I've been trying to get my driver (read-only) for floppies to work. Under bochs it does fine, yet under a real system it doesn't actually load any content (or at least not at the location it's supposed to load to). Are there maybe some assembly programmer's who can spot the mistake?
Code: Select all
FDD:
%define FD.STATUS_A 0x03F0 ;read
%define FD.STATUS_B 0x03F1 ;read
%define FD.DRIVE_CONTROL 0x03F2 ;DOR
%define FD.DRIVE_STATUS 0x03F3
%define FD.DRIVE_CONTROLLER_STATUS 0x03F4 ;read
%define FD.PRECOMP_SELECT 0x03F4 ;write
%define FD.FIFO 0x03F5
%define FD.DATARATE_STATUS 0x03F7 ;read
%define FD.DATARATA_CONTROL 0x03F7 ;write
%define FLOPPY.SECTOR 0x200
DMA:
.READFLOPPY:
;-------------------------------;
;DMA Initialization. ;
;IN: ;
; EBX: 24 bits address ;
;Hadrianius Ferrarius -- SCSS ;
; Development Project. ;
; SD: UNK - (2008) ;
;-------------------------------;
mov al,0x06 ;Mask DMA2
out 0x0A,al
mov al,0xFF ;Reset Master FlipFlop
out 0xD8,al
mov eax,ebx ;Get Address
out 0x04,al
shr eax,0x08 ;High Byte
out 0x04,al
mov al,0xFF ;Reset Master FlipFlop
out 0xD8,al
mov ebx,eax ;save address part
mov eax,0x3FF ;Count
out 0x05,al
shr eax,0x08 ;count
out 0x05,al
mov al,0x46 ;mode
out 0x0B,al
mov eax,ebx ;Retrieve Address Part
shr eax,0x08 ;Page Address
out 0x81,al
mov al,0x02
out 0x0a,al
ret
.WRITEFLOPPY:
;-------------------------------;
;DMA setup for Floppy Write ;
;Hadrianius Ferrarius -- SCSS ;
; Development Project. ;
; SD: UNK - (2008) ;
;-------------------------------;
mov al,0x06 ;DMA channel 2 Mask
out 0x0A,al ;Mask the Bastard
mov al,0x4a ;Single Transfer, From Mem, CH2
out 0x0a,al ;output to port
mov al,0x02
out 0x0a,al ;unmask the bastard
ret ;return to calling procedure
;Now here comes the good stuff;
FLOPPY:
;-------------------------------;
;Clears Interrupt Flag in the ;
; Status Register Once Arrived ;
;Hadrianius Ferrarius -- SCSS ;
; Development Project. ;
; SD: UNK - (2008) ;
;-------------------------------;
.INT:
mov al,[FINT]
cmp al,0xFF
jne .INT
;call .RECEIVED
;call .RECEIVED
xor al,al
mov [FINT],al
ret
.SNI:
push ax
push dx
mov ax,FD.FIFO
mov dx,ax
mov al,0x08
call .CHREADY
out dx,al
mov al,'Z'
call [0x20028]
call .RECEIVED
call .RECEIVED
mov al,'{'
call [0x20028]
pop dx
pop ax
ret
.SMM:
push ax
push dx
mov ax,FD.FIFO
mov dx,ax
mov al,0x08
call .CHREADY
out dx,al
mov al,'Z'
call [0x20028]
;call .RECEIVED
;call .RECEIVED
mov al,'{'
call [0x20028]
pop dx
pop ax
ret
.GET:
call .RECEIVED
call .RECEIVED
ret
.RNS:
mov al,[FINT]
cmp al,0xFF
jne .RNS
ret
.FINISH:
mov ax,FD.FIFO
mov dx,ax
mov al,0x08
call .CHREADY
out dx,al
mov al,'Z'
call [0x20028]
xor al,al
mov [FINT],al
ret
;-------------------------------;
;Checks to see if FIFO can be ;
; Written to. ;
; With Great Thanks to the ;
; DynatOS Team. Please Read The ;
; License Agreement Within This ;
; File ;
;-------------------------------;
.CHREADY:
push eax
push edx
mov dx,FD.DRIVE_CONTROLLER_STATUS
.CH:
in al,dx
and al,0xC0
cmp al,0x80
jne .CH
pop edx
pop eax
ret
;-------------------------------;
;Takes Information from FIFO ;
; With Great Thanks to the ;
; DynatOS Team. Please Read The ;
; License Agreement Within This ;
; File ;
;-------------------------------;
.RECEIVED:
push eax
push edx
mov al,'>'
call [0x20028]
mov dx,FD.DRIVE_CONTROLLER_STATUS
.RC:
;in al,dx
;and al,0xC0
;cmp al,0xC0
mov al,0x10
call [0x20028]
;jne .RC
mov dx,FD.FIFO
in al,dx
call [0x20028]
mov al,'?'
call [0x20028]
mov al,0
call [0x20028]
pop edx
pop eax
ret
.ON:
;-------------------------------;
;FD Motor Startup. Uses Basic ;
; Timer to wait for startup ;
; times. ;
;Hadrianius Ferrarius -- SCSS ;
; Development Project. ;
; SD: UNK - (2008) ;
;-------------------------------;
push eax
push edx
mov ax,FD.DRIVE_CONTROL ;Ax gets Port Address
mov dx,ax ;Port Address
mov al,00011100b
out dx,al ;Value to be set: 00011100
; - Motor is now spinning up -;
mov al,'N'
call [0x20028]
mov al,0x05
call .WAIT
pop edx
pop eax
ret
.OFF:
;-------------------------------;
;FD Motor Startup. Uses Basic ;
; Timer to wait for startup ;
; times. ;
;Hadrianius Ferrarius -- SCSS ;
; Development Project. ;
; SD: UNK - (2008) ;
;-------------------------------;
push eax
push edx
mov ax,FD.DRIVE_CONTROL ;Ax gets Port Address
mov dx,ax ;Port Address
mov al,0x0c
out dx,al
mov al,'F'
call [0x20028]
pop edx
pop eax
ret
.RECALIBRATE:
;-------------------------------;
;Recalibrates Disc System ;
;Hadrianius Ferrarius -- SCSS ;
; Development Project. ;
; SD: UNK - (2008) ;
;-------------------------------;
push eax
push edx
mov al,'E'
call [0x20028]
mov ax,FD.FIFO ;ax gets port address
mov dx,ax ;dx gets port address
mov al,0x07 ;command for recalibration of drive
call .CHREADY
out dx,al ;sending command.
mov al,'-'
call [0x20028]
xor al,al ;drive zero to be calibrated
out dx,al
call .SNI
call .INT
mov al,'R'
call [0x20028]
pop edx
pop eax
ret
.SEEK:
;-------------------------------;
;Seeks to cylinder. For v0.03 ;
; MIK only assumes first ;
; Cylinder. ;
;Hadrianius Ferrarius -- SCSS ;
; Development Project. ;
; SD: UNK - (2008) ;
;-------------------------------;
push eax
push edx
mov al,']'
call [0x20028]
mov ax,FD.FIFO ;ax gets port address
mov dx,ax ;dx get port address
mov al,0x0F ;Command for Seek function
call .CHREADY
out dx,al ;output to port
mov al,'['
call [0x20028]
xor al,al ;clearing al
out dx,al ;Drive 0, Head 0
; - Put cylinder assignment here - ;
out dx,al ;Cylinder Zero
call .SMM
call .GET
mov al,'S'
call [0x20028]
mov byte[FINT],0x00
pop edx
pop eax
ret
.READ:
;-------------------------------;
;Reads one sector as specified ;
; in CHS of the disk. For v0.03 ;
; only 18 sectors can be sent. ;
; IN: ;
; bl: Sector Number ;
;Hadrianius Ferrarius -- SCSS ;
; Development Project. ;
; SD: UNK - (2008) ;
;-------------------------------;
push eax
push ebx
push ecx
push edx
mov al,'|'
call [0x20028]
mov dx,FD.FIFO ;Port Address
call .CHREADY ;Check if FIFO is ready
mov al,'9'
call [0x20028]
mov al,0x46 ;Read Sector Command
out dx,al
mov al,0x00 ;Disk 0
out dx,al
out dx,al ;Cylinder
out dx,al ;Head
mov al,0x07 ;Sector Number
out dx,al
mov al,0x02 ;Sector = 512 bytes
out dx,al ;SectorSize
mov al,0x07
inc al
;mov al,0x12
out dx,al ;Last Sector Of Track
mov al,0x1B
out dx,al ;Gap Length
mov al,0xFF
call [0x20028]
out dx,al ;Obsolete Hardware Requirement
call .RNS
mov ecx,0x07
.READFIN:
call .RECEIVED
loop .READFIN
CALL .FINISH
call .RECEIVED
call .RECEIVED
mov al,'M'
call [0x20028]
pop edx
pop ecx
pop ebx
pop eax
ret
.WAIT:
;-------------------------------;
;Waits for a specified amount ;
; of time (multiples of ~55mS ;
; IN: ;
; al: 55*al ;
;Hadrianius Ferrarius -- SCSS ;
; Development Project. ;
; SD: UNK - (2008) ;
;-------------------------------;
call .WINIT ;Enable Floppytimer
.WAITLOOP:
mov bl,[FLOPPYTIMER] ;Get value of timer
cmp al,bl ;Is time past?
jae .WAITLOOP ;Nope
call .WSTOP ;Yep
mov al,'W'
call [0x20028]
ret
.WINIT:
;-------------------------------;
;Initiates Timer ;
;Hadrianius Ferrarius -- SCSS ;
; Development Project. ;
; SD: UNK - (2008) ;
;-------------------------------;
mov bl,[TIMERCENTER] ;Current settings of Timers
or bl,0x01 ;Set Floppytimer Bit
mov [TIMERCENTER],bl ;Enable Timer
ret
.WSTOP:
;-------------------------------;
;Stops Timer ;
;Hadrianius Ferrarius -- SCSS ;
; Development Project. ;
; SD: UNK - (2008) ;
;-------------------------------;
mov bl,[TIMERCENTER] ;Current settings of Timers
or bl,0x01 ;Make it one,
xor bl,0x01 ;Clear the bit
mov [TIMERCENTER],bl ;Stop timer
xor bl,bl
mov [FLOPPYTIMER],bl ;Clear Floppytimer
ret
FINT db 0
;---------------------------------------------------------------;
; 1 Copyright (c) 2007 The DynatOS Project. ;
; 2
; 3 Permission is hereby granted, free of charge, to any person obtaining a copy of
; 4 this software and associated documentation files (the "Software"), to deal in
; 5 the Software without restriction, including without limitation the rights to
; 6 use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
; 7 the Software, and to permit persons to whom the Software is furnished to do so,
; 8 provided that the above copyright notice and this permission notice is included
; 9 in all copies or substantial portions of the Software.
; 10
; 11 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
; 12 IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
; 13 FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
; 14 COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
; 15 IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
; 16 CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
; 17
; 18 The views, opinions and conclusions contained in the software and documentation
; 19 are those of the authors and should not be interpreted as representing official
; 20 policies, either expressed or implied, of The DynatOS Project.
;---------------------------------------------------------------;
