Change keyboard configuration to match other emulators.

README.md

@@ -217,27 +217,22 @@ customize the operation of the emulator.  The Chip 8 has 16 keys:
 ### Keys
 
 The original Chip 8 had a keypad with the numbered keys 0 - 9 and A - F (16
-keys in total). Without any modifications to the emulator, the keys are mapped
-as follows:
-
-| Chip 8 Key | Keyboard Key |
-| :--------: | :----------: |
-| `1`        | `4`          |
-| `2`        | `5`          |
-| `3`        | `6`          |
-| `4`        | `7`          |
-| `5`        | `R`          |
-| `6`        | `T`          |
-| `7`        | `Y`          |
-| `8`        | `U`          |
-| `9`        | `F`          |
-| `0`        | `G`          |
-| `A`        | `H`          |
-| `B`        | `J`          |
-| `C`        | `V`          |
-| `D`        | `B`          |
-| `E`        | `N`          |
-| `F`        | `M`          |
+keys in total). The original key configuration was as follows:
+
+
+| `1` | `2` | `3` | `C` |
+|-----|-----|-----|-----|
+| `4` | `5` | `6` | `D` |
+| `7` | `8` | `9` | `E` |
+| `A` | `0` | `B` | `F` |
+
+The Chip8 emulator maps them to the following keyboard keys by default:
+
+| `1` | `2` | `3` | `4` |
+|-----|-----|-----|-----|
+| `Q` | `W` | `E` | `R` |
+| `A` | `S` | `D` | `F` |
+| `Z` | `X` | `C` | `V` |
 
 If you wish to configure a different key-mapping, simply change the `KEY_MAPPINGS` variable
 in the configuration file to reflect the mapping that you want. The
@@ -249,9 +244,9 @@ list of all the valid constants for keyboard key values.
 In addition to the key mappings specified in the configuration file, there are additional
 keys that impact the execution of the emulator.
 
-| Keyboard Key | Effect |
-| :----------: | ------ |
-| `ESC`        | Quits the emulator             |
+| Keyboard Key | Effect             |
+| :----------: |--------------------|
+| `ESC`        | Quits the emulator |
 
 
 ## ROM Compatibility

chip8/config.py

@@ -21,22 +21,22 @@
 
 # Sets which keys on the keyboard map to the Chip 8 keys
 KEY_MAPPINGS = {
-    0x0: pygame.K_g,
-    0x1: pygame.K_4,
-    0x2: pygame.K_5,
-    0x3: pygame.K_6,
-    0x4: pygame.K_7,
-    0x5: pygame.K_r,
-    0x6: pygame.K_t,
-    0x7: pygame.K_y,
-    0x8: pygame.K_u,
-    0x9: pygame.K_f,
-    0xA: pygame.K_h,
-    0xB: pygame.K_j,
-    0xC: pygame.K_v,
-    0xD: pygame.K_b,
-    0xE: pygame.K_n,
-    0xF: pygame.K_m,
+    0x0: pygame.K_x,
+    0x1: pygame.K_1,
+    0x2: pygame.K_2,
+    0x3: pygame.K_3,
+    0x4: pygame.K_q,
+    0x5: pygame.K_w,
+    0x6: pygame.K_e,
+    0x7: pygame.K_a,
+    0x8: pygame.K_s,
+    0x9: pygame.K_d,
+    0xA: pygame.K_z,
+    0xB: pygame.K_c,
+    0xC: pygame.K_4,
+    0xD: pygame.K_r,
+    0xE: pygame.K_f,
+    0xF: pygame.K_v,
 }
 
 # The font file to use

chip8/cpu.py

@@ -84,7 +84,7 @@ def reset(self):
         self.rpl = [0] * NUM_REGISTERS
 
 
-class Chip8CPU(object):
+class Chip8CPU:
     """
     A class to emulate a Chip 8 CPU. There are several good resources out on
     the web that describe the internals of the Chip 8 CPU. For example:

test/test_chip8cpu.py

@@ -533,7 +533,7 @@ def test_operation_9E_pc_skips_if_key_pressed(self):
         self.cpu.registers.v[0] = 1
         self.cpu.registers.pc = 0
         result_table = [False] * 512
-        result_table[pygame.K_4] = True
+        result_table[pygame.K_1] = True
         with mock.patch("pygame.key.get_pressed", return_value=result_table) as key_mock:
             self.cpu.keyboard_routines()
             self.assertTrue(key_mock.asssert_called)
@@ -564,7 +564,7 @@ def test_operation_A1_pc_does_not_skip_if_key_pressed(self):
         self.cpu.registers.v[0] = 1
         self.cpu.registers.pc = 0
         result_table = [False] * 512
-        result_table[pygame.K_4] = True
+        result_table[pygame.K_1] = True
         with mock.patch("pygame.key.get_pressed", return_value=result_table) as key_mock:
             self.cpu.keyboard_routines()
             self.assertTrue(key_mock.asssert_called)
@@ -769,7 +769,7 @@ def test_wait_for_keypress(self):
         self.cpu.operand = 0x0
         with mock.patch("pygame.event.wait", return_value=event_mock):
             result_table = [False] * 512
-            result_table[pygame.K_4] = True
+            result_table[pygame.K_1] = True
             with mock.patch("pygame.key.get_pressed", return_value=result_table):
                 self.cpu.wait_for_keypress()
                 self.assertEqual(0x1, self.cpu.registers.v[0])