Chisel入门

1.用Chisel点亮FPGA小灯

1.1 克隆项目

github：https://github.com/schoeberl/chisel-examples

1.2 编译运行

cmd命令如下

git clone https://github.com/schoeberl/chisel-examples.git
cd chisel-examples/hello-world/

Hello.scala

/*
 * This code is a minimal hardware described in Chisel.
 * 
 * Blinking LED: the FPGA version of Hello World
 */

import chisel3._

/**
 * The blinking LED component.
 */

class Hello extends Module {
  val io = IO(new Bundle {
    val led = Output(UInt(1.W))
  })
  val CNT_MAX = (50000000 / 2 - 1).U

  val cntReg = RegInit(0.U(32.W))
  val blkReg = RegInit(0.U(1.W))

  cntReg := cntReg + 1.U
  when(cntReg === CNT_MAX) {
    cntReg := 0.U
    blkReg := ~blkReg
  }
  io.led := blkReg
}

/**
 * An object extending App to generate the Verilog code.
 */
object Hello extends App {
  (new chisel3.stage.ChiselStage).emitVerilog(new Hello())
}

1.3 生成Verilog文件

Hello.v

module Hello(
  input   clock,
  input   reset,
  output  io_led
);
`ifdef RANDOMIZE_REG_INIT
  reg [31:0] _RAND_0;
  reg [31:0] _RAND_1;
`endif // RANDOMIZE_REG_INIT
  reg [31:0] cntReg; // @[Hello.scala 19:23]
  reg  blkReg; // @[Hello.scala 20:23]
  wire [31:0] _cntReg_T_1 = cntReg + 32'h1; // @[Hello.scala 22:20]
  assign io_led = blkReg; // @[Hello.scala 27:10]
  always @(posedge clock) begin
    if (reset) begin // @[Hello.scala 19:23]
      cntReg <= 32'h0; // @[Hello.scala 19:23]
    end else if (cntReg == 32'h17d783f) begin // @[Hello.scala 23:28]
      cntReg <= 32'h0; // @[Hello.scala 24:12]
    end else begin
      cntReg <= _cntReg_T_1; // @[Hello.scala 22:10]
    end
    if (reset) begin // @[Hello.scala 20:23]
      blkReg <= 1'h0; // @[Hello.scala 20:23]
    end else if (cntReg == 32'h17d783f) begin // @[Hello.scala 23:28]
      blkReg <= ~blkReg; // @[Hello.scala 25:12]
    end
  end
// Register and memory initialization
`ifdef RANDOMIZE_GARBAGE_ASSIGN
`define RANDOMIZE
`endif
`ifdef RANDOMIZE_INVALID_ASSIGN
`define RANDOMIZE
`endif
`ifdef RANDOMIZE_REG_INIT
`define RANDOMIZE
`endif
`ifdef RANDOMIZE_MEM_INIT
`define RANDOMIZE
`endif
`ifndef RANDOM
`define RANDOM $random
`endif
`ifdef RANDOMIZE_MEM_INIT
  integer initvar;
`endif
`ifndef SYNTHESIS
`ifdef FIRRTL_BEFORE_INITIAL
`FIRRTL_BEFORE_INITIAL
`endif
initial begin
  `ifdef RANDOMIZE
    `ifdef INIT_RANDOM
      `INIT_RANDOM
    `endif
    `ifndef VERILATOR
      `ifdef RANDOMIZE_DELAY
        #`RANDOMIZE_DELAY begin end
      `else
        #0.002 begin end
      `endif
    `endif
`ifdef RANDOMIZE_REG_INIT
  _RAND_0 = {1{`RANDOM}};
  cntReg = _RAND_0[31:0];
  _RAND_1 = {1{`RANDOM}};
  blkReg = _RAND_1[0:0];
`endif // RANDOMIZE_REG_INIT
  `endif // RANDOMIZE
end // initial
`ifdef FIRRTL_AFTER_INITIAL
`FIRRTL_AFTER_INITIAL
`endif
`endif // SYNTHESIS
endmodule

hello_top.v

/* Minimal top level for the Chisel Hello World.
  Wire reset to 0. */

module hello_top(input clk, output led);

  wire h_io_led;
  wire res;

  assign led = h_io_led;
  assign res = 1'h0;
  Hello h(.clock(clk), .reset(res),
       .io_led( h_io_led ));
endmodule

1.4 上板验证

1.4.1 创建quartus项目

板子型号为 EP4CE115F29C7

1.4.2 加入.v文件

1.4.3 绑定引脚

1.4.4 实现效果

暂未

2.在DE2-115开发板上重做Verilog实验

2.1 流水灯

2.1.1 修改scala文件

修改 Hello.scala 文件为：

import chisel3._
import chisel3.util._

class Hello extends Module {
  val io = IO(new Bundle {
    val led = Output(UInt(8.W))  // 8 位 LED 输出
  })

  val maxCount = (50000000 / 10).U  // 调整这个参数改变流水灯的速度（DE2-115 使用 50MHz 时钟）
  val counter = RegInit(0.U(32.W))
  val position = RegInit(0.U(3.W))

  // 计数器逻辑
  counter := counter + 1.U
  when(counter === maxCount) {
    counter := 0.U
    when(position === 7.U) {
      position := 0.U
    }.otherwise {
      position := position + 1.U
    }
  }

  // LED 输出逻辑
  io.led := (1.U << position)
}

object Hello extends App {
  (new chisel3.stage.ChiselStage).emitVerilog(new Hello())
}

2.1.2 重新编译

Hello.v

module Hello(
  input        clock,
  input        reset,
  output [7:0] io_led
);
`ifdef RANDOMIZE_REG_INIT
  reg [31:0] _RAND_0;
  reg [31:0] _RAND_1;
`endif // RANDOMIZE_REG_INIT
  reg [31:0] counter; // @[Hello.scala 10:24]
  reg [2:0] position; // @[Hello.scala 11:25]
  wire [31:0] _counter_T_1 = counter + 32'h1; // @[Hello.scala 14:22]
  wire [2:0] _position_T_1 = position + 3'h1; // @[Hello.scala 20:28]
  assign io_led = 8'h1 << position; // @[Hello.scala 25:18]
  always @(posedge clock) begin
    if (reset) begin // @[Hello.scala 10:24]
      counter <= 32'h0; // @[Hello.scala 10:24]
    end else if (counter == 32'h4c4b40) begin // @[Hello.scala 15:30]
      counter <= 32'h0; // @[Hello.scala 16:13]
    end else begin
      counter <= _counter_T_1; // @[Hello.scala 14:11]
    end
    if (reset) begin // @[Hello.scala 11:25]
      position <= 3'h0; // @[Hello.scala 11:25]
    end else if (counter == 32'h4c4b40) begin // @[Hello.scala 15:30]
      if (position == 3'h7) begin // @[Hello.scala 17:28]
        position <= 3'h0; // @[Hello.scala 18:16]
      end else begin
        position <= _position_T_1; // @[Hello.scala 20:16]
      end
    end
  end
// Register and memory initialization
`ifdef RANDOMIZE_GARBAGE_ASSIGN
`define RANDOMIZE
`endif
`ifdef RANDOMIZE_INVALID_ASSIGN
`define RANDOMIZE
`endif
`ifdef RANDOMIZE_REG_INIT
`define RANDOMIZE
`endif
`ifdef RANDOMIZE_MEM_INIT
`define RANDOMIZE
`endif
`ifndef RANDOM
`define RANDOM $random
`endif
`ifdef RANDOMIZE_MEM_INIT
  integer initvar;
`endif
`ifndef SYNTHESIS
`ifdef FIRRTL_BEFORE_INITIAL
`FIRRTL_BEFORE_INITIAL
`endif
initial begin
  `ifdef RANDOMIZE
    `ifdef INIT_RANDOM
      `INIT_RANDOM
    `endif
    `ifndef VERILATOR
      `ifdef RANDOMIZE_DELAY
        #`RANDOMIZE_DELAY begin end
      `else
        #0.002 begin end
      `endif
    `endif
`ifdef RANDOMIZE_REG_INIT
  _RAND_0 = {1{`RANDOM}};
  counter = _RAND_0[31:0];
  _RAND_1 = {1{`RANDOM}};
  position = _RAND_1[2:0];
`endif // RANDOMIZE_REG_INIT
  `endif // RANDOMIZE
end // initial
`ifdef FIRRTL_AFTER_INITIAL
`FIRRTL_AFTER_INITIAL
`endif
`endif // SYNTHESIS
endmodule

2.1.3 引脚分配

2.1.4 编译下载

2.1.5 实现效果

暂未

参考链接

1.https://blog.youkuaiyun.com/weixin_68811361/article/details/139279336
2.Chisel-book： https://wwu.lanzoue.com/isdim08x8x5i