dos33fsprogs/tfv/tfv.s
2017-05-17 23:25:07 -04:00

529 lines
9.9 KiB
ArmAsm

.define EQU =
KEYPRESS EQU $C000
KEYRESET EQU $C010
;; SOFT SWITCHES
GR EQU $C050
TEXT EQU $C051
FULLGR EQU $C052
TEXTGR EQU $C053
PAGE0 EQU $C054
PAGE1 EQU $C055
LORES EQU $C056
HIRES EQU $C057
PADDLE_BUTTON0 EQU $C061
PADDL0 EQU $C064
PTRIG EQU $C070
;; MONITOR ROUTINES
HLINE EQU $F819 ;; HLINE Y,$2C at A
VLINE EQU $F828 ;; VLINE A,$2D at Y
CLRSCR EQU $F832 ;; Clear low-res screen
CLRTOP EQU $F836 ;; clear only top of low-res screen
SETCOL EQU $F864 ;; COLOR=A
BASCALC EQU $FBC1 ;;
HOME EQU $FC58 ;; Clear the text screen
WAIT EQU $FCA8 ;; delay 1/2(26+27A+5A^2) us
SETINV EQU $FE80 ;; INVERSE
SETNORM EQU $FE84 ;; NORMAL
COUT1 EQU $FDF0 ;; output A to screen
;; Zero page addresses
WNDLFT EQU $20
WNDWDTH EQU $21
WNDTOP EQU $22
WNDBTM EQU $23
CH EQU $24
CV EQU $25
GBASL EQU $26
GBASH EQU $27
BASL EQU $28
BASH EQU $29
H2 EQU $2C
V2 EQU $2D
MASK EQU $2E
COLOR EQU $30
FIRST EQU $F0
LASTKEY EQU $F1
PADDLE_STATUS EQU $F2
XPOS EQU $F3
YPOS EQU $F4
TEMP EQU $FA
RUN EQU $FA
TEMP2 EQU $FB
TEMPY EQU $FB
INL EQU $FC
INH EQU $FD
OUTL EQU $FE
OUTH EQU $FF
;=============================
; set low-res graphics, page 0
;=============================
jsr HOME
jsr set_gr_page0
;=================
; clear the screen
;=================
jsr CLRTOP
lda #$c
sta BASH
lda #$0
sta BASL ; load image off-screen 0xc00
lda #>(title_image)
sta GBASH
lda #<(title_image)
sta GBASL
jsr load_rle_gr
jsr gr_copy
lda #20
sta YPOS
lda #20
sta XPOS
main_loop:
jsr gr_copy
jsr put_sprite
jsr wait_until_keypressed
lda LASTKEY
cmp #('Q')
beq exit
cmp #('I')
bne check_down
dec YPOS
dec YPOS
check_down:
cmp #('M')
bne check_left
inc YPOS
inc YPOS
check_left:
cmp #('J')
bne check_right
dec XPOS
check_right:
cmp #('K')
bne check_done
inc XPOS
check_done:
jmp main_loop
exit:
lda #$4
sta BASH
lda #$0
sta BASL ; restore to 0x400 (page 0)
; copy to 0x400 (page 0)
; call home
jsr HOME
; Return to BASIC?
rts
;=====================================================================
;= ROUTINES
;=====================================================================
;=================
; load RLE image
;=================
; Output is BASH/BASL
; Input is in GBASH/GBASL
load_rle_gr:
lda #$0
tax
tay ; init X and Y to 0
sta CV ; ycoord=0
lda (GBASL),y ; load xsize
sta CH
iny ; (we should check if we had
; bad luck and overflows page)
rle_loop:
lda (GBASL),y ; load run value
cmp #$ff ; if 0xff
beq rle_done ; we are done
sta RUN
iny ; point to next value
bne rle_yskip1 ; if overflow, increment address
inc GBASH
rle_yskip1:
lda (GBASL),y ; load value to write
iny
bne rle_yskip2
inc GBASH
rle_yskip2:
sty TEMP2 ; save y for later
pha
lda #$0
tay
pla ; convoluted way to set y to 0
rle_run_loop:
sta (BASL),y ; write out the value
inc BASL ; increment the pointer
bne rle_skip3 ; if wrapped
inc BASH ; then increment the high value
rle_skip3:
inx ; increment the X value
cpx CH ; compare against the image width
bcc rle_not_eol ; if less then keep going
pha ; save out value on stack
lda BASL ; cheat to avoid a 16-bit add
cmp #$a7 ; we are adding 0x58 to get
bcc rle_add_skip ; to the next line
inc BASH
rle_add_skip:
clc
adc #$58 ; actually do the 0x58 add
sta BASL ; and store it back
inc CV ; add 2 to ypos
inc CV ; each "line" is two high
lda CV ; load value
cmp #15 ; if it's greater than 14 it wraps
bcc rle_no_wrap ; Thanks Woz
lda #$0 ; we wrapped, so set to zero
sta CV
; when wrapping have to sub 0x3d8
sec ; this is a 16-bit subtract routine
lda BASL
sbc #$d8 ; LSB
sta BASL
lda BASH ; MSB
sbc #$3 ;
sta BASH
rle_no_wrap:
lda #$0 ; set X value back to zero
tax
pla ; restore value to write from stack
rle_not_eol:
dec RUN ; decrement run value
bne rle_run_loop ; if not zero, keep looping
ldy TEMP2 ; restore the input pointer
sec
bcs rle_loop ; and branch always
rle_done:
lda #$15 ; move the cursor somewhere sane
sta CV
rts
;==========================================================
; set_text_page0
;==========================================================
;
set_text_page0:
bit PAGE0 ; set page0
bit TEXT ; set text mode
rts
;==========================================================
; set_gr_page0
;==========================================================
;
set_gr_page0:
;lda #4
;sta GR_PAGE
bit PAGE0 ; set page 0
bit LORES ; Lo-res graphics
bit TEXTGR ; mixed gr/text mode
bit GR ; set graphics
rts
;=========================================================
; gr_copy
;=========================================================
; for now copy 0xc00 to 0x400
; 2 + 8*38 + 4*80*23 + 4*120*26 + 13 = 20,159 = 20ms = 50Hz
;
gr_copy:
ldx #0 ; set y to zero ; 2
gr_copy_loop:
stx TEMP ; save y ; 3
txa ; move to A ; 2
asl ; mult by 2 ; 2
tay ; put into Y ; 2
lda gr_offsets,Y ; lookup low byte for line addr ; 5
sta OUTL ; out and in are the same ; 3
sta INL ; 3
lda gr_offsets+1,Y ; lookup high byte for line addr ; 5
sta OUTH ; 3
adc #$8 ; for now, fixed 0xc ; 2
sta INH ; 3
ldx TEMP ; restore y ; 3
ldy #0 ; set X counter to 0 ; 2
gr_copy_line:
lda (INL),Y ; load a byte ; 5
sta (OUTL),Y ; store a byte ; 6
iny ; increment pointer ; 2
cpx #$4 ; don't want to copy bottom 4*40 ; 2
bcs gr_copy_above4 ; 3
gr_copy_below4:
cpy #120 ; for early ones, copy 120 bytes ; 2
bne gr_copy_line ; 3
beq gr_copy_line_done ; 3
gr_copy_above4: ; for last four, just copy 80 bytes
cpy #80 ; 2
bne gr_copy_line ; 3
gr_copy_line_done:
inx ; increment y value ; 2
cpx #8 ; there are 8 of them ; 2
bne gr_copy_loop ; if not, loop ; 3
rts ; 6
;==========================================================
; Wait until keypressed
;==========================================================
;
wait_until_keypressed:
lda KEYPRESS ; check if keypressed
bpl wait_until_keypressed ; if not, loop
jmp figure_out_key
;==========================================================
; Get Key
;==========================================================
;
get_key:
check_paddle_button:
; check for paddle button
bit PADDLE_BUTTON0
bpl no_button
lda #' '+128
jmp save_key
no_button:
lda KEYPRESS
bpl no_key
figure_out_key:
cmp #' '+128 ; the mask destroys space
beq save_key ; so handle it specially
and #$5f ; mask, to make upper-case
check_right_arrow:
cmp #$15
bne check_left_arrow
lda #'K'
check_left_arrow:
cmp #$08
bne check_up_arrow
lda #'J'
check_up_arrow:
cmp #$0B
bne check_down_arrow
lda #'I'
check_down_arrow:
cmp #$0A
bne check_escape
lda #'M'
check_escape:
cmp #$1B
bne save_key
lda #'Q'
jmp save_key
no_key:
bit PADDLE_STATUS
bpl no_key_store
; check for paddle action
; code from http://web.pdx.edu/~heiss/technotes/aiie/tn.aiie.06.html
inc PADDLE_STATUS
lda PADDLE_STATUS
and #$03
beq check_paddles
jmp no_key_store
check_paddles:
lda PADDLE_STATUS
and #$80
sta PADDLE_STATUS
ldx #$0
LDA PTRIG ;TRIGGER PADDLES
LDY #0 ;INIT COUNTER
NOP ;COMPENSATE FOR 1ST COUNT
NOP
PREAD2: LDA PADDL0,X ;COUNT EVERY 11 uSEC.
BPL RTS2D ;BRANCH WHEN TIMED OUT
INY ;INCREMENT COUNTER
BNE PREAD2 ;CONTINUE COUNTING
DEY ;COUNTER OVERFLOWED
RTS2D: ;RETURN W/VALUE 0-255
cpy #96
bmi paddle_left
cpy #160
bmi no_key_store
lda #'K'
jmp save_key
paddle_left:
lda #'J'
jmp save_key
no_key_store:
lda #0 ; no key, so save a zero
save_key:
sta LASTKEY ; save the key to our buffer
bit KEYRESET ; clear the keyboard buffer
rts
;=============================================
; put_sprite
;=============================================
put_sprite:
lda #>tb1_sprite ; hardcoded for tb1 for now
sta INH
lda #<tb1_sprite
sta INL
ldy #0 ; byte 0 is xsize
lda (INL),Y
sta CH
iny
lda (INL),Y ; byte 1 is ysize
sta CV
iny
lda YPOS ; make a copy of ypos
sta TEMPY ; as we modify it
put_sprite_loop:
sty TEMP ; save sprite pointer
ldy TEMPY
lda gr_offsets,Y ; lookup low-res memory address ; 5
clc
adc XPOS ; add in xpos
sta OUTL ; store out low byte of addy ; 3
lda gr_offsets+1,Y ; look up high byte ; 5
sta OUTH ; and store it out ; 3
ldy TEMP ; restore sprite pointer ; 3
ldx CH
put_sprite_pixel:
lda (INL),Y ; get sprite colors
iny ; increment sprite pointer
sty TEMP ; save sprite pointer
ldy #$0
cmp #$0 ; if all zero, transparent
beq put_sprite_done_draw ; don't draw it
; FIXME: use BIT?
sta COLOR ; save color for later
and #$f0 ; check if top nibble zero
bne put_sprite_bottom ; if not skip ahead
lda #$0f ; setup mask
sta MASK
bmi put_sprite_mask
put_sprite_bottom:
lda COLOR ; re-load color
and #$0f ; check if bottom nibble zero
bne put_sprite_all ; if not, skip ahead
lda #$0f
sta MASK ; setup mask
put_sprite_mask:
lda (OUTL),Y ; get color at output
and MASK ; mask off unneeded part
ora COLOR ; or the color in
sta (OUTL),Y ; store it back
jmp put_sprite_done_draw ; we are done
put_sprite_all:
lda COLOR ; load color
sta (OUTL),Y ; and write it out
put_sprite_done_draw:
ldy TEMP ; restore sprite pointer
inc OUTL ; increment output pointer
dex ; decrement x counter
bne put_sprite_pixel ; if not done, keep looping
inc TEMPY ; each line has two y vars
inc TEMPY
dec CV ; decemenet total y count
bne put_sprite_loop ; loop if not done
rts ; return
; waste memory with a lookup table
; maybe faster than using GBASCALC?
gr_offsets:
.word $400,$480,$500,$580,$600,$680,$700,$780
.word $428,$4a8,$528,$5a8,$628,$6a8,$728,$7a8
.word $450,$4d0,$550,$5d0,$650,$6d0,$750,$7d0
tb1_sprite:
.byte $8,$4
.byte $55,$50,$00,$00,$00,$00,$00,$00
.byte $55,$55,$55,$00,$00,$00,$00,$00
.byte $ff,$1f,$4f,$2f,$ff,$22,$20,$00
.byte $5f,$5f,$5f,$5f,$ff,$f2,$f2,$f2
.include "title.inc"