Chisel3 - Tutorial - Adder4

import chisel3._
import chisel3.util._
 
//A 4-bit adder with carry in and carry out
class Adder4 extends Module {
val io = IO(new Bundle {
val A = Input(UInt(4.W))
val B = Input(UInt(4.W))
val Cin = Input(UInt(1.W))
val Sum = Output(UInt(4.W))
val Cout = Output(UInt(1.W))
})
//Adder for bit 0
val Adder0 = Module(new FullAdder())
Adder0.io.a := io.A(0)
Adder0.io.b := io.B(0)
Adder0.io.cin := io.Cin
// val s0 = Adder0.io.sum
//Adder for bit 1
val Adder1 = Module(new FullAdder())
Adder1.io.a := io.A(1)
Adder1.io.b := io.B(1)
Adder1.io.cin := Adder0.io.cout
// val s1 = Cat(Adder1.io.sum, s0)
//Adder for bit 2
val Adder2 = Module(new FullAdder())
Adder2.io.a := io.A(2)
Adder2.io.b := io.B(2)
Adder2.io.cin := Adder1.io.cout
// val s2 = Cat(Adder2.io.sum, s1)
//Adder for bit 3
val Adder3 = Module(new FullAdder())
Adder3.io.a := io.A(3)
Adder3.io.b := io.B(3)
Adder3.io.cin := Adder2.io.cout
// io.Sum := Cat(Adder3.io.sum, s2).asUInt
io.Sum := Cat(Adder3.io.sum, Adder2.io.sum, Adder1.io.sum, Adder0.io.sum)
io.Cout := Adder3.io.cout
}
 
object Adder4Main {
def main(args: Array[String]): Unit = {
chisel3.Driver.execute(Array("--target-dir", "generated/Adder4"), () => new Adder4)
// chisel3.Driver.execute(args, () => new FullAdder)
}
}