+++ /dev/null
-;
-; zx128 vt primitives
-;
-
- .module zxvideo
-
- ; exported symbols
- .globl _plot_char
- .globl _scroll_down
- .globl _scroll_up
- .globl _cursor_on
- .globl _cursor_off
- .globl _cursor_disable
- .globl _clear_lines
- .globl _clear_across
- .globl _do_beep
- .globl _fontdata_8x8
- .globl _curattr
- .globl _vtattr
- .globl map_kernel
- .globl map_video
-
- ; Build the video library as the only driver
-
-ZXVID_ONLY .equ 1
-
- .area _VIDEO
-
-;
-; zx128 vt primitives hacked a bit
-;
-; Will be replaced by Timex video shortly
-;
- ; exported symbols
- .globl zx_plot_char
- .globl zx_scroll_down
- .globl zx_scroll_up
- .globl zx_cursor_on
- .globl zx_cursor_off
- .globl zx_cursor_disable
- .globl zx_clear_lines
- .globl zx_clear_across
- .globl zx_do_beep
- .globl _fontdata_8x8
- .globl _curattr
- .globl _vtattr
-
-videopos:
- ld a,e
- and #7
- rrca
- rrca
- rrca
- add a,d
- ld d,e
- ld e,a
- ld a,d
- and #0x18
- or #0x40 ; Standard screen
- ld d,a
- jp map_video
-
-videoattr:
- ; 32 x E + D into HL
- ld a,e
- rrca
- rrca
- rrca ; A is now 32xE with the top bits overflowed
- ; into the low 2 bits
- ld l,a
- and #3 ; Extract the low 2 bits for the high
- add #0x58 ; Attributes start 0x5800
- ld h,a
- ld a,l
- and #0xE0 ; mask the bits that are valid
- add d ; add the low 5 bits from D
- ld l,a ; and done (the add can't overflow)
- ret
-
- .if ZXVID_ONLY
-_plot_char:
- .endif
-zx_plot_char:
- pop hl
- pop de ; D = x E = y
- pop bc
- push bc
- push de
- push hl
-
- ld hl,(_vtattr) ; l is vt attributes
- push de
- push hl ; save attributes as inaccessible once vid mapped
-
- call videopos
-
- ld b, #0 ; calculating offset in font table
- ld a, c
- or a ; clear carry
- rla
- rl b
- rla
- rl b
- rla
- rl b
- ld c, a
-
- ld hl, #_fontdata_8x8-32*8 ; font
- add hl, bc ; hl points to first byte of char data
-
- pop bc
- ; We do underline for now - not clear italic or bold are useful
- ; with the font we have.
-
- ; printing
-plot_char_loop:
- ld a, (hl)
- ld (de), a
- inc hl ; next byte of char data
- inc d ; next screen line
-
- ld a, (hl)
- ld (de), a
- inc hl ; next byte of char data
- inc d ; next screen line
-
- ld a, (hl)
- ld (de), a
- inc hl ; next byte of char data
- inc d ; next screen line
-
- ld a, (hl)
- ld (de), a
- inc hl ; next byte of char data
- inc d ; next screen line
-
- ld a, (hl)
- ld (de), a
- inc hl ; next byte of char data
- inc d ; next screen line
-
- ld a, (hl)
- ld (de), a
- inc hl ; next byte of char data
- inc d ; next screen line
-
- ld a, (hl)
- ld (de), a
- inc hl ; next byte of char data
- inc d ; next screen line
-
- ld a, (hl)
- bit 1,c ; underline ?
- jr nz, last_ul
-plot_attr:
- ld (de), a
-
- pop de
- call videoattr
- ld a,(_curattr)
- ld (hl),a
- jp map_kernel
-
-last_ul:
- ld a,#0xff
- jr plot_attr
-
- .if ZXVID_ONLY
-_clear_lines:
- .endif
-zx_clear_lines:
- pop hl
- pop de ; E = line, D = count
- push de
- push hl
- ; This way we handle 0 correctly
- inc d
- jr nextline
-
-clear_next_line:
- push de
- ld d, #0 ; from the column #0
- ld b, d ; b = 0
- ld c, #32 ; clear 32 cols
- push bc
- push de
- call _clear_across
- pop hl ; clear stack
- pop hl
-
- pop de
- inc e
-nextline:
- dec d
- jr nz, clear_next_line
-
- ret
-
-
- .if ZXVID_ONLY
-_clear_across:
- .endif
-zx_clear_across:
- pop hl
- pop de ; DE = coords
- pop bc ; C = count
- push bc
- push de
- push hl
- ld a,c
- or a
- ret z ; No work to do - bail out
- push de
- push bc
- call videopos ; first pixel line of first character in DE
- push de
- pop hl ; copy to hl
- xor a
-
- ; no boundary checks. Assuming that D + C < SCREEN_WIDTH
-
-clear_line:
- ld b, #8 ; 8 pixel lines to clear for this char
-clear_char:
- ld (de), a
- inc d
- djnz clear_char
-
- ex de, hl
- inc de
- push de
- pop hl
-
- dec c
- jr nz, clear_line
- pop bc
- pop de
- call videoattr
- ld a,(_curattr)
- ld b,c
-setattr:
- ld (hl),a
- inc hl
- djnz setattr
- jp map_kernel
-
-copy_line:
- ; HL - source, DE - destination
-
- ; convert line coordinates to screen coordinates both for DE and HL
- push de
- ex de, hl
- call videopos
- ex de, hl
- pop de
- call videopos
-
- ld c, #8
-
-copy_line_nextchar:
- push hl
- push de
-
- ld b, #32
-
-copy_pixel_line:
- ld a, (hl)
- ld (de), a
- inc e
- inc l
- djnz copy_pixel_line
-
- pop de
- pop hl
- inc d
- inc h
- dec c
- jr nz, copy_line_nextchar
- ret
-
- ; TODO: the LDIR way should be much faster
-
- .if ZXVID_ONLY
-_scroll_down:
- .endif
-zx_scroll_down:
- ; set HL = (0,22), DE = (0, 23)
- xor a
- ld d, a
- ld h, a
- ld l, #22
- ld e, #23
- ld c, #23 ; 23 lines to move
-
- call map_video
-
-loop_scroll_down:
- push hl
- push de
- push bc
-
- call copy_line
-
- pop bc
- pop de
- pop hl
-
- dec l
- dec e
- dec c
- jr nz, loop_scroll_down
-
- ; Attributes
- ld hl,#0x5ADF
- ld de,#0x5AFF
- ld bc,#0x02E0
- lddr
-
- jp map_kernel
-
-
- .if ZXVID_ONLY
-_scroll_up:
- .endif
-zx_scroll_up:
- ; set HL = (0,1), DE = (0, 0)
- xor a
- ld d, a
- ld e, a
- ld h, a
- ld l, #1
- ld c, #23 ; 23 lines to move
-
- call map_video
-
-loop_scroll_up:
- push hl
- push de
- push bc
-
- call copy_line
-
- pop bc
- pop de
- pop hl
-
- inc l
- inc e
- dec c
- jr nz, loop_scroll_up
-
- ld hl,#0x5820
- ld de,#0x5800
- ld bc,#0x02E0
- ldir
- jp map_kernel
-
- .if ZXVID_ONLY
-_cursor_on:
- .endif
-zx_cursor_on:
- pop hl
- pop de
- push de
- push hl
- ld (cursorpos), de
-
- call videopos
- ld a, #7
- add a, d
- ld d, a
- ld a, #0xFF
- ld (de), a
- jp map_kernel
- .if ZXVID_ONLY
-_cursor_disable:
-_cursor_off:
- .endif
-zx_cursor_disable:
-zx_cursor_off:
- ld de, (cursorpos)
- call videopos
- ld a, #7
- add a, d
- ld d, a
- xor a
- ld (de), a
- jp map_kernel
-
- .if ZXVID_ONLY
-_do_beep:
- .endif
-zx_do_beep:
- ret
-
- .area _DATA
-
-cursorpos:
- .dw 0
-
- .area _COMMONDATA
-
-_curattr:
- .db 7
-
public / FUZIX.git / commitdiff