itty-bitty-vtty/vt100.esc.S
2022-01-29 10:43:09 -05:00

321 lines
4.6 KiB
ArmAsm

lst off
rel
xc
xc
use vt.equ
mx %11
ext recalc_cursor,recalc_cursor_x,recalc_cursor_y
ext scroll_up,scroll_down
ext reset
ext update_sgr
vt100_esc ent
* #[()=>cH78DEM
* based on testing, unspecified chars in the 0x20-0x2f range cause it
* to gobble chars until 0x30- terminator (which ends the sequence but
* does not take an action)
* esc 1 -> hangs? [undocumented]
ldx #st_vt100
stx state
cmp #:MIN
blt :bad
cmp #:MAX+1
bge :rts
sec
sbc #:MIN
asl
tax
jmp (:table,x)
:bad
ldx #st_vt100_esc_bad
stx state
:rts
rts
:MIN equ 35
:MAX equ 99
:table
dw :pound ; #
dw :bad ; $
dw :bad ; %
dw :bad ; &
dw :bad ; '
dw :lparen ; (
dw :rparen ; )
dw :bad ; *
dw :bad ; +
dw :bad ; ,
dw :bad ; -
dw :bad ; .
dw :bad ; /
dw :rts ; 0
dw :rts ; 1
dw :rts ; 2
dw :rts ; 3
dw :rts ; 4
dw :rts ; 5
dw :rts ; 6
dw esc_7 ; 7
dw esc_8 ; 8
dw :rts ; 9
dw :rts ; :
dw :rts ; ;
dw :rts ; <
dw esc_eq ; =
dw esc_gt ; >
dw :rts ; ?
dw :rts ; @
dw :rts ; A
dw :rts ; B
dw :rts ; C
dw esc_D ; D
dw esc_E ; E
dw :rts ; F
dw :rts ; G
dw esc_H ; H
dw :rts ; I
dw :rts ; J
dw :rts ; K
dw :rts ; L
dw esc_M ; M
dw :rts ; N
dw :rts ; O
dw :rts ; P
dw :rts ; Q
dw :rts ; R
dw :rts ; S
dw :rts ; T
dw :rts ; U
dw :rts ; V
dw :rts ; W
dw :rts ; X
dw :rts ; Y
dw :rts ; Z
dw :csi ; [
dw :rts ; \
dw :rts ; ]
dw :rts ; ^
dw :rts ; _
dw :rts ; `
dw :rts ; a
dw :rts ; b
dw esc_c ; c
:lparen
ldx #st_vt100_esc_lparen
stx state
rts
:rparen
ldx #st_vt100_esc_rparen
stx state
rts
:pound
ldx #st_vt100_esc_pound
stx state
rts
:csi
ldx #st_vt100_csi
stx state
rts
esc_7 ; save cursor position, graphic rendition, and character set.
* based on testing, DECOM is also saved/restored.
lda x
sta saved_x
lda y
sta saved_y
lda DECOM
sta saved_decom
lda SGR
sta saved_sgr
rts
esc_8 ; restore cursor position, graphic rendition, and character set.
lda saved_x
sta x
lda saved_y
sta y
lda saved_decom
sta DECOM
lda saved_sgr
sta SGR
jsr update_sgr
jmp recalc_cursor
esc_eq ; enter alternate keypad mode
lda #$80
sta DECKPAM
rts
esc_gt ; exit alternate keypad mode
stz DECKPAM
rts
esc_H ; set tab stop
ext set_tab
ldx x
bmi :rts
jmp set_tab
:rts rts
esc_E ; next line
* This sequence causes the active position to move to the first position
* on the next line downward. If the active position is at the bottom
* margin, a scroll up is performed.
stz x
jsr recalc_cursor_x
; drop through
esc_D ; index
* This sequence causes the active position to move downward one line
* without changing the column position. If the active position is at the
* bottom margin, a scroll up is performed.
lda y
cmp DECBM
beq :scroll
cmp #23
beq :rts
inc y
jmp recalc_cursor_y
:scroll jmp scroll_down
:rts rts
esc_M ; reverse index
* Move the active position to the same horizontal position on the
* preceding line. If the active position is at the top margin, a scroll
* down is performed.
lda y
cmp DECTM
beq :scroll
cmp #0
beq :rts
dec y
jmp recalc_cursor_y
:scroll jmp scroll_up
:rts rts
esc_c ; TODO - reset terminal.
jmp reset
vt100_esc_bad ent
cmp #'0'
blt :rts
ldx #st_vt100
stx state
:rts
rts
vt100_esc_pound ent
* esc # 3 - make line double height (top half)
* esc # 4 - make line double height (bottom half)
* esc # 5 - make line single width, single height
* esc # 6 - make line double width
* esc # 8 - screen alignment - fill screen with E (SGR not honored)
* based on testing, this also resets the scrolling region and homes
* the cursor.
* based on testing, 0+ are term characters, 0x20-0x2f puts it in
* esc_bad state
ldx #st_vt100
stx state
cmp #:MIN
blt :bad
cmp #:MAX+1
bge :rts
sec
sbc #:MIN
asl
tax
jmp (:table,x)
:bad ldx #st_vt100_esc_bad
stx state
:rts rts
:MIN equ 48
:MAX equ 57
:table
dw :rts ; 0
dw :rts ; 1
dw :rts ; 2
dw :rts ; 3
dw :rts ; 4
dw :rts ; 5
dw :rts ; 6
dw :rts ; 7
dw :e ; 8
dw :rts ; 9
:e
* TODO - does this reset DECOM?
ext fill_screen
stz x
stz y
stz DECTM
lda #23
sta DECBM
jsr recalc_cursor
lda #"E"
jmp fill_screen
vt100_esc_lparen ent
vt100_esc_rparen ent
* ( sets G0, ) sets G1
* A - UK set
* B - ASCII set
* 0 - Special Graphics
* 1 - Alternate Char ROM Standard Char Set
* 2 - Alternate Char ROM Special Graphics
* SO, aka Control-N aka 0x0e set the G1 char set
* SI, aka Control-O aka 0x0f set the G0 char set
* not currently supported.
* TODO - mouse text support?
ldx #st_vt100
stx state
cmp #'0'
blt :bad
rts
:bad ldx #st_vt100_esc_bad
stx state
:rts rts
sav vt100.esc.L