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-rw-r--r--src/main/scala/chisel3/util/LFSR.scala26
1 files changed, 26 insertions, 0 deletions
diff --git a/src/main/scala/chisel3/util/LFSR.scala b/src/main/scala/chisel3/util/LFSR.scala
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+++ b/src/main/scala/chisel3/util/LFSR.scala
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+// See LICENSE for license details.
+
+/** LFSRs in all shapes and sizes.
+ */
+
+package chisel3.util
+
+import chisel3._
+//import chisel3.core.ExplicitCompileOptions.Strict
+
+// scalastyle:off magic.number
+object LFSR16 {
+ /** Generates a 16-bit linear feedback shift register, returning the register contents.
+ * May be useful for generating a pseudorandom sequence.
+ *
+ * @param increment optional control to gate when the LFSR updates.
+ */
+ def apply(increment: Bool = Bool(true)): UInt = {
+ val width = 16
+ val lfsr = Reg(init=UInt(1, width))
+ when (increment) { lfsr := Cat(lfsr(0)^lfsr(2)^lfsr(3)^lfsr(5), lfsr(width-1,1)) }
+ lfsr
+ }
+}
+// scalastyle:on magic.number
+