diff --git a/asl_xdsl/dialects/asl.py b/asl_xdsl/dialects/asl.py
index 0736516..7d7c58f 100644
--- a/asl_xdsl/dialects/asl.py
+++ b/asl_xdsl/dialects/asl.py
@@ -64,10 +64,8 @@ class BitVectorType(ParametrizedAttribute, TypeAttribute):
 
     width: ParameterDef[builtin.IntAttr]
 
-    def __init__(self, width: int | builtin.IntAttr):
-        if isinstance(width, int):
-            width = builtin.IntAttr(width)
-        super().__init__([width])
+    def __init__(self, width: int):
+        super().__init__([builtin.IntAttr(width)])
 
     @classmethod
     def parse_parameters(cls, parser: AttrParser) -> Sequence[Attribute]:
@@ -91,11 +89,11 @@ class BitVectorAttr(ParametrizedAttribute):
     name = "asl.bits_attr"
 
     value: ParameterDef[builtin.IntAttr]
-    width: ParameterDef[builtin.IntAttr]
+    type: ParameterDef[BitVectorType]
 
     def maximum_value(self) -> int:
         """Return the maximum value that can be represented."""
-        return (1 << self.width.data) - 1
+        return (1 << self.type.width.data) - 1
 
     @staticmethod
     def normalize_value(value: int, width: int) -> int:
@@ -103,20 +101,15 @@ def normalize_value(value: int, width: int) -> int:
         max_value = 1 << width
         return ((value % max_value) + max_value) % max_value
 
-    def __init__(self, value: int | builtin.IntAttr, width: int | builtin.IntAttr):
-        if isinstance(value, int):
-            value = builtin.IntAttr(value)
-        if isinstance(width, int):
-            width = builtin.IntAttr(width)
-
-        value_int = value.data
-        value = builtin.IntAttr(self.normalize_value(value_int, width.data))
-        super().__init__([value, width])
+    def __init__(self, value: int, type: BitVectorType):
+        value = self.normalize_value(value, type.width.data)
+        super().__init__([builtin.IntAttr(value), type])
 
     def _verify(self) -> None:
         if self.value.data < 0 or self.value.data >= self.maximum_value():
             raise VerifyException(
-                f"Value {self.value.data} is out of range for width {self.width.data}"
+                f"Value {self.value.data} is out of range "
+                f"for width {self.type.width.data}"
             )
 
     @classmethod
@@ -125,7 +118,7 @@ def parse_parameters(cls, parser: AttrParser) -> Sequence[Attribute]:
         parser.parse_characters("<")
         value = builtin.IntAttr(parser.parse_integer())
         parser.parse_characters(":")
-        width = builtin.IntAttr(parser.parse_integer())
+        width = parser.parse_attribute()
         parser.parse_characters(">")
         return [value, width]
 
@@ -134,7 +127,7 @@ def print_parameters(self, printer: Printer) -> None:
         printer.print("<")
         printer.print(self.value.data)
         printer.print(" : ")
-        printer.print(self.width.data)
+        printer.print(self.type.width.data)
         printer.print(">")
 
 
@@ -147,12 +140,10 @@ class ConstantBoolOp(IRDLOperation):
     value = prop_def(BoolAttr)
     res = result_def(BoolType())
 
-    def __init__(self, value: bool | BoolAttr, attr_dict: Mapping[str, Attribute] = {}):
-        if isinstance(value, bool):
-            value = BoolAttr(value)
+    def __init__(self, value: bool, attr_dict: Mapping[str, Attribute] = {}):
         super().__init__(
             result_types=[BoolType()],
-            properties={"value": value},
+            properties={"value": BoolAttr(value)},
             attributes=attr_dict,
         )
 
@@ -206,8 +197,50 @@ def print(self, printer: Printer) -> None:
             printer.print_attr_dict(self.attributes)
 
 
+@irdl_op_definition
+class ConstantBitVectorOp(IRDLOperation):
+    """A constant bit vector operation."""
+
+    name = "asl.constant_bits"
+
+    value = prop_def(BitVectorAttr)
+    res = result_def(BitVectorType)
+
+    def __init__(
+        self,
+        value: BitVectorAttr,
+        attr_dict: Mapping[str, Attribute] = {},
+    ) -> None:
+        super().__init__(
+            result_types=[value.type],
+            properties={"value": value},
+            attributes=attr_dict,
+        )
+
+    @classmethod
+    def parse(cls, parser: Parser) -> ConstantBitVectorOp:
+        """Parse the operation."""
+        value = parser.parse_integer()
+        parser.parse_characters(":")
+
+        type = parser.parse_attribute()
+        if not isinstance(type, BitVectorType):
+            parser.raise_error(f"Expected bit vector type, got {type}")
+
+        value = BitVectorAttr(value, type)
+        attr_dict = parser.parse_optional_attr_dict()
+        return ConstantBitVectorOp(value, attr_dict)
+
+    def print(self, printer: Printer) -> None:
+        """Print the operation."""
+        printer.print(" ", self.value.value.data, " : ", self.res.type)
+        if self.attributes:
+            printer.print(" ")
+            printer.print_attr_dict(self.attributes)
+
+
 ASLDialect = Dialect(
     "asl",
-    [ConstantBoolOp, ConstantIntOp],
+    [ConstantBoolOp, ConstantIntOp, ConstantBitVectorOp],
     [BoolType, BoolAttr, IntegerType, BitVectorType, BitVectorAttr],
 )
diff --git a/tests/filecheck/dialects/asl/constant_ops.mlir b/tests/filecheck/dialects/asl/constant_ops.mlir
index 23a9107..a015c45 100644
--- a/tests/filecheck/dialects/asl/constant_ops.mlir
+++ b/tests/filecheck/dialects/asl/constant_ops.mlir
@@ -5,10 +5,13 @@ builtin.module {
     %false = asl.constant_bool false {attr_dict}
 
     %fourty_two = asl.constant_int 42 {attr_dict}
+
+    %fourty_two_bits = asl.constant_bits 42 : !asl.bits<32> {attr_dict}
 }
 
 // CHECK:       builtin.module {
 // CHECK-NEXT:    %true = asl.constant_bool true {"attr_dict"}
 // CHECK-NEXT:    %false = asl.constant_bool true {"attr_dict"}
 // CHECK-NEXT:    %fourty_two = asl.constant_int 42 {"attr_dict"}
+// CHECK-NEXT:    %fourty_two_bits = asl.constant_bits 42 : !asl.bits<32> {"attr_dict"}
 // CHECK-NEXT:  }
diff --git a/tests/filecheck/dialects/asl/types_attrs.mlir b/tests/filecheck/dialects/asl/types_attrs.mlir
index f9495b5..88b1c2f 100644
--- a/tests/filecheck/dialects/asl/types_attrs.mlir
+++ b/tests/filecheck/dialects/asl/types_attrs.mlir
@@ -7,7 +7,7 @@ builtin.module {
     "test.op"() {int_type = !asl.int} : () -> ()
 
     "test.op"() {bits_type = !asl.bits<32>} : () -> ()
-    "test.op"() {bits_attr = #asl.bits_attr<42 : 32>} : () -> ()
+    "test.op"() {bits_attr = #asl.bits_attr<42 : !asl.bits<32>>} : () -> ()
 }
 
 // CHECK:         "test.op"() {"bool_type" = !asl.bool} : () -> ()