sb: use qboot

This commit is contained in:
Vince Weaver 2023-05-26 00:18:33 -04:00
parent b2c4346a20
commit 68dab4547d
13 changed files with 961 additions and 13 deletions

34
basic/tic/Makefile Normal file
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@ -0,0 +1,34 @@
include ../../Makefile.inc
DOS33 = ../../utils/dos33fs-utils/dos33
TOKENIZE = ../../utils/asoft_basic-utils/tokenize_asoft
EMPTY_DISK = ../../empty_disk/empty.dsk
all: tic.dsk
tic.dsk: HELLO PLASMA.BAS ROTOZOOM.BAS
cp $(EMPTY_DISK) tic.dsk
$(DOS33) -y tic.dsk SAVE A HELLO
$(DOS33) -y tic.dsk SAVE A PLASMA.BAS
$(DOS33) -y tic.dsk SAVE A ROTOZOOM.BAS
####
HELLO: hello.bas
$(TOKENIZE) < hello.bas > HELLO
####
PLASMA.BAS: plasma.bas
$(TOKENIZE) < plasma.bas > PLASMA.BAS
####
ROTOZOOM.BAS: rotozoom.bas
$(TOKENIZE) < rotozoom.bas > ROTOZOOM.BAS
####
clean:
rm -f *~ *.o *.lst HELLO PLASMA.BAS

2
basic/tic/hello.bas Normal file
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@ -0,0 +1,2 @@
5 HOME
10 PRINT CHR$(4);"CATALOG"

21
basic/tic/plasma.bas Normal file
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@ -0,0 +1,21 @@
'function TIC()
' t=time()/499
' for i=0,32639 do
' x=i%240
' y=i/240
' v=s(x/50+t)+s(y/22+t)+s(x/32)
' poke4(i,v*2%8)
' end
'end
's=math.sin
5 HGR2
10 FOR X=0 TO 279
20 FOR Y=0 TO 191
30 V=SIN(X/50+T)+SIN(Y/22+T)+SIN(X/32)
35 V=INT(V*3.5+3.5)
37 IF V>7 THEN V=V-7
38 IF V<0 THEN V=V+7
40 HCOLOR=V:HPLOT X,Y
50 NEXT Y,X
60 T=T+(1/499):GOTO 10

23
basic/tic/rotozoom.bas Normal file
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@ -0,0 +1,23 @@
'function TIC()
' t=time()/999
' a=s(t-11)
' b=s(t)
' for i=0,32639 do
' x=i%240-120
' y=i/240-68
' u=a*x-b*y
' v=b*x+a*y
' poke4(i,(u//1~v//1)//16)
' end
'end
's=math.sin
' // is floor division, ~ is bitwise XOR. That's hard in applesoft
10 HGR2
20 A=SIN(T-11)
30 B=SIN(T)
40 FOR X=-140 TO 139
50 FOR Y=0 TO 192
60 U=A*X-B*Y
70 V=B*X+A*Y

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@ -4,6 +4,7 @@ ZX02 = ~/research/6502_compression/zx02.git/build/zx02
PNG_TO_HGR = ../../utils/hgr-utils/png2hgr PNG_TO_HGR = ../../utils/hgr-utils/png2hgr
LINKER_SCRIPTS = ../../linker_scripts LINKER_SCRIPTS = ../../linker_scripts
DOS33 = ../../utils/dos33fs-utils/dos33 DOS33 = ../../utils/dos33fs-utils/dos33
DOS33_RAW = ../../utils/dos33fs-utils/dos33_raw
EMPTY_DISK = ../../empty_disk/empty.dsk EMPTY_DISK = ../../empty_disk/empty.dsk
TOKENIZE = ../../utils/asoft_basic-utils/tokenize_asoft TOKENIZE = ../../utils/asoft_basic-utils/tokenize_asoft
@ -11,18 +12,41 @@ all: sb.dsk
#### ####
sb.dsk: HELLO TITLE DUCK_POND SB FN sb.dsk: QBOOT QLOAD TITLE DUCK_POND SB FN
cp $(EMPTY_DISK) sb.dsk cp $(EMPTY_DISK) sb.dsk
$(DOS33) -y sb.dsk SAVE A HELLO $(DOS33_RAW) sb.dsk 0 0 QBOOT 0 1
$(DOS33) -y sb.dsk BSAVE -a 0x0c00 TITLE $(DOS33_RAW) sb.dsk 0 2 QBOOT 1 1
$(DOS33) -y sb.dsk BSAVE -a 0x1000 DUCK_POND $(DOS33_RAW) sb.dsk 0 4 QBOOT 2 1
$(DOS33) -y sb.dsk BSAVE -a 0x0c00 SB $(DOS33_RAW) sb.dsk 1 0 QLOAD 0 0
$(DOS33) -y sb.dsk BSAVE -a 0x6000 FN $(DOS33_RAW) sb.dsk 2 0 TITLE 0 0
$(DOS33_RAW) sb.dsk 5 0 DUCK_POND 0 0
$(DOS33_RAW) sb.dsk 8 0 SB 0 0
$(DOS33_RAW) sb.dsk 11 0 FN 0 0
# $(DOS33) -y sb.dsk BSAVE -a 0x1000 DUCK_POND
# $(DOS33) -y sb.dsk BSAVE -a 0x0c00 SB
# $(DOS33) -y sb.dsk BSAVE -a 0x6000 FN
#### ####
QBOOT: qboot_sector.o
ld65 -o QBOOT qboot_sector.o -C $(LINKER_SCRIPTS)/apple2_800.inc
qboot_sector.o: qboot_sector.s qboot_stage2.s
ca65 -o qboot_sector.o qboot_sector.s -l qboot_sector.lst
####
QLOAD: qload.o
ld65 -o QLOAD qload.o -C $(LINKER_SCRIPTS)/apple2_1200.inc
qload.o: qload.s qboot.inc
ca65 -o qload.o qload.s -l qload.lst
####
SB: sb.o SB: sb.o
ld65 -o SB sb.o -C $(LINKER_SCRIPTS)/apple2_c00.inc ld65 -o SB sb.o -C $(LINKER_SCRIPTS)/apple2_6000.inc
sb.o: sb.s zx02_optim.s \ sb.o: sb.s zx02_optim.s \
zp.inc hardware.inc zp.inc hardware.inc
@ -50,7 +74,7 @@ fn.o: fn.s zx02_optim.s duet.s hgr_sprite_mask.s hgr_sprite.s hgr_tables.s \
#### ####
TITLE: title.o TITLE: title.o
ld65 -o TITLE title.o -C $(LINKER_SCRIPTS)/apple2_c00.inc ld65 -o TITLE title.o -C $(LINKER_SCRIPTS)/apple2_6000.inc
title.o: title.s zx02_optim.s \ title.o: title.s zx02_optim.s \
zp.inc hardware.inc zp.inc hardware.inc
@ -60,7 +84,7 @@ title.o: title.s zx02_optim.s \
#### ####
DUCK_POND: duck_pond.o DUCK_POND: duck_pond.o
ld65 -o DUCK_POND duck_pond.o -C $(LINKER_SCRIPTS)/apple2_1000.inc ld65 -o DUCK_POND duck_pond.o -C $(LINKER_SCRIPTS)/apple2_6000.inc
duck_pond.o: duck_pond.s zx02_optim.s \ duck_pond.o: duck_pond.s zx02_optim.s \
zp.inc hardware.inc \ zp.inc hardware.inc \

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@ -59,7 +59,7 @@ title_screen:
lda #>title_data lda #>title_data
sta ZX0_src+1 sta ZX0_src+1
lda #$C ; load at $c00 lda #$c ; load at $C00
jsr full_decomp jsr full_decomp
@ -111,7 +111,7 @@ init_game:
lda #>main_data lda #>main_data
sta ZX0_src+1 sta ZX0_src+1
lda #$C lda #$c
jsr full_decomp jsr full_decomp

8
games/sb/qboot.inc Normal file
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@ -0,0 +1,8 @@
seek = $1126
driveon = $119D
driveoff = $1122
load_new = $11AB
load_address=$11C4
load_track=load_address+1
load_sector=load_address+2
load_length=load_address+3

244
games/sb/qboot_sector.s Normal file
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; fast seek/multi-read
; copyright (c) Peter Ferrie 2015-16
; Paramaters for loading QLOAD
sectors = 14 ; user-defined
firsttrk = 1 ; user-defined, first track to read
firstsec = 0 ; user-defined, first sector to read
address = $12 ; user-defined
entry = $1200 ; user-defined
version = 1
;memory usage:
;256 bytes ($200-2ff) static table
grouped = $200
; stay away from interrupt vectors at $3fe !!!
;106 bytes ($300-369) static table
preshift = $300
zvalue = $fd ; only during init
znibble = $fe ; only during init
zmask = $ff ; only during init
WHICH_SLOT = $DA
; $26/$27 sector read location (ROM)
; $3D sector number (ROM)
; at entry (at least on AppleWin) A=1, X=60 (slot<<4), Y=0
; qkumba says cffa cards leave Y at $10
; 26/27 = 00/09
; 3D = 1
; For Disk II booting, the firmware loads track0/sector0
; to $800 and then jumps to $801
.org $800
.byte 1 ; number of sectors for ROM to load
boot_entry:
; this code loads two sectors up to $10/$11
; assume A=1 coming in here
lsr ; check sector number
; A=0, carry=1
tay ; Y=0
adc #$0f ; A=$10 (destintation)
sta $27 ; set or update address as needed
cmp #$12
; 10 11 12 (1 1 1)
; be, bf, c0 (1011 1011 1100)
; so if hit $c000 we are done
beq done_load_2 ; branch if loaded 2
inc $3d ; increment sector (faster to find)
; call to the read routine in proper slot
; using rts to jump indirect to
; $CX5C
; this routine reads sector in $3D on track in $41
; to address in $26/$27
; when it's done it jumps back to $801
stx WHICH_SLOT ; save for later
txa ; x is slot# << 4
lsr
lsr
lsr
lsr
ora #$c0 ; slot to PROM base
pha
lda #$5b ;read-1
pha
rts ; return used to call $CX5C in DISK II ROM
done_load_2:
; patch self modifying code for Q6L read
txa
ora #$8c ; slot to Q6L
; Q6L?
; if slot 6, after this A is $EC
; Y should be 2 here
patch_loop:
iny
ldx patchtbl-3, Y
sta code_begin, X ; replace placeholders with Q6L
; BE02 = EC? lda c0ec
; so sets to c08c (Q6L)
bne patch_loop
; patch self-modifying code for turning motor off
and #$f8 ; MOTOROFF (c088) -> c0e8
sta slotpatch7+1
; patch self-modifying code for turning motor on
clc
adc #1 ; MOTORON (c089) -> c0e9
sta slotpatch9+1
; patch self-modifying code for phase off
eor #9 ; PHASEOFF (c080)
sta slotpatch8+1
ldx #$3f
stx zmask
inx
ldy #$7f
bne skip_ahead ; branch always
; pad with zeros until $839
; $839 is the entry point
; adjusts address at $8FE to be entry point
; jumps to boot 2
;.res $839-*
; lda #>(entry-1)
; pha
; lda #<(entry-1)
; pha
; jsr preread
; jmp $1000 ; stage2 entry point
patchtbl:
.byte <(slotpatch1+1), <(slotpatch2+1), <(slotpatch3+1)
.byte <(slotpatch4+1), <(slotpatch5+1), <(slotpatch6+1)
indextbl: ;the 0 also terminates the patchtbl list!
.byte 0, 2, 1, 3
;construct denibbilisation table
;pre-shifted for interleave read
skip_ahead:
loopaa:
sty znibble
tya
asl
bit znibble
beq loopz
ora znibble
eor #$ff
and #$7e
loopa:
bcs loopz
lsr
bne loopa
dex
txa
asl
asl
sta preshift-$16, Y
loopz:
dey
bne loopaa
;construct 2-bit group table
sty zvalue
loopbb:
lsr zmask
lsr zmask
loopb:
lda indextbl, X
sta grouped, Y
inc zvalue
lda zvalue
and zmask
bne loopy
inx
txa
and #3
tax
loopy:
iny
iny
iny
iny
cpy #3
bcs loopb
iny
cpy #3
bcc loopbb
lda #>(entry-1)
pha
lda #<(entry-1)
pha
jsr preread
; seek backward support
; sty startsec+1
; sta tmpadr+1
; stx total+1
jmp seekread
preread:
;copy post-read if necessary
;push post-read address here
; pla
; tax
; pla
; tay
; lda #>(postread-1)
; pha
; lda #<(postread-1)
; pha
; tya
; pha
; txa
; pha
lda #<(firsttrk*2)
sta phase+1
ldx #sectors
lda #address
ldy #firstsec
rts
end_code:
.res $8fe-*
; traditionally, entry point to jump to at end of loading
; $1000 in this case
;*=$8fe
.byte $10, $00
.include "qboot_stage2.s"

382
games/sb/qboot_stage2.s Normal file
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@ -0,0 +1,382 @@
; the following lives on sectors $0E and $0D
; why?
; request sector 2 and 4, and the interleave is
; beneath apple dos (3-23)
; Physical (firmware) : 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
; DOS33 mapping : 0, 7, 14, 6, 13, 5, 12, 4, 11, 3, 10, 2, 9, 1, 8, 15
; Beneath Apple DOS
; p86 (dos reference)
;
;WAIT = $FCA8 ;; delay 1/2(26+27A+5A^2) us
WAIT = norom_wait
.org $1000
code_begin:
.byte version
readnib:
slotpatch1: ; smc
lda $c0d1 ; gets set to C08C (Q6L) read
bpl readnib
rts
;fill address array for one track
seekread:
sty startsec+1
sta tmpadr+1
stx total+1
inittrk:
sec
lda #$10
sbc startsec+1
cmp total+1
bcs it_skip
tax
it_skip:
stx partial1
stx partial2
jsr seek
startsec:
ldy #$d1
tmpadr:
tmpadr_loop:
lda #$d1
sta addrtbl, y
inc tmpadr+1
iny
dec partial1
bne tmpadr_loop
;====================================
; read a sector
;====================================
; first address field
;====================================
; starts with $D5 $AA $96
; then XX YY volume
; then XX YY track
; then XX YY sector
; then XX YY checksum
; then ends with $DE $AA $EB
;====================================
; data field
;====================================
; starts with $D5 $AA $AD
; 342 bytes of data
; XX checksum
; ends with $DE $AA $EB
read:
outer_read:
jsr readnib
inner_read:
cmp #$d5 ; look for $D5 part of addr field
bne outer_read
jsr readnib ; look for $D5 $AA
cmp #$aa
bne inner_read
; look for $D5 $AA $AD
tay ; we need Y=#$AA later
jsr readnib
eor #$ad ; zero A if match
beq check_mode
; if not #$AD, then #$96 is assumed
; so in address field
ldy #2 ; volume, track, sector
another:
jsr readnib
rol ; set carry
sta sector+1
jsr readnib
and sector+1
dey
bpl another
tay
ldx addrtbl, Y ; fetch corresponding address
beq read ; done?
sta sector+1 ; store index for later
stx adrpatch1+2
stx adrpatch8+2
stx adrpatch2+2
stx adrpatch3+2
stx adrpatch5+2
stx adrpatch7+2
inx
stx adrpatch9+2
dex
dex
stx adrpatch4+2
stx adrpatch6+2
ldy #$fe
loop2:
adrpatch1:
lda $d102, Y
pha
iny
bne loop2
branch_read:
bcs read ; branch always
check_mode:
cpx #0
beq read ; loop if not expecting #$AD
loop33:
sta tmpval+1 ; zero rolling checksum
slotpatch2:
loop4:
ldx $c0d1
bpl loop4
lda preshift-$96, X
adrpatch2:
sta $d102, Y ; store 2-bit array
tmpval:
eor #$d1
iny
bne loop33
ldy #$aa
slotpatch3:
loop5:
ldx $c0d1
bpl loop5
eor preshift-$96, X
adrpatch3:
ldx $d102, Y ; bit2tbl
eor grouped+2, X ; first 86 nibbles use group bits 0-1
adrpatch4:
sta $d156, y
iny
bne loop5
and #$fc
ldy #$aa
slotpatch4:
loop6:
ldx $c0d1
bpl loop6
eor preshift-$96, X
adrpatch5:
ldx $d102, Y ; bit2tbl
eor grouped+1, X ; second 86 nibbles use group bits 2-3
adrpatch6:
sta $d1ac, Y
iny
bne loop6
and #$fc
ldx #$ac
slotpatch5:
loop7:
ldy $c0d1
bpl loop7
eor preshift-$96, Y
adrpatch7:
ldy $d100, X ; bit2tbl
eor grouped, Y ; last 84 nibbles use group bits 4-5
adrpatch8:
sta $d100, x
inx
bne loop7
and #$fc
slotpatch6:
loop8:
ldy $c0d1
bpl loop8
eor preshift-$96, Y
cmp #1 ; carry = !zero
ldy #1
loop9:
pla
adrpatch9:
sta $d100, Y
dey
bpl loop9
branch_read2:
bcs branch_read ; branch if checksum failure
sector:
ldy #$d1
txa
sta addrtbl, Y ; zero corresponding address
dec total+1
dec partial2 ; adjust remaining count
; (faster than looping over array)
sec
bne branch_read2 ; read all requested sectors in one track
sta startsec+1 ; this was missing from original code
; leading to trouble on wrap around
; it not starting at sector0
total:
ldx #$d1
beq driveoff
inc phase+1
inc phase+1 ; update current track
jmp inittrk
driveoff:
slotpatch7:
lda $c0d1
seekret:
rts
seek:
ldx #0
stx step+1
copy_cur:
curtrk:
lda #0
sta tmpval+1
sec
phase:
sbc #$d1
beq seekret
; if seek backwards
bcs sback
eor #$ff
inc curtrk+1
bcc ssback
sback:
adc #$fe
dec curtrk+1
ssback:
cmp step+1
bcc loop10
step:
lda #$d1
loop10:
cmp #8
bcs loop11
tay
sec
loop11:
lda curtrk+1
ldx step1, Y
bne loop12
loopmmm:
clc
lda tmpval+1
ldx step2, Y
loop12:
stx sector+1
and #3
rol
tax
slotpatch8:
sta $c0d1, X
loopmm:
ldx #$13
loopm:
dex
bne loopm
dec sector+1
bne loopmm
lsr
bcs loopmmm
inc step+1
bne copy_cur
step1: .byte 1, $30, $28, $24, $20, $1e, $1d, $1c
step2: .byte $70, $2c, $26, $22, $1f, $1e, $1d, $1c
addrtbl: .res 16
partial1: .byte $00
partial2: .byte $00
code_end:
;==========================
; enable drive motor
;==========================
driveon:
slotpatch9:
lda $c0d1
; wait 1s
ldx #6
wait_1s:
lda #255
jsr WAIT
dex
bne wait_1s
rts
load_new:
jsr driveon
lda load_track
asl ; track to start*2
sta phase+1
lda load_sector
tay ; sector to start
lda load_length ; length
tax
lda load_address ; address to load
jsr seekread
rts
load_address:
.byte $00
load_track:
.byte $00
load_sector:
.byte $00
load_length:
.byte $00
; copy of ROM wait
; because we might disable ROM
norom_wait:
sec
wait2:
pha
wait3:
sbc #$01
bne wait3
pla
sbc #$01
bne wait2
rts
wait_end:

192
games/sb/qload.s Normal file
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@ -0,0 +1,192 @@
; Loader for sb
.include "zp.inc"
.include "hardware.inc"
;.include "common_defines.inc"
.include "qboot.inc"
qload_start:
; init the write code
; lda WHICH_SLOT
; jsr popwr_init
; first time entry
; start by loading text title
lda #0 ; load LEMM engine
sta WHICH_LOAD
lda #1
sta CURRENT_DISK ; current disk number
forever_loop:
jsr load_file
jsr $6000 ; jump to loaded file
jmp forever_loop
;====================================
; loads file specified by WHICH_LOAD
;====================================
load_file:
ldx WHICH_LOAD
lda which_disk_array,X
cmp CURRENT_DISK
bne change_disk
load_file_no_diskcheck:
lda load_address_array,X
sta load_address
lda track_array,X
sta load_track
lda sector_array,X
sta load_sector
lda length_array,X
sta load_length
jsr load_new
rts
;===================================================
;===================================================
; change disk
;===================================================
;===================================================
change_disk:
.if 0
; turn off disk drive light
jsr driveoff
jsr TEXT
jsr HOME
lda #<error_string
sta OUTL
lda #>error_string
sta OUTH
ldx WHICH_LOAD
lda which_disk_array,X
clc
adc #48
ldy #19
sta (OUTL),Y
ldy #0
quick_print:
lda (OUTL),Y
beq quick_print_done
jsr COUT1
iny
jmp quick_print
quick_print_done:
fnf_keypress:
lda KEYPRESS
bpl fnf_keypress
bit KEYRESET
;==============================================
; actually verify proper disk is there
; read T0:S0 and verify proper disk
lda WHICH_LOAD
pha
ldx #LOAD_FIRST_SECTOR ; load track 0 sector 0
stx WHICH_LOAD
jsr load_file_no_diskcheck
pla
sta WHICH_LOAD
tax
; first sector now in $c00
; offset 59
; disk1 = $0a
; disk2 = $32 ('2')
; disk3 = $33 ('3')
lda $c59
cmp #$0a
beq is_disk1
cmp #$32
beq is_disk2
cmp #$33
beq is_disk3
bne change_disk ; unknown disk
is_disk1:
lda #1
bne disk_compare
is_disk2:
lda #2
bne disk_compare
is_disk3:
lda #3
disk_compare:
cmp which_disk_array,X
bne change_disk ; disk mismatch
;==============================================
; all good, retry original load
jsr HOME
ldx WHICH_LOAD
lda which_disk_array,X
sta CURRENT_DISK
jmp load_file
; offset for disk number is 19
error_string:
.byte "PLEASE INSERT DISK 1, PRESS RETURN",0
.endif
which_disk_array:
.byte 1,1,1,1 ; TITLE, DUCK, SB, FN
.byte 1,1,1,1 ; LEVEL4, LEVEL5, LEVEL6, LEVEL7
.byte 1,1,1,1 ; LEVEL8, LEVEL9, LEVEL10
load_address_array:
.byte $60,$60,$60,$60 ; TITLE, DUCK, SB, FN
.byte $90,$90,$90,$90 ; LEVEL4, LEVEL5, LEVEL6, LEVEL7
.byte $90,$90,$90,$90 ; LEVEL8, LEVEL9, LEVEL10
track_array:
.byte 2, 5, 8,11 ; TITLE, DUCK, SB, FN
.byte 15,18,21,24 ; LEVEL4, LEVEL5, LEVEL6, LEVEL7
.byte 27,30,33,33 ; LEVEL8, LEVEL9, LEVEL10
sector_array:
.byte 0, 0, 0, 0 ; TITLE, DUCK, SB, FN
.byte 0, 0, 0, 0 ; LEVEL4, LEVEL5, LEVEL6, LEVEL7
.byte 0, 0, 0, 0 ; LEVEL8, LEVEL9, LEVEL10
length_array:
.byte 16, 16, 16, 32 ; TITLE, DUCK, SB, FN
.byte 46, 46, 46, 46 ; LEVEL4, LEVEL5, LEVEL6, LEVEL7
.byte 46, 46, 32, 32 ; LEVEL8, LEVEL9, LEVEL10
qload_end:
.assert (>qload_end - >qload_start) < $e , error, "loader too big"

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@ -57,7 +57,10 @@ wait_until_keypress:
bit KEYRESET ; clear the keyboard buffer bit KEYRESET ; clear the keyboard buffer
which_ok: which_ok:
jmp load_loop lda #0
sta WHICH_LOAD
rts

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@ -56,11 +56,22 @@ wait_until_keypress:
bpl wait_until_keypress ; 3 bpl wait_until_keypress ; 3
bit KEYRESET ; clear the keyboard buffer bit KEYRESET ; clear the keyboard buffer
and #$7f
cmp #'1'
bcc which_ok
cmp #'4'
bcs which_ok
jmp done
which_ok: which_ok:
jmp load_loop jmp load_loop
done:
and #$f
sta WHICH_LOAD
rts
.include "zx02_optim.s" .include "zx02_optim.s"

View File

@ -10,6 +10,8 @@ ZX0_dst = ZP+4
bitr = ZP+6 bitr = ZP+6
pntr = ZP+7 pntr = ZP+7
WHICH_LOAD = $09
;; Zero page monitor routines addresses ;; Zero page monitor routines addresses
WNDLFT = $20 WNDLFT = $20
@ -124,6 +126,8 @@ LYRICS_ACTIVE = $9B
;FORTYCOL = $9C ;FORTYCOL = $9C
CURSOR = $9D CURSOR = $9D
CURRENT_DISK = $DC
; More zero-page addresses ; More zero-page addresses
; we try not to conflict with anything DOS, MONITOR or BASIC related ; we try not to conflict with anything DOS, MONITOR or BASIC related