Mask range.unit with 0xff when determining the unit.

This avoids crashes like:

  Traceback (most recent call last):
    ...
    File "range.pyx", line 62, in pycomedi.range.Range.__str__
    File "range.pyx", line 70, in pycomedi.range.Range._unit_get
    File "constant.pyx", line 269, in pycomedi.constant._Enum.index_by_value
  KeyError: 256L

when RF_EXTERNAL is set.

diff --git a/pycomedi/range.pyx b/pycomedi/range.pyx
index c3e196a487668489bb098d4042bbf92954d37818..6c05cde7e1dedcb65cf03eb8aff3c2451e31e0ac 100644 (file)
--- a/pycomedi/range.pyx
+++ b/pycomedi/range.pyx
@@ -46,6 +46,10 @@ cdef class Range (_BitwiseOperator):
     >>> r.unit
     <_NamedInt mA>
     """
+    # other data gets packed into the unit unsigned int (e.g RF_EXTERNAL)
+    _uint_all = 0xffffffffL
+    _unit_all = 0xff
+
     def __cinit__(self):
         self.value = -1
 
@@ -67,9 +71,10 @@ cdef class Range (_BitwiseOperator):
         return self.__str__()
 
     def _unit_get(self):
-        return _constant.UNIT.index_by_value(self.range.unit)
+        return _constant.UNIT.index_by_value(self.range.unit & self._unit_all)
     def _unit_set(self, value):
-        self.range.unit = _constant.bitwise_value(value)
+        self.range.unit &= self._uint_all - self._unit_all
+        self.range.unit |= _constant.bitwise_value(value) & self._unit_all
     unit = property(fget=_unit_get, fset=_unit_set)
 
     def _min_get(self):