lab2打包

lab2/朱梓涵24325356/scala/peripheral/CharacterDisplay.scala

@@ -0,0 +1,84 @@
+// Copyright 2022 Howard Lau
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package peripheral
+
+import chisel3.util.{MuxLookup, log2Up}
+import chisel3.{Bool, Bundle, Module, Mux, Output, UInt, Wire, _}
+import peripheral.ScreenInfo.{DisplayHorizontal, DisplayVertical}
+import riscv.Parameters
+
+object GlyphInfo {
+  val glyphWidth = 8
+  val glyphHeight = 16
+  // ASCII printable characters start from here
+  val spaceIndex = 1
+}
+
+object ScreenInfo {
+  val DisplayHorizontal = 640
+  val DisplayVertical = 480
+}
+
+object CharacterBufferInfo {
+  val CharCols = DisplayHorizontal / GlyphInfo.glyphWidth
+  val CharRows = DisplayVertical / GlyphInfo.glyphHeight
+  val Chars = CharCols * CharRows
+}
+
+class CharacterDisplay extends Module {
+  val io = IO(new Bundle() {
+    val bundle = new RAMBundle()
+
+    val x = Input(UInt(16.W))
+    val y = Input(UInt(16.W))
+    val video_on = Input(Bool())
+
+    val rgb = Output(UInt(24.W))
+  })
+
+  val mem = Module(new BlockRAM(CharacterBufferInfo.Chars / Parameters.WordSize))
+  mem.io.write_enable := io.bundle.write_enable
+  mem.io.write_data := io.bundle.write_data
+  mem.io.write_address := io.bundle.address
+  mem.io.write_strobe := io.bundle.write_strobe
+  mem.io.read_address := io.bundle.address
+  io.bundle.read_data := mem.io.read_data
+
+
+  val font_rom = Module(new FontROM)
+  val row = (io.y >> log2Up(GlyphInfo.glyphHeight)).asUInt
+  val col = (io.x >> log2Up(GlyphInfo.glyphWidth)).asUInt
+  val char_index = (row * CharacterBufferInfo.CharCols.U) + col
+  val offset = char_index(1, 0)
+  val ch = Wire(UInt(8.W))
+
+  mem.io.debug_read_address := char_index
+  ch := MuxLookup(
+    offset,
+    0.U,
+    IndexedSeq(
+      0.U -> mem.io.debug_read_data(7, 0).asUInt,
+      1.U -> mem.io.debug_read_data(15, 8).asUInt,
+      2.U -> mem.io.debug_read_data(23, 16).asUInt,
+      3.U -> mem.io.debug_read_data(31, 24).asUInt
+    )
+  )
+  font_rom.io.glyph_index := Mux(ch >= 32.U, ch - 31.U, 0.U)
+  font_rom.io.glyph_y := io.y(log2Up(GlyphInfo.glyphHeight) - 1, 0)
+
+  // White if pixel_on and glyph pixel on
+  val glyph_x = io.x(log2Up(GlyphInfo.glyphWidth) - 1, 0)
+  io.rgb := Mux(io.video_on && font_rom.io.glyph_pixel_byte(glyph_x), 0xFFFFFF.U, 0.U)
+}