diff --git a/py65/tests/devices/test_mpu6502.py b/py65/tests/devices/test_mpu6502.py
index 9832a0a..9ce3505 100644
--- a/py65/tests/devices/test_mpu6502.py
+++ b/py65/tests/devices/test_mpu6502.py
@@ -76,7 +76,7 @@ class Common6502Tests:
         self.assertEqual(0x01, mpu.a)
         self.assertEqual(0, mpu.p & mpu.NEGATIVE)
         self.assertEqual(0, mpu.p & mpu.ZERO)
-        self.assertNotEquals(mpu.CARRY, mpu.p & mpu.CARRY)
+        self.assertNotEqual(mpu.CARRY, mpu.p & mpu.CARRY)
 
     def test_adc_bcd_off_absolute_carry_clear_in_no_carry_clear_out(self):
         mpu = self._make_mpu()
@@ -193,7 +193,7 @@ class Common6502Tests:
         self.assertEqual(0x01, mpu.a)
         self.assertEqual(0, mpu.p & mpu.NEGATIVE)
         self.assertEqual(0, mpu.p & mpu.ZERO)
-        self.assertNotEquals(mpu.CARRY, mpu.p & mpu.CARRY)
+        self.assertNotEqual(mpu.CARRY, mpu.p & mpu.CARRY)
 
     def test_adc_bcd_off_zp_carry_clear_in_no_carry_clear_out(self):
         mpu = self._make_mpu()
@@ -308,7 +308,7 @@ class Common6502Tests:
         self.assertEqual(0x01, mpu.a)
         self.assertEqual(0, mpu.p & mpu.NEGATIVE)
         self.assertEqual(0, mpu.p & mpu.ZERO)
-        self.assertNotEquals(mpu.CARRY, mpu.p & mpu.CARRY)
+        self.assertNotEqual(mpu.CARRY, mpu.p & mpu.CARRY)
 
     def test_adc_bcd_off_immediate_carry_clear_in_no_carry_clear_out(self):
         mpu = self._make_mpu()
@@ -469,7 +469,7 @@ class Common6502Tests:
         self.assertEqual(0x01, mpu.a)
         self.assertEqual(0, mpu.p & mpu.NEGATIVE)
         self.assertEqual(0, mpu.p & mpu.ZERO)
-        self.assertNotEquals(mpu.CARRY, mpu.p & mpu.CARRY)
+        self.assertNotEqual(mpu.CARRY, mpu.p & mpu.CARRY)
 
     def test_adc_bcd_off_abs_x_carry_clear_in_no_carry_clear_out(self):
         mpu = self._make_mpu()
@@ -591,7 +591,7 @@ class Common6502Tests:
         self.assertEqual(0x01, mpu.a)
         self.assertEqual(0, mpu.p & mpu.NEGATIVE)
         self.assertEqual(0, mpu.p & mpu.ZERO)
-        self.assertNotEquals(mpu.CARRY, mpu.p & mpu.CARRY)
+        self.assertNotEqual(mpu.CARRY, mpu.p & mpu.CARRY)
 
     def test_adc_bcd_off_abs_y_carry_clear_in_no_carry_clear_out(self):
         mpu = self._make_mpu()
@@ -713,7 +713,7 @@ class Common6502Tests:
         self.assertEqual(0x01, mpu.a)
         self.assertEqual(0, mpu.p & mpu.NEGATIVE)
         self.assertEqual(0, mpu.p & mpu.ZERO)
-        self.assertNotEquals(mpu.CARRY, mpu.p & mpu.CARRY)
+        self.assertNotEqual(mpu.CARRY, mpu.p & mpu.CARRY)
 
     def test_adc_bcd_off_zp_x_carry_clear_in_no_carry_clear_out(self):
         mpu = self._make_mpu()
@@ -843,7 +843,7 @@ class Common6502Tests:
         self.assertEqual(0x01, mpu.a)
         self.assertEqual(0, mpu.p & mpu.NEGATIVE)
         self.assertEqual(0, mpu.p & mpu.ZERO)
-        self.assertNotEquals(mpu.CARRY, mpu.p & mpu.CARRY)
+        self.assertNotEqual(mpu.CARRY, mpu.p & mpu.CARRY)
 
     def test_adc_bcd_off_ind_indexed_carry_clear_in_no_carry_clear_out(self):
         mpu = self._make_mpu()
@@ -987,7 +987,7 @@ class Common6502Tests:
         self.assertEqual(0x01, mpu.a)
         self.assertEqual(0, mpu.p & mpu.NEGATIVE)
         self.assertEqual(0, mpu.p & mpu.ZERO)
-        self.assertNotEquals(mpu.CARRY, mpu.p & mpu.CARRY)
+        self.assertNotEqual(mpu.CARRY, mpu.p & mpu.CARRY)
 
     def test_adc_bcd_off_indexed_ind_carry_clear_in_no_carry_clear_out(self):
         mpu = self._make_mpu()
@@ -5544,7 +5544,7 @@ class Common6502Tests:
                           py65.assembler.Assembler.Addressing)
         mpu = self._make_mpu()
         for name, mode in mpu.disassemble:
-            self.assert_(mode in valid_modes)
+            self.assertTrue(mode in valid_modes)
 
     def test_brk_interrupt(self):
         mpu = self._make_mpu()
@@ -5647,7 +5647,7 @@ class MPUTests(unittest.TestCase, Common6502Tests):
 
     def test_repr(self):
         mpu = self._make_mpu()
-        self.assert_("6502" in repr(mpu))
+        self.assertTrue("6502" in repr(mpu))
 
     def _get_target_class(self):
         return py65.devices.mpu6502.MPU
diff --git a/py65/tests/devices/test_mpu65c02.py b/py65/tests/devices/test_mpu65c02.py
index 8da97f6..851d3b7 100644
--- a/py65/tests/devices/test_mpu65c02.py
+++ b/py65/tests/devices/test_mpu65c02.py
@@ -9,7 +9,7 @@ class MPUTests(unittest.TestCase, Common6502Tests):
 
     def test_repr(self):
         mpu = self._make_mpu()
-        self.assert_('65C02' in repr(mpu))
+        self.assertTrue('65C02' in repr(mpu))
 
     # ADC Zero Page, Indirect
 
@@ -44,7 +44,7 @@ class MPUTests(unittest.TestCase, Common6502Tests):
         self.assertEqual(0x01, mpu.a)
         self.assertEqual(0, mpu.p & mpu.NEGATIVE)
         self.assertEqual(0, mpu.p & mpu.ZERO)
-        self.assertNotEquals(mpu.CARRY, mpu.p & mpu.CARRY)
+        self.assertNotEqual(mpu.CARRY, mpu.p & mpu.CARRY)
 
     def test_adc_bcd_off_zp_ind_carry_clear_in_no_carry_clear_out(self):
         mpu = self._make_mpu()
diff --git a/py65/tests/utils/test_hexdump.py b/py65/tests/utils/test_hexdump.py
index 7723f91..835ea55 100644
--- a/py65/tests/utils/test_hexdump.py
+++ b/py65/tests/utils/test_hexdump.py
@@ -31,7 +31,7 @@ class HexdumpLoaderTests(unittest.TestCase):
             self.fail()
         except ValueError as exc:
             msg = 'Start address was not found in data'
-            self.assert_(str(exc).startswith('Start address'))
+            self.assertTrue(str(exc).startswith('Start address'))
 
     def test_raises_when_start_address_is_invalid(self):
         text = 'oops: aa bb cc'