history: document ANSI escape sequences used

[pforth] / fth / termio.fth

\ Terminal I/O
\
\ Requires an ANSI compatible terminal.
\
\ To get Windows computers to use ANSI mode in their DOS windows,
\ Add this line to "C:\CONFIG.SYS" then reboot.
\
\  device=c:\windows\command\ansi.sys
\
\ Author: Phil Burk
\ Copyright 1988 Phil Burk
\ Revised 2001 for pForth

ANEW TASK-TERMIO.FTH
decimal

$ 08 constant ASCII_BACKSPACE
$ 7F constant ASCII_DELETE
$ 1B constant ASCII_ESCAPE
$ 01 constant ASCII_CTRL_A
$ 05 constant ASCII_CTRL_E
$ 18 constant ASCII_CTRL_X

\ ANSI arrow key sequences
\ ESC [ 0x41 is UP
\ ESC [ 0x42 is DOWN
\ ESC [ 0x43 is RIGHT
\ ESC [ 0x44 is LEFT

\ ANSI terminal control
\ ESC [ 2J is clear screen
\ ESC [ {n} D is move left
\ ESC [ {n} C is move right
\ ESC [ K is erase to end of line

: ESC[ ( send ESCAPE and [ )
    ASCII_ESCAPE emit
    ascii [ emit
;

: CLS ( -- , clear screen )
    ESC[ ." 2J"
;

: TIO.BACKWARDS ( n -- , move cursor backwards )
    ESC[
    base @ >r decimal
    0 .r
    r> base !
    ascii D emit
;

: TIO.FORWARDS ( n -- , move cursor forwards )
    ESC[
    base @ >r decimal
    0 .r
    r> base !
    ascii C emit
;

: TIO.ERASE.EOL ( -- , erase to the end of the line )
    ESC[
    ascii K emit
;

: BELL ( -- , ring the terminal bell )
    7 emit
;

: BACKSPACE ( -- , backspace action )
    8 emit  space  8 emit
;

0 [IF] \ for testing

: SHOWKEYS  ( -- , show keys pressed in hex )
    BEGIN
        key
        dup .
        ." , $ " dup .hex cr
        ascii q =
    UNTIL
;

: AZ ascii z 1+ ascii a DO i emit LOOP ;

: TEST.BACK1
    AZ 5 tio.backwards
    1000 msec
    tio.erase.eol
;
: TEST.BACK2
    AZ 10 tio.backwards
    1000 msec
    ." 12345"
    1000 msec
;
[THEN]