在SpinalHDL中使用之前已有的Verilog等代碼的時候需要將這些代碼包在一個BlackBox里面，但是如果這些代碼里面有時鐘和復位，我們需要怎么將時鐘和復位端口和SpinalHDL中已有的時鐘域連接起來呢？

當BlackBox中只有一個時鐘的時候可以直接使用mapClockDomain完成時鐘信號和復位信號的賦值。在mapClockDomain中如果沒有指定時鐘域的話就采用的是默認時鐘域。

import spinal.core._
import spinal.lib._
class BK extends BlackBox{
    val clka = in Bool()
    val rsta = in Bool()
    val din = in Bool()
    val dout = out Bool()
    mapClockDomain(clock = clka, reset = rsta)
}
class TestBlackBox extends Component {
    val din = in Bool()
    val dout = out Bool()
    val bk = new BK
    bk.din <> din
    bk.dout <> dout
}
object TestBlackBox extends App{
    SpinalVerilog(new TestBlackBox)
}

當有兩個時鐘域的時候，就需要把時鐘域給指定一下了，在下面代碼中將時鐘域通過參數的方式傳了進來。

import spinal.core._
import spinal.lib._
class BK(clockDomaina: ClockDomain, clockDomainb: ClockDomain) extends BlackBox{
    val clka = in Bool()
    val rsta = in Bool()
    val clkb = in Bool()
    val rstb = in Bool()
    val din = in Bool()
    val dout = out Bool()
    mapClockDomain(clockDomaina,clock = clka, reset = rsta)
    mapClockDomain(clockDomainb,clock = clkb, reset = rstb)
}
class TestBlackBox extends Component {
    val din = in Bool()
    val dout = out Bool()
    val clkb = in Bool()
    val resetb = in Bool()
    val clockDomainb = ClockDomain(clock = clkb,reset = resetb)
    val bk = new BK(this.clockDomain,clockDomainb)//默認時鐘域和新建的時鐘域b
    bk.din <> din
    bk.dout <> dout
}
object TestBlackBox extends App{
    SpinalVerilog(new TestBlackBox)
}

因為在SpinalHDL中默認時鐘域是高復位的，但是我們已有的IP可能是低復位的，這個時候就需要在mapClockDomain中指定一下復位信號是HIGH還是LOW。在下面代碼中就將時鐘域b下面的復位指定為低復位。

import spinal.core._
import spinal.lib._
class BK(clockDomaina: ClockDomain, clockDomainb: ClockDomain) extends BlackBox{
    val clka = in Bool()
    val rsta = in Bool()
    val clkb = in Bool()
    val rstb = in Bool()
    val din = in Bool()
    val dout = out Bool()
    mapClockDomain(clockDomaina,clock = clka, reset = rsta)
    mapClockDomain(clockDomainb,clock = clkb, reset = rstb, resetActiveLevel = LOW)
}
class TestBlackBox extends Component {
    val din = in Bool()
    val dout = out Bool()
    val clkb = in Bool()
    val resetb = in Bool()
    val clockDomainb = ClockDomain(clock = clkb,reset = resetb)
    val bk = new BK(this.clockDomain,clockDomainb)
    bk.din <> din
    bk.dout <> dout
}
object TestBlackBox extends App{
    SpinalVerilog(new TestBlackBox)
}

以上三種情況應該足夠應對一般情況下BlackBox的時鐘域的賦值了。

審核編輯：湯梓紅