package top_count import spinal.core._ case class counter() extends Component { val io = new Bundle { val en_i = in Bool() val cnt_o = out UInt(4 bits) } // The counter register val cnt = Reg(UInt(4 bits)) init 0 when (io.en_i) { cnt := cnt + 1 } // Map the register content to the output io.cnt_o := cnt }