diff --git a/src/ieu/bmu/bitmanipalu.sv b/src/ieu/bmu/bitmanipalu.sv
index 228b23132..d3094377d 100644
--- a/src/ieu/bmu/bitmanipalu.sv
+++ b/src/ieu/bmu/bitmanipalu.sv
@@ -80,7 +80,10 @@ module bitmanipalu #(parameter WIDTH=32) (
 
   // ZBC Unit
   if (`ZBC_SUPPORTED) begin: zbc
-    zbc #(WIDTH) ZBC(.A, .RevA, .B, .Funct3, .ZBCResult);
+    logic             ZBCSelect;                      // ZBC instruction
+    assign ZBCSelect = BSelect == 2'b11;
+    //assign ZBCSelect = 1'b0;
+    zbc #(WIDTH) ZBC(.A, .RevA, .B, .ZBCSelect, .Funct3, .ZBCResult);
   end else assign ZBCResult = 0;
 
   // ZBB Unit
diff --git a/src/ieu/bmu/zbc.sv b/src/ieu/bmu/zbc.sv
index b173a5f63..30f65258f 100644
--- a/src/ieu/bmu/zbc.sv
+++ b/src/ieu/bmu/zbc.sv
@@ -31,21 +31,23 @@
 
 module zbc #(parameter WIDTH=32) (
   input  logic [WIDTH-1:0] A, RevA, B,       // Operands
+  input  logic             ZBCSelect,        // ZBC instruction
   input  logic [2:0]       Funct3,           // Indicates operation to perform
   output logic [WIDTH-1:0] ZBCResult);       // ZBC result
 
   logic [WIDTH-1:0] ClmulResult, RevClmulResult;
   logic [WIDTH-1:0] RevB;
-  logic [WIDTH-1:0] X, Y;
+  logic [WIDTH-1:0] X, Y, X1;
 
   bitreverse #(WIDTH) brB(B, RevB);
 
-  mux3 #(WIDTH) xmux({RevA[WIDTH-2:0], {1'b0}}, RevA, A, ~Funct3[1:0], X);
-  mux2 #(WIDTH) ymux(RevB, B, ~Funct3[1], Y);
+  mux3 #(WIDTH) xmux1({RevA[WIDTH-2:0], {1'b0}}, RevA, A, ~Funct3[1:0], X1);
+  mux2 #(WIDTH) xmux(X1, '0, ~ZBCSelect, X);
+  mux3 #(WIDTH) ymux(RevB, B, '0, {~ZBCSelect, ~Funct3[1]}, Y);
 
   clmul #(WIDTH) clm(.X, .Y, .ClmulResult);
   
   bitreverse  #(WIDTH) brClmulResult(ClmulResult, RevClmulResult);
 
   mux2 #(WIDTH) zbcresultmux(ClmulResult, RevClmulResult, Funct3[1], ZBCResult);
-endmodule
\ No newline at end of file
+endmodule