From c5f9ea3133ef363ff8944e17d94fea79767b6bed Mon Sep 17 00:00:00 2001 From: Jim Lawson Date: Wed, 6 Jul 2016 10:01:23 -0700 Subject: Rename "Chisel" to "chisel3" (only git mv). --- src/main/scala/chisel3/util/Reg.scala | 55 +++++++++++++++++++++++++++++++++++ 1 file changed, 55 insertions(+) create mode 100644 src/main/scala/chisel3/util/Reg.scala (limited to 'src/main/scala/chisel3/util/Reg.scala') diff --git a/src/main/scala/chisel3/util/Reg.scala b/src/main/scala/chisel3/util/Reg.scala new file mode 100644 index 00000000..6584a4bf --- /dev/null +++ b/src/main/scala/chisel3/util/Reg.scala @@ -0,0 +1,55 @@ +// See LICENSE for license details. + +/** Variations and helpers for registers. + */ + +package Chisel + +object RegNext { + + def apply[T <: Data](next: T): T = Reg[T](null.asInstanceOf[T], next, null.asInstanceOf[T]) + + def apply[T <: Data](next: T, init: T): T = Reg[T](null.asInstanceOf[T], next, init) + +} + +object RegInit { + + def apply[T <: Data](init: T): T = Reg[T](null.asInstanceOf[T], null.asInstanceOf[T], init) + +} + +/** A register with an Enable signal */ +object RegEnable +{ + def apply[T <: Data](updateData: T, enable: Bool): T = { + val r = Reg(updateData) + when (enable) { r := updateData } + r + } + def apply[T <: Data](updateData: T, resetData: T, enable: Bool): T = { + val r = RegInit(resetData) + when (enable) { r := updateData } + r + } +} + +/** Returns the n-cycle delayed version of the input signal. + */ +object ShiftRegister +{ + /** @param in input to delay + * @param n number of cycles to delay + * @param en enable the shift */ + def apply[T <: Data](in: T, n: Int, en: Bool = Bool(true)): T = + { + // The order of tests reflects the expected use cases. + if (n == 1) { + RegEnable(in, en) + } else if (n != 0) { + RegNext(apply(in, n-1, en)) + } else { + in + } + } +} -- cgit v1.2.3