Difference between revisions of "Light pen driver"
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| Line 46: | Line 46: | ||
add hl,de | add hl,de | ||
l9cbd: | l9cbd: | ||
| − | ld ( | + | ld (data_0a410h),hl ;; detected 'position' or 'ffff' for not detected |
pop bc | pop bc | ||
ld a,082h | ld a,082h | ||
| Line 119: | Line 119: | ||
ld hl,0018fh | ld hl,0018fh | ||
sbc hl,de | sbc hl,de | ||
| − | ld ( | + | ld (data_0a410),hl |
ret | ret | ||
| − | + | sub_9ce4h: | |
ld a,000h | ld a,000h | ||
ld bc,01a1ah | ld bc,01a1ah | ||
| Line 172: | Line 172: | ||
sub_9d35h: | sub_9d35h: | ||
| − | ld bc,( | + | ld bc,(data_0a418) |
l9d79h: | l9d79h: | ||
push bc | push bc | ||
| Line 178: | Line 178: | ||
ld hl,00014h | ld hl,00014h | ||
call 0bbf9h ;; gra line relative | call 0bbf9h ;; gra line relative | ||
| − | ld de,( | + | ld de,(data_0a416) |
ld hl,0ffech | ld hl,0ffech | ||
call 0bbc3h ;; gra move relative | call 0bbc3h ;; gra move relative | ||
| Line 197: | Line 197: | ||
ld hl,00000h | ld hl,00000h | ||
call 0bbc3h ;; gra move relative | call 0bbc3h ;; gra move relative | ||
| − | ld bc,( | + | ld bc,(data_0a420) |
l9db4h: | l9db4h: | ||
push bc | push bc | ||
| Line 207: | Line 207: | ||
ld hl,00014h | ld hl,00014h | ||
call 0bbf9h ;; gra line relative | call 0bbf9h ;; gra line relative | ||
| − | ld de,( | + | ld de,(data_0a416) |
ld hl,0ffech ;; -20 | ld hl,0ffech ;; -20 | ||
call 0bbc3h ;; gra move relative | call 0bbc3h ;; gra move relative | ||
| Line 213: | Line 213: | ||
djnz l9db4h | djnz l9db4h | ||
ld hl,0ffffh | ld hl,0ffffh | ||
| − | ld ( | + | ld (data_0a410),hl |
ret | ret | ||
sub_9d9ah: | sub_9d9ah: | ||
pop bc | pop bc | ||
| − | ld ( | + | ld (data_0a410),hl |
call 0bbc6h ;; gra ask cursor | call 0bbc6h ;; gra ask cursor | ||
| − | ld ( | + | ld (data_0a412),de |
ret | ret | ||
| Line 245: | Line 245: | ||
push de | push de | ||
call sub_09e08h | call sub_09e08h | ||
| − | ld ( | + | ld (data_0a414),hl |
ld de,05398h | ld de,05398h | ||
ld b,004h | ld b,004h | ||
l9e0bh: | l9e0bh: | ||
push bc | push bc | ||
| − | ld hl,( | + | ld hl,(data_0a414) |
ld c,b | ld c,b | ||
ld b,000h | ld b,000h | ||
| Line 276: | Line 276: | ||
l9e2dh: | l9e2dh: | ||
push bc | push bc | ||
| − | ld hl,( | + | ld hl,(data_0a414) |
ld c,b | ld c,b | ||
ld b,000h | ld b,000h | ||
| Line 302: | Line 302: | ||
push hl | push hl | ||
ex de,hl | ex de,hl | ||
| − | ld de,( | + | ld de,(data_0a416) |
call sub_9c94h ;; HL = HL/DE | call sub_9c94h ;; HL = HL/DE | ||
ex de,hl | ex de,hl | ||
| Line 311: | Line 311: | ||
sub_9e1fh: | sub_9e1fh: | ||
call sub_9c8ah | call sub_9c8ah | ||
| − | ld hl,( | + | ld hl,(data_0a418) |
| − | ld ( | + | ld (data_0a420h),hl |
| − | ld hl,( | + | ld hl,(data_0a410) |
ld a,0ffh | ld a,0ffh | ||
cp h | cp h | ||
ret z | ret z | ||
| − | ld ( | + | ld (data_a41c),hl |
| − | ld de,( | + | ld de,(data_0a412) |
| − | ld ( | + | ld (data_a41a),de |
l9e7ah: | l9e7ah: | ||
ld de,0000ah | ld de,0000ah | ||
| Line 328: | Line 328: | ||
l9e85h: | l9e85h: | ||
push hl | push hl | ||
| − | ld hl,( | + | ld hl,(data_a412) |
add hl,de | add hl,de | ||
ex de,hl | ex de,hl | ||
| Line 337: | Line 337: | ||
call sub_09ed2h | call sub_09ed2h | ||
call sub_09de6h | call sub_09de6h | ||
| − | ld hl,( | + | ld hl,(data_a410) |
ld a,0ffh | ld a,0ffh | ||
cp h | cp h | ||
| Line 351: | Line 351: | ||
call 0bb1eh ;; km test key | call 0bb1eh ;; km test key | ||
ret z | ret z | ||
| − | ld hl,( | + | ld hl,(data_a41c) |
| − | ld de,( | + | ld de,(data_a41a) |
call 0bbc0h ;; gra move absolute | call 0bbc0h ;; gra move absolute | ||
| − | ld hl,( | + | ld hl,(data_a410) |
| − | ld de,( | + | ld de,(data_a412) |
| − | ld a,( | + | ld a,(data_a41e) |
call 0bbdeh ;; gra set pen | call 0bbdeh ;; gra set pen | ||
| − | ld ( | + | ld (data_a41c),hl |
| − | ld ( | + | ld (data_a41a),de |
call 0bbf6h ;; gra line absolute | call 0bbf6h ;; gra line absolute | ||
ld hl,(0a410h) | ld hl,(0a410h) | ||
| Line 381: | Line 381: | ||
sub_9eb7h: | sub_9eb7h: | ||
| − | ld hl,( | + | ld hl,(data_a41a) |
| − | ld de,( | + | ld de,(data_a412) |
and a | and a | ||
sbc hl,de | sbc hl,de | ||
| Line 403: | Line 403: | ||
ld hl,00000h | ld hl,00000h | ||
call 0bbc3h ;; gra move relative | call 0bbc3h ;; gra move relative | ||
| − | ld bc,( | + | ld bc,(data_a420) |
push bc | push bc | ||
ld de,00000h | ld de,00000h | ||
| Line 413: | Line 413: | ||
jp nz,sub_9efeh | jp nz,sub_9efeh | ||
sub_9ef5h: | sub_9ef5h: | ||
| − | ld hl,( | + | ld hl,(data_a422) |
| − | ld ( | + | ld (data_a410),hl |
jp sub_9d9ah | jp sub_9d9ah | ||
sub_9efeh: | sub_9efeh: | ||
| − | ld ( | + | ld (data_a422),hl |
| − | ld de,( | + | ld de,(data_a416) |
ld hl,0ffech | ld hl,0ffech | ||
call 0bbc3h ;; gra move relative | call 0bbc3h ;; gra move relative | ||
| Line 425: | Line 425: | ||
djnz l9f22h | djnz l9f22h | ||
ld hl,0ffffh | ld hl,0ffffh | ||
| − | ld ( | + | ld (data_a410),hl |
ret | ret | ||
sub_9f82h: | sub_9f82h: | ||
call sub_9e98h | call sub_9e98h | ||
| − | ld bc,( | + | ld bc,(data_a420) |
l9f5ch: | l9f5ch: | ||
push bc | push bc | ||
| Line 441: | Line 441: | ||
jp z,sub_9ef5h | jp z,sub_9ef5h | ||
| − | ld ( | + | ld (data_0a422),hl |
| − | ld de,( | + | ld de,(data_a416) |
ld hl,00000h | ld hl,00000h | ||
and a | and a | ||
| Line 467: | Line 467: | ||
;; screen dump to printer. | ;; screen dump to printer. | ||
sub_0a028h: | sub_0a028h: | ||
| − | ld a,013h | + | ld a,013h ;; INC instruction |
| − | ld ( | + | ld (la124),a |
ld a,00eh | ld a,00eh | ||
| − | ld ( | + | ld (la0e1+1),a |
| − | ld a,( | + | ld a,(data_a133) |
bit 1,a | bit 1,a | ||
jr z,la083h | jr z,la083h | ||
| − | ld a,000h | + | ld a,000h ;; NOP instruction |
| − | ld ( | + | ld (la124),a |
ld a,007h | ld a,007h | ||
| − | ld ( | + | ld (la0e1+1),a |
la083h: | la083h: | ||
call 0bd28h ;; mc reset printer | call 0bd28h ;; mc reset printer | ||
| Line 516: | Line 516: | ||
ld a,000h ;; number of columns low byte | ld a,000h ;; number of columns low byte | ||
call 0bd2bh ;; mc print char | call 0bd2bh ;; mc print char | ||
| − | ld a,( | + | ld a,(data_a133) |
bit 0,a | bit 0,a | ||
jr z,la0b4h | jr z,la0b4h | ||
| Line 549: | Line 549: | ||
ret nz | ret nz | ||
ld hl,(data_a12d) | ld hl,(data_a12d) | ||
| + | la0e1: | ||
ld de,0000eh | ld de,0000eh | ||
add hl,de | add hl,de | ||
| Line 595: | Line 596: | ||
call sub_a115h ;; get current X/Y graphics position | call sub_a115h ;; get current X/Y graphics position | ||
inc de ;; increment X to next pixel accross screen. | inc de ;; increment X to next pixel accross screen. | ||
| + | la124: | ||
inc de | inc de | ||
call sub_a10dh ;; set current X/Y graphics position | call sub_a10dh ;; set current X/Y graphics position | ||
| Line 606: | Line 608: | ||
db 00h,00h | db 00h,00h | ||
data_a131: | data_a131: | ||
| − | db | + | dw 000eh |
| − | db 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0 | + | data_a133: |
| + | db 00h | ||
| + | data_a134: | ||
| + | db 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0 | ||
sub_a154h: | sub_a154h: | ||
| Line 754: | Line 759: | ||
defw 0bch | defw 0bch | ||
| + | |||
| + | ;; detected light pen position | ||
| + | data_a410: | ||
| + | defw 0 | ||
| + | data_a412: | ||
| + | defw 0 | ||
| + | ;; memory/buffer address | ||
| + | data_a414: | ||
| + | defw 0 | ||
| + | data_a416: | ||
| + | defw 0 | ||
| + | data_a418: | ||
| + | defw 0 | ||
| + | |||
| + | ;; gra x,y position | ||
| + | data_a41a: | ||
| + | defw 0 | ||
| + | data_a41c: | ||
| + | defw 0 | ||
| + | ;; graphics pen | ||
| + | data_a41e: | ||
| + | defb 0 | ||
| + | defb 0 | ||
| + | data_a420: | ||
| + | defw 0 | ||
end | end | ||
</pre> | </pre> | ||
[[Category:Source code]] | [[Category:Source code]] | ||
Latest revision as of 03:30, 21 August 2025
;; Dissassembled and commented from MCPEN.BIN
org 09c40h
sub_9c40h:
call 0bd19h ;; mc wait flyback
di
ld bc,0f40eh ;; we want to select AY register 14
out (c),c
ld b,0f6h
in a,(c)
and 030h
ld c,a
or 0c0h ;; AY control select register.
out (c),a
out (c),a ;; BUG. Should be out (c),c to be compatible with Plus.
inc b
ld a,092h
out (c),a
push bc
ld bc,0f649h ;; AY control read from register and select keyboard line 9 (joystick)
out (c),c
out (c),c ;; BUG? No need to do this twice.
ld b,0f4h
;; loop reading joystick until input seen or timeout
ld hl,0fa66h ;; timeout is 0-FA66 because it counts up from this starting point.
;; timeout is 59A loops.
l9c68:
in a,(c)
cp 0fdh ;; 11111101. Bits are '1' if 'no press', but '0' if pressed. checking joy 0 down.
jr z,l9c79
inc l
jr nz,l9c68
inc h
jr nz,l9c68
;; timeout. not detected
ld hl,0ffffh
jr l9cbdh
l9c79:
;; detected.
ld de,00420h
add hl,de
l9cbd:
ld (data_0a410h),hl ;; detected 'position' or 'ffff' for not detected
pop bc
ld a,082h
out (c),a
dec b
out (c),c ;; Set AY control inactive.
ei
ret
sub_9c8ah:
call sub_9da6h ;; screen to buffer
call sub_9ce4h
call sub_9db2h ;; buffer to screen
ret
;; HL = HL/DE
sub_9c94:
ld a,h
ld c,l
ld b,010h ;; 16 bits.
ld hl,00000h
l9cdbh:
rl c
rla
adc hl,hl
sbc hl,de
jr nc,l9ce5h
add hl,de
l9ce5h:
ccf
djnz l9cdbh
rl c
rla
ld h,a
ld l,c
ret
;; HL = HL * DE
sub_9caeh:
ld a,l
ld c,h
ld b,010h ;; 16 bits
ld hl,00000h
l9cf5h:
srl c
rra
jr nc,l9cfbh
add hl,de
l9cfbh:
ex de,hl
add hl,hl
ex de,hl
djnz l9cf5h
ret
sub_9cc1h:
call sub_9c40h ;; detect
ld a,0ffh
cp h
ret z
;; detected.
ld de,00002h
call sub_9c94h ;; HL = HL/DE
ld de,00064h
call sub_9caeh ;; HL = HL*DE
ld de,00084h
call sub_9c94h ;; HL = HL/DE
ex de,hl
ld hl,0018fh
sbc hl,de
ld (data_0a410),hl
ret
sub_9ce4h:
ld a,000h
ld bc,01a1ah
call 0bc32h ;; scr set ink
call 0bc14h ;; scr clear
ld a,001h
call 0bbdeh ;; gra set pen
call sub_9cc1h ;; get position
ld a,0ffh
cp h
ret z
ld de,0000ah
and a
sbc hl,de
;; BUG? This is jumping just after 0x021 of LD HL and then executing two nops before LD DE,0000h
;;jr nc,$+2
jr nc,l9d06
ld hl,00000h
l9d06:
ld de,00000h
call 0bbc0h ;; gra move absolute
ld a,001h
ld bc,01a1ah
call 0bc32h ;; scr set ink
ld a,000h
ld bc,00000h
call 0bc32h ;; scr set ink
ld b,00ah
l9d1e:
call 0bd19h ;; mc wait flyback
;; BUG? this is jumping back to the 0x0a in LD B,0ah
;; djnz $-4
djnz l9d1e
ld b,020h ;; number of lines
l9d65h:
push bc
call sub_9d35h ;; draw lines
call sub_9c40h ;;detect
pop bc
ld a,0ffh
cp h
jr nz,l9d91h
djnz l9d65h
ret
sub_9d35h:
ld bc,(data_0a418)
l9d79h:
push bc
ld de,00000h
ld hl,00014h
call 0bbf9h ;; gra line relative
ld de,(data_0a416)
ld hl,0ffech
call 0bbc3h ;; gra move relative
pop bc
djnz l9d79h
ret
l9d91h:
ld de,0ffech ;; -20
ld hl,00000h
call 0bbc3h ;; gra move relative
l9d9ah:
ld a,000h
call 0bbdeh ;; gra set pen
call sub_09d35h ;; lines
ld a,001h
call 0bbdeh ;; gra set pen
ld de,0ffech ;; -20
ld hl,00000h
call 0bbc3h ;; gra move relative
ld bc,(data_0a420)
l9db4h:
push bc
call sub_9cc1h ;; get position
ld a,0ffh
cp h
jr nz,sub_9d9ah
ld de,00000h
ld hl,00014h
call 0bbf9h ;; gra line relative
ld de,(data_0a416)
ld hl,0ffech ;; -20
call 0bbc3h ;; gra move relative
pop bc
djnz l9db4h
ld hl,0ffffh
ld (data_0a410),hl
ret
sub_9d9ah:
pop bc
ld (data_0a410),hl
call 0bbc6h ;; gra ask cursor
ld (data_0a412),de
ret
;; screen to buffer
;; c000->5bfe length 3fd0
sub_9da6h:
ld bc,03fd0h
ld hl,0c000h
ld de,05bfeh
ldir
ret
;; buffer to screen
;; 5bfe->c000 length 3fd0
sub_9db2h:
ld bc,03fd0h
ld hl,05bfeh
ld de,0c000h
ldir
ret
sub_9dbeh:
push hl
push de
call sub_09e08h
ld (data_0a414),hl
ld de,05398h
ld b,004h
l9e0bh:
push bc
ld hl,(data_0a414)
ld c,b
ld b,000h
inc hl
and a
sbc hl,bc
ld b,00bh
l9e18h:
ld a,(hl)
ld (de),a
inc de
call 0bc29h ;; scr prev line
djnz l9e18h
pop bc
djnz l9e0bh
pop de
pop hl
ret
sub_9de6h:
push hl
push de
ld de,05398h
ld b,004h
l9e2dh:
push bc
ld hl,(data_0a414)
ld c,b
ld b,000h
inc hl
and a
sbc hl,bc
ld b,00bh
l9e3ah:
ld a,(de)
ld (hl),a
inc de
call 0bc29h ;; scr prev line
djnz l9e3ah
pop bc
djnz l9e2dh
pop de
pop hl
ret
sub_9e08h:
push de
ld de,00002h
call sub_9c94h ;; HL = HL/DE
pop de
push hl
ex de,hl
ld de,(data_0a416)
call sub_9c94h ;; HL = HL/DE
ex de,hl
pop hl
call 0bc1dh ;; scr dot position
ret
sub_9e1fh:
call sub_9c8ah
ld hl,(data_0a418)
ld (data_0a420h),hl
ld hl,(data_0a410)
ld a,0ffh
cp h
ret z
ld (data_a41c),hl
ld de,(data_0a412)
ld (data_a41a),de
l9e7ah:
ld de,0000ah
and a
sbc hl,de
jr nc,l9e85h
ld hl,00000h
l9e85h:
push hl
ld hl,(data_a412)
add hl,de
ex de,hl
pop hl
call sub_09dbeh
call 0bbc0h ;; gra move absolute
sub_9e52h:
call sub_09ed2h
call sub_09de6h
ld hl,(data_a410)
ld a,0ffh
cp h
jr nz,l9ea9h
ld a,02fh
call 0bb1eh ;; km test key
ret z
jp sub_9e52h
l9ea9h:
call sub_09eb7h
ld a,02fh
call 0bb1eh ;; km test key
ret z
ld hl,(data_a41c)
ld de,(data_a41a)
call 0bbc0h ;; gra move absolute
ld hl,(data_a410)
ld de,(data_a412)
ld a,(data_a41e)
call 0bbdeh ;; gra set pen
ld (data_a41c),hl
ld (data_a41a),de
call 0bbf6h ;; gra line absolute
ld hl,(0a410h)
jr l9e7ah
sub_09e98h:
ld de,0ffech
ld hl,00000h
call 0bbc3h ;; gra move relative
ld a,001h
call 0bbdeh ;; gra set pen
call sub_09d35h
ld a,000h
call 0bbdeh ;; gra set pen
call sub_9cc1h ;; get position
ld a,0ffh
cp h
ret nz
pop de
ret
sub_9eb7h:
ld hl,(data_a41a)
ld de,(data_a412)
and a
sbc hl,de
ret z
jp p,l9ecbh
ld hl,l9f15h
jp l09eceh
l9ecbh:
ld hl,sub_9ed2h
l9eceh:
ld (l9e52h+1),hl
ret
sub_9ed2h:
call sub_9e98h
ld de,0ffech
ld hl,00000h
call 0bbc3h ;; gra move relative
ld bc,(data_a420)
push bc
ld de,00000h
ld hl,00014h
call 0bbf9h ;; gra line relative
call sub_9cc1h
ld a,0ffh
cp h
jp nz,sub_9efeh
sub_9ef5h:
ld hl,(data_a422)
ld (data_a410),hl
jp sub_9d9ah
sub_9efeh:
ld (data_a422),hl
ld de,(data_a416)
ld hl,0ffech
call 0bbc3h ;; gra move relative
pop bc
djnz l9f22h
ld hl,0ffffh
ld (data_a410),hl
ret
sub_9f82h:
call sub_9e98h
ld bc,(data_a420)
l9f5ch:
push bc
ld de,00000h
ld hl,00014h
call 0bbf9h ;; gra line relative
call sub_9cc1h
ld a,0ffh
cp h
jp z,sub_9ef5h
ld (data_0a422),hl
ld de,(data_a416)
ld hl,00000h
and a
sbc hl,de
push hl
pop de
ld hl,0ffech
call 0bbc3h ;; gra move relative
pop bc
djnz l9f5ch
ld hl,00000h
ld de,00014h
call 0bbc3h ;; gra move relative
jp l9f0eh
db 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
db 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
db 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
db 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
db 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
db 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
db 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
;; screen dump to printer.
sub_0a028h:
ld a,013h ;; INC instruction
ld (la124),a
ld a,00eh
ld (la0e1+1),a
ld a,(data_a133)
bit 1,a
jr z,la083h
ld a,000h ;; NOP instruction
ld (la124),a
ld a,007h
ld (la0e1+1),a
la083h:
call 0bd28h ;; mc reset printer
ld de,00000h
ld hl,00000h
ld (data_a12d),de
sub_a050h:
ld a,000h
ld (data_a12c),a ;; accumulated pixels.
ld de,(data_a12d)
call sub_a10dh ;; store current graphics position
call 0bbf0h ;; gra test absolute
ld de,00001h
call sub_a11dh ;; get pixel
ld de,00002h
call sub_a11dh ;; get pixel
ld de,00004h
call sub_a11dh ;; get pixel
ld de,00008h
call sub_a11dh ;; get pixel
ld de,00010h
call sub_a11dh ;; get pixel
ld de,00020h
call sub_a11dh ;; get pixel
ld de,00040h
call sub_a0ffh ;; get pixel
la0c9h:
call 0bd2eh ;; mc busy printer
jr c,la0c9h
call 0bd28h ;; mc reset printer
ld a,01bh ;; ESC
call 0bd2bh ;; mc print char
ld a,04bh ;; K
call 0bd2bh ;; mc print char
ld a,000h ;; number of columns low byte
call 0bd2bh ;; mc print char
ld a,(data_a133)
bit 0,a
jr z,la0b4h
ld a,002h ;; number of columns high byte?
call 0bd2bh ;; mc print char
ld a,(data_a12c) ;; pixel data
call 0bd2bh ;; mc print char
jr la0f9h
la0b4h:
ld a,001h ;; number of columns high byte?
call 0bd2bh ;; mc print char
la0f9h:
ld a,(data_a12c) ;; pixel data
call 0bd2bh ;; mc print char
call sub_a115h
inc hl
inc hl
call sub_a10dh
ld a,h
cp 001h
jp nz,sub_a050h
ld a,l
cp 090h
jp nz,sub_a050h
ld a,00ah ;; next line
call 0bd2bh ;; mc print char
ld a,02fh ;; 47 - space
call 0bb1eh ;; km test key
ret nz
ld hl,(data_a12d)
la0e1:
ld de,0000eh
add hl,de
ld (data_a12d),hl
ld hl,00000h
call sub_a10dh
ld de,(data_a12d)
ld a,d
cp 002h
jp nz,sub_a050h
ld a,e
cp 084h
jp nz,sub_a050h
ret
;; accumulate pixels
sub_a0ffh:
ld b,a
call 0bb99h ;; txt get paper
cp b ;; was the colour read the same as the paper?
ret z
;; any pixel which is not the same as the paper will be considered foreground
;; and the printer will draw a dot. Any pixel the same as the paper will
;; be considered background and no dot is drawn by the printer.
;; pixel is set to foreground. accumulate it into the pixel data so far
ld hl,(data_a12c)
add hl,de
ld (data_a12c),hl
ret
sub_a10dh:
ld (data_a12f),hl
ld (data_a131),de
ret
sub_a115h:
ld hl,(data_a12f)
ld de,(data_a131)
ret
sub_a11dh:
call sub_a0ffh ;; accumulate a pixel for printing.
call sub_a115h ;; get current X/Y graphics position
inc de ;; increment X to next pixel accross screen.
la124:
inc de
call sub_a10dh ;; set current X/Y graphics position
call 0bbf0h ;; gra test absolute
ret
data_a12c:
db 00h
data_a12d:
db 84h,02h
data_a12f:
db 00h,00h
data_a131:
dw 000eh
data_a133:
db 00h
data_a134:
db 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
sub_a154h:
call 0bc11h ;; scr get mode
cp 000h
jr nz,la19dh
ld b,004h
la19dh:
cp 001h
jr nz,la1a3h
ld b,002h
la1a3h:
cp 002h
jr nz,la1a9h
ld b,001h
la1a9h:
ld a,b
la1aah:
ld (data_a254),a
call 0bbc6h ;; gra ask cursor
ld (data_a250),hl
ld (data_a250+2),de
la1b7h:
call 0bb99h ;; txt get paper
ld (pen_cmp+1),a
ld bc,00000h
ld (data_a24c),bc
ld (data_a24e),bc
call sub_a210
la18bh:
ld a,02fh ;; 47 - space
call 0bb1eh ;; km test key
ret nz
ld hl,(data_a24e)
inc hl
inc hl
ld a,004h
cp h
jr nz,la1deh
ld hl,00000h
la1deh:
ld (data_a24e),hl
ld bc,05398h
add hl,bc
ld (buffer_addr3+2),hl ;; +2 to skip ED,53
buffer_addr3:
ld de,(055e0h)
ld hl,(data_a24e)
sub_a1efh:
ld bc,057e4h
add hl,bc
ld (buffer_addr4+1),hl ;; +1 to skip 22
buffer_addr4:
ld hl,(05a2ch)
ld (data_a257),hl
ld (data_a255),de
ld bc,00000h
ld a,(data_a254)
ld c,a
ex de,hl
add hl,bc
ex de,hl
call sub_a1efh
and a
ex de,hl
sbc hl,bc
ex de,hl
call sub_a1efh
inc hl
inc hl
call sub_a1efh
dec hl
dec hl
call sub_a1efh
ld hl,(data_a24e)
ld de,(data_a24c)
inc hl
inc hl
and a
sbc hl,de
ret z
jp la18bh
sub_a1efh:
push de
push hl
push bc
call 0bbf0h ;; gra test absolute
pop bc
pop hl
pop de
pen_cmp:
cp 000h
jr nz,la248h
ld (data_a250),hl
ld (data_a252),de
push bc
call sub_0a210h
pop bc
la248h:
ld hl,(data_a257)
ld de,(data_a255)
ret
sub_a210:
ld hl,(data_a250)
ld de,(data_a252)
call 0bbeah ;; gra plot absolute
ld hl,(data_a24c)
inc hl
inc hl
ld a,004h
cp h
jr nz,la267h
ld hl,00000h
la267h:
ld (data_a24c),hl
ld bc,05398h
add hl,bc
ld de,(data_a252)
ld (buffer_addr1+2),hl ;; +2 to skip ED, 53
buffer_addr1:
ld (05648h),de
ld hl,(data_a24c)
ld bc,057e4h
add hl,bc
ld de,(data_a250)
ld (buffer_addr+2),hl ;; +2 to skip ED, 53
buffer_addr2:
ld (05a94h),de
ret
;;Data area
data_a24c:
defw 02b0h
data_a24e:
defw 0248h
data_a250:
defw 0beh
data_a252:
defw 0120h
data_a254:
defb 04h
data_a255:
defw 0120h
data_a257:
defw 0bch
;; detected light pen position
data_a410:
defw 0
data_a412:
defw 0
;; memory/buffer address
data_a414:
defw 0
data_a416:
defw 0
data_a418:
defw 0
;; gra x,y position
data_a41a:
defw 0
data_a41c:
defw 0
;; graphics pen
data_a41e:
defb 0
defb 0
data_a420:
defw 0
end
