diff --git a/fpgalib/test/test_dac.py b/fpgalib/test/test_dac.py
index b4ead8d5..ba67b8af 100644
--- a/fpgalib/test/test_dac.py
+++ b/fpgalib/test/test_dac.py
@@ -37,59 +37,67 @@ def test_make_jump_table(self):
         self.dac.make_jump_table(entries)
         # we made it this far and we're feeling pretty good about it
 
-    def test_catch_bad_jump_table(self):
-        """Test jump table commands that are executed too frequently"""
-
-        # from_addr of 16 followed by 20 are too close together
-        bad_jump_args = [
+    def test_catch_nop_nop_too_close(self):
+        entries = self.make_entries([
             ('NOP', [16]),
             ('NOP', [20]),
             ('END', [400])
-        ]
+        ])
+        with pytest.raises(ValueError):
+                self.dac.make_jump_table(entries)
+
+    def test_catch_jump_iterated_nop_too_close(self):
 
-        # from addr of 16 is followed by from addr of 20
-        bad_jump_args_2 = [
+        entries = self.make_entries([
             ('JUMP', [32, 16, 1]),
             ('NOP', [20]),
             ('END', [400])
-        ]
+        ])
+        with pytest.raises(ValueError):
+            self.dac.make_jump_table(entries)
+
+    def test_catch_jump_back_too_close(self):
+
+        entries = self.make_entries([
+            ('NOP', [32]),
+            ('JUMP', [100, 28, 0]),
+            ('END', [400])
+        ])
+        with pytest.raises(ValueError):
+            self.dac.make_jump_table(entries)
+
+    def test_catch_idle_end_too_close(self):
 
         # from addr of 32 is followed by from addr of 36 (even though IDLE?)
-        bad_jump_args_3 = [
+        entries = self.make_entries([
             ('IDLE', [32, 200]),
             ('END', [36])
-        ]
-
-        for args in [bad_jump_args, bad_jump_args_2, bad_jump_args_3]:
-            entries = self.make_entries(args)
-            with pytest.raises(ValueError):
-                self.dac.make_jump_table(entries)
+        ])
+        with pytest.raises(ValueError):
+            self.dac.make_jump_table(entries)
 
-    def test_catch_bad_jump_table_edge(self):
+    def test_nop_nop_1_clk_too_close(self):
         """Test a table that executes commands 1 clock cycle too frequently"""
 
         from_addr = self.dac.JT_MIN_FROM_ADDR * 4
-        bad_jump_args = [
+        entries = self.make_entries([
             ('NOP', [from_addr]),
             ('NOP', [from_addr +
                      (self.dac.JT_MIN_CLK_CYCLES_BETWEEN_OPCODES - 1) * 4]),
             ('END', [400])
-        ]
+        ])
 
-        entries = self.make_entries(bad_jump_args)
         with pytest.raises(ValueError):
-                self.dac.make_jump_table(entries)
+            self.dac.make_jump_table(entries)
 
+    def test_nop_nop_min_clk_ok(self):
         from_addr = self.dac.JT_MIN_FROM_ADDR * 4
-        bad_jump_args = [
+        _ = self.make_entries([
             ('NOP', [from_addr]),
             ('NOP', [from_addr +
                      self.dac.JT_MIN_CLK_CYCLES_BETWEEN_OPCODES * 4]),
             ('END', [400])
-        ]
-
-        _ = self.make_entries(bad_jump_args)
-
+        ])
 
 if __name__ == '__main__':
     pytest.main(['-v', __file__])