bin spec and usage

example/manual/bin2gray.py

@@ -25,7 +25,7 @@ def testBench(width):
         for i in range(2**width):
             B.next = intbv(i)
             yield delay(10)
-            print "B: %s | G: %s" % (bin(B.val, width), bin(G.val, width))
+            print "B: " + bin(B.val, width) + "| G: " + bin(G.val, width)
 
     return (dut, stimulus())
 

myhdl/intbv_spec.txt

@@ -77,5 +77,9 @@ separate type.
   addition, literal bit strings are accepted in concatenations, just as
   they are in intbv constructors.
 
+* intbv has a bin(width) method that returns a binary string
+  representation. The optional width specifies the desired string
+  width: padding of the sign-bit is used.
+
 * intbv supports the iterator protocol to iterate on its bits; again,
   this requires a known length.