The Keypressed option in formula uses the virtual key codes.

Here is the example for enter key on keyboard:


Symbolic constant nameValue
(decimal)		Mouse or keyboard equivalent
VK_LBUTTON1Left mouse button
VK_RBUTTON2Right mouse button
VK_CANCEL3Control-break processing
VK_MBUTTON4Middle mouse button (three-button mouse)
VK_XBUTTON15Windows 2000: X1 mouse button
VK_XBUTTON26Windows 2000: X2 mouse button
—7Undefined
VK_BACK8BACKSPACE key
VK_TAB9TAB key
—10–11Reserved
VK_CLEAR12CLEAR key
VK_RETURN13ENTER key
—14–15Undefined
VK_SHIFT16SHIFT key
VK_CONTROL17CTRL key
VK_MENU18ALT key
VK_PAUSE19PAUSE key
VK_CAPITAL20CAPS LOCK key
VK_KANA21IME Kana mode
VK_HANGUEL21IME Hanguel mode (maintained for compatibility; use VK_HANGUL)
VK_HANGUL21IME Hangul mode
—22Undefined
VK_JUNJA23IME Junja mode
VK_FINAL24IME final mode
VK_HANJA25IME Hanja mode
VK_KANJI25IME Kanji mode
—26Undefined
VK_ESCAPE27ESC key
VK_CONVERT28IME convert
VK_NONCONVERT29IME nonconvert
VK_ACCEPT30IME accept
VK_MODECHANGE31IME mode change request
VK_SPACE32SPACEBAR
VK_PRIOR33PAGE UP key
VK_NEXT34PAGE DOWN key
VK_END35END key
VK_HOME36HOME key
VK_LEFT37LEFT ARROW key
VK_UP38UP ARROW key
VK_RIGHT39RIGHT ARROW key
VK_DOWN40DOWN ARROW key
VK_SELECT41SELECT key
VK_PRINT42PRINT key
VK_EXECUTE43EXECUTE key
VK_SNAPSHOT44PRINT SCREEN key
VK_INSERT45INS key
VK_DELETE46DEL key
VK_HELP47HELP key
 480 key
 491 key
 502 key
 513 key
 524 key
 535 key
 546 key
 557 key
 568 key
 579 key
—58–64Undefined
 65A key
 66B key
 67C key
 68D key
 69E key
 70F key
 71G key
 72H key
 73I key
 74J key
 75K key
 76L key
 77M key
 78N key
 79O key
 80P key
 81Q key
 82R key
 83S key
 84T key
 85U key
 86V key
 87W key
 88X key
 89Y key
 90Z key
VK_LWIN91Left Windows key (Microsoft® Natural® keyboard)
VK_RWIN92Right Windows key (Natural keyboard)
VK_APPS93Applications key (Natural keyboard)
—94Reserved
VK_SLEEP95Computer Sleep key
VK_NUMPAD096Numeric keypad 0 key
VK_NUMPAD197Numeric keypad 1 key
VK_NUMPAD298Numeric keypad 2 key
VK_NUMPAD399Numeric keypad 3 key
VK_NUMPAD4100Numeric keypad 4 key
VK_NUMPAD5101Numeric keypad 5 key
VK_NUMPAD6102Numeric keypad 6 key
VK_NUMPAD7103Numeric keypad 7 key
VK_NUMPAD8104Numeric keypad 8 key
VK_NUMPAD9105Numeric keypad 9 key
VK_MULTIPLY106Multiply key
VK_ADD107Add key
VK_SEPARATOR108Separator key
VK_SUBTRACT109Subtract key
VK_DECIMAL110Decimal key
VK_DIVIDE111Divide key
VK_F1112F1 key
VK_F2113F2 key
VK_F3114F3 key
VK_F4115F4 key
VK_F5116F5 key
VK_F6117F6 key
VK_F7118F7 key
VK_F8119F8 key
VK_F9120F9 key
VK_F10121F10 key
VK_F11122F11 key
VK_F12123F12 key
VK_F13124F13 key
VK_F14125F14 key
VK_F15126F15 key
VK_F16127F16 key
VK_F17128HF17 key
VK_F18129HF18 key
VK_F19130HF19 key
VK_F20131HF20 key
VK_F21132HF21 key
VK_F22133HF22 key
VK_F23134HF23 key
VK_F24135HF24 key
—136–143Unassigned
VK_NUMLOCK144NUM LOCK key
VK_SCROLL145SCROLL LOCK key
 146–150OEM specific
—151–159Unassigned
VK_LSHIFT160Left SHIFT key
VK_RSHIFT161Right SHIFT key
VK_LCONTROL162Left CONTROL key
VK_RCONTROL163Right CONTROL key
VK_LMENU164Left MENU key
VK_RMENU165Right MENU key
VK_BROWSER_BACK166Windows 2000: Browser Back key
VK_BROWSER_FORWARD167Windows 2000: Browser Forward key
VK_BROWSER_REFRESH168Windows 2000: Browser Refresh key
VK_BROWSER_STOP169Windows 2000: Browser Stop key
VK_BROWSER_SEARCH170Windows 2000: Browser Search key
VK_BROWSER_FAVORITES171Windows 2000: Browser Favorites key
VK_BROWSER_HOME172Windows 2000: Browser Start and Home key
VK_VOLUME_MUTE173Windows 2000: Volume Mute key
VK_VOLUME_DOWN174Windows 2000: Volume Down key
VK_VOLUME_UP175Windows 2000: Volume Up key
VK_MEDIA_NEXT_TRACK176Windows 2000: Next Track key
VK_MEDIA_PREV_TRACK177Windows 2000: Previous Track key
VK_MEDIA_STOP178Windows 2000: Stop Media key
VK_MEDIA_PLAY_PAUSE179Windows 2000: Play/Pause Media key
VK_LAUNCH_MAIL180Windows 2000: Start Mail key
VK_LAUNCH_MEDIA_SELECT181Windows 2000: Select Media key
VK_LAUNCH_APP1182Windows 2000: Start Application 1 key
VK_LAUNCH_APP2183Windows 2000: Start Application 2 key
—184-185Reserved
VK_OEM_1186Windows 2000: For the US standard keyboard, the ';:' key
VK_OEM_PLUS187Windows 2000: For any country/region, the '+' key
VK_OEM_COMMA188Windows 2000: For any country/region, the ',' key
VK_OEM_MINUS189Windows 2000: For any country/region, the '-' key
VK_OEM_PERIOD190Windows 2000: For any country/region, the '.' key
VK_OEM_2191Windows 2000: For the US standard keyboard, the '/?' key
VK_OEM_3192Windows 2000: For the US standard keyboard, the '`~' key
—193–215Reserved
—216–218Unassigned
VK_OEM_4219Windows 2000: For the US standard keyboard, the '[{' key
VK_OEM_5220Windows 2000: For the US standard keyboard, the '\|' key
VK_OEM_6221Windows 2000: For the US standard keyboard, the ']}' key
VK_OEM_7222Windows 2000: For the US standard keyboard, the 'single-quote/double-quote' key
VK_OEM_8223
—224Reserved
 225OEM specific
VK_OEM_102226Windows 2000: Either the angle bracket key or the backslash key on the RT 102-key keyboard
 227–228OEM specific
VK_PROCESSKEY229Windows 95/98, Windows NT 4.0, Windows 2000: IME PROCESS key
 230OEM specific
VK_PACKET231Windows 2000: Used to pass Unicode characters as if they were keystrokes. The VK_PACKET key is the low word of a 32-bit Virtual Key value used for non-keyboard input methods. For more information, see Remark in KEYBDINPUT, SendInput, WM_KEYDOWN, and WM_KEYUP
—232Unassigned
 233–245OEM specific
VK_ATTN246Attn key
VK_CRSEL247CrSel key
VK_EXSEL248ExSel key
VK_EREOF249Erase EOF key
VK_PLAY250Play key
VK_ZOOM251Zoom key
VK_NONAME252Reserved for future use
VK_PA1253PA1 key
VK_OEM_CLEAR254Clear key