spell check

myhdl/Signal_spec.txt

@@ -35,10 +35,10 @@ In the following, a "sig" denotes an instance of the Signal class.
 * A sig should have a read-only attribute 'val' that represents its
   current value.
 
-* The Signal contructor should have one mandatory parameter 'val' to
+* The Signal constructor should have one mandatory parameter 'val' to
   initialize its current value and future value.
 
-* The Signal contructor should have an optional parameter 'delay' to
+* The Signal contractor should have an optional parameter 'delay' to
   specify an initial delay value for the signal. The default value is
   0, meaning no delay.
 
@@ -51,7 +51,7 @@ In the following, a "sig" denotes an instance of the Signal class.
   access. (Read access is required to support mutable values.)
 
 * In principle, any object could be assigned to sig.next; however, for
-  meaningful modelling its type should be "compatible" with the type
+  meaningful modeling its type should be "compatible" with the type
   of the current value. Python's ultra-dynamic nature is not useful in
   this case, and could in fact be the source of hard-to-trace
   bugs. Therefore, there should be a check that the type of the object

myhdl/Simulation_spec.txt

@@ -88,7 +88,7 @@ Specification for the Simulation class
     any of the trigger argument described int this list.
   - a generator. In this case, the generator is dynamically added to
     the list of generators to be run in the timestep. When the
-    generator completes, the orginal generator is triggered.
+    generator completes, the original generator is triggered.
 
 * When there are no further events, the Simulation.run method raises
   the StopSimulation exception.

myhdl/intbv_spec.txt

@@ -75,7 +75,7 @@ separate type.
   by an indexing or slicing operation should remember how many bits
   were taken, so that they can be using in concatenations. In
   addition, literal bit strings are accepted in concatenations, just as
-  they are in intbv contructors.
+  they are in intbv constructors.
 
 * intbv supports the iterator protocol to iterate on its bits; again,
   this requires a known length.