commit whatever is in my worktree rn
This commit is contained in:
parent
1dea0c40bc
commit
a3ef693059
|
|
@ -7,11 +7,8 @@ banner: db "RDOS KERNEL ", V, 0x0A, 0x0D, '$', 0x1A
|
|||
|
||||
%include "kernel/far.asm"
|
||||
%include "kernel/char.asm"
|
||||
%include "inc/bpb.asm"
|
||||
%include "kernel/drive.asm"
|
||||
%include "kernel/fcb.asm"
|
||||
%include "kernel/rootdir.asm"
|
||||
%include "kernel/cluster.asm"
|
||||
%include "kernel/fat.asm"
|
||||
|
||||
section .text
|
||||
|
||||
|
|
@ -21,32 +18,15 @@ init: call rstseg
|
|||
mov dx, banner
|
||||
call puts
|
||||
|
||||
call rstseg
|
||||
mov dx, testdta
|
||||
push ds
|
||||
call norm
|
||||
call setdta
|
||||
pop ds
|
||||
mov dl, 0
|
||||
call select
|
||||
|
||||
mov dx, testfcb
|
||||
call norm
|
||||
|
||||
call open
|
||||
|
||||
call read
|
||||
|
||||
mov ax, [cs:testdta]
|
||||
mov cx, [cs:testdta+2]
|
||||
int 3
|
||||
mov dx, 3
|
||||
call setclus
|
||||
call rdfat
|
||||
mov dx, bx
|
||||
inc dx
|
||||
call wdfat
|
||||
|
||||
hlt: hlt
|
||||
jmp hlt
|
||||
|
||||
section .data
|
||||
|
||||
testfcb db 0, "HELLO ","COM"
|
||||
times FCBSIZ db 0
|
||||
|
||||
section .bss
|
||||
|
||||
testdta resb 128
|
||||
|
|
|
|||
163
com/a86.asm
163
com/a86.asm
|
|
@ -43,10 +43,6 @@ dmpdx3: int 0x10
|
|||
free dw 0 ; free ram size
|
||||
lncnt dw 0 ; line count
|
||||
rdptr dw 0xFFFF ; infile blk ptr
|
||||
symbol dw 0 ; symbol of current line
|
||||
offset dw 0 ; byte offset in outfile
|
||||
len db 0 ; len for wrd (must be before it)
|
||||
wrd dw 0,0,0,0,0,0,0,0 ; 16 byte word buf
|
||||
|
||||
getc mov bx, [rdptr]
|
||||
cmp bx, 0x80
|
||||
|
|
@ -72,12 +68,6 @@ l02 mov al, 0x1A
|
|||
l03 cmp al, eof
|
||||
ret
|
||||
|
||||
;getc2 call peek
|
||||
; cmp al, eof
|
||||
; jne getc_
|
||||
; inc word [rdptr]
|
||||
;getc_ ret
|
||||
|
||||
newlin mov dl, 0x0A
|
||||
mov ah, 2
|
||||
int 0x21
|
||||
|
|
@ -99,145 +89,32 @@ error mov dl, [bx]
|
|||
e_eof db "EOF "
|
||||
e_dup db "DUPSYM "
|
||||
|
||||
; scan word
|
||||
scawrd mov si, wrd
|
||||
l04 call getc
|
||||
; EOF is fatal
|
||||
mov bx, e_eof
|
||||
jz error
|
||||
; tab=end
|
||||
cmp al, 9
|
||||
je pad
|
||||
; space=end
|
||||
cmp al, 0x20
|
||||
je pad
|
||||
; if lbl full, continue eating
|
||||
cmp si, wrd+0x10
|
||||
jnc l04
|
||||
; insert
|
||||
mov [si], al
|
||||
inc si
|
||||
jmp l04
|
||||
; pad with spaces
|
||||
pad mov cx, si
|
||||
sub cx, wrd
|
||||
mov [len], cl
|
||||
cmp si, wrd+0x10
|
||||
jnc l06
|
||||
mov ah, 0x20
|
||||
xchg ah, [si]
|
||||
inc si
|
||||
cmp ah, 0x20
|
||||
jne pad
|
||||
l06 ret
|
||||
tok1:
|
||||
s_ws db " " ; also used for tabs
|
||||
s_com db ","
|
||||
s_obr db "["
|
||||
s_cbr db "]"
|
||||
s_plu db "+"
|
||||
s_min db "-"
|
||||
|
||||
; print wrd
|
||||
dmpwrd mov si, wrd
|
||||
mov cx, 0x10
|
||||
mov ah, 2
|
||||
l05 mov dl, [si]
|
||||
cmp dl, 0x20
|
||||
je l07
|
||||
inc si
|
||||
int 0x21
|
||||
loop l05
|
||||
l07 call newlin
|
||||
ret
|
||||
align 2
|
||||
tok2:
|
||||
reg8 db "AL","CL","DL","BL","AH","CH","DH","BH"
|
||||
reg16 db "AX","CX","DX","BX","SP","BP","SI","DI"
|
||||
sreg db "ES","CS","SS","DS"
|
||||
s_db db "DB"
|
||||
s_dw db "DW"
|
||||
|
||||
; create symbol table entry
|
||||
; name is read from [wrd]
|
||||
; offset is written to [symbol]
|
||||
symins cmp byte [wrd], 0x20
|
||||
je nosym
|
||||
mov bx, init ; walk ptr
|
||||
mov bp, [free]
|
||||
add bp, bx ; end addr
|
||||
jmp l09
|
||||
l08 add bx, 8
|
||||
l09 mov al, [bx]
|
||||
cmp al, 0
|
||||
je l10
|
||||
call symcmp
|
||||
jnz l08
|
||||
mov bx, e_dup
|
||||
jmp error
|
||||
; copy str to table
|
||||
l10 mov si, wrd
|
||||
mov di, bx
|
||||
movsw
|
||||
movsw
|
||||
movsw
|
||||
xor ax, ax
|
||||
stosw
|
||||
mov byte [bx+8], 0
|
||||
mov [symbol], bx
|
||||
ret
|
||||
tok3:
|
||||
s_org db "ORG"
|
||||
s_equ db "EQU"
|
||||
|
||||
nosym xor ax, ax
|
||||
mov [symbol], ax
|
||||
ret
|
||||
|
||||
; compares 6 bytes [bx] with [wrd]
|
||||
; bit 7 of each byte is ignored
|
||||
symcmp mov si, wrd
|
||||
xor ax, ax
|
||||
mov dx, [wrd]
|
||||
xor dx, [bx]
|
||||
or ax, dx
|
||||
mov dx, [wrd+2]
|
||||
xor dx, [bx+2]
|
||||
or ax, dx
|
||||
mov dx, [wrd+4]
|
||||
xor dx, [bx+4]
|
||||
or ax, dx
|
||||
test ax, 0x8F8F
|
||||
ret
|
||||
|
||||
; look up keyword in wrd
|
||||
; result is stored in bx
|
||||
lookup mov ch, 0
|
||||
mov bx, s_org
|
||||
l11 mov si, bx
|
||||
mov di, len ; wrd immediately follows
|
||||
mov cl, [bx]
|
||||
test cx, cx
|
||||
jz l13
|
||||
inc cl
|
||||
mov dx, cx
|
||||
rep cmpsb
|
||||
je l12
|
||||
add bx, dx
|
||||
jmp l11
|
||||
; found!
|
||||
l12 clc
|
||||
ret
|
||||
; give up
|
||||
l13 xor bx, bx
|
||||
stc
|
||||
ret
|
||||
|
||||
s_org db 3, "org"
|
||||
s_equ db 3, "equ"
|
||||
db 0
|
||||
; TODO: parse a line into wordlist of tokens and ptrs to strings
|
||||
rline: ret
|
||||
|
||||
; clear symbol table
|
||||
main mov byte [init], 0
|
||||
; scan and create label
|
||||
mloop call scawrd
|
||||
call symins
|
||||
; scan instruction word
|
||||
call scawrd
|
||||
call lookup
|
||||
; special stuff
|
||||
cmp bx, s_org
|
||||
je iorg
|
||||
mov ax, bx
|
||||
call dumpax
|
||||
int 0x20
|
||||
|
||||
; org pseudo instruction
|
||||
iorg mov ax, 0x5A5A
|
||||
call dumpax
|
||||
call rline
|
||||
int 0x20
|
||||
|
||||
align 16
|
||||
|
|
|
|||
|
|
@ -5,6 +5,34 @@
|
|||
; - dirty: inform that dskbuf has been written to
|
||||
; access is done by accessing dskbuf directly
|
||||
|
||||
BPBOFF equ 0xB
|
||||
|
||||
; DOS 2.0 BPB
|
||||
BPBSS equ 0 ; word
|
||||
BPBSC equ 2 ; byte
|
||||
BPBRSC equ 3 ; word
|
||||
BPBFN equ 5 ; byte
|
||||
BPBRDE equ 6 ; word
|
||||
BPBTS equ 8 ; word
|
||||
BPBMD equ 10 ; byte
|
||||
BPBFS equ 11 ; word
|
||||
BPBSIZ2 equ 13 ; size constant
|
||||
|
||||
; DOS 3.31 BPB
|
||||
BPBSPT equ 0x0D ; word
|
||||
BPBNOS equ 0x0F ; word
|
||||
BPBHS equ 0x11 ; dword
|
||||
BPBLTS equ 0x15 ; dword
|
||||
BPBSIZ3 equ 25 ; size constant
|
||||
|
||||
; DOS 3.4 EBPB
|
||||
BPBDN equ 0x19 ; byte
|
||||
BPBFALG equ 0x1A ; byte
|
||||
BPBSIG equ 0x1B ; byte
|
||||
BPBSER equ 0x1C ; dword serial number
|
||||
BPBSIZ4 equ 32 ; size constant
|
||||
|
||||
; Disk parameter table (int 1E)
|
||||
DPTSIZE equ 11
|
||||
DPTSPT equ 4
|
||||
|
||||
|
|
@ -94,10 +122,10 @@ getprm test byte [dskflag], 4
|
|||
call lodfar
|
||||
.ret ret
|
||||
|
||||
; log in drive
|
||||
; select a drive for io
|
||||
; IN dl drive number
|
||||
; dont do anything if drive already selected
|
||||
logdrv cmp dl, [dsknum]
|
||||
select cmp dl, [dsknum]
|
||||
je logfdd.ret
|
||||
; clear out current contents
|
||||
push dx
|
||||
|
|
@ -191,35 +219,42 @@ loghdd sub dl, 2
|
|||
logerr stc
|
||||
ret
|
||||
|
||||
; count from partition start
|
||||
; map sector into dskbuf
|
||||
; sector number from partition start
|
||||
; IN dx:ax sector number
|
||||
maprel add ax, [bpb+BPBHS]
|
||||
map add ax, [bpb+BPBHS]
|
||||
add dx, [bpb+BPBHS+2]
|
||||
; absolute sector count
|
||||
; skip doing a read if sector number matches
|
||||
; IN dx:ax sector number
|
||||
mapabs cmp ax, [dskseek]
|
||||
jne dskread
|
||||
jne l003
|
||||
cmp dx, [dskseek+2]
|
||||
jne dskread
|
||||
ret
|
||||
|
||||
dskread push ax
|
||||
je l002
|
||||
; flush and read other sector
|
||||
l003 push ax
|
||||
push dx
|
||||
call flush
|
||||
pop dx
|
||||
pop ax
|
||||
; store the sector number
|
||||
mov [cs:dskseek], ax
|
||||
mov [cs:dskseek+2], dx
|
||||
; do the actual read
|
||||
mov [dskseek], ax
|
||||
mov [dskseek+2], dx
|
||||
jmp _read
|
||||
|
||||
; mark dskbuf as containing unwritten changes
|
||||
dirty or byte [cs:dskflag], 1 ; dirty
|
||||
l002 ret
|
||||
|
||||
; flush buffer if dirty
|
||||
flush test byte [cs:dskflag], 1
|
||||
jz l002
|
||||
; low level read and write
|
||||
; call again to retry, no input registers
|
||||
; read or write is configured in cx
|
||||
_read mov ch, 2
|
||||
db 0x3D ; cmp ax, imm16: causes next instr to be skipped
|
||||
_write mov ch, 3
|
||||
db 0x3D ; cmp ax, imm16: causes next 2 bytes to be skipped
|
||||
_read mov ch, 2
|
||||
mov cl, 1 ; read len
|
||||
; DS := ES := CS
|
||||
mov ax, cs
|
||||
|
|
@ -286,14 +321,3 @@ _write mov ch, 3
|
|||
; exit with carry flag set
|
||||
stc
|
||||
ret
|
||||
|
||||
; mark dskbuf as containing unwritten changes
|
||||
dirty or byte [cs:dskflag], 1 ; dirty
|
||||
ret
|
||||
|
||||
; flush buffer if dirty
|
||||
flush test byte [cs:dskflag], 1
|
||||
jz .ret
|
||||
; TODO: error handling & retries
|
||||
jmp _write
|
||||
.ret ret
|
||||
|
|
|
|||
|
|
@ -0,0 +1,125 @@
|
|||
section .bss
|
||||
|
||||
clus resw 1
|
||||
|
||||
section .text
|
||||
|
||||
; Set cluster for next operations
|
||||
; IN dx cluster number
|
||||
setclus mov [clus], dx
|
||||
ret
|
||||
|
||||
; get ptr to single byte in fat table
|
||||
; IN dx position byte in fat table
|
||||
; OUT bx ptr to byte in dskbuf
|
||||
_fat1 push dx
|
||||
mov ax, dx
|
||||
xor dx, dx
|
||||
mov cl, 9
|
||||
shr ax, cl
|
||||
add ax, [bpb+BPBRSC]
|
||||
adc dx, 0
|
||||
call map
|
||||
pop dx
|
||||
mov bx, dx
|
||||
and bx, 0x1FF
|
||||
add bx, dskbuf
|
||||
ret
|
||||
|
||||
; get ptr to word in fat table
|
||||
_fat2 push dx
|
||||
mov ax, dx
|
||||
xor dx, dx
|
||||
mov cl, 8
|
||||
shr ax, cl
|
||||
add ax, [bpb+BPBRSC]
|
||||
adc dx, 0
|
||||
call map
|
||||
pop dx
|
||||
mov bl, dl
|
||||
mov bh, 0
|
||||
add bx, bx
|
||||
add bx, dskbuf
|
||||
ret
|
||||
|
||||
; read value from fat table
|
||||
; index given with setclus
|
||||
; OUT bx value
|
||||
; carry set if EOF marker
|
||||
rdfat mov dx, [clus]
|
||||
mov ax, dx
|
||||
shr ax, 1
|
||||
add dx, ax
|
||||
call _fat1
|
||||
push word [bx]
|
||||
inc dx
|
||||
call _fat1
|
||||
mov si, bx
|
||||
pop bx
|
||||
mov bh, [si]
|
||||
test word [clus], 1
|
||||
jz l001
|
||||
mov cl, 4
|
||||
shr bx, cl
|
||||
l001 and bx, 0xFFF
|
||||
cmp bx, 0xFF0
|
||||
cmc
|
||||
ret
|
||||
|
||||
; set value in FAT table
|
||||
; IN dx value
|
||||
wrfat and dh, 0x0F
|
||||
push dx
|
||||
; DX = index * 1.5
|
||||
mov dx, [clus]
|
||||
mov ax, dx
|
||||
shr dx, 1
|
||||
add dx, ax
|
||||
call _fat1
|
||||
pop ax
|
||||
test [clus], 1
|
||||
jnz l004
|
||||
; even, first byte full
|
||||
mov [bx], al
|
||||
push ax
|
||||
call dirty
|
||||
; DX = index * 1.5
|
||||
mov dx, [clus]
|
||||
mov ax, dx
|
||||
shr dx, 1
|
||||
add dx, ax
|
||||
inc dx
|
||||
call _fat1
|
||||
pop ax
|
||||
mov al, [bx]
|
||||
and al, 0xF0
|
||||
or al, ah
|
||||
mov [bx], al
|
||||
call dirty
|
||||
jmp l005
|
||||
; odd, second byte full
|
||||
l004: mov ch, [bx]
|
||||
; concat existing and our nib
|
||||
and ch, 0x0F
|
||||
mov cl, 4
|
||||
shl ax, cl
|
||||
or al, ch
|
||||
; write back lower 4 bits
|
||||
mov [bx], al
|
||||
call dirty
|
||||
push ax
|
||||
; re-calculate offset
|
||||
mov ax, dx
|
||||
shr dx, 1
|
||||
add dx, ax
|
||||
inc dx
|
||||
; map second byte
|
||||
call _fat1
|
||||
pop ax
|
||||
; write higher 8 bits
|
||||
mov [bx], ah
|
||||
call dirty
|
||||
l005: ret
|
||||
|
||||
; wrfat from above, FAT16 flavour
|
||||
wf16: ret
|
||||
|
|
@ -0,0 +1,8 @@
|
|||
org 0
|
||||
jmp init
|
||||
|
||||
init: mov ax, 0x0e37
|
||||
int 0x10
|
||||
|
||||
hlt: hlt
|
||||
jmp hlt
|
||||
Loading…
Reference in New Issue