diff --git a/python/samples/flash.py b/python/samples/flash.py
index 6134cfe..5248c79 100644
--- a/python/samples/flash.py
+++ b/python/samples/flash.py
@@ -8,14 +8,15 @@
 
 def hexdump(s):
     def toprint(c):
-        if 32 <= ord(c) < 127:
-            return c
+        if 32 <= c < 127:
+            return chr(c)
         else:
             return "."
     def hexline(s):
-        return (" ".join(["%02x" % ord(c) for c in s]).ljust(49) +
+        bb = struct.unpack("16B", s)
+        return (" ".join(["%02x" % c for c in bb]).ljust(49) +
                 "|" +
-                "".join([toprint(c) for c in s]).ljust(16) +
+                "".join([toprint(c) for c in bb]).ljust(16) +
                 "|")
     return "\n".join([hexline(s[i:i+16]) for i in range(0, len(s), 16)])
 
@@ -38,6 +39,7 @@ def pattern(n):
     optdict = dict(optlist)
 
     s = SPIDriver(optdict.get('-h', "/dev/ttyUSB0"))
+    s.unsel()
 
     while True:
         s.sel()               # start command