; ***************************************************************************** ; ; DISK_IO.ASM [ TRDOS Kernel Disk IO (Read, Write) Procedures ] ; Copyright (C) 2009-2010 Erdogan TAN [20/07/2011] ; ; 19/06/2011, 03/07/2011, 05/07/2011, 06/07/2011 ; 01/05/2010, 16/05/2010, 17/05/2010, 17/10/2010, 05/12/2010 ; 28/02/2010, 18/04/2010, 21/04/2010, 24/04/2010 ; 24/09/2009, 04/07/2009 ; ; TRDOS.ASM (include disk_io.asm) ; ; ***************************************************************************** proc_CHS_read proc near ; 20/07/2011 ; 06/07/2011 ; 05/07/2011 ; 19/06/2011 ; 05/12/2010 ; 17/05/2010 DX:AX at return -> Next LBA Adress ; 18/04/2010 ES:BX -> Segment limit check ; 04/07/2009 ; ; INPUT -> DX:AX = Logical Block Address ; CX = Number of sectors to read ; DS:SI = Logical Dos Disk Table Offset (DRV) ; ES:BX = Destination Buffer ; OUTPUT -> clc or stc ; loc_read_disk_chs_reset_rc: ; 05/12/2010 mov byte ptr [CHS_RetryCount], 4 loc_read_disk_chs: push DX ; DX_AX = Linear address (sectors) push AX ; Linear sector # push CX ; # of FAT/FILE/DIR sectors mov CX,Word Ptr [SI][LD_BPB][SecPerTrack] push BX call RX_DOS_DIV32 ; Special 32 bit divide !!! ; To fix large disk problem. ; (c) Erdogan Tan 1999 ; (October 20th, 1999) mov CX, BX ; Sector (zero based) inc CX ; To make it 1 based push CX mov CX,Word Ptr [SI][LD_BPB][Heads] call RX_DOS_DIV32 ; Convert track to head & cyl mov DH, BL ; BX = Head (max. FFh) pop CX ; AX=Cyl, DH=Head, CX=Sector pop BX ; ES:BX = Buffer mov DL,Byte Ptr [SI][LD_PhyDrvNo] mov CH,AL ror AH,1 ; Rotate right ror AH,1 or CL,AH mov AX,0201h int 13h ; BIOS Service func ( ah ) = 2 ; Read disk sectors ; AL-sec num CH-track CL-sec ; DH-head DL-drive ES:BX-buffer ; CF-flag AH-stat AL-sec read ; If CF = 1 then (If AH > 0) ; 19/06/2011 mov byte ptr [Disk_IO_err_Code], AH pop CX pop AX pop DX jnc short loc_read_disk_chs_no_error ; 05/07/2011 cmp byte ptr [Disk_IO_err_code], 09h ; DMA crossed 64K segment boundary je short loc_read_disk_chs_error_retn ; 06/07/2011 ; ; 20/07/2011 dec byte ptr [CHS_RetryCount] jnz short loc_read_disk_chs loc_read_disk_chs_error_retn: ; 20/07/2011 ; 06/07/2011 stc retn loc_read_next_sector: add BX, 512 ; 18/04/2010 jnc short loc_read_disk_chs_reset_rc ; 03/07/2011 push BX mov BX, ES add BX, 1000h mov ES, BX pop BX ; jmp short loc_read_disk_chs_reset_rc ; 05/12/2010 loc_read_disk_chs_no_error: ; 17/05/2010 DX:AX retn -> next LBA address add AX,1 adc DX,0 ; loop loc_read_next_sector retn proc_CHS_read endp proc_LBA_read proc near ; 20/07/2011 ; 19/06/2011 ; 01/05/2010 ; 04/07/2009 ; 2005 ; INPUT -> DAP_Buffer ; OUTPUT -> clc or stc ; cx = number of blocks read loc_read_disk_lba: push si mov si, offset DAP_Buffer loc_read_disk_lba_again: ; DS:SI= DAP Location mov ah, 42h ; Extended Disk Read - LBA Read ;mov dl, byte ptr [DAP_BuffDisk] int 13h mov byte ptr [Disk_IO_err_Code], ah ; 19/06/2011 jnc short pass_read_disk_lba_error dec byte ptr [DAP_RetryCount] ; 20/07/2011 jnz short loc_read_disk_lba_again ;xor ch, ch mov cl, byte ptr [DAP_BuffNumOfBlocks] stc pass_read_disk_lba_error: pop si retn proc_LBA_read endp proc_disk_read proc near ; 17/10/2010 LBA bugfix ; 16/05/2010 read error -> 1Eh retn ; 01/05/2010 ; 24/04/2010 sector count bugfix ; 21/04/2010 ES:BX bugfix ; 18/04/2010 ; -> read all lba sectors even if cx > 127 ; 04/07/2009 ; INPUT -> DS:SI = DOS Drive Description Table ; INPUT -> DX:AX = LBA address ; INPUT -> CX = Sector Count (CH=0) ; INPUT/OUTPUT -> ES:BX = Buffer ; OUTPUT -> DX:AX = Next LBA address ; OUTPUT -> stc -> Error code in AL (AX) ; OUTPUT -> CX = Sector count (loaded to buffer) ; ; 24/04/2010, 18/04/2010 mov word ptr [Disk_RW_SectorCount], cx ;21/04/2010 push es push bx ;01/05/2010 push cx ; cmp byte ptr [SI][LD_LBAYes], 0 ja short loc_read_lba_sectors loc_read_chs_sectors: call proc_chs_read jc short retn_read_sectors_stc ;01/05/2010 or cx, cx jz short retn_read_sectors retn_read_sectors_stc: ; 01/05/2010 pop ax ; pushed cx sub ax, cx ; cx = remain sectors to read mov cx, ax stc ; 16/05/2010 ; mov ax, 1Eh ; Drive not ready or read error ! ;01/05/2010 ;jmp short retn_read_sectors_pop_bx_pop_es push cx retn_read_sectors: ; 01/05/2010 pop cx retn_read_sectors_pop_bx_pop_es: ; 21/04/2010 pop bx pop es ; retn loc_read_lba_sectors: ; 18/04/2010 cmp cx, 127 jna short pass_read_lba_sectors_count_fix mov cx, 127 pass_read_lba_sectors_count_fix: ; mov byte ptr [DAP_BuffLBAyes], 1 mov word ptr [DAP_BuffLBA_Address], ax mov word ptr [DAP_BuffLBA_Address]+2, dx mov byte ptr [DAP_BuffPacketSize], 10h mov word ptr [DAP_BuffDestination], bx push es pop word ptr [DAP_BuffDestination]+2 mov byte ptr [DAP_BuffNumOfBlocks], cl mov byte ptr [DAP_RetryCount], 4 ; 17/10/2010 BugFix push ax push dx mov dl, byte ptr [SI][LD_PhyDrvNo] mov byte ptr [DAP_BuffDisk], dl call proc_lba_read ; 17/10/2010 pop dx pop ax jc short retn_lba_read_sectors_stc ; 18/04/2010 add ax, cx ; cx <= 127 adc dx, 0 push dx push ax mov ax, 512 mul cx add bx, ax jnc short pass_read_disk_lba_next_segment mov dx, es add dx, 1000h mov es, dx pass_read_disk_lba_next_segment: pop ax pop dx cmp cx, word ptr [Disk_RW_SectorCount] jnb short retn_read_sectors sub word ptr [Disk_RW_SectorCount], cx mov cx, word ptr [Disk_RW_SectorCount] jmp short loc_read_lba_sectors retn_lba_read_sectors_stc: ;01/05/2010 sub word ptr [Disk_RW_SectorCount], cx mov cx, word ptr [Disk_RW_SectorCount] jmp short retn_read_sectors_stc proc_disk_read endp proc_disk_write proc near ; 17/10/2010 LBA bugfix ; 01/05/2010 ; 24/04/2010 sector count bugfix ; 21/04/2010 ES:BX bugfix ; 18/04/2010 ; 09/02/2005 ; INPUT -> DS:SI = DOS Drive Description Table ; INPUT -> DX:AX = LBA address ; INPUT -> CX = Sector Count (CH=0) ; INPUT/OUTPUT -> ES:BX = Buffer ; OUTPUT -> DX:AX = Next LBA address ; OUTPUT -> stc -> Error code in AL (AX) ; OUTPUT -> CX = Sector count (written to disk) ; ;24/04/2010, 18/04/2010 mov word ptr [Disk_RW_SectorCount], cx ;21/04/2010 push es push bx ;01/05/2010 push cx ; cmp byte ptr [SI][LD_LBAYes], 0 ja short loc_write_lba_sectors call proc_CHS_write jc short retn_write_sectors_stc ;01/05/2010 or cx, cx jz short retn_write_sectors retn_write_sectors_stc: ; 01/05/2010 pop ax ; pushed cx sub ax, cx ; cx = remain sectors to write mov cx, ax stc ; 18/04/2010 ; mov ax, 1Dh ; Drive not ready or write error ! ;01/05/2010 ;jmp short retn_write_sectors_pop_bx_pop_es push cx retn_write_sectors: ; 01/05/2010 pop cx retn_write_sectors_pop_bx_pop_es: ; 21/04/2010 pop bx pop es ; retn loc_write_lba_sectors: ; 18/04/2010 cmp cx, 127 jna short pass_write_lba_sectors_count_fix mov cx, 127 pass_write_lba_sectors_count_fix: ;mov byte ptr [DAP_BuffLBAyes], 1 mov word ptr [DAP_BuffLBA_Address], ax mov word ptr [DAP_BuffLBA_Address]+2, dx mov byte ptr [DAP_BuffPacketSize], 10h mov word ptr [DAP_BuffDestination], bx push es pop word ptr [DAP_BuffDestination]+2 mov byte ptr [DAP_BuffNumOfBlocks], cl mov byte ptr [DAP_RetryCount], 4 ; 17/10/2010 BugFix push ax push dx mov dl, byte ptr [SI][LD_PhyDrvNo] mov byte ptr [DAP_BuffDisk], dl call proc_LBA_write ; 17/10/2010 pop dx pop ax jc short retn_lba_write_sectors_stc ; 18/04/2010 add ax, cx ; cx <= 127 adc dx, 0 push dx push ax mov ax, 512 mul cx add bx, ax jnc short pass_write_disk_lba_next_segment mov dx, es add dx, 1000h mov es, dx pass_write_disk_lba_next_segment: pop ax pop dx cmp cx, word ptr [Disk_RW_SectorCount] jnb short retn_write_sectors sub word ptr [Disk_RW_SectorCount], cx mov cx, word ptr [Disk_RW_SectorCount] jmp short loc_write_lba_sectors retn_lba_write_sectors_stc: ;01/05/2010 sub word ptr [Disk_RW_SectorCount], cx mov cx, word ptr [Disk_RW_SectorCount] jmp short retn_write_sectors_stc proc_disk_write endp proc_CHS_write proc near ; 20/07/2011 ; 09/07/2011 ; 20/06/2011 ; 19/06/2011 ; 05/12/2010 ; 17/05/2010 DX:AX at return -> Next LBA Adress ; 01/05/2010 ; 18/04/2010 ; 09/02/2005 ; INPUT -> DX:AX = Logical Block Address ; CX = Number of sectors to read ; DS:SI = Logical Dos Disk Table Offset (DRV) ; ES:BX = Source Buffer ; OUTPUT -> clc or stc ; loc_write_disk_chs_reset_rc: ; 05/12/2010 mov byte ptr [CHS_RetryCount], 4 loc_write_disk_chs: push DX ; DX_AX = Linear address (sectors) push AX ; Linear sector # push CX ; # of FAT/FILE/DIR sectors mov CX,Word Ptr [SI][LD_BPB][SecPerTrack] push BX call RX_DOS_DIV32 ; Special 32 bit divide !!! ; To fix large disk problem. ; (c) Erdogan Tan 1999 ; (October 20th, 1999) mov CX, BX ; Sector (zero based) inc CX ; To make it 1 based push CX mov CX,Word Ptr [SI][LD_BPB][Heads] call RX_DOS_DIV32 ; Convert track to head & cyl mov DH, BL ; BX = Head (max. FFh) pop CX ; AX=Cyl, DH=Head, CX=Sector pop BX ; ES:BX = Buffer mov DL,Byte Ptr [SI][LD_PhyDrvNo] mov CH,AL ror AH,1 ; Rotate right ror AH,1 or CL,AH mov AX,0301h int 13h ; BIOS Service func ( ah ) = 3 ; Write disk sectors ;AL-sec num CH-track CL-sec ; DH-head DL-drive ES:BX-buffer ;CF-flag AH-stat AL-sec read ; If CF = 1 then (If AH > 0) ; 19/06/2011 mov byte ptr [Disk_IO_err_Code], ah pop CX pop AX pop DX jnc short loc_write_disk_chs_no_error ; 20/07/2011 dec byte ptr [CHS_RetryCount] jnz short short loc_write_disk_chs loc_write_disk_chs_error_retn: ; 20/07/2011 stc retn loc_write_next_sector: add BX, 512 ; 18/04/2010 jnc short loc_write_disk_chs_reset_rc ; 03/07/2011 push BX mov BX, ES add BX, 1000h mov ES, BX pop BX ; jmp short loc_write_disk_chs_reset_rc ; 05/12/2010 loc_write_disk_chs_no_error: ; 17/05/2010 DX:AX retn -> next LBA address add AX,1 adc DX,0 loop loc_write_next_sector retn proc_CHS_write endp proc_LBA_write proc near ; 20/07/2011 ; 19/06/2011 ; 01/05/2010 ; 09/02/2005 ; INPUT -> DAP_Buffer ; OUTPUT -> clc or stc ; cx = number of blocks written loc_write_disk_lba: push si mov si, offset DAP_Buffer loc_write_disk_lba_again: ; DS:SI= DAP Location mov ax, 4300h ; Extended Disk Write - LBA write (verify off) ;mov dl, byte ptr [DAP_BuffDisk] int 13h mov byte ptr [Disk_IO_err_Code], ah ; 19/06/2011 jnc short pass_write_disk_lba_error dec byte ptr [DAP_RetryCount] ;20/07/2011 jnz short loc_write_disk_lba_again ;xor ch, ch mov cl, byte ptr [DAP_BuffNumOfBlocks] stc pass_write_disk_lba_error: pop si retn proc_LBA_write endp ; 24/04/2010, 18/04/2010 Disk_RW_SectorCount: dw 0 ; CHS_RetryCount: db 0 ; 19/06/2011 Disk_IO_err_Code: db 0 ; Disk Read Procedure Parameters DAP_RetryCount: db 4 DAP_BuffCDRV_BPB: dw 0 DAP_BuffDisk: db 0 DAP_BuffLBAyes: db 0 DAP_Buffer: DAP_BuffPacketSize: db 0 DAP_BuffReservd1: db 0 DAP_BuffNumOfBlocks: db 0 DAP_BuffReservd2: db 0 DAP_BuffDestination: dd 0 DAP_BuffLBA_Address: dd 0 DAP_BuffLBA_Addressq: dd 0