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ASCII and Extended Codes
ASCII Control 0 to 31 | ASCII Keyboard Character Codes 32 to 127 | |||||||
---|---|---|---|---|---|---|---|
Code | Character [key] | Code | Character | Code | Character | Code | Character |
0 | (NUL) | 32 | [Spacebar] | 64 | @ | 96 | ` |
1 | ? (SOH) | 33 | ! | 65 | A | 97 | a |
2 | ? (STX) | 34 | " | 66 | B | 98 | b |
3 | ? (ETX) | 35 | # | 67 | C | 99 | c |
4 | ? (EOT) | 36 | $ | 68 | D | 100 | d |
5 | ? (ENQ) | 37 | % | 69 | E | 101 | e |
6 | ? (ACK) | 38 | & | 70 | F | 102 | f |
7 | • (BEL) BEEP | 39 | ' | 71 | G | 103 | g |
8 | ? [BackSpace] ** | 40 | ( | 72 | H | 104 | h |
9 | ? (HT) [TAB] ** | 41 | ) | 73 | I | 105 | i |
10 | ? (LineFeed) ** | 42 | * | 74 | J | 106 | j |
11 | ? (VT) ** | 43 | + | 75 | K | 107 | k |
12 | ? (FormFeed) ** | 44 | , | 76 | L | 108 | l |
13 | ? (CR) [Enter] ** | 45 | - | 77 | M | 109 | m |
14 | ? (SO) | 46 | . | 78 | N | 110 | n |
15 | ¤ (SI) | 47 | / | 79 | O | 111 | o |
16 | ? (DLE) | 48 | 0 | 80 | P | 112 | p |
17 | ? (DC1) | 49 | 1 | 81 | Q | 113 | q |
18 | ? (DC2) | 50 | 2 | 82 | R | 114 | r |
19 | ? (DC3) | 51 | 3 | 83 | S | 115 | s |
20 | ¶ (DC4) | 52 | 4 | 84 | T | 116 | t |
21 | § (NAK) | 53 | 5 | 85 | U | 117 | u |
22 | ? (SYN) | 54 | 6 | 86 | V | 118 | v |
23 | ? (ETB) | 55 | 7 | 87 | W | 119 | w |
24 | ? (CAN) | 56 | 8 | 88 | X | 120 | x |
25 | ? (EM) | 57 | 9 | 89 | Y | 121 | y |
26 | ? (SUB) EOF | 58 | : | 90 | Z | 122 | z |
27 | ? (ESC) [Esc] | 59 | ; | 91 | [ | 123 | { |
28 | ? (FS) ** | 60 | < | 92 | \ | 124 | | |
29 | ? (GS) ** | 61 | = | 93 | ] | 125 | } |
30 | ? (RS) ** | 62 | > | 94 | ^ | 126 | ~ |
31 | ? (US) ** | 63 | ? | 95 | _ | 127 | ¦ (DEL) * |
IBM, International, graphical, mathematical and other characters | |||||||
Code | Character | Code | Character | Code | Character | Code | Character |
128 | Ç | 160 | á | 192 | + | 224 | a |
129 | ü | 161 | í | 193 | - | 225 | ß |
130 | é | 162 | ó | 194 | - | 226 | G |
131 | â | 163 | ú | 195 | + | 227 | p |
132 | ä | 164 | ñ | 196 | - | 228 | S |
133 | à | 165 | Ñ | 197 | + | 229 | s |
134 | å | 166 | ª | 198 | ¦ | 230 | µ |
135 | ç | 167 | º | 199 | ¦ | 231 | t |
136 | ê | 168 | ¿ | 200 | + | 232 | F |
137 | ë | 169 | ¬ | 201 | + | 233 | T |
138 | è | 170 | ¬ | 202 | - | 234 | O |
139 | ï | 171 | ½ | 203 | - | 235 | d |
140 | î | 172 | ¼ | 204 | ¦ | 236 | 8 |
141 | ì | 173 | ¡ | 205 | - | 237 | f |
142 | Ä | 174 | « | 206 | + | 238 | e |
143 | Å | 175 | » | 207 | - | 239 | n |
144 | É | 176 | ¦ | 208 | - | 240 | = |
145 | æ | 177 | ¦ | 209 | - | 241 | ± |
146 | Æ | 178 | ¦ | 210 | - | 242 | = |
147 | ô | 179 | ¦ | 211 | + | 243 | = |
148 | ö | 180 | ¦ | 212 | + | 244 | ( |
149 | ò | 181 | ¦ | 213 | + | 245 | ) |
150 | û | 182 | ¦ | 214 | + | 246 | ÷ |
151 | ù | 183 | + | 215 | + | 247 | ˜ |
152 | ÿ | 184 | + | 216 | + | 248 | ° |
153 | Ö | 185 | ¦ | 217 | + | 249 | · |
154 | Ü | 186 | ¦ | 218 | + | 250 | · |
155 | ¢ | 187 | + | 219 | ¦ | 251 | v |
156 | £ | 188 | + | 220 | _ | 252 | n |
157 | ¥ | 189 | + | 221 | ¦ | 253 | ² |
158 | P | 190 | + | 222 | ¦ | 254 | ¦ |
159 | ƒ | 191 | + | 223 | ¯ | 255 | NBSP *** |
- * DEL was used to erase paper tape data by punching out all of the 7 holes.
- ** Control characters 8 to 13 and 28 to 31 can move text formatting when printed and do not display
- *** NBSP is a Non-breaking Space used to indent text. Some browsers may handle this character differently
Control Characters
- INKEY$ will return Control + letter key press combinations as the equivalent control characters or bold function keys listed below:
Template:WhiteStart CTRL + A = CHR$(1) ? StartHeader (SOH) CTRL + B = CHR$(2) ? StartText (STX)
CTRL + C = CHR$(3) ? EndText (ETX) CTRL + D = CHR$(4) ? EndOfTransmit (EOT) CTRL + E = CHR$(5) ? Enquiry (ENQ) CTRL + F = CHR$(6) ? Acknowledge (ACK) CTRL + G = CHR$(7) • Bell (BEL) CTRL + H = CHR$(8) ? [Backspace] (BSP) CTRL + I = CHR$(9) ? Horiz.Tab [Tab] CTRL + J = CHR$(10) ? LineFeed(printer) (LF) CTRL + K = CHR$(11) ? Vert. Tab (VT) CTRL + L = CHR$(12) ? FormFeed(printer) (FF) CTRL + M = CHR$(13) ? [Enter] (CR) CTRL + N = CHR$(14) ? ShiftOut (SO) CTRL + O = CHR$(15) ¤ ShiftIn (SI) CTRL + P = CHR$(16) ? DataLinkEscape (DLE) CTRL + Q = CHR$(17) ? DevControl1 (DC1) CTRL + R = CHR$(18) ? DeviceControl2 (DC2) CTRL + S = CHR$(19) ? DevControl3 (DC3) CTRL + T = CHR$(20) ¶ DeviceControl4 (DC4) CTRL + U = CHR$(21) § NegativeACK (NAK) CTRL + V = CHR$(22) ? Synchronous Idle (SYN) CTRL + W = CHR$(23) ? EndTXBlock (ETB) CTRL + X = CHR$(24) ? Cancel (CAN) CTRL + Y = CHR$(25) ? EndMedium (EM) CTRL + Z = CHR$(26) ? End Of File(SUB) (EOF)
Red symbols will format text and not PRINT the symbol. _PRINTSTRING can print in QB64
- Control characters 1 to 26 can be used to simulate Ctrl + letter key shortcuts in Windows programs using _SCREENPRINT.
- _CONTROLCHR OFF can also be used in QB64 to allow control characters to be printed without formatting the text.
- Characters 0(NULL) and 255(NBSP) can also be used to print spaces(32). Useful for making file names harder to delete too.
- Character 7 will create a BEEP sound when printed in QB64 or an error sound in QBasic using a SCREEN 0 window.
- Character 8 is returned when the Backspace key is pressed.
- Characters 9 thru 13 and 28 thru 31 can affect screen or file text placements and do not display the character when printed:
- Character 9 will Tab space the cursor 8 column spaces when printed.
- Character 10 moves the cursor or "line feeds" the printer head down one row.
- Character 11 vertical tabs the cursor back to top left position of page or screen. Acts like CLS.
- Character 12 acts like CLS when printed. "Form feeds" the page out of printers.
- Character 13 is the cursor or typing "carriage return" to the start of the line on left side. Returned when Enter key pressed.
- Character 28 designates a File Separator. Moves the print cursor one space right. Combination Ctrl + \
- Character 29 designates a Group Separator. Moves the print cursor one space left. Combination Ctrl + ]
- Character 30 designates a Record Separator. Moves the print cursor one row up. Combination Ctrl + ^
- Character 31 designates a Unit Separator. Moves the print cursor one row down. Combination Ctrl + _
- QB64 can display all of the control characters without formatting the text using _PRINTSTRING.
- Characters 13 and 10 can be combined to create the CrLf carriage return used in files or printing. crlf$ = CHR$(13) + CHR$(10).
- Character 16, the data link escape(DLE) character, can designate that a control character is being sent from a COM port.
- Example: (DLE) <XON> (DLE) <XOFF> or (DLE) <STX> (DLE) <ETX>
- Character 17, Device Control 1, is used with COM ports to mark the start of a transmission as "XON". The character is read.
- Character 19, Device Control 3, is used with COM ports to mark the end of a transmission as "XOFF". The character is NOT read.
- Character 26 can be used to designate the end of a file. See EOF.
- Character 27 ? is returned when the Escape key is pressed.
SCREEN 12 COLOR 14: PRINT "Press Control + letter key combinations." DO K$ = INKEY$ IF LEN(K$) THEN code = ASC(K$) IF code < 32 THEN _PRINTSTRING (220, 100), "Ctrl + " + CHR$(code + 64) + " = " + K$ + " " END IF LOOP UNTIL K$ = CHR$(27) END |
- Characters are one byte and take up one space(byte) in a STRING value or variable.
- Extended(non-keyboard) characters can be entered by holding down Alt key and entering the code number on the Number pad.
- PRINTs text characters and symbols or formats the screen, printer or file.
- BINARY files often store values below 256 in the one byte character. To read the value get the code with ASC.
- Numerical values placed into a BINARY or RANDOM file using a GET or PUT variable, they will be stored in _MK$ format.
- Characters 176 to 223 can be used to create screen borders or boundaries in an ASCII game. See: SCREEN (function)
- Character 253(small 2) can be found as the first character byte of a BSAVEd image file opened in BINARY mode.
- Character 255 can be used as the NBSP(non-breaking space) character on web pages to fill in extra spaces.
- Can be used to crudely encrypt a file so others cannot read it by shifting the code values. See CHR$ example 2.
ASC Codes
Template:WhiteStart' ASCII Keyboard Codes ' ' Esc F1 F2 F3 F4 F5 F6 F7 F8 F9 F10 F11 F12 Sys ScL Pause ' 27 +59 +60 +61 +62 +63 +64 +65 +66 +67 +68 +133 +134 - - - ' `~ 1! 2@ 3# 4$ 5% 6^ 7& 8* 9( 0) -_ =+ BkSp Ins Hme PUp NumL / * - ' 126 33 64 35 36 37 94 38 42 40 41 95 43 8 +82 +71 +73 - 47 42 45 ' 96 49 50 51 52 53 54 55 56 57 48 45 61 ' Tab Q W E R T Y U I O P [{ ]} \| Del End PDn 7Hme 8/? 9PU + ' 9 81 87 69 82 84 89 85 73 79 80 123 125 124 +83 +79 +81 +71 +72 +73 43 ' 113 119 101 114 116 121 117 105 111 112 91 93 92 55 56 57 ' CapL A S D F G H J K L ;: '" Enter 4/?- 5 6/-? ' - 65 83 68 70 71 72 74 75 76 58 34 13 +75 +76 +77 E ' 97 115 100 102 103 104 106 107 108 59 39 52 53 54 n ' Shift Z X C V B N M ,< .> /? Shift ? 1End 2/? 3PD t ' * 90 88 67 86 66 78 77 60 62 63 * +72 +79 +80 +81 e ' 122 120 99 118 98 110 109 44 46 47 49 50 51 r ' Ctrl Win Alt Spacebar Alt Win Menu Ctrl ?- ? -? 0Ins .Del ' * - * 32 * - - * +75 +80 +77 +82 +83 13 ' 48 46 ' ' Italics = LCase/NumLock On ____________ + = 2 Byte: CHR$(0) + CHR$(code)
'
' Demo displays all ASCII codes and 2 byte code combinations DO: K$ = INKEY$ IF K$ <> "" THEN 'ASC will return an error if an empty string is read! IF ASC(K$) > 0 THEN PRINT "CHR$(" + LTRIM$(STR$(ASC(K$))) + ")" 'display normal keypress codes ELSE PRINT "CHR$(0) + CHR$(" + LTRIM$(STR$(ASC(K$, 2))) + ")" 'display 2 byte codes END IF END IF LOOP UNTIL K$ = CHR$(27) 'escape key press exits |
- Note: In QB64 ASC(K$, 2) can read the second byte of the 2 byte code when ASC(K$) reads the first byte as 0.
Two Byte Codes
- INKEY$ returns both bytes when two byte keys or key combinations are pressed. The second byte = RIGHT$(keypress$, 1)
- If the character returned is a two byte code, ASC will return 0. Warning: ASC cannot read empty INKEY$ string values!
- In QB64 only, ASC(keypress$, 2) can return the second byte code. Don't read empty string values!
- String values returned can be compared in an IF or SELECT CASE routine by using the actual string definitions such as:
- IF INKEY$ = CHR$(0) + CHR$(80) THEN row = row + 1 or IF INKEY$ = CHR$(0) + "P" THEN row = row + 1
Template:WhiteStart Two Byte Character Codes Key CHR$(0) + "?"
CHR$(0) + CHR$(16-50) [Alt] + letter CHR$(0) + CHR$(59) [F1] ";" CHR$(0) + CHR$(60) [F2] "<" CHR$(0) + CHR$(61) [F3] "=" CHR$(0) + CHR$(62) [F4] ">" CHR$(0) + CHR$(63) [F5] "?" CHR$(0) + CHR$(64) [F6] "@" CHR$(0) + CHR$(65) [F7] "A" CHR$(0) + CHR$(66) [F8] "B" CHR$(0) + CHR$(67) [F9] "C" CHR$(0) + CHR$(68) [F10] "D" CHR$(0) + CHR$(71) [Home] "G" CHR$(0) + CHR$(72) [?] Up Arrow "H" CHR$(0) + CHR$(73) [Page Up] "I" CHR$(0) + CHR$(75) [?] Left Arrow "K" CHR$(0) + CHR$(76) [5 NumberPad] "L" (NumLock off in QB64) CHR$(0) + CHR$(77) [?] Right Arrow "M" CHR$(0) + CHR$(79) [End] "O" CHR$(0) + CHR$(80) [?] Down Arrow "P" CHR$(0) + CHR$(81) [Page Down] "Q" CHR$(0) + CHR$(82) [Insert] "R" CHR$(0) + CHR$(83) [Delete] "S" CHR$(0) + CHR$(84-93) [Shift] + F1-10 CHR$(0) + CHR$(94-103) [Ctrl] + F1-10 CHR$(0) + CHR$(104-113) [Alt] + F1-10 CHR$(0) + CHR$(114-119) [Ctrl] + keypad CHR$(0) + CHR$(120-129) [Alt] + number CHR$(0) + CHR$(130 or 131) [Alt] + _/- or +/= "é" or "â" CHR$(0) + CHR$(133) [F11] "à" CHR$(0) + CHR$(134) [F12] "å" CHR$(0) + CHR$(135) [Shift] + [F11] "ç" CHR$(0) + CHR$(136) [Shift] + [F12] "ê" CHR$(0) + CHR$(137) [Ctrl] + [F11] "ë" CHR$(0) + CHR$(138) [Ctrl] + [F12] "è" CHR$(0) + CHR$(139) [Alt] + [F11] "ï" CHR$(0) + CHR$(140) [Alt] + [F12] "î"
- In QB64, CVI can be used to get the _KEYDOWN 2-byte code value. Example: status = _KEYDOWN(CVI(CHR$(0) + "P"))
Code Examples
Example 1: Using arrow keys to move a text character. A change from a previous position tells program when to PRINT:
movey = 1: movex = 1 'text coordinates can never be 0 at$ = "@" 'text sprite could be almost any ASCII character LOCATE movey, movex: PRINT at$; DO px = movex: py = movey 'previous positions B$ = INKEY$ IF B$ = CHR$(0) + CHR$(72) AND movey > 1 THEN movey = movey - 1 'rows 1 to 23 only IF B$ = CHR$(0) + CHR$(80) AND movey < 23 THEN movey = movey + 1 IF B$ = CHR$(0) + CHR$(75) AND movex > 1 THEN movex = movex - 1 'columns 1 to 80 only IF B$ = CHR$(0) + CHR$(77) AND movex < 80 THEN movex = movex + 1 IF px <> movex OR py <> movey THEN 'only changes when needed LOCATE py, px: PRINT SPACE$(1); 'erase old sprite LOCATE movey, movex: PRINT at$; 'show new position END IF LOOP UNTIL B$ = CHR$(27) 'ESCape key exit END |
Example 2: Routine displays all keypress codes including Ctrl, Alt and Shift combinations. Ctrl + letter = control codes 1 to 26.
SCREEN 13 tmp$ = " CHR$(###),\\,\ \ " tmp2$ = " CHR$(0) + CHR$(###) \ \" COLOR 14: LOCATE 3, 3: PRINT "The code can tell what key is pressed" COLOR 12: LOCATE 5, 14: PRINT CHR$(3); SPACE$(3); COLOR 13: PRINT CHR$(5); SPACE$(3); COLOR 12: PRINT CHR$(4); SPACE$(3); COLOR 13: PRINT CHR$(6) COLOR 10: LOCATE 7, 4: PRINT " Hit a key to find the ASCII Code" COLOR 5: LOCATE 13, 1: PRINT " Codes below 33 are called control keys" LOCATE 14, 1: PRINT " CHR$(0) + are 2 byte Extended key codes" COLOR 13: LOCATE 16, 1: PRINT " Extended: Press Alt + numberpad: Enter" LOCATE 18, 1: PRINT " Try some Ctrl, Alt, or Shift Combo's" COLOR 5: LOCATE 20, 1: PRINT " INKEY$ is used to detect the key entry" COLOR 2: LOCATE 22, 15: PRINT CHR$(1); " "; CHR$(2) COLOR 4: LOCATE 24, 10: PRINT "To Quit hit the TAB key"; COLOR 9 DO DO: SLEEP: A$ = INKEY$: LOOP UNTIL A$ <> "" 'legal ASC read keys IF ASC(A$) > 0 THEN ' normal key codes code% = ASC(A$) SELECT CASE code% CASE 7: Key$ = "Beep" CASE 8: Key$ = "Backspace" CASE 9: Key$ = "Tab Key" CASE 10: Key$ = "Line Feed" CASE 12: Key$ = "Form Feed" CASE 13: Key$ = "Enter" CASE 27: Key$ = "Escape" CASE 32: Key$ = "Space Bar" CASE 48 TO 57: Key$ = "Number" CASE 65 TO 90: Key$ = "Uppercase" CASE 97 TO 122: Key$ = "Lowercase" CASE ELSE: Key$ = "" END SELECT SELECT CASE code% 'check for unprintable control combo characters CASE 10 TO 13: Kcode% = 32 CASE ELSE: Kcode% = code% END SELECT COLOR 9: LOCATE 10, 5: PRINT USING tmp$; code%; CHR$(Kcode%); Key$; END IF IF ASC(A$) = 0 THEN 'two byte key codes code% = ASC(RIGHT$(A$, 1)) 'QBasic code 'code% = ASC(A$, 2) 'QB64 code alternative SELECT CASE code% CASE 16 TO 50: Key$ = "Alt+ letter" CASE 72: Key$ = CHR$(24) + " Arrow" CASE 75: Key$ = CHR$(27) + " Arrow" CASE 77: Key$ = CHR$(26) + " Arrow" CASE 80: Key$ = CHR$(25) + " Arrow" CASE 83: Key$ = "Delete" CASE 59: Key$ = "F1" CASE 60: Key$ = "F2" CASE 61: Key$ = "F3" CASE 62: Key$ = "F4" CASE 63: Key$ = "F5" CASE 64: Key$ = "F6" CASE 65: Key$ = "F7" CASE 66: Key$ = "F8" CASE 67: Key$ = "F9" CASE 68: Key$ = "F10" CASE 71: Key$ = "Home" CASE 73: Key$ = "Page " + CHR$(24) CASE 79: Key$ = "End" CASE 81: Key$ = "Page " + CHR$(25) CASE 82: Key$ = "Insert" CASE 83: Key$ = "Delete" CASE 84 TO 93: Key$ = "Shift+ F" CASE 94 TO 103: Key$ = "Ctrl+ F" CASE 104 TO 113: Key$ = "Alt+ F" CASE 114 TO 119: Key$ = "Ctrl + pad" CASE 120 TO 129: Key$ = "Alt+ number" CASE 132: Key$ = "Ctrl + pad" CASE 133: Key$ = "F11" CASE 134: Key$ = "F12" CASE 135: Key$ = "Shift+ F11" CASE 136: Key$ = "Shift+ F12" CASE 137: Key$ = "Ctrl+ F11" CASE 138: Key$ = "Ctrl+ F12" CASE 139: Key$ = "Alt+ F11" CASE 140: Key$ = "Alt+ F12" CASE ELSE: Key$ = "" END SELECT LOCATE 10, 5: PRINT USING tmp2$; code%; Key$ END IF LOOP UNTIL A$ = CHR$(9) SOUND 400, 4 SLEEP 3 SYSTEM |
Explanation: The routine checks for a keypress and SLEEP guarantees that ASC will never read an empty string from INKEY$. When the keypress is determined to be two bytes (ASC(A$) = 0) the second SELECT CASE routine is used. You can even display non-keyboard extended characters. Just press Alt + numberpad code, release and press enter.
- Note: Ctrl + letter keys will list the contol keys as normal codes. EX: Ctrl + G will BEEP (CHR$(7)).
References
Printable ASCII Table: _PRINTIMAGE (see Example 2 on page)
See also
- _KEYHIT, _KEYDOWN
- _MAPUNICODE, _MAPUNICODE (function)
- Code Pages (Various Unicode Languages)
- ASC (statement) (QB64 only)
- ASC, INSTR
- CHR$, INKEY$
- LEFT$, MID$, RIGHT$
- PRINT, SCREEN
- MKI$, MKL$, MKS$, MKD$, _MK$
- _PRINTSTRING, _SCREENPRINT
- _CONTROLCHR (turns control PRINT actions OFF/ON)
- Scancodes(keyboard), Unicode(character table)
- Text Using Graphics