diff --git a/pyasm/asm_tests/test_harness b/pyasm/asm_tests/test_harness
index 3fdee7b..fecd6cc 100755
--- a/pyasm/asm_tests/test_harness
+++ b/pyasm/asm_tests/test_harness
@@ -35,6 +35,34 @@ BlockloaderSize = 8 * 16        # 8 lines of 16 bytes
 HighBitMask = 0100000
 
 
+def eval_expr(dot, expr):
+    """Evaluate an expression that may contain '.'.
+
+    dot   the current value of 'dot'
+    expr  the expression string to avaluate
+
+    Returns the value of the expression.
+    Raises ArithmeticError if something is wrong.
+    """
+
+    # replace any "." value with "dot" defined in the symbol table
+    expr = string.replace(expr, '.', 'DOT')
+
+    # evaluate the expression
+    globs = {'DOT': dot}        # passed environment contains 'DOT'
+    try:
+        result = eval(expr, globs)
+    except (TypeError, NameError) as e:
+        Undefined = e.message
+        if 'is not defined' in e.message:
+            Undefined = e.message[len("name '"):-len("' is not defined")]
+            msg = "Test expression has '%s' undefined" % Undefined
+            raise ArithmeticError(msg)
+        msg = "Test expression has an error"
+        raise ArithmeticError(msg)
+
+    return result
+
 def oct_dec_int(s):
     """Convert string 's' to binary integer."""
 
@@ -187,7 +215,7 @@ def test_file(filename):
         else:
             # have label, $n or octal/decimal?
             # set 'dot' either way
-            (label, value) = test.split()
+            (label, value) = test.split(' ', 1)
             if label[0] == '$':
                 org_num = int(label[1:])
                 try:
@@ -200,7 +228,9 @@ def test_file(filename):
             else:
                 address = oct_dec_int(label)
                 dot = address
-        value = oct_dec_int(value)
+
+        # evaluate the value field
+        value = eval_expr(dot, value)
 
         if address is None:
             warn("File '%s' has label '%s' with bad ORG number"
@@ -224,9 +254,6 @@ def test_file(filename):
 
         dot += 1
 
-#    if errors:
-#        print("File '%s' had errors" % filename)
-
 def warn(msg):
     """Print error message and continue."""
 
diff --git a/pyasm/asm_tests/tests/aalpha b/pyasm/asm_tests/tests/aalpha
index 63eb235..3834eb2 100644
--- a/pyasm/asm_tests/tests/aalpha
+++ b/pyasm/asm_tests/tests/aalpha
@@ -1,4 +1,4 @@
-; test file
+; test file, old syntax tests
         org     0100
         law     1
         hlt
diff --git a/pyasm/asm_tests/tests/aalpha.NEW b/pyasm/asm_tests/tests/aalpha.NEW
index 4b05e2e..dfacfad 100644
--- a/pyasm/asm_tests/tests/aalpha.NEW
+++ b/pyasm/asm_tests/tests/aalpha.NEW
@@ -1,7 +1,7 @@
-; test file
+; test file, new syntax
         org     0100
         law     1
         hlt
         end
-;|$1   004001
+;|$1   004000 + 1
 ;|     000000
diff --git a/pyasm/asm_tests/tests/alpha.NEW b/pyasm/asm_tests/tests/alpha.NEW
new file mode 100644
index 0000000..fe21ce6
--- /dev/null
+++ b/pyasm/asm_tests/tests/alpha.NEW
@@ -0,0 +1,9 @@
+; deliberate errors at lines 7 and 9
+        org     0100
+        law     1
+        hlt
+        end
+
+;|$1   004000 + 2   ; is actually 004001
+;|     000000
+;|     000001       ; address outside block
diff --git a/pyasm/asm_tests/tests/beta.NEW b/pyasm/asm_tests/tests/beta.NEW
new file mode 100644
index 0000000..64c52f8
--- /dev/null
+++ b/pyasm/asm_tests/tests/beta.NEW
@@ -0,0 +1,12 @@
+; test file with two ORG blocks
+        org     0100
+        law     1
+        hlt
+        org     0200
+        law     2
+        hlt
+        end
+;|$1   004000 + 1
+;|     000000
+;|$2   004000 + 2
+;|     000000
diff --git a/pyasm/asm_tests/tests/delta b/pyasm/asm_tests/tests/delta.NEW
similarity index 75%
rename from pyasm/asm_tests/tests/delta
rename to pyasm/asm_tests/tests/delta.NEW
index c3c0d0e..a9a2b78 100644
--- a/pyasm/asm_tests/tests/delta
+++ b/pyasm/asm_tests/tests/delta.NEW
@@ -4,5 +4,5 @@
         hlt
         end
 
-;|$2   004001       ; bad ORG number
+;|$3   004001       ; bad ORG number
 ;|     000000
diff --git a/pyasm/asm_tests/tests/kappa.NEW b/pyasm/asm_tests/tests/kappa.NEW
new file mode 100644
index 0000000..a306c3b
--- /dev/null
+++ b/pyasm/asm_tests/tests/kappa.NEW
@@ -0,0 +1,14 @@
+; test file with two adjacent ORG blocks
+        org     0100
+        law     1
+        hlt
+
+        org     0102
+        law     2
+        hlt
+        end
+
+;|$1   004000 + 1
+;|     000000
+;|     004000 + 2
+;|     000000