NANSI.SYS source
David P. Zimmerman
dpz at topaz.RUTGERS.EDU
Sun May 11 11:44:40 AEST 1986
---- file nansi.cat ----
See nansi.doc for information
# Makefile for nansi.sys- name it 'nansi' and delete hashed lines
# Requires the Microsoft Macro Assembler version 3 or higher.
nansi.obj: nansi.asm nansi_d.asm
masm nansi,,nansi;
nansi_p.obj: nansi_p.asm
masm nansi_p,,nansi_p;
nansi_f.obj: nansi_f.asm nansi_d.asm
masm nansi_f,,nansi_f;
nansi_i.obj: nansi_i.asm nansi_d.asm
masm nansi_i,,nansi_i;
nansi.sys: nansi.obj nansi_p.obj nansi_f.obj nansi_i.obj
link /map nansi nansi_p nansi_f nansi_i;
exe2bin nansi nansi.sys
rm nansi.exe
# end of makefile for nansi.sys
;---- nansi_d.asm -----------------
; Definitions for the new ANSI driver.
; (C) 1986 Daniel Kegel
; May be distributed for educational and personal use only
takeBIOS equ 0 ; take over BIOS write_tty if true
is_8088 equ 1 ; no fancy instructions if true
cls_homes_too equ 1 ; set true for ANSI.SYS compatibility
;Comment this out if running MASM 1.0
if is_8088
.8086
else
.286c
endif
;---- end of nansi_d.asm ----
page 66, 132
;--- nansi.asm ----------------------------------------------------------
; New ANSI terminal driver.
; Optimized for speed in the case of multi-character write requests.
; (C) 1986 Daniel Kegel, Pasadena, CA
; May be distributed for educational and personal use only
; The following files make up the driver:
; nansi.asm - all DOS function handlers except init
; nansi_p.asm - parameter parser for ANSI escape sequences
; nansi_f.asm - ANSI command handlers
; nansi_i.asm - init DOS function handler
;
; Daniel Kegel, Bellevue, Washington & Pasadena, California
; Revision history:
; 5 july 85: brought up non-ANSI portion except forgot backspace
; 6 july 85: split off ANSI stuff into other files, added backspace
; 11 july 85: fixed horrible bug in getchar; changed dosfns to subroutines
; 12 july 85: fixed some scrolling bugs, began adding compaq flag
; 9 aug 85: added cursor position reporting
; 10 aug 85: added output character translation
; 11 aug 85: added keyboard redefinition, some EGA 80x43 support
; 10 sept 85: Tandy 2000 support via compaq flag (finding refresh buffer)
; 30 Jan 86: removed Tandy 2000 stuff, added graphics mode support
; 12 feb 86: added int 29h handler, added PUSHA/POPA, added direct beep,
; direct cursor positioning, takeover of BIOS write_tty,
; noticed & squashed 2 related bugs in tab expansion
; 13 feb 86: Squashed them again, harder
; 24 feb 86: There is a bug in the timing code used by the BEEP routine.
; If the addition of the beep period to the
; BIOS low timer word results in an overflow, the beep will be
; supressed. Also made code compatible eith earlier versions
; of assembler.
;------------------------------------------------------------------------
include nansi_d.asm ; definitions
; from nansi_f.asm
extrn f_escape:near, f_in_escape:near
; from nansi_p.asm
extrn param_end:word, redef_end:word
; from nansi_i.asm
extrn dosfn0:near
; to nansi_p.asm
public f_loopdone
public f_not_ansi
public f_ansi_exit
; to both nansi_p.asm and nansi_f.asm
public cur_x, cur_y, max_x, cur_attrib
; to nansi_f.asm
public xy_to_regs, get_blank_attrib
public port_6845
public wrap_flag
public cur_parm_ptr
public cur_coords, saved_coords, max_y
public escvector, string_term
public cpr_esc, cprseq
public video_mode
public lookup
public in_g_mode
; to nansi_i.asm
public req_ptr, break_handler
public int_29
if takeBIOS
public new_vid_bios, old_vid_bios
endif
; to all modules
public xlate_tab_ptr
;--- seg_cs is the CS: override prefix
; (assembler forgets cs: on second "xlat dummy_cs_byte")
seg_cs macro
db 2eh
endm
;--- push_all, pop_all ------------------------------------------------
; Save/restore all user registers.
push_all macro
if is_8088
push ax
push bx
push cx
push dx
push bp
push si
push di
else
pusha
endif
endm
pop_all macro
if is_8088
pop di
pop si
pop bp
pop dx
pop cx
pop bx
pop ax
else
popa
endif
endm
keybuf struc ; Used in getchar
len dw ?
adr dw ?
keybuf ends
ABS40 segment at 40h
org 1ah
buffer_head dw ? ; Used in 'flush input buffer' dos call.
buffer_tail dw ?
org 49h
crt_mode db ?
crt_cols dw ?
crt_len dw ?
crt_start dw ?
cursor_posn dw 8 dup (?)
cursor_mode dw ?
active_page db ?
addr_6845 dw ?
crt_mode_set db ? ; = 7 only if monochrome display adaptor
crt_palette db ?
org 6ch
timer_low dw ? ; low word of time-of-day counter (18.2 hz)
ABS40 ends
page
CODE segment byte public 'CODE'
assume cs:code, ds:code
; Device Driver Header
org 0
dd -1 ; next device
dw 8013h ; attributes
dw strategy ; request header pointer entry
dw interrupt ; request entry point
db 'CON' ; device name (8 char)
db 5 dup (20h) ; ... and 5 blanks)
; Identification- in case somebody TYPEs the assembled driver
db 27,'[2J'
db "Nansi.sys v2.2"
ife is_8088
db "(80286)"
endif
db ': New ANSI driver (C) Daniel Kegel, Pasadena, CA 1986'
db 13, 10, 26
;----- variable area --------------------
req_ptr label dword
req_off dw ?
req_seg dw ?
wrap_flag db 1 ; 0 = no wrap past line end
escvector dw 0 ; state vector of ESCape sequencor
video_mode db 3 ; ROM BIOS video mode (2=BW, 3=color)
max_y db 24
max_cur_x label word ; used to get both max & cur at once
max_x db 79 ; line width (79 for 80x25 modes)
cur_coords label word
cur_x db 0 ; cursor position (0 = left edge)
cur_y db 0 ; (0 = top edge)
saved_coords dw ? ; holds XY after a SCP escape sequence
string_term db 0 ; either escape or double quote
cur_attrib db 7 ; current char attributes
cur_page db 0 ; current display page
video_seg dw ? ; segment of video card
f_cptr_seg dw ? ; part of fastout write buffer pointer
cur_parm_ptr dw ? ; last byte of parm area now used
port_6845 dw ? ; port address of 6845 card
xlate_tab_ptr dw ? ; pointer to output translation table
if takeBIOS
old_vid_bios dd ? ; pointer to old video bios routine
endif
brkkeybuf db 3 ; control C
fnkeybuf db ? ; holds second byte of fn key codes
cpr_buf db 8 dup (?), '['
cpr_esc db 1bh ; descending buffer for cpr function
; following four keybufs hold information about input
; Storage order determines priority- since the characters making up a function
; key code must never be separated (say, by a Control-Break), they have the
; highest priority, and so on. Keyboard keys (except ctrl-break) have the
; lowest priority.
fnkey keybuf <0, fnkeybuf> ; fn key string (0 followed by scan code)
cprseq keybuf <0> ; CPR string (ESC [ y;x R)
brkkey keybuf <0, brkkeybuf> ; ^C
xlatseq keybuf <0> ; keyboard reassignment string
;------ xy_to_regs --------------------------------------------
; on entry: x in cur_x, y in cur_y
; on exit: dx = chars left on line, di = address
; Alters ax, bx.
xy_to_regs proc near
; Find number of chars 'till end of line, keep in DX
mov ax, max_cur_x
mov bx, ax ; save max_x & cur_x for next block
mov ah, 0 ; ax = max_x
xchg dx, ax
mov al, bh
mov ah, 0 ; ax = cur_x
sub dx, ax
inc dx ; dx is # of chars till EOL
; Calculate DI = current address in text buffer
mov al, bl ; al = max_x
inc al
mul cur_y
add al, bh ; al += cur_x
adc ah, 0 ; AX is # of chars into buffer
add ax, ax
xchg di, ax ; DI is now offset of cursor.
ret
xy_to_regs endp
;------- dos_fn_tab -------------
; This table is used in "interrupt" to call the routine that handles
; the requested function.
max_cmd equ 12
dos_fn_tab:
dw dosfn0, nopcmd, nopcmd, badcmd, dosfn4, dosfn5, dosfn6
dw dosfn7, dosfn8, dosfn8, nopcmd, nopcmd
;------- strategy ----------------------------------------------------
; DOS calls strategy with a request which is to be executed later.
; Strategy just saves the request.
strategy proc far
mov cs:req_off,BX
mov cs:req_seg,ES
ret
strategy endp
;------ interrupt -----------------------------------------------------
; This is where the request handed us during "strategy" is
; actually carried out.
; Calls one of 12 subroutines depending on the function requested.
; Each subroutine returns with exit status in AX.
interrupt proc far
sti
push_all ; preserve caller's registers
push ds
push es
; Read requested function information into registers
lds bx,cs:req_ptr
mov al,[BX+02h] ; al = function code
;
; The next instruction blows up MASM 1.0 but who cares!!
;
les si,[BX+0Eh] ; ES:SI = input/output buffer addr
mov cx,[BX+12h] ; cx = input/output byte count
cmp al, max_cmd
ja unk_command ; too big, exit with error code
xchg bx, ax
shl bx, 1 ; form index to table of words
mov ax, cs
mov ds, ax
call word ptr dos_fn_tab[bx]
int_done:
lds bx,cs:req_ptr ; report status
or ax, 100h ; (always set done bit upon exit)
mov [bx+03],ax
pop ES ; restore caller's registers
pop DS
pop_all
ret ; return to DOS.
unk_command:
call badcmd
jmp int_done
interrupt endp
;----- BIOS break handler -----------------------------------------
; Called by BIOS when Control-Break is hit (vector was set up in Init).
; Simply notes that a break was hit. Flag is checked during input calls.
break_handler proc
mov cs:brkkey.len, 1
iret
break_handler endp
page
;------ badcmd -------------------------------------------------------
; Invalid function request by DOS.
badcmd proc near
mov ax, 813h ; return "Error: invalid cmd"
ret
badcmd endp
;------ nopcmd -------------------------------------------------------
; Unimplemented or dummy function request by DOS.
nopcmd proc near
xor ax, ax ; No error, not busy.
ret
nopcmd endp
;------- dos function #4 ----------------------------------------
; Reads CX characters from the keyboard, places them in buffer at
; ES:SI.
dosfn4 proc near
jcxz dos4done
mov di, si
dos4lp: push cx
call getchar
pop cx
stosb
loop dos4lp
dos4done:
xor ax, ax ; No error, not busy.
ret
dosfn4 endp
;-------- dos function #5: non-destructive input, no wait ------
; One-character lookahead into the keyboard buffer.
; If no characters in buffer, return BUSY; otherwise, get value of first
; character of buffer, stuff into request header, return DONE.
dosfn5 proc near
call peekchar
jz dos5_busy
lds bx,req_ptr
mov [bx+0Dh], al
xor ax, ax ; No error, not busy.
jmp short dos5_exit
dos5_busy:
MOV ax, 200h ; No error, busy.
dos5_exit:
ret
dosfn5 endp
;-------- dos function #6: input status --------------------------
; Returns "busy" if no characters waiting to be read.
dosfn6 proc near
call peekchar
mov ax, 200h ; No error, busy.
jz dos6_exit
xor ax, ax ; No error, not busy.
dos6_exit:
ret
dosfn6 endp
;-------- dos function #7: flush input buffer --------------------
; Clears the IBM keyboard input buffer. Since it is a circular
; queue, we can do this without knowing the beginning and end
; of the buffer; all we need to do is set the tail of the queue
; equal to the head (as if we had read the entire queue contents).
; Also resets all the device driver's stuffahead buffers.
dosfn7 proc near
xor ax, ax
mov fnkey.len, ax ; Reset the stuffahead buffers.
mov cprseq.len, ax
mov brkkey.len, ax
mov xlatseq.len, ax
mov ax, abs40
mov es, ax
mov ax, es:buffer_head ; clear queue by making the tail
mov es:buffer_tail, ax ; equal to the head
xor ax, ax ; no error, not busy.
ret
dosfn7 endp
page
if takeBIOS
;--- new_vid_bios -------------------------------------------
; New_vid_bios simply replaces the write_tty call.
; All other calls get sent to the old video bios.
; This gives BIOS ANSI capability.
; However, it takes away the escape character.
; If this is not desired, just tell init to not take over the vector.
new_vid_bios proc
cmp ah, 14
jz nvb_write_tty
jmp dword ptr cs:old_vid_bios
nvb_write_tty:
push cx
mov cl, cs:cur_attrib
; If in graphics mode, BL is new color
call in_g_mode ; returns carry set if text mode
jc nvb_wt_text
mov cs:cur_attrib, bl ; ja?
nvb_wt_text:
int 29h ; write AL
mov cs:cur_attrib, cl ; restore color
pop cx
iret
new_vid_bios endp
endif
;------ int_29 ----------------------------------------------
; Int 29 handles DOS quick-access putchar.
; Last device loaded with attribute bit 4 set gets accessed for
; single-character writes via int 29h instead of via interrupt.
; Must preserve all registers.
; Installed as int 29h by dosfn0 (init).
int_29_buf db ?
int_29 proc near
sti
push ds
push es
push_all
mov cx, 1
mov bx, cs
mov es, bx
mov ds, bx
mov si, offset int_29_buf
mov byte ptr [si], al
call dosfn8
pop_all
pop es
pop ds
iret
int_29 endp
page
;------ dosfn8 -------------------------------------------------------
; Handles writes to the device (with or without verify).
; Called with
; CX = number of bytes to write
; ES:SI = transfer buffer
; DS = CS, so we can access local variables.
dosfn8 proc near
mov f_cptr_seg, es ; save segment of char ptr
; Read the BIOS buffer address/cursor position variables.
mov ax, abs40
mov ds, ax
assume ds:abs40
; Find current video mode and screen size.
mov ax,word ptr crt_mode ; al = crt mode; ah = # of columns
mov cs:video_mode, al
dec ah ; ah = max column
mov cs:max_x, ah
; Find current cursor coordinates.
mov al,active_page
cbw
add ax,ax
xchg bx,ax
mov ax,cursor_posn[bx]
mov cs:cur_coords,AX
; Find video buffer segment address; adjust it
; so the offset is zero; return in AX.
; DS is abs40.
; Find 6845 address.
mov ax, addr_6845
mov cs:port_6845, ax
; Find video buffer address.
MOV AX,crt_start
shr ax, 1
shr ax, 1
shr ax, 1
shr ax, 1
add ah, 0B0h ; assume it's a monochrome card...
CMP cs:video_mode,07
jz d8_gots
add ah, 8 ; but if not mode 7, it's color.
d8_gots:
push cs
pop ds
assume ds:code
mov video_seg, ax
mov es, ax
call xy_to_regs ; Set DX, DI according to cur_coords.
; | If in graphics mode, clear old pseudocursor
call in_g_mode
jc d8_no_cp
call pseudocursor ; write block in xor
d8_no_cp:
mov bx, xlate_tab_ptr ; get pointer to translation table
mov ah, cur_attrib
mov ds, f_cptr_seg ; get segment of char ptr
assume ds:nothing
cld ; make sure we'll increment
; The Inner Loop: 4+12 +4+4 +4+4 +0+15 +4+4 +4+18 = 77 cycles/loop
; on 8088; at 4.77 MHz, that gives 16.1 microseconds/loop.
; At that speed, it takes 32 milliseconds to fill a screen.
; Get a character, put it on the screen, repeat 'til end of line
; or no more characters.
jcxz f_loopdone ; if count = 0, we're already done.
cmp cs:escvector, 0 ; If in middle of an escape sequence,
jnz f_in_escapex ; jump to escape sequence handler.
f_tloop:; | If in graphics mode, jump to alternate loop
; | What a massive kludge! A better approach would have been
; | to collect characters for a "write n chars" routine
; | which would handle both text and graphics modes.
call in_g_mode
jc f_t_cloop
jmp f_g_cloop
f_t_cloop:
LODSB ; get char! (al = ds:[si++])
cmp al, 28 ; is it a control char?
jb f_control ; maybe...
f_t_nctl:
seg_cs
xlat
STOSW ; Put Char! (es:[di++] = ax)
dec dx ; count down to end of line
loopnz f_t_cloop ; and go back for more.
jz f_t_at_eol ; at end of line; maybe do a crlf.
jmp short f_loopdone
f_looploop:
f_ansi_exit: ; in case we switched into
loopnz f_tloop ; a graphics mode
f_t_at_eol:
jz f_at_eol
f_loopdone:
;--------- All done with write request -----------
; DI is cursor address; cursor position in cur_y, dl.
mov ax, cs
mov ds, ax ; get our segment back
assume ds:code
; Restore cur_x = max_x - dx + 1.
mov al, max_x
inc al
sub al, dl
mov cur_x, al
; Set cursor position; cursor adr in DI; cursor pos in cur_x,cur_y
call set_pseudocursor
; Return to DOS.
xor ax, ax ; No error, not busy.
ret
;---- handle control characters ----
; Note: cur_x is not kept updated in memory, but can be
; computed from max_x and dx.
; Cur_y is kept updated in memory.
f_control:
cmp al, 27 ; Is it an escape?
jz f_escapex
cmp al, 13 ; carriage return?
jz f_cr
cmp al, 10 ; line feed?
jz f_lf
cmp al, 9 ; tab?
jz f_tabx
cmp al, 8 ; backspace?
jz f_bs
cmp al, 7 ; bell?
jz f_bell
jmp f_nctl ; then it is not a control char.
f_tabx: jmp f_tab
f_escapex:
jmp f_escape
f_in_escapex:
jmp f_in_escape
f_bs: ;----- Handle backspace -----------------
; Moves cursor back one space without erasing. No wraparound.
cmp dl, cs:max_x ; wrap around to previous line?
ja fbs_wrap ; yep; disallow it.
dec di ; back up one char & attrib,
dec di
inc dx ; and note one more char left on line.
fbs_wrap:
jmp f_looploop
f_bell: ;----- Handle bell ----------------------
; Use BIOS to do the beep. DX is not changed, as bell is nonprinting.
call beep
or al, al ; clear z
; old (more portable) version:
; mov ax, 0e07h ; "write bell to tty simulator"
; mov bx, 0 ; "page zero, color black"
; int 10h ; call BIOS
; mov ah, cs:cur_attrib ; restore current attribute
; mov bx, cs:xlate_tab_ptr ; restore translate table address
; or al, al ; al still 7; this clears Z.
jmp f_looploop ; Let main loop decrement cx.
f_cr: ;----- Handle carriage return -----------
; di -= cur_x<<1; set di= address of start of line
; dx=max_x+1; set bx= chars left in line
mov al, cs:max_x
inc al
sub al, dl ; Get cur_x into ax.
mov ah, 0
sub di, ax
sub di, ax
mov dl, cs:max_x ; Full line ahead of us.
inc dx
mov ah, cs:cur_attrib ; restore current attribute
or al, 1 ; clear z
jmp f_looploop ; and let main loop decrement cx
f_at_eol:
;----- Handle overrunning right end of screen -------
; cx++; compensate for double loop
; if (!wrap_flag) { dx++; di-=2; }
; else do_crlf;
inc cx
test cs:wrap_flag, 1
jnz feol_wrap
dec di
dec di
inc dx
jmp f_looploop
feol_wrap:
; dx=max_x+1; set bx= chars left in line
; di -= 2*(max_x+1);
; do_lf
mov dl, cs:max_x
inc dx
sub di, dx
sub di, dx
; fall thru to line feed routine
f_lf: ;----- Handle line feed -----------------
; if (cur_y >= max_y) scroll; scroll screen up if needed
; else { cur_y++; di += max_x<<1; else increment Y
mov al, cs:max_y
cmp cs:cur_y, al
jb flf_noscroll
call scroll_up ; preserves bx,cx,dx,si,di
jmp short flf_done
flf_noscroll:
inc cs:cur_y
mov al, cs:max_x
mov ah, 0
inc ax
add ax, ax
add di, ax
flf_done:
mov ah, cs:cur_attrib ; restore current attribute
or al, 1 ; clear z
jmp f_looploop ; and let main loop decrement cx
f_tab: ;----- Handle tab expansion -------------
; Get cur_x into al.
mov al, cs:max_x
inc al
sub al, dl
; Calculate number of spaces to output.
push cx ; save cx
mov ch, 0
mov cl, al ; get zero based x coordinate
and cl, 7
neg cl
add cl, 8 ; 0 -> 8, 1 -> 8, ... 7 -> 1
sub dx, cx ; update chars-to-eol, maybe set z
pushf ; || save Z for main loop
; ah is still current attribute. Move CX spaces to the screen.
mov al, ' '
call in_g_mode ; | graphics mode
jnc f_tab_putc ; |
REP STOSW
popf ; || restore Z flag for main loop test
pop cx ; restore cx
jmp f_looploop ; Let main loop decrement cx.
;--------------- graphics mode support -----------------------
f_tab_putc: ; graphics mode- call putc to put the char
add dx, cx ; move back to start of tab
f_tp_lp:
call putchar
dec dx ; go to next cursor position
loop f_tp_lp
popf ; Z set if wrapped around EOL
pop cx
jmp f_looploop
;---- in_g_mode -------------
; Returns Carry set if not in a graphics mode.
; Preserves all registers.
in_g_mode proc near
cmp cs:video_mode, 4
jb igm_stc
cmp cs:video_mode, 7
jz igm_stc
clc
ret
igm_stc:
stc
ret
in_g_mode endp
;---- Where to go when a character turns out not to be special
f_nctl:
f_not_ansi:
call in_g_mode
jnc f_g_nctl ; graphics mode
f_jmptnctl:
jmp f_t_nctl ; text mode
;---- Alternate main loop for graphics mode ----
f_g_cloop:
LODSB ; get char! (al = ds:[si++])
cmp al, 28 ; is it a control char?
jb f_g_control ; maybe...
f_g_nctl:
seg_cs
xlat
call putchar
dec dx ; count down to end of line
loopnz f_g_cloop ; and go back for more.
jz f_g_at_eol ; at end of line; maybe do a crlf.
jmp f_loopdone
f_g_control: jmp f_control
f_g_at_eol: jmp f_at_eol
;---- putchar ------------------------------------------------
; Writes char AL, attribute AH to screen at (max_x+1-dl), cur_y.
; On entry, registers set up as per xy_to_regs.
; Preserves all registers.
putchar proc near
push dx
push cx
push bx
push ax
; 1. Set cursor position.
mov al, cs:max_x
inc al
sub al, dl
mov cs:cur_x, al
mov dx, cs:cur_coords ; get X & Y into DX
xor bx, bx ; choose dpy page 0
mov ah, 2 ; chose "Set Cursor Position"
int 10h ; call ROM BIOS
; 2. Write char & attribute.
mov cx, 1
pop ax ; get char in AL
push ax
mov bl, ah ; attribute in BL
mov bh, 0
mov ah, 9
int 10h
pop ax
pop bx
pop cx
pop dx
ret
putchar endp
;---- set_pseudocursor ------------
; If in graphics mode, set pseudocursor, else set real cursor.
; Destroys DS!!!!
set_pseudocursor proc near
call in_g_mode
jnc pseudocursor
; old (more portable, but slower) version
; mov dx, cur_coords ; get X & Y into DX
; xor bx, bx ; choose dpy page 0
; mov ah, 2 ; chose "Set Cursor Position"
; int 10h ; call ROM BIOS
; Write directly to 6845 cursor address register.
mov bx, di
shr bx, 1 ; convert word index to byte index
mov dx, port_6845
mov al, 0eh
out dx, al
jmp $+2
inc dx
mov al, bh
out dx, al
jmp $+2
dec dx
mov al, 0fh
out dx, al
jmp $+2
inc dx
mov al, bl
out dx, al
; Set cursor position in low memory.
assume ds:abs40
mov ax, abs40
mov ds, ax
; Does anybody ever use anything but page zero?
; mov al,active_page
; cbw
; add ax,ax
; xchg bx,ax
mov ax, cs:cur_coords
mov cursor_posn,ax
ret
assume ds:code
set_pseudocursor endp
;---- pseudocursor --------------------------------------------------
; Writes a color 15 block in XOR at the current cursor location.
; Preserves DS, ES, BX, CX, DX, SI, DI.
; Should be disableable- the pseudocursor slows down single-char
; writes by a factor of three.
pseudocursor proc near
mov ax, 8f16h ; xor, color 15, ^V (small block)
call putchar
ret
pseudocursor endp
;--------------- end of graphics mode support --------------------
dosfn8 endp
;--- get_blank_attrib ------------------------------------------------
; Determine new attribute and character for a new blank region.
; Use current attribute, just disallow blink and underline.
; (Pretty strange way to do it. Might want to disallow rev vid, too.)
; Returns result in AH, preserves all other registers.
get_blank_attrib proc near
mov ah, 0
call in_g_mode
jnc gb_aok ; if graphics mode, 0 is bkgnd
mov ah, cs:cur_attrib
and ah, 7fh ; disallow blink
cmp cs:video_mode, 7 ; monochrome?
jnz gb_aok
cmp ah, 1 ; underline?
jnz gb_aok
mov ah, 7 ; yep- set it to normal.
gb_aok: ret
get_blank_attrib endp
;---- scroll_up ---------------------------------------------------
; Scroll screen up- preserves ax, bx, cx, dx, si, di, ds, es.
; Moves screen up 1 line, fills the last line with blanks.
; Attribute of blanks is the current attribute sans blink and underline.
scroll_up proc near
push ax
push bx
push cx
push dx
call get_blank_attrib
mov bh, ah ; color to use on new blank areas
mov al, 1 ; AL is number of lines to scroll.
mov ah, 6 ; BIOS: scroll up
mov cl, 0 ; upper-left-x of data to scroll
mov ch, 0 ; upper-left-y of data to scroll
mov dl, cs:max_x ; lower-rite-x
mov dh, cs:max_y ; lower-rite-y (zero based)
int 10h ; call BIOS to scroll a rectangle.
pop dx
pop cx
pop bx
pop ax
ret
scroll_up endp
;---- lookup -----------------------------------------------
; Called by getchar, peekchar, and key to see if a given key has
; been redefined.
; Sets AH to zero if AL is not zero (i.e. if AX is not a function key).
; Returns with Z cleared if no redefinition; otherwise,
; Z is set, SI points to redefinition string, CX is its length.
; Preseves AL, all but CX and SI.
; Redefinition table organization:
; Strings are stored in reversed order, first char last.
; The word following the string is the character to be replaced;
; the next word is the length of the string sans header.
; param_end points to the last byte used by the parameter buffer;
; redef_end points to the last word used by the redef table.
lookup proc near
mov si, redef_end ; Start at end of table, move down.
or al, al
jz lu_lp
mov ah, 0 ; clear extraneous scan code
lu_lp: cmp si, param_end
jbe lu_notfound ; If below redef table, exit.
mov cx, [si]
cmp ax, [si-2] ; are you my mommy?
jz lu_gotit
sub si, 4
sub si, cx ; point to next header
jmp lu_lp
lu_notfound:
or si, si ; clear Z
jmp short lu_exit
lu_gotit:
sub si, 2
sub si, cx ; point to lowest char in memory
cmp al, al ; set Z
lu_exit:
ret
lookup endp
;---- searchbuf --------------------------------------------
; Called by getchar and peekchar to see if any characters are
; waiting to be gotten from sources other than BIOS.
; Returns with Z set if no chars found, BX=keybuf & SI=keybuf.len otherwise.
searchbuf proc near
; Search the stuffahead buffers.
mov cx, 4 ; number of buffers to check for chars
mov bx, offset fnkey - 4
sbloop: add bx, 4 ; point to next buffer record
mov si, [bx].len
or si, si ; empty?
loopz sbloop ; if so, loop.
ret
searchbuf endp
;---- getchar -----------------------------------------------
; Returns AL = next char.
; Trashes AX, BX, CX, BP, SI.
getchar proc near
gc_searchbuf:
; See if any chars are waiting in stuffahead buffers.
call searchbuf
jz gc_trykbd ; No chars? Try the keyboard.
; A nonempty buffer was found.
dec [bx].len
dec si
mov bp, [bx].adr ; get pointer to string
mov al, byte ptr ds:[bp][si]; get the char
; Recognize function key sequences, move them to highest priority
; queue.
sub si, 1 ; set carry if si=0
jc gc_nofnkey ; no chars left -> nothing to protect.
cmp bx, offset fnkey
jz gc_nofnkey ; already highest priority -> done.
or al, al
jnz gc_nofnkey ; nonzero first byte -> not fnkey.
; Found a function key; move it to highest priority queue.
dec [bx].len
mov ah, byte ptr ds:[bp][si]; get the second byte of fn key code
gc_fnkey:
mov fnkey.len, 1
mov fnkeybuf, ah ; save it.
gc_nofnkey:
; Valid char in AL. Return with it.
jmp short gcdone
gc_trykbd:
; Actually get a character from the keyboard.
mov ah, 0
int 16h ; BIOS returns with char in AX
; If it's Ctrl-break, it has already been taken care of.
or ax, ax
jz gc_trykbd
; Look in the reassignment table to see if it needs translation.
call lookup ; Z=found; CX=length; SI=ptr
jnz gc_noredef
; Okay; set up the reassignment, and run thru the translation code.
mov xlatseq.len, cx
mov xlatseq.adr, si
jmp gc_searchbuf
gc_noredef:
; Is it a function key?
cmp al, 0
jz gc_fnkey ; yep- special treatment.
gcdone: ret ; with character in AL.
getchar endp
;---- peekchar -----------------------------------------------
; Returns Z if no character ready, AL=char otherwise.
; Trashes AX, BX, CX, BP, SI.
peekchar proc near
pc_searchbuf:
call searchbuf
jz pc_trykbd ; No chars? Try the keyboard.
; A nonempty buffer was found.
dec si
mov bp, [bx].adr ; get pointer to string
mov al, byte ptr ds:[bp][si]; get the char
; Valid char from buffer in AL. Return with it.
jmp short pcdone
pc_trykbd:
; Actually peek at the keyboard.
mov ah, 1
int 16h ; BIOS returns with char in AX
jz pcexit
; If it's control-break, it's already been taken care of.
or ax, ax
jnz pc_notbrk
mov ah, 0
int 16h ; so get rid of it!
jmp short pc_trykbd
pc_notbrk:
; Look in the reassignment table to see if it needs translation.
call lookup ; Z=found; CX=length; SI=ptr
jnz pcdone ; Nope; just return the char.
; Okay; get the first code to be returned.
add si, cx
mov al, [si-1]
pcdone: or ah, 1 ; NZ; char ready!
pcexit: ret ; with character in AL, Z true if no char waiting.
peekchar endp
;---- beep ------------------------------------------------------
; Beep speaker; period given by beep_div, duration by beep_len.
; Preserves all registers.
beep_div dw 1300 ; fairly close to IBM beep
beep_len dw 3 ; 3/18 sec- shorter than IBM
beep proc near
push_all
mov al, 10110110b ; select 8253
mov dx, 43h ; control port address
out dx, al
dec dx ; timer 2 address
mov ax, cs:beep_div
jmp $+2
out dx, al ; low byte of divisor
xchg ah, al
jmp $+2
out dx, al ; high byte of divisor
mov dx, 61h
jmp $+2
in al, dx ; get current value of control bits
push ax
or al, 3
jmp $+2
out dx, al ; turn speaker on
; Wait for desired duration by monitoring time-of-day 18 Hz clock
push es
mov ax, abs40
mov es, ax
assume es:abs40
mov bx, timer_low
mov cx, -1
beeplp: mov ax, timer_low
sub ax, bx
cmp ax, cs:beep_len
jg beepover
loop beeplp
beepover:
pop es
assume es:code
; Turn off speaker
pop ax
and al, not 3 ; turn speaker off
out dx, al
pop_all
ret
beep endp
CODE ends
end ; of nansi.asm
page 66, 132
;----- nansi_f.asm ---------------------------------------------
; The ANSI control subroutines.
; (C) 1986 Daniel Kegel, Pasadena, CA
; May be distributed for educational and personal use only
; Each routine is called with the following register usage:
; AX = max(1, value of first parameter)
; Z flag is set if first parameter is zero.
; CX = number of paramters
; SI = offset of second parameter from CS
; DS = CS
; ES:DI points to the current location on the memory-mapped screen.
; DX is number of characters remaining on the current screen line.
; The control routine is free to trash AX, BX, CX, SI, and DS.
; It must preserve ES, and can alter DX and DI if it wants to move the
; cursor.
;
; Revisions:
; 19 Aug 85: Fixed horrible bug in insert/delete line.
; 26 Aug 85: Fixed simple limit-to-one-too-few-lines bug in ins/del line;
; anyway, it inserts 24 lines when on line 2 now. Whether it's fixed...
; 4 Sept 85: Fixed bug created on 26 Aug 85; when limiting ins/del line
; count, we are clearing, not scrolling; fixed BIOS call to reflect this.
; 30 Jan 86: Added EGA cursor patch
; 31 Jan 86: Disabled insert/delete char in graphics modes
; Implemented keyboard redefinition reset
; 1 Feb 86: added video_mode and max_x test after mode set
;----------------------------------------------------------------
include nansi_d.asm
; To nansi_p.asm
public ansi_fn_table
; From nansi.asm
extrn port_6845:word
extrn cur_coords:word, saved_coords:word
extrn cur_x:byte, max_x:byte
extrn cur_y:byte, max_y:byte
extrn cur_attrib:byte, wrap_flag:byte
extrn xy_to_regs:near
extrn get_blank_attrib:near
extrn xlate_tab_ptr:word
extrn cpr_esc:byte, cprseq:word
extrn video_mode:byte
extrn lookup:near
extrn in_g_mode:near
; from nansi_p.asm
extrn param_buffer:word ; used in keyboard programming
extrn param_end:word
extrn redef_end:word
keybuf struc ; used in making cpr sequence
len dw ?
adr dw ?
keybuf ends
ABS40 segment at 40h
org 1ah
buffer_head dw ? ; Used in 'flush input buffer' dos call.
buffer_tail dw ?
org 49h
crt_mode db ?
crt_cols dw ?
crt_len dw ?
crt_start dw ?
cursor_posn dw 8 dup (?)
cursor_mode dw ?
active_page db ?
addr_6845 dw ?
crt_mode_set db ?
crt_palette db ?
ABS40 ends
code segment byte public 'CODE'
assume cs:code, ds:code
;----- byteout ---------------------------------------------------
; Converts al to a decimal ASCII string (in 0..99),
; stores it at ES:DI++. Returns DI pointing at byte after last digit.
; Destroys DL.
byteout proc near
aam
add ax, 3030h
xchg ah, al
stosb
xchg ah, al
stosb
ret
byteout endp
;----- ansi_fn_table -----------------------------------
; Table of offsets of terminal control subroutines in order of
; the character that invokes them, @..Z, a..z. Exactly 53 entries.
; All the subroutines are defined below in this module.
ansi_fn_table label word
dw ic, cup, cdn, cfw, cbk ; @, A, B, C, D
dw nul, nul, nul, hvp, nul ; E, F, G, H, I
dw eid, eil, il, d_l, nul ; J, K, L, M, N
dw nul, dc, nul, nul, nul ; O, P, Q, R, S
dw nul, nul, nul, nul, nul ; T, U, V, W, X
dw nul, nul ; Y, Z
dw nul, nul, nul, nul, nul ; a, b, c, d, e
dw hvp, nul, sm, nul, nul ; f, g, h, i, j
dw nul, rm, sgr, dsr, nul ; k, l, m, n, o
dw key, nul, nul, scp, nul ; p, q, r, s, t
dw rcp, nul, nul, nul, xoc ; u, v, w, x, y
dw nul ; z
ansi_functions proc near ; set return type to NEAR
;----- nul ---------------------------------------------
; No-action ansi sequence; called when unknown command given.
nul: ret
;----- Cursor Motion -----------------------------------------------
;-- cursor to y,x
hvp: or al, al ; First parameter is desired Y coordinate.
jz hvp_yok
dec ax ; Convert to zero-based coordinates.
hvp_yok:mov cur_y, al
; Get second parameter, if it is there, and set X with it.
xor ax, ax
cmp cx, 2 ; was there a second parameter?
jb hvp_xok
lodsb ; yes.
or al, al
jz hvp_xok
dec ax ; convert to zero-based coordinates.
hvp_xok:mov cur_x, al
; Clip to maximum coordinates.
hvp_set:
mov ax, cur_coords ; al = x, ah = y
cmp al, max_x
jbe hvp_sxok
mov al, max_x
mov cur_x, al
hvp_sxok:
cmp ah, max_y
jbe hvp_syok
mov al, max_y
mov cur_y, al
hvp_syok:
; Set values of DX and DI accordingly.
call xy_to_regs
ret
;-- cursor forward --
cfw: add cur_x, al
jmp hvp_set
;-- cursor back -----
cbk: sub cur_x, al
jae cbk_ok
mov cur_x, 0
cbk_ok: jmp hvp_set
;-- cursor down -----
cdn: add cur_y, al
jmp hvp_set
;-- cursor up -------
cup: sub cur_y, al
jae cup_ok
mov cur_y, 0
cup_ok: jmp hvp_set
;-- save cursor position --------------------------------------
scp: mov ax, cur_coords
mov saved_coords, ax
ret
;-- restore cursor position -----------------------------------
rcp: mov ax, saved_coords
mov cur_coords, ax
jmp hvp_set ; Clip in case we have switched video modes.
;-- set graphics rendition ------------------------------------
; Modifies the color in which new characters are written.
sgr: dec si ; get back pointer to first parameter
or cx, cx ; Did he give any parameters?
jnz sgr_loop
mov byte ptr [si], 0 ; no parameters, so fake
inc cx ; one with the default value.
; For each parameter
sgr_loop:
lodsb ; al = next parameter
; Search color table
push cx
mov cx, colors
mov bx, offset color_table-3
sgr_search:
add bx, 3
cmp al, byte ptr [bx]
loopnz sgr_search ; until match found or done
jnz sgr_loopx
; If parameter named a known color, set the current
; color variable.
mov ax, [bx+1]
and cur_attrib, al
or cur_attrib, ah
sgr_loopx:
pop cx
loop sgr_loop ; until no more parameters.
ret
;-- erase in line ----------------------------------------
; Uses BIOS to scroll away a one-line rectangle
eil: push dx
mov cx, cur_coords
mov dh, ch
jmp short scrollem
;-- erase in display -------------------------------------
; Uses BIOS to scroll away all of display
eid: cmp al, 2
jnz eid_ignore ; param must be two
if cls_homes_too
mov cur_coords, 0
call xy_to_regs
endif
push dx
xor cx, cx
mov dh, max_y
scrollem:
call get_blank_attrib
mov bh, ah
mov dl, max_x
mov ax, 600h
int 10h
pop dx
eid_ignore:
ret
;-- device status report --------------------------------
; Stuffs an escape, a left bracket, current Y, semicolon, current X,
; a capital R, and a carriage return into input stream.
; The coordinates are 1 to 3 decimal digits each.
dsr: push di
push dx
push es
mov ax, cs
mov es, ax
std ; Store string in reversed order for fun
mov di, offset cpr_esc - 2
mov al, cur_y
inc al ; convert to one-based coords
call byteout ; row
mov al, ';' ; ;
stosb
mov al, cur_x
inc al ; convert to one-based coords
call byteout ; column
mov al, 'R' ; R ANSI function 'Cursor Position Report'
stosb
mov al, 13
mov word ptr cprseq.adr, di ; save pointer to last char in string
stosb ; send a carriage return, too
mov ax, offset cpr_esc
sub ax, di ; ax is # of characters in string
mov word ptr cprseq.len, ax ; pass info to the getchar routine
cld
pop es
pop dx
pop di
ret
;-- keyboard reassignment -------------------------------
; Key reassignment buffer is between param_end and redef_end+2, exclusive.
; When it shrinks or grows, param_end is moved.
; Format of an entry is as follows:
; highest address -> length:word (may be 0)
; key to replace:word (either hi or low byte is zero)
; .
; . new key value, "length" bytes long
; .
; lowest address -> next entry, or free space.
; If no arguments are given, keyboard is reset to default condition.
; Otherwise, first parameter (or first two, if first is zero) defines
; the key whose value is to be changed, and the following parameters
; define the key's new, possibly zero-length, value.
key:
; Is this a reset?
or cx, cx
jz key_init
; Get the first (or first two) parameters
cld
dec si ; point to first param
dec cx ; Assume it's a fn key, get two params
dec cx
lodsw
or al, al ; Is it a function key?
jz key_fnkey
; It's not a function key- put second param back
inc cx
dec si
key_fnkey:
; Key to redefine now in AX. If it's already redefined,
; lookup will set Z, point SI to redef string, set CX to its length.
push di
push es
push cx
push si
std ; moving up, must move from top down
push ds
pop es ; string move must have ES=DS
call lookup ; rets Z if redefined...
jnz key_newkey
; It's already defined. Erase its old definition- i.e., move
; region param_end+1..SI-1 upwards CX+4 bytes, add CX+4 to param_end.
add cx, 4
mov bp, param_end ; save old value in bp...
add param_end, cx
dec si ; start at (SI-1)
mov di, si
add di, cx ; move to (start + CX+4)
mov cx, si
sub cx, bp ; length of region old_param_end+1..start
rep movsb
key_newkey:
; Key not redefined. See if there's enough room to redefine it.
pop si ; get back pointer to redef string
pop cx ; get back number of bytes in redef string
mov di, param_end ; hi byte of new redef record, hi byte of len
sub di, 4 ; hi byte of new data field
mov bx, di
sub bx, cx ; hi byte of remaining buffer space
sub bx, 16 ; better be at least 16 bytes room
cmp bx, param_buffer
jb key_popem ; nope- forget it.
; Nothing in the way now!
mov [di+3], cx ; save length field
mov [di+1], ax ; save name field
jcxz key_nullstring
key_saveloop: ; save data field
movsb
add si, 2 ; input string ascending, output descending
loop key_saveloop
key_nullstring:
mov param_end, di ; save adr of new hi byte of free area
key_popem:
pop es
pop di
key_exit:
cld
ret
key_init:
; Build the default redefinition table:
; control-printscreen -> control-P
push es
push ds
pop es
std
mov di, redef_end
mov ax, 1
stosw
mov ax, 7200h ; control-printscreen
stosw
mov al, 16 ; control P
stosb
mov param_end, di ; save new bottom of redef table
pop es
jmp key_exit
;---- Delete/Insert Lines -------------------------------
; AL is number of lines to delete/insert.
; Preserves DX, DI; does not move cursor.
d_l: ; Delete lines.
mov ah, 6 ; BIOS: scroll up
jmp short il_open
il: ; Insert lines.
mov ah, 7 ; BIOS: scroll down
il_open:
; Whether inserting or deleting, limit him to (max_y - cur_y) lines;
; if above that, we're just clearing; set AL=0 so BIOS doesn't burp.
mov bh, max_y
sub bh, cur_y
cmp al, bh
jbe il_ok ; DRK 9/4...
mov al, 0 ; he tried to move too far
il_ok:
push ax
call get_blank_attrib
mov bh, ah ; color to use on new blank areas
pop ax ; AL is number of lines to scroll.
mov cl, 0 ; upper-left-x of data to scroll
mov ch, cur_y ; upper-left-y of data to scroll
push dx
mov dl, max_x ; lower-rite-x
mov dh, max_y ; lower-rite-y (zero based)
int 10h ; call BIOS to scroll a rectangle.
pop dx
ret ; done.
;-- Insert / Delete Characters ----------------------------
; AL is number of characters to insert or delete.
; Preserves DX, DI; does not move cursor.
ic: mov ch, 1 ; 1 => swap dest & source below
jmp short dc_ch
dc: mov ch, 0
dc_ch:
call in_g_mode
jnc dc_ret ; | if in graphics mode, ignore.
; AL = number of chars to ins or del (guarenteed nonzero).
; Limit him to # of chars left on line.
cmp al, dl
jbe dc_cok
mov al, dl
dc_cok:
push di ; DI is current address of cursor
xchg ax, cx ; CX gets # of chars to ins/del
mov bp, cx ; BP gets # of columns to clear.
; Set up source = destination + cx*2, count = dx - cx
mov ch, 0 ; make it a word
mov si, di
add si, cx
add si, cx
neg cl
add cl, dl
mov ch, 0 ; CX = # of words to transfer
cld ; REP increments si & di
; If this is an insert, then flip transfer around in both ways.
test ah, 1
jz dc_noswap
xchg di, si ; source <-> dest
std ; up <-> down
mov ax, cx ; make move over same range
dec ax
add ax, ax ; AX=dist from 1st to last byte.
add di, ax ; Start transfer at high end of block
add si, ax ; instead of low end.
dc_noswap:
; Move those characters.
push es
pop ds
rep movsw
mov cx, bp
; Figure out what color to make the new blanks.
call get_blank_attrib
mov al, ' '
; Blank out vacated region.
rep stosw
; All done.
cld ; restore normal REP state and
pop di ; cursor address.
dc_ret: ret
;---- set / reset mode ---------------------------------------
; Sets graphics/text mode; also sets/resets "no wrap at eol" mode.
sm: mov cl, 0ffh ; set
sm_rs:
; Is it "wrap at eol" ?
cmp al, 7
jnz sm_notwrap
mov wrap_flag, cl ; true = wrap at EOL
jmp short sm_done
sm_notwrap:
; Is it "set highest number of screen lines available"?
cmp al, 43
jnz sm_video
; Only valid for the Enhanced Graphics Adaptor on
; a monochrome display or an enhanced color display.
; Test presence of EGA by calling BIOS fn 12h.10h.
mov ah, 12h
mov bx, 0ff10h
int 10h ; bh=0-1, bl=0-3 if EGA
test bx, 0FEFCH
jnz sm_done ; sorry, charlie
; mov port_6845, 3d4h
; mov al, video_mode
; and al, 7
; cmp al, 7 ; monochrome monitor?
; jnz sm_colormon
; mov byte ptr port_6845, low(3b4h)
;sm_colormon:
; 43 line mode only allowed in text modes, for now.
call in_g_mode
jnc sm_done
mov ah, 0 ; "Set video mode"
mov al, video_mode ; Re-init current mode
int 10h
mov ax,1112h ; Load 8x8 font
mov bl,0 ; (instead of 8x14)
int 10h
mov ax, 1200h ; Load new printscreen
mov bl, 20h
int 10h
mov ah,1
mov cx,0707h ; (Load cursor scan lines)
int 10h
; | Patch; this gotten by painful observation of
; | IBM's professional editor. I think there's a
; | documented bug in Video Bios's "load cursor scan line"
; | call; try looking in latter 1985 PC Tech Journal.
mov dx, port_6845 ; '6845' command reg
mov al, 10
out dx, al
jmp $+2
inc dx
mov al, 7
out dx, al ; set cursor start line
; Assume that gets us 43 lines.
mov max_y, 42
jmp short sm_home
sm_video:
; It must be a video mode. Call BIOS.
mov ah, 0 ; "set video mode"
int 10h
; Assume that gets us 25 lines.
mov max_y, 24
sm_home:
; Read the BIOS buffer address/cursor position variables.
mov ax, abs40
push ds
mov ds, ax
assume ds:abs40
; Find current video mode and screen size.
mov ax,word ptr crt_mode ; al = crt mode; ah = # of columns
pop ds
mov video_mode, al
dec ah ; ah = max column
mov max_x, ah
; Since cursor may end up in illegal position, it's best to
; just go home after switching video modes.
mov cur_coords, 0
call xy_to_regs
sm_done:
ret
rm: mov cl, 0 ; reset
jmp sm_rs
;------- Output Character Translation ----------------------
; A decidedly nonstandard function, possibly useful for editing files
; intended to be printed by daisywheel printers with strange wheels.
; (The letter 'y' was chosen to conflict with the VT100 self-test command.)
; Usage: ESC [ #1;#2 y
; where #1 is the character to redefine
; #2 is the new display value
; If only ESC [ #1 y is sent, character #1 is reset to its default value.
; If only ESC [ y is sent, the entire table is reset to the default value.
; (If only ESC [ #1; y is sent, character #1 is set to zero... sigh.)
xoc: ; Xlate output character
mov bx, xlate_tab_ptr
jcxz xoc_reset ; if no parameters, reset table to 1:1
dec si ; point to first parameter
lodsw ; first parameter to AL, second to AH
dec cx ; is parameter count 1?
jnz xoc_bothparams
mov ah, al ; if only one param, reset that char.
xoc_bothparams:
add bl, al
adc bh, 0 ; bx points to entry for char AL
mov byte ptr [bx], ah ; change that entry
xoc_done:
ret
xoc_reset:
; Fill table with default values- i.e. 0, 1, 2, ... 255.
xor ax, ax
xoc_loop:
mov byte ptr [bx], al
inc bx
inc al
jnz xoc_loop
jmp xoc_done
ansi_functions endp ; end dummy procedure block
;-------- Color table -----------------------------------------
; Used in "set graphics rendition"
colors equ 22 ; number of colors in table
color_table:
db 0, 000h,07h ; all attribs off; normal.
db 1, 0ffh,08h ; bold
db 4, 0f8h,01h ; underline
db 5, 0ffh,80h ; blink
db 7, 0f8h,70h ; reverse
db 8, 088h,00h ; invisible
db 30,0f8h,00h ; black foreground
db 31,0f8h,04h ; red
db 32,0f8h,02h ; green
db 33,0f8h,06h ; yellow
db 34,0f8h,01h ; blue
db 35,0f8h,05h ; magenta
db 36,0f8h,03h ; cyan
db 37,0f8h,07h ; white
db 40,08fh,00h ; black background
db 41,08fh,40h ; red
db 42,08fh,20h ; green
db 43,08fh,60h ; yellow
db 44,08fh,10h ; blue
db 45,08fh,50h ; magenta
db 46,08fh,30h ; cyan
db 47,08fh,70h ; white
code ends
end ; of nansi_f.asm
page 66, 132
;----- nansi_p.asm --------------------------------------------------------
; A state machine implementation of the mechanics of ANSI terminal control
; string parsing.
; (C) 1986 Daniel Kegel, Pasadena, CA
; May be distributed for educational and personal use only
;
; Entered with a jump to f_escape when driver finds an escape, or
; to f_in_escape when the last string written to this device ended in the
; middle of an escape sequence.
;
; Exits by jumping to f_ANSI_exit when an escape sequence ends, or
; to f_not_ANSI when a bad escape sequence is found, or (after saving state)
; to f_loopdone when the write ends in the middle of an escape sequence.
;
; Parameters are stored as bytes in param_buffer. If a parameter is
; omitted, it is stored as zero. Each character in a keyboard reassignment
; command counts as one parameter.
;
; When a complete escape sequence has been parsed, the address of the
; ANSI routine to call is found in ansi_fn_table.
;
; Register usage during parsing:
; DS:SI points to the incoming string.
; CX holds the length remaining in the incoming string.
; ES:DI points to the current location on the memory-mapped screen.
; DX is number of characters remaining on the current screen line.
; BX points to the current paramter byte being assembled from the incoming
; string. (Stored in cur_parm_ptr between device driver calls, if needed.)
;
; The registers are set as follows before calling the ANSI subroutine:
; AX = max(1, value of first parameter)
; CX = number of paramters
; SI = offset of second parameter from CS
; DS = CS
; ES:DI points to the current location on the memory-mapped screen.
; DX is number of characters remaining on the current screen line.
; The subroutine is free to trash AX, BX, CX, SI, and DS.
; It must preserve ES, and can alter DX and DI if it wants to move the
; cursor.
;
; Revision history:
; 7 July 85: created by DRK
;------------------------------------------------------------------------
; From nansi.asm
extrn f_not_ANSI:near ; exit: abort bad ANSI cmd
extrn f_ANSI_exit:near ; exit: good cmd done
extrn f_loopdone:near ; exit: ran out of chars. State saved.
extrn escvector:word ; saved state: where to jump
extrn cur_parm_ptr:word ; saved state: where to put next param
extrn string_term:byte ; saved state: what ends string
extrn cur_x:byte, max_x:byte ; 0 <= cur_x <= max_x
extrn cur_attrib:byte ; current color/attribute
extrn xlate_tab_ptr:word
; from nansi_f.asm
extrn ansi_fn_table:word ; ANSI subroutine table
; Used in nansi.asm
public f_escape ; entry: found an escape
public f_in_escape ; entry: restore state, keep parsing
; Used in nansi_i.asm and nansi_f.asm
public param_buffer, param_end, redef_end
code segment byte public 'CODE'
assume cs:code
; More saved state
in_num db ? ; true if between a digit and a semi in parse
param_buffer dw 3000h ; address of first byte free for new params
param_end dw 3030h ; address of end of free area
redef_end dw 3030h ; address of end of redefinition area
; These initialized values are only for debugging
;----- next_is -------------------------------------------------------
; Next_is is used to advance to the next state. If there are characters
; left in the input string, we jump immediately to the new state;
; otherwise, we shut down the recognizer, and wait for the next call
; to the device driver.
next_is macro statename
loop statename
mov ax, offset statename
jmp sleep
endm
;----- sleep --------------------------------------------------------
; Remember bx and next state, then jump to device driver exit routine.
; Device driver will re-enter at f_in_escape upon next invocation
; because escvector is nonzero; parsing will then be resumed.
sleep: mov cs:cur_parm_ptr, bx
mov cs:escvector, ax
jmp f_loopdone
;----- f_in_escape ---------------------------------------------------
; Main loop noticed that escvector was not zero.
; Recall value of BX saved when sleep was jumped to, and jump into parser.
f_in_escape:
mov bx, cs:cur_parm_ptr
jmp word ptr cs:escvector
fbr_syntax_error_gate: ; jumped to from inside f_bracket
jmp syntax_error
;----- f_escape ------------------------------------------------------
; We found an escape. Next character should be a left bracket.
f_escape:
next_is f_bracket
;----- f_bracket -----------------------------------------------------
; Last char was an escape. This one should be a [; if not, print it.
; Next char should begin a parameter string.
f_bracket:
lodsb
cmp al, '['
jnz fbr_syntax_error_gate
; Set up for getting a parameter string.
mov bx, cs:param_buffer
mov byte ptr cs:[bx], 0
mov cs:in_num, 0
next_is f_get_args
;----- f_get_args ---------------------------------------------------
; Last char was a [. If the current char is a '=' or a '?', eat it.
; In any case, proceed to f_get_param.
; This is only here to strip off the strange chars that follow [ in
; the SET/RESET MODE escape sequence.
f_get_args:
lodsb
cmp al, '='
jz fga_ignore
cmp al, '?'
jz fga_ignore
dec si ; let f_get_param fetch al again
jmp short f_get_param
fga_ignore:
next_is f_get_param
;----- f_get_param ---------------------------------------------------
; Last char was one of the four characters "]?=;".
; We are getting the first digit of a parameter, a quoted string,
; a ;, or a command.
f_get_param:
lodsb
cmp al, '0'
jb fgp_may_quote
cmp al, '9'
ja fgp_may_quote
; It's the first digit. Initialize current parameter with it.
sub al, '0'
mov byte ptr cs:[bx], al
mov cs:in_num, 1 ; set flag for sensing at cmd exec
next_is f_in_param
fgp_may_quote:
cmp al, '"'
jz fgp_isquote
cmp al, "'"
jnz fgp_semi_or_cmd ; jump to code shared with f_in_param
fgp_isquote:
mov cs:string_term, al ; save it for end of string
next_is f_get_string ; and read string into param_buffer
;----- f_get_string -------------------------------------
; Last character was a quote or a string element.
; Get characters until ending quote found.
f_get_string:
lodsb
cmp al, cs:string_term
jz fgs_init_next_param
mov byte ptr cs:[bx], al
cmp bx, cs:param_end
adc bx, 0 ; if bx<param_end bx++;
next_is f_get_string
; Ending quote was found.
fgs_init_next_param:
mov byte ptr cs:[bx], 0 ; initialize new parameter
; | Eat following semicolon, if any.
next_is f_eat_semi
;----- f_eat_semi -------------------------------------
; Last character was an ending quote.
; If this char is a semi, eat it; else unget it.
; Next state is always f_get_param.
f_eat_semi:
lodsb
cmp al, ';'
jz fes_eaten
inc cx
dec si
fes_eaten:
next_is f_get_param
;----- syntax_error ---------------------------------------
; A character was rejected by the state machine. Exit to
; main loop, and print offending character. Let main loop
; decrement CX (length of input string).
syntax_error:
mov cs:escvector, 0
mov ah, cs:cur_attrib
mov bx, cs:xlate_tab_ptr
jmp f_not_ANSI ; exit, print offending char
;------ f_in_param -------------------------------------
; Last character was a digit.
; Looking for more digits, a semicolon, or a command character.
f_in_param:
lodsb
cmp al, '0'
jb fgp_semi_or_cmd
cmp al, '9'
ja fgp_semi_or_cmd
; It's another digit. Add into current parameter.
sub al, '0'
xchg byte ptr cs:[bx], al
push dx
mov dl, 10
mul dl
pop dx
add byte ptr cs:[bx], al
next_is f_in_param
; Code common to states get_param and in_param.
; Accepts a semicolon or a command letter.
fgp_semi_or_cmd:
cmp al, ';'
jnz fgp_not_semi
cmp bx, cs:param_end ; prepare for next param-
adc bx, 0 ; if bp<param_end bp++;
; Set new param to zero, enter state f_get_param.
mov cs:in_num, 0 ; no longer inside number
jmp fgs_init_next_param ; spaghetti code attack!
fgp_not_semi:
; It must be a command letter.
cmp al, '@'
jb syntax_error
cmp al, 'z'
ja syntax_error
cmp al, 'Z'
jbe fgp_is_cmd
cmp al, 'a'
jb syntax_error
; It's a lower-case command letter.
; Remove hole between Z and a to save space in table.
sub al, 'a'-'['
fgp_is_cmd:
; It's a command letter. Save registers, convert letter
; into address of routine, set up new register usage, call routine.
push si ; These three registers hold info
push cx ; having to do with the input string,
push ds ; which has no interest at all to the
; control routine.
push cs
pop ds ; ds is now cs
sub al, '@' ; first command is @: insert chars
cbw
add ax, ax
add ax, offset ansi_fn_table
; ax is now pointer to command routine address in table
mov cx, bx
mov si, param_buffer ; si is now pointer to parameters
sub cx, si ;
test in_num, 1
jz fip_out_num
inc cx
fip_out_num: ; cx is now # of parameters
xchg ax, bx ; save pointer to routine in bx
; Calculate cur_x from DX.
mov al, max_x
inc ax
sub al, dl
mov cur_x, al
; Get first parameter into AX; if defaulted, set it to 1.
mov ah, 0
lodsb
or al, al
jnz fgp_callem
inc ax
fgp_callem:
; Finally, call the command subroutine.
call word ptr [bx]
pop ds
pop cx
pop si
mov ah, cs:cur_attrib ; Prepare for STOSW.
mov bx, cs:xlate_tab_ptr ; Prepare for translation.
mov cs:escvector, 0 ; No longer parsing escape sequence.
; Set flags for reentry at loopnz
or dx, dx ; "Any columns left on line?"
; Re-enter at bottom of main loop.
jmp f_ansi_exit
code ends
end ; of nansi_p.asm
page 66, 132
;------ nansi_i.asm ----------------------------------------------
; Contains code only needed at initialization time.
; (C) 1986 Daniel Kegel
; May be distributed for educational and personal use only
;-----------------------------------------------------------------
include nansi_d.asm ; definitions
; to nansi.asm
public dosfn0
; from nansi.asm
extrn break_handler:near
extrn int_29:near
if takeBIOS
extrn new_vid_bios:near
extrn old_vid_bios:dword
endif
extrn req_ptr:dword
extrn xlate_tab_ptr:word
; from nansi_p.asm
extrn param_buffer:word ; adr of first byte free for params
extrn param_end:word ; adr of last byte used for params
extrn redef_end:word ; adr of last used byte for redefs
code segment byte public 'CODE'
assume cs:code, ds:code
;-------- dos function # 0 : init driver ---------------------
; Initializes device driver interrupts and buffers, then
; passes ending address of the device driver to DOS.
; Since this code is only used once, the buffer can be set up on top
; of it to save RAM.
dosfn0 proc near
; Install BIOS keyboard break handler.
xor ax, ax
mov ds, ax
mov bx, 6Ch
mov word ptr [BX],offset break_handler
mov [BX+02], cs
; Install INT 29 quick putchar.
mov bx, 0a4h
mov word ptr [bx], offset int_29
mov [bx+2], cs
if takeBIOS
; Install INT 10h video bios replacement.
mov bx, 40h
mov ax, [bx]
mov word ptr cs:old_vid_bios, ax
mov ax, [bx+2]
mov word ptr cs:old_vid_bios[2], ax
mov word ptr [bx], offset new_vid_bios
mov word ptr [bx+2], cs
endif
push cs
pop ds
push cs
pop es ; es=cs so we can use stosb
cld ; make sure stosb increments di
; Calculate addresses of start and end of parameter/redef buffer.
; The buffer occupies the same area of memory as this code!
; ANSI parameters are accumulated at the lower end, and
; keyboard redefinitions are stored at the upper end; the variable
; param_end is the last byte used by params (changes as redefs added);
; redef_end is the last word used by redefinitions.
mov di, offset dosfn0
mov param_buffer, di
add di, 512
mov param_end, di ; addr of last byte in free area
inc di
; Build the default redefinition table:
; control-printscreen -> control-P
; (Must be careful not to write over ourselves here!)
mov al, 16 ; control P
stosb
mov ax, 7200h ; control-printscreen
stosw
mov ax, 1 ; length field
mov redef_end, di ; address of last used word in table
stosw
; Build a 1:1 output character translation table.
; It is 256 bytes long, starts just after the param/redef buffer,
; and is the last thing in the initialized device driver.
mov xlate_tab_ptr, di
xor ax, ax
init_loop:
stosb
inc al
jnz init_loop
xor ax, ax
; Return ending address of this device driver.
; Status is in AX.
lds si, req_ptr
mov word ptr [si+0Eh], di
mov [si+10h], cs
; Return exit status in ax.
ret
dosfn0 endp
code ends
end ; of nansi_i.asm
--
Name: David P. Zimmerman Nickname: "Davidann" (don't ask)
Cute quote: " (well, *I* think it's cute!)
Arpa: dzimmerman at blue.rutgers.edu
Uucp: ...{harvard, allegra, seismo}!topaz!dpz
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