data)),
+            # wr addres
+            wr0.addr.eq(self.write_port.addr),
+            wr1.addr.eq(self.write_port.addr),
+            # write enables are based on selector
+            wr0.en.eq(~self.selector),
+            wr1.en.eq(self.selector),
+            # connect write data. This is FINE because
+            # there is one driver (the external writer)
+            # and we en based on selector so the other one isn't active
+            wr0.data.eq(self.write_port.data),
+            wr1.data.eq(self.write_port.data),
+            # connect rd address lines
+            rd0.addr.eq(self.read_port.addr),
+            rd1.addr.eq(self.read_port.addr),
+            rd0.en.eq(~self.selector),
+            rd1.en.eq(self.selector),
+            # we do this because the read_data lines are driven, this prevents
+            # double-driver situations even though we en using selector above
+            self.read_port.data.eq(Mux(self.selector, rd1.data, rd0.data)),
         ]
 
         return m
@@ -146,33 +148,48 @@ class Hub75StringDriver(wiring.Component):
     it should send.
     """
 
-    bcm_select: In(3)
-    done: Out(1)
-    start: In(1)
-    bram_port: In(ReadPort.Signature(addr_width=9, shape=Rgb888Layout))
-    display_out: Out(Hub75Data())  # data signal output.
-
     def __init__(self, panel_length: int = 128, *, src_loc_at=0):
         self.panel_length = panel_length
-        super().__init__(None, src_loc_at=src_loc_at)
+        super().__init__(
+            {
+                "bcm_select": In(3),
+                "done": Out(1),
+                "start": In(1),
+                "bram_port": In(
+                    ReadPort.Signature(
+                        addr_width=ceil_log2(panel_length),
+                        shape=data.ArrayLayout(Rgb666Layout, 2),
+                    )
+                ),
+                "display_out": Out(Hub75Data()),
+            },
+            src_loc_at=src_loc_at,
+        )
 
     def elaborate(self, platform: Platform) -> Module:
         m = Module()
 
-        # add two memories
-
-        self._counter = counter = Signal(32)
+        self._counter = counter = Signal(32)  # unused count is optimized out
         m.d.sync += counter.eq(counter + 1)
 
-        ram_rgb_slice = Cat(
-            self.bram_port.data["red"].bit_select(self.bcm_select, 1),
-            self.bram_port.data["blue"].bit_select(self.bcm_select, 1),
-            self.bram_port.data["green"].bit_select(self.bcm_select, 1),
+        ram_rgb0_slice = Cat(
+            self.bram_port.data[0]["red"].bit_select(self.bcm_select, 1),
+            self.bram_port.data[0]["blue"].bit_select(self.bcm_select, 1),
+            self.bram_port.data[0]["green"].bit_select(self.bcm_select, 1),
         )
+        ram_rgb1_slice = Cat(
+            self.bram_port.data[1]["red"].bit_select(self.bcm_select, 1),
+            self.bram_port.data[1]["blue"].bit_select(self.bcm_select, 1),
+            self.bram_port.data[1]["green"].bit_select(self.bcm_select, 1),
+        )
+        m.d.comb += [
+            self.display_out.rgb0.eq(ram_rgb0_slice),
+            self.display_out.rgb1.eq(ram_rgb1_slice),
+        ]
+        m.d.sync += Assert(self.bcm_select < 6)
 
-        pixnum = Signal(range(self.panel_length), init=self.panel_length - 1)
-        pixrow = Signal(1, init=0)
-        m.d.comb += self.bram_port.addr.eq(Cat(pixrow, pixnum))
+        pixnum = Signal(ceil_log2(self.panel_length), init=self.panel_length - 1)
+        m.d.comb += self.bram_port.addr.eq(pixnum)
 
         with m.FSM():
             with m.State("init"):
@@ -180,42 +197,22 @@ class Hub75StringDriver(wiring.Component):
                     self.done.eq(0),
                     counter.eq(0),
                     pixnum.eq(self.panel_length - 1),
-                    pixrow.eq(0),
                 ]
                 with m.If(self.start == 1):
                     m.d.sync += self.bram_port.en.eq(1)
                     m.next = "writerow"
-            with m.State("prefetch"):
-                with m.If(counter == 0):
-                    m.d.sync += pixrow.eq(0)
-                with m.Elif(counter == 1):
-                    m.d.sync += pixrow.eq(1)
-                with m.Elif(counter == 2):
-                    m.d.sync += self.display_out.rgb0.eq(ram_rgb_slice)
-                with m.Elif(counter == 3):
-                    m.d.sync += [self.display_out.rgb1.eq(ram_rgb_slice), counter.eq(0)]
-                    m.next = "writerow"
             with m.State("writerow"):
-                with m.If(counter[0:1] == 0):
-                    # rising edge of the clock
-                    m.d.sync += pixrow.eq(0)
+                with m.If(counter[0] == 0):
+                    # do nothing
+                    pass
 
-                with m.If(counter[0:1] == 1):
-                    m.d.sync += [
-                        pixrow.eq(1),
-                        self.display_out.rgb0.eq(ram_rgb_slice),
-                    ]
-                with m.If(counter[0:1] == 2):
-                    m.d.sync += [
-                        pixnum.eq(pixnum - 1),
-                        pixrow.eq(0),
-                        self.display_out.rgb1.eq(ram_rgb_slice),
-                    ]
-                with m.If(counter == 128 * 2 + 1):
+                with m.If((counter[0] == 1) & (pixnum != 0)):
+                    m.d.sync += pixnum.eq(pixnum - 1)
 
+                with m.Else():
                     m.next = "done"
             with m.State("done"):
-                m.d.sync += self.done.eq(1)
+                m.d.sync += [self.done.eq(1), self.bram_port.en.eq(0)]
                 m.next = "init"
 
         return m
@@ -226,10 +223,40 @@ class Hub75Coordinator(wiring.Component):
 
     def __init__(self, n_strings=1):
         self.n_strings = n_strings
-        super().__init__()
+        super().__init__(
+            {
+                "ctrl": Out(Hub75Ctrl),
+                "data": data.ArrayLayout(Hub75Data, n_strings),
+                # TODO: fetching routine? maybe it's passed through.
+            }
+        )
 
     def elaborate(self, platform: Platform) -> Module:
         m = Module()
+        # swapline is which buffer we are using vs sending out.
+        swapline = Signal(1)
+
+        # for each string, spawn a swapbuffer + stringdriver and connect.
+        # don't worry about fetching for now.
+        self.strings = strings = []
+        self.buffers = bufs = []
+        donearr = []
+        startStrings = Signal(1)
+        stringsDone = Signal(1)
+        for i in range(self.n_strings):
+            sb = SwapBuffer(depth=128, shape=data.ArrayLayout(Rgb666Layout, 2))
+            bufs += sb
+            stringdriver = Hub75StringDriver(128)
+            strings += stringdriver
+            wiring.connect(m, sb.read_port, stringdriver.bram_port)
+            m.d.comb += [
+                self.data[i].eq(stringdriver.display_out),
+                stringdriver.start.eq(startStrings),
+                sb.selector.eq(swapline),
+            ]
+            m.submodules += [sb, stringdriver]
+            donearr += stringdriver.done
+        m.d.comb += stringsDone.eq(Cat(*donearr).all())
 
         return m
 
@@ -239,6 +266,10 @@ class Hub75EDriver(wiring.Component):
     This version is faster than most implementations by merging the exposure
     period and the data-write period to happen simultaneously. As a result,
     the display can be brighter due to higher duty cycle.
+
+
+    NOTICE: this is a direct port of the old verilog code. It isn't up to date with the
+    modified structure. Notably, it uses RGB888 with double-fetch (4xclocking)
     """
 
     start: In(1)

src/groovylight/geom.py

@@ -0,0 +1,124 @@
+# Geometry-related classes and functions. Manipulations and
+# generation of panel-layout metadata for use in the HDL.
+
+from enum import Enum
+from dataclasses import dataclass
+
+
+@dataclass(frozen=True, order=True)
+class Coord:
+    """Coordinate class. Uses computer-graphics standard coordinate system,
+    where X=0, Y=0 is top left. +X goes right. +Y goes down.
+    """
+
+    x: int
+    y: int
+    
+    def __post_init__(self):
+        if self.x < 0 or self.y < 0:
+            raise RuntimeError("x and y must both be >= 0")
+
+
+@dataclass(frozen=True)
+class BBox:
+    """Bounding box class. Captures the top left coordinate and bottom right coordinate
+    of an object"""
+
+    topleft: Coord
+    bottomright: Coord
+
+    def __post_init__(self):
+        if not self.topleft < self.bottomright:
+            raise RuntimeError("topleft must be strictly less than bottomright")
+
+    def contains(self, c: Coord) -> bool:
+        return c > self.topleft and c < self.bottomright
+
+
+@dataclass(frozen=True)
+class DisplayDimensions:
+    """Represents the dimensions of a display string, in length x height. Notably
+    this is in local coordinates to the display. The display top left is 0,0.
+    Uses length/height notation to separate it from coord
+    """
+
+    length: int
+    height: int
+
+
+class DisplayRotation(Enum):
+    """Display rotation enums. The names indicate the general direction
+    of data flow. most normal displays (LCDs, CRTs) are LEFTRIGHT,
+    since they scan left-to-right, top to bottom.
+
+    Note that the direction of subsequent lines is not always clear.
+    They are enumerated below:
+        LEFTRIGHT -> next line is below it (-Y)
+        UPDOWN -> next line is to the LEFT (-X)
+        DOWNUP -> next line is to the RIGHT (+X)
+        RIGHTLEFT -> next line is above it (+Y)
+
+    Generally, prefer LEFTRIGHT/UPDOWN over other rotations.
+    """
+
+    LEFTRIGHT = 0
+    UPDOWN = 1
+    DOWNUP = 2
+    RIGHTLEFT = 3  # why are you like this.
+
+
+@dataclass(frozen=True)
+class _DisplayString:
+    """Internal class to represent a string of HUB75 displays.
+
+    position: (X,Y) coordinates of the local top-left of the display
+
+    dimensions: (length, height) local-coordinate dimensions of the display.
+
+    rotation: DisplayRotation: the orientation of the display.
+    """
+
+    position: Coord
+    dimensions: DisplayDimensions
+    rotation: DisplayRotation
+
+    @property
+    def bbox(self) -> BBox:
+        """Returns the bounding box of the display based on the dimensions, position, and rotation."""
+        x = self.position.x
+        y = self.position.y
+        l = self.dimensions.length
+        h = self.dimensions.height
+        match self.rotation:
+            case DisplayRotation.LEFTRIGHT:
+                return BBox(Coord(x, y), Coord(x + l, y + h))
+            case DisplayRotation.UPDOWN:
+                return BBox(Coord(x - h, y), Coord(x, y + l))
+            case DisplayRotation.DOWNUP:
+                return BBox(Coord(x, y + l), Coord(x + h, y))
+            case DisplayRotation.RIGHTLEFT:
+                return BBox(Coord(x - l, y - h), Coord(x, y))
+
+    def contains_pix(self, coord: Coord) -> bool:
+        """Checks if the given coordinate is inside this display."""
+        return self.bbox.contains(coord)
+
+
+class DisplayGeometry:
+    """Represents a display based on several strings in different positions.
+    """
+
+    def __init__(self, *, strict: bool = False):
+        self.strict = strict
+        pass
+
+    def add_string(self, position: (int, int), rot: int, dimensions: (int, int)):
+        """Add a new string to the display. This new string is located at
+        a specific point, and has a direction, along with dimension that reveal
+        the number of address lines (typically 64, with 1:32 selection so 5 address
+        bits) and the total length of the string which is used to size the line
+        buffers.
+
+        When in strict mode, this method may throw an exception if this new string
+        will overlap with an existing string.
+        """

src/groovylight/lineram.py

@@ -1,12 +0,0 @@
-from amaranth import Module, Cat, Signal, Assert, unsigned
-from amaranth.build import Platform
-
-from amaranth.lib import wiring, data
-from amaranth.lib.wiring import In, Out
-from amaranth.lib.memory import Memory
-# file to wrap line ram using PDPw16KD
-# this is tricky.
-
-
-def lineram():
-    return Memory(shape=unsigned(24), depth=512)

src/groovylight/test_hub75.py

@@ -5,17 +5,19 @@ from amaranth.lib.wiring import In, Out
 from amaranth.lib.memory import Memory, WritePort
 from amaranth.sim import Simulator
 
-from .bitslicer import Hub75StringDriver, Rgb888Layout
+from .bitslicer import Hub75StringDriver, Rgb666Layout
 
 
 def test_stringdriver():
-    # the string driver test must 
+    # the string driver test must
     # 1. finish
     # 2. strobe through all of the data in the array
     # 3. slice the correct bit from the data.
     m = Module()
     m.submodules.dut = dut = Hub75StringDriver()
-    m.submodules.mem = mem = Memory(shape=Rgb888Layout, depth=512, init=[])
+    m.submodules.mem = mem = Memory(
+        shape=data.ArrayLayout(Rgb666Layout, 2), depth=128, init=[]
+    )
     port = mem.read_port()
 
     wiring.connect(m, port, dut.bram_port)
@@ -26,12 +28,11 @@ def test_stringdriver():
         ctx.set(dut.start, 1)
         await ctx.tick()
         ctx.set(dut.start, 0)
-        assert(ctx.get(dut.bram_port.en) == 1)
+        assert ctx.get(dut.bram_port.en) == 1
         pass
 
     sim = Simulator(m)
     sim.add_clock(1e-6)
 
     with sim.write_vcd("output.vcd"):
-
         sim.run_until(1e-6 * 1000)

src/groovylight/test_swapbuffer.py

@@ -5,11 +5,11 @@ from amaranth.lib.wiring import In, Out
 from amaranth.lib.memory import Memory, WritePort
 from amaranth.sim import Simulator
 
-from .bitslicer import Hub75StringDriver, Rgb888Layout, SwapBuffer
+from .bitslicer import Hub75StringDriver, Rgb666Layout, SwapBuffer
 
 
 def test_swapbuffer():
-    dut = SwapBuffer(Rgb888Layout, 512)
+    dut = SwapBuffer(Rgb666Layout, 512)
     sim = Simulator(dut)
     sim.add_clock(1e-6)