PS2 Keyboard Scan Codes
The codes generated by the PS/2 keyboard are called scan codes.
Make codes
When a key is pressed a make code is transmitted. Most make codes are a single byte, apart from some extended keys, such as keypad "/", which consist of a two byte sequence consisting of 0xE0 followed by the key's code.
If a key is held down without being released, the make code for that key is sent continuously, at the defined auto-repeat rate.
Break codes
When a key is released an additional scan code is transmitted called a break code. For the single-byte codes the break code consists of the byte 0xF0 followed by the key's make code. For the extended keys the break codes consist of 0xE0, 0xF0 followed by the key's code.
Pause and Prt Scr keys
The Pause and Prt Scr keys are an exception. The Prt Scr key's make code is four bytes, and its break code is six bytes. The Pause key's make code is 8 bytes and starts with 0xE1, and it has no break code.
Scan Code Set 2
Three scan code sets have been defined, but scan code set 2 is used as the default set by all modern PS/2 keyboards. The codes are shown in the following table in hexadecimal:
| Key | Code: make (break) | Key | Code: make (break) |
| ESC | 76 (F0 76) | K | 42 (F0 42) |
| F1 | 05 (F0 05) | L | 4B (F0 4B) |
| F2 | 06 (F0 06) | ; | 4C (F0 4C) |
| F3 | 04 (F0 04) | ' | 52 (F0 52) |
| F4 | 0C (F0 0C) | Enter | 5A (F0 5A) |
| F5 | 03 (F0 03) | Shift (Left) | 12 (F0 12) |
| F6 | 0B (F0 0B) | Z | 1A (F0 1A) |
| F7 | 83 (F0 83) | X | 22 (F0 22) |
| F8 | 0A (F0 0A) | C | 21 (F0 21) |
| F9 | 01 (F0 01) | V | 2A (F0 2A) |
| F10 | 09 (F0 09) | B | 32 (F0 32) |
| F11 | 78 (F0 78) | N | 31 (F0 31) |
| F12 | 07 (F0 07) | M | 3A (F0 3A) |
| Prt Scr | E0 12 E0 7C (E0 F0 7C E0 F0 12) | , | 41 (F0 41) |
| Scroll Lock | 7E (F0 7E) | . | 49 (F0 49) |
| Pause/Break | E1 14 77 E1 F0 14 E0 77 (None) | / | 4A (F0 4A) |
| ` | 0E (F0 0E) | Shift (Right) | 59 (F0 59) |
| 1 | 16 (F0 16) | Ctrl (left) | 14 (F0 14) |
| 2 | 1E (F0 1E) | Windows (left) | E0 1F (E0 F0 1F) |
| 3 | 26 (F0 26) | Alt (left) | 11 (F0 11) |
| 4 | 25 (F0 25) | Spacebar | 29 (F0 29) |
| 5 | 2E (F0 2E) | Alt (right) | E0 11 (E0 F0 11) |
| 6 | 36 (F0 36) | Windows (right) | E0 27 (E0 F0 27) |
| 7 | 3D (F0 3D) | Menus | E0 2F (E0 F0 2F) |
| 8 | 3E (F0 3E) | Ctrl (right) | E0 14 (E0 F0 14) |
| 9 | 46 (F0 46) | Insert | E0 70 (E0 F0 70) |
| 0 | 45 (F0 45) | Home | E0 6C (E0 F0 6C) |
| - | 4E (F0 4E) | Page Up | E0 7D (E0 F0 7D) |
| = | 55 (F0 55) | Delete | E0 71 (E0 F0 71) |
| Backspace | 66 (F0 66) | End | E0 69 (E0 F0 69) |
| Tab | 0D (F0 0D) | Page Down | E0 7A (E0 F0 7A) |
| Q | 15 (F0 15) | Up Arrow | E0 75 (E0 F0 75) |
| W | 1D (F0 1D) | Left Arrow | E0 6B (E0 F0 6B) |
| E | 24 (F0 24) | Down Arrow | E0 72 (E0 F0 72) |
| R | 2D (F0 2D) | Right Arrow | E0 74 (E0 F0 74) |
| T | 2C (F0 2C) | Num Lock | 77 (F0 77) |
| Y | 35 (F0 35) | / (keypad) | E0 4A (E0 F0 4A) |
| U | 3C (F0 3C) | * (keypad) | 7C (F0 7C) |
| I | 43 (F0 43) | - (keypad) | 7B (F0 7B) |
| O | 44 (F0 44) | 7 (keypad) | 6C (F0 6C) |
| P | 4D (F0 4D) | 8 (keypad) | 75 (F0 75) |
| [ | 54 (F0 54) | 9 (keypad) | 7D (F0 7D) |
| ] | 5B (F0 5B) | + (keypad) | 79 (F0 79) |
| \ | 5D (F0 5D) | 4 (keypad) | 6B (F0 6B) |
| Caps Lock | 58 (F0 58) | 5 (keypad) | 73 (F0 73) |
| A | 1C (F0 1C) | 6 (keypad) | 74 (F0 74) |
| S | 1B (F0 1B) | 1 (keypad) | 69 (F0 69) |
| D | 23 (F0 23) | 2 (keypad) | 72 (F0 72) |
| F | 2B (F0 2B) | 3 (keypad) | 7A (F0 7A) |
| G | 34 (F0 34) | 0 (keypad) | 70 (F0 70) |
| H | 33 (F0 33) | . (keypad) | 71 (F0 71) |
| J | 3B (F0 3B) | Enter (keypad) | E0 5A (E0 F0 5A) |
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