ProfitPress Mega CDROM2 Shareware Freeware (MSDOS)(1992)(Eng)

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Assembly Source File | 1991-11-25 | 25.3 KB | 1,042 lines

NAME Device_Driver_Installer TITLE Idrv.asm ;::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::; ; 18-11-1991 ; ; Idrv.asm (v1.06) ; ; compiled with Turbo Assembler v1.0 ; ; by Janusz Wojcik ; ; Lublin,Poland. ; ;..............................................................................; ASSUME DS:st_seg, SS:st_seg ,CS:st_seg ,ES:st_seg st_seg SEGMENT ORG 100h start: mov ax,es dec ax mov es,ax ;ES = ES - 1 mov ax,word ptr es:3 ;get size of memory block from MCB push ax mov bx,es add ax,bx ;compute address of the end of memory block mov bx,LEN + 15 ;compute size of the program ... mov cl,4 shr bx,cl ; ... in paragraphs sub ax,bx ;calculate new address of program's beginning mov jmp_seg,ax ;save it mov es,ax ;....................................................... pop ax mov dx,10h ;add PSP size add dx,bx sub ax,dx cmp ax,1000h ;some drivers set stack at the ... ; ... end of the segment !!! ja move_code ;jump if more than 64KB left lea dx,too_small mov ah,9 int 21h mov ah,4ch ;EXIT mov al,1 ;Set return code int 21h ;....................................................... move_code: mov cx,LEN mov di,0 mov si,offset pr_end cld rep movsb ;move program into upper memory jmp dword ptr jmp_offs ;and go there too_small db 'IDrv: Too small memory!',cr,lf,lf,'$' jmp_offs dw 0 jmp_seg dw 0 ALIGN 16 pr_end equ $ st_seg ends ;******************************************************************************* ASSUME DS:code, SS:code ,CS:code ,ES:code code SEGMENT Byte Public 'code' new_seg equ $ mov ax,cs cli mov ss,ax ;Set own stack mov sp,offset EOS sti mov ax,ds push cs pop ds ;DS = CS mov our_seg,ax jmp starter ; jump over data own_stack db 157 dup(0) EOS equ $ ; End Of Stack ;............................................................................... device_header struc next_offs dw ? next_seg dw ? dev_attr dw ? dev_strategy dw ? dev_interrupt dw ? name_unit db 8 dup(?) device_header ends ;Idrv Control Block icb struc signature db 7 dup(?) xms_marker db 3 dup(?) prv_xms_offs dw ? prv_xms_seg dw ? xms_handle dw ? icb ends .errnz 16 - SIZE icb ;............................................................................... lf equ 0ah ; line feed cr equ 0dh ; carriage return ZERO equ 0 INIT equ 0 TAB equ 9 DIB_SIZE equ 21h FIRST_DIB equ 26h FIRST_DA equ 3ch NUM_OF_DRV equ 46h TOTAL_NUM equ 47h MAX_SECTOR equ 36h JMP_SHORT equ 3ebh JMP_FAR equ 0eah ;............................................................................... ; the program body ;.............................................................................. ldrv: call load_drv jnc idev jmp exit idev: mov es,dos_seg mov al,byte ptr es:NUM_OF_DRV ;Get real number of drives mov drive_num,al ;Set unit number in Req. Header call init_dev ;INIT device jnc modify_mem call restore_xms ;restore previous state of original XMS handler lea dx,err3 jmp exit modify_mem: call restore_xms ;restore previous state of original XMS handler test flags,UMB_USED ;Driver in other mem. block ? jz create_cb ;No,skip mov bx,ending_offset add bx,15 rcr bx,1 mov cl,3 shr bx,cl add bx,ending_segment mov ax,dev_seg dec ax ;take into account ICB size! sub bx,ax ;BX - size of mem. block in paragraphs mov es,ax ;ES - seg. of the block mov ah,4ah ;Modify alloc. mem. block int 21h jnc create_cb lea dx,err7 jmp exit_err create_cb: mov ax,dev_seg mov es,ax mov bx,drv_beg call create_icb ;create Idrv Control Block mov ax,es:dev_attr[bx] test ah,80h ;Character device ? jnz ldev ;Yes,jump to link device headers cmp units,ZERO ;Error during INIT ? jnz check_CDS ;No lea dx,err3 jmp exit ;Yes,jump to quit check_CDS: call check_DA jc exit_err DIB_creation: call seek_last ;Seek the last DIB mov lastDIB_offs,bx mov lastDIB_seg,es test flags,UMB_USED ;driver in other mem.block ? jz DIB_after_drv ;No,jump mov ax,our_seg add ax,10h ;add PSP size jmp set_DIB_addr DIB_after_drv: mov ax,ending_offset add ax,15 mov cl,4 shr ax,cl add ax,ending_segment set_DIB_addr: mov DIB_seg,ax mov DIB_offs,ZERO mov cl,units ;CX = number of units xor ch,ch mov dl,es:[bx] ;DL = last drive# mov dh,0ffh DIB_continue: inc dl ;Set drive# inc dh ;Set unit# call create_DIB ;Create Disk Info Block jnc DA_creation call restore ;Restore previous state of DIB & DA chains jmp exit_err DA_creation: call create_DA ;Create Disk Area les bx,dword ptr DIB_offs add DIB_offs,DIB_SIZE ;Set new DIB address loop DIB_continue ldev: call link_dev ;Link device headers jmp exit_OK exit_err: call free_xmem call print_msg exit_OK: mov ax,our_seg mov es,ax mov es,es:2ch mov ah,49h ; Free allocated memory (environment) int 21h test flags,UMB_USED ; Driver in UMB ? jz drv_not_high ; No,jump mov dx,100h ; size of PSP add dx,ad_mem add dx,15 rcr dx,1 mov cl,3 shr dx,cl jmp term_resident drv_not_high: mov dx,ending_offset ;Compute address of ... add dx,ad_mem add dx,15 rcr dx,1 mov cl,3 shr dx,cl add dx,ending_segment inc dx ; (add one para) mov ax,our_seg sub dx,ax ; ... program end term_resident: xor al,al ; set 0 for return code mov ah,31h ;Terminate and remain resident int 21h exit: call print_msg exit_no_print: mov ah,4ch ;EXIT mov al,1 ;Set return code int 21h ;.............................................................................. ; create_icb: ; creates Idrv Control Block before Device Header ; Input: ; ES:BX - Device Header address ;.............................................................................. create_icb proc near push es mov ax,es dec ax mov es,ax mov si,offset sign mov cx,SIG_LEN mov di,bx cld rep movsb ;place signature mov ax,handle mov word ptr es:xms_marker[bx],ax ;the word will be ... ; ... 0 if handle is 0 cmp ax,ZERO je xms_not_used mov word ptr es:xms_handle[bx],ax mov byte ptr es:xms_marker[bx],'X' ;signal that XMS was used mov word ptr es:xms_marker[bx + 1],'SM' mov ax,prv_offs mov word ptr es:prv_xms_offs[bx],ax mov ax,prv_seg mov word ptr es:prv_xms_seg[bx],ax xms_not_used: pop es ret create_icb endp page;.......................................................................... ; link_dev: ....... ; links Device Header of the driver with the chain of ....... ; Device Headers of the rest drivers ....... ....... ;.............................................................................. link_dev: mov es,dos_seg mov si,48h push es les si,dword ptr es:[si] ;Address of next dev. header mov bx,drv_beg mov ax,dev_seg push ds mov ds,ax mov next_offs[bx],si mov next_seg[bx],es mov bx,dev_attr[bx] ;get dev.attribute for later pop ds pop es cli mov es:48h,word ptr ZERO mov ax,dev_seg mov es:4ah,ax sti test bl,1 ;Is it Stdin device ? jz test_clk ;No,jump mov es:32h,word ptr ZERO ;Change pointer to ... mov es:34h,ax ; ... Stdin les bx,es:02ah ;Get address of DOS file table add bx,dos_dep ;change entry length of OFT if necessary mov es:[bx + 042h],word ptr ZERO ;Change address of dev.header ... mov es:[bx + 044h],ax ; ... in Open Files Table jmp quit_link test_clk: test bl,8 ;Is it clock device ? jz quit_link ;No,jump mov es:2eh,word ptr ZERO mov es:30h,ax quit_link: ret ;.............................................................................. ; load_drv: ....... ; loads device driver code into memory ....... ;.............................................................................. load_drv: call get_file_len jc quit_load call alloc_umb mov ax,dev_seg xor dx,dx push ds mov ds,ax ;DS:DX - buffer address mov ah,3fh ;READ int 21h pop ds lea dx,err12 jc quit_load mov ah,3eh ;CLOSE int 21h quit_load: ret ;............................................................................... ; get_file_len: ; checks file length. ; OUTPUT: ; BX - file handle ; CX - file length ;............................................................................... get_file_len proc near mov ah,3dh ;OPEN mov dx,offset fname mov al,0 int 21h lea dx,err10 jc quit_get mov bx,ax ;save file handle mov ah,42h ;LSEEK ... mov al,2 ; ... to the end of file mov cx,ZERO mov dx,ZERO int 21h jnc get_cont1 lea dx,err11 jmp quit_get get_cont1: or dx,dx ;DX:AX - file length jz get_cont2 stc lea dx,err13 jmp quit_get get_cont2: push ax mov ah,42h ;LSEEK ... mov al,0 ; ... to the beginning xor cx,cx xor dx,dx int 21h lea dx,err11 pop cx quit_get: ret get_file_len endp ;............................................................................... ; alloc_umb: ; allocates Upper Memory Block if necessary ; INPUT: ; CX - file size in bytes ;............................................................................... alloc_umb: test flags,DOS_V5 ;DOS v5.xx and load high ? jz alloc_end ;No,jump test flags,LOAD_HIGH jz alloc_end ;No,jump push bx push cx ;save size of the file mov ax,5800h ;get memory allocation flags int 21h mov mem_flag,al ;save flags mov ax,5802h ;get link status int 21h mov link_stat,al mov ax,5801h ;search upper mem. for first fit mov bx,80h int 21h mov ax,5803h ;set link status mov bx,1 int 21h jc restore_alloc_flag mov bx,cx ;BX = file size add bx,0fh rcr bx,1 mov cx,3 shr bx,cl ;BX = size of mem. in paragraphs inc bx ;add one paragraph for ICB mov ah,48h ;allocate memory int 21h jc restore_alloc_flag inc ax ;driver will be placed after ICB mov dev_seg,ax or flags,UMB_USED ;driver is in other mem. block restore_alloc_flag: xor bh,bh mov bl,mem_flag mov ax,5801h ;restore allocation flags int 21h mov ax,5803h ;restore link status xor bh,bh mov bl,link_stat int 21h pop cx pop bx alloc_end: ret ;............................................................................... ; init_dev: ; calls Strategy and Interrupt Routines of the device driver ;............................................................................... init_dev: mov si,drv_beg mov ax,dev_seg mov es,ax mov ax,es:dev_strategy[si] ;get addr. of strategy routine mov dev_offs,ax mov ax,es:dev_interrupt[si] ;get addr. of interrupt routine push ax ;save it for later push cs pop es ;ES = CS mov bx,offset Request_Header ;ES:BX - Request Header call dword ptr dev_offs ;Call dev. strategy routine pop ax mov dev_offs,ax call dword ptr dev_offs ;Call dev. interrupt routine mov ax,ending_offset or ax,ax jnz quit_init mov ax,ending_segment cmp ax,dev_seg ja quit_init stc ret quit_init: clc ret ;............................................................................... ; print_msg: ; displays the message. ; INPUT: ; DS:DX - pointer to the character string ;............................................................................... print_msg: mov ah,9 int 21h ret ;............................................................................... ; seek_last: ; seeks the last Disk Info Block ; OUTPUT: ; ES:BX - last DIB ;............................................................................... seek_last proc near mov es,dos_seg les bx,es:FIRST_DIB ;Get address of first DIB mov si,dos_dep3 next_DIB: cmp word ptr es:[si + bx + 18h],0ffffh ;The last DIB ? jz seek_end ;Yes,jump les bx,dword ptr es:[si + bx + 18h] ;Get addr. of next DIB jmp next_DIB seek_end: ret seek_last endp ;................................................................................ ; create_DIB: ; creates Disk Info Block for the drive ; INPUT: ; ES:BX - last DIB ; DL - drive# ; DH - unit# ; ; OUTPUT: ; ES:BX - address of created DIB ;................................................................................ create_DIB proc near push ds mov ax,DIB_offs mov si,dos_dep3 mov word ptr es:[si + bx + 18h],ax ;Chain ... mov ax,DIB_seg ; ... mov word ptr es:[si + bx + 1ah],ax ; ... DIBs les bp,dword ptr DIB_offs ;ES:BP - next DIB address mov word ptr es:[bp],dx ;Set drive and unit # mov word ptr es:[si + bp + 18h],0ffffh ;Mark it as the last DIB mov byte ptr es:[si + bp + 17h],0ffh ;Init access flag mov word ptr es:[si + bp + 12h],ZERO ;Set address of ... mov ax,dev_seg mov word ptr es:[si + bp + 14h],ax ; ... device header lds si,dword ptr args_offset ;DS:SI = pointer to BPB push ax mov al,dh xor ah,ah mul cs:two add si,ax mov si,[si] ;Get BPB address pop ds ;DS = driver segment mov ah,53h int 21h ;Build DIB mov ax,es:[bp + 2] ;Get sector size from DIB mov es,cs:dos_seg add cs:ad_mem,DIB_SIZE ;Add DIB size cmp ax,es:MAX_SECTOR ;Compare it with max. sector size jbe create_ok ;If smaller than OK ; les bp,dword ptr cs:DIB_offs ;ES:BP - current DIB address ; dec byte ptr es:[bp] ;decrement drive number lea dx,err5 stc jmp drop_regs create_ok: clc drop_regs: pop ds ret create_DIB endp ;............................................................................... ; create_DA: ; creates Drive Area (or else Current Directory Structure) for the drive ;............................................................................... create_DA proc near push cx push dx mov es,dos_seg inc byte ptr es:NUM_OF_DRV ;Increase real number of drives mov al,byte ptr es:NUM_OF_DRV call get_DA_addr add al,40h ;Convert to ASCI letter mov es:[di],al ;Put it into DA add di,43h mov ax,4000h ;Signal that drive exists stosw mov ax,DIB_offs stosw ;Set DIB offset mov ax,DIB_seg stosw ;Set DIB segment mov ax,0 stosw mov ax,0ffffh stosw stosw mov ax,2 stosw create_end: pop dx pop cx ret create_DA endp ;...............................................................................; ; get_DA_addr: ; calculates address of Drive Area for drive AL ; INPUT: ; AL - drive number,eg. 1 - A:, 2 - B:, ... ; ; OUTPUT: ; ; ES:DI - address of Drive Area for drive AL ; ;...............................................................................; get_DA_addr proc near push ax push dx dec al xor ah,ah mov dl,51h ;Set DA ... add dl,dos_dep2 ; ... size mul dl ;Multiply by DA size mov es,dos_seg les di,dword ptr es:FIRST_DA ;Get addr. of first DA add di,ax ;So now ES:DI points to new DA pop dx pop ax ret get_DA_addr endp ;............................................................................... ; check_DA: ; checks whether already installed devices are not network or SUBSTed ones ;............................................................................... check_DA proc near mov es,dos_seg mov al,byte ptr es:NUM_OF_DRV ;Get real number of drives xor ch,ch mov cl,units mov ah,byte ptr es:TOTAL_NUM ;Get total number of drives check_next_DA: inc al cmp al,ah lea dx,err4 ja check_err_end call get_DA_addr ;Get address of DA to ES:DI cmp word ptr es:[di + 43h],ZERO ;DA not used ? jz check_loop ;Yes,jump lea dx,err6 check_err_end: stc ;Signal error ret check_loop: loop check_next_DA clc ret check_DA endp ;................................................................................ ; restore: ; restores previous state of Drive Area ;................................................................................ restore proc near les bx,dword ptr lastDIB_offs mov si,dos_dep3 mov word ptr es:[si + bx + 18h],0ffffh ;Mark it as the last DIB mov al,es:[bx] ;Get last drive nimber inc al mov es,dos_seg mov ah,byte ptr es:NUM_OF_DRV ;Get real number of drives mov byte ptr es:NUM_OF_DRV,al ;Restore real number of drives cmp_numb: cmp ah,al jz restore_end inc al call get_DA_addr ;Get address of DA to ES:DI mov word ptr es:[di + 43h],ZERO ;Mark DA as not used jmp cmp_numb restore_end: ret restore endp ;................................................................................. two db 2 ;byte = 2h DOS_V5 equ 1 UMB_USED equ 2 LOAD_HIGH equ 4 OWN_XMS equ 8 flags db 0 ;B0 set if DOS v5.xx ;B1 set if UMB used ;B2 set if driver is to be load high ;B3 set if XMS handler changed mem_flag db 0 ;memory allocation flag link_stat db 0 ;UMB link status dos_dep dw 0 ;0 - if dos 3.xx, 6 - if dos 4.xx or 5.xx dos_dep2 db 0 ;0 - if dos 3.xx, 7 - if dos 4.xx or 5.xx dos_dep3 dw 0 ;0 - if dos 3.xx, 1 - if dos 4.xx or 5.xx dos_seg dw 0 ;IMBDOS segment our_seg dw 0 ;our initial segment ad_mem dw 0 ;Mem. occupied by DIBs drv_beg dw 0 ;Start of driver (must be on para boundry) drv_seg dw 0 ;Segment addr. of driver dev_offs dw 0 ;Pointer to driver ... dev_seg dw 0 ; ... strat/interr routine DIB_offs dw 0 ;Address of ... DIB_seg dw 0 ; ... driver's DIB lastDIB_offs dw 0 ;Address of ... lastDIB_seg dw 0 ; ... the last DIB Request_Header label byte header_length db HLEN unit_code db ? command_code db INIT status dw 0 reserved dq 0 units db ? ending_offset dw ? ending_segment dw ? args_offset dw ? args_seg dw ? drive_num db ? HLEN equ $ - header_length error_msg dw 0 ;used by DOS v4.xx HLEN2 equ $ - header_length sign db 'IdrvCB ' SIG_LEN equ $ - sign ;............................................................................... fname db 128 dup (0) err3 db 'IDrv: INIT error!',cr,lf,lf,'$' err4 db 'IDrv: Too small LASTDRIVE specified!',cr,lf,lf,'$' err5 db 'IDrv: Sector size too large!',cr,lf,lf,'$' err6 db "IDrv: Can't install device after SUBSTed and network device!",cr,lf,lf,'$' err7 db 'IDrv: Memory allocation error!',cr,lf,lf,'$' ;............................................................................... err10 db 'IDrv: File not found!',cr,lf,lf,'$' err11 db 'IDrv: SEEK error!',cr,lf,lf,'$' err12 db 'IDrv: READ error!',cr,lf,lf,'$' err13 db 'IDrv: File too large!',cr,lf,lf,'$' ;............................................................................... starter: lea dx,header call print_msg mov ah,30h int 21h ;Get DOS version number lea dx,err_txt cmp al,3 jb pr_txt check_ver: je get_list ;DOS v3.xx cmp al,5 ;ver. above 5 ? ja pr_txt ;yes,jump jne dos_v4 or flags,DOS_V5 ;DOS v5.xx dos_v4: mov dos_dep,6 ;No,change entry length of Open Files Table mov dos_dep2,7 ;Change entry length of Drive Area mov dos_dep3,1 ;Change entry length of Disk Info Block mov header_length,HLEN2 ;Increase header length get_list: mov ah,52h int 21h ;Get vector for int 25H mov dos_seg,es lea dx,not_PC_Dos cmp word ptr es:52h,'UN' ;NUL device ? jne pr_txt ;No,jump les di,dword ptr es:02ah ;get address of DOS file table add di,dos_dep ;change entry length of OFT if necessary cmp byte ptr es:[di + 05bh],'C' ;Entry for dev. CON ? jne pr_txt cmp word ptr es:[di + 05ch],'NO' jne pr_txt mov si,80h mov ax,our_seg mov es,ax mov di,offset fname xor cx,cx get_char: inc si mov al,es:[si] cmp al,CR jz end_of_name cmp al,TAB ;Is it Tab ? jz is_any ;Yes,jump cmp al,' ' ;Is it space ? jnz check_if_first ;No,jump is_any: or cx,cx ;Any char moved ? jz get_char ;No,jump to get next char jmp go_on ;Yes(it means end of file name) pr_txt: jmp exit ;Jump to print message and qiut check_if_first: or cx,cx jnz move_char cmp al,'-' jnz set_args_addr inc si mov al,es:[si] cmp al,'l' jz get_char cmp al,'h' lea dx,inv_option jnz pr_txt or flags,LOAD_HIGH jmp get_char set_args_addr: mov args_offset,si ;Point to first char (in PSP) ... mov args_seg,es ; ... of the file name move_char: mov [di],al inc di inc cx jmp get_char end_of_name: or cx,cx jnz go_on lea dx,help_scr mov bx,1 mov cx,HELP_LEN mov ah,40h int 21h jmp exit_no_print go_on: ;....................................................... ; XMS support !!!!!! mov ax,4300h int 2fh cmp al,80h jne no_xms mov ax,4310h int 2fh check_xms: cmp word ptr es:[bx],JMP_SHORT ;is it short jmp ? je place_jmp cmp byte ptr es:[bx],JMP_FAR ;is it jmp xxxx:yyyy ? jne no_xms les bx,dword ptr es:[bx + 1] jmp check_xms place_jmp: cmp word ptr es:[bx + 2],9090h ;Nop instructions ? jne no_xms or flags,OWN_XMS ;signal that XMS handler changed mov prv_offs,bx mov prv_seg,es mov xms_offs,bx add xms_offs,5 ;set offset to point after jmp instruction mov xms_seg,es mov ax,es:[bx + 5] mov word ptr old_code,ax mov ax,es:[bx + 7] ;save 5 bytes of code mov word ptr old_code + 2,ax mov al,es:[bx + 9] mov old_code + 4,al cli mov byte ptr es:[bx + 5],JMP_FAR ;place there jmp far to our xms handler mov ax,offset xms_handler mov word ptr es:[bx + 6],ax mov ax,cs mov word ptr es:[bx + 8],ax sti no_xms: mov drv_beg,ZERO mov ax,our_seg add ax,10h ;add PSP size (in paras) mov dev_seg,ax ;Set seg. address of device driver jmp ldrv ;............................................................................... old_code db 5 dup(0) CODE_LEN equ $ - old_code xms_vector label dword xms_offs dw 0 xms_seg dw 0 prv_vector label dword prv_offs dw 0 prv_seg dw 0 handle dw 0 ;------------------------------------------------------------------------------- ;New XMS handdler ;------------------------------------------------------------------------------- xms_handler: pushf push ax push di push es les di,cs:xms_vector mov ax,word ptr cs:old_code ;restore previous state ... cli stosw ; ... of XMS entry ... mov ax,word ptr cs:old_code + 2 stosw mov al,cs:old_code + 4 stosb sti pop es pop di pop ax cmp ah,9 ;Allocate extended memory block ? jnz xms_jmp ;No,jump popf call cs:xms_vector ;call original XMS handler pushf or ax,ax jz xms_end mov cs:handle,dx xms_end: popf retf xms_jmp: popf call cs:xms_vector push es push bx push ax les bx,cs:xms_vector cli mov byte ptr es:[bx],JMP_FAR ;place there jmp far to our XMS handler mov ax,offset xms_handler mov word ptr es:[bx + 1],ax mov ax,cs mov word ptr es:[bx + 3],ax sti pop ax pop bx pop es retf ;............................................................................... ; restore_xms: ; restores previous state of original XMS handler ;............................................................................... restore_xms proc near test flags,OWN_XMS ;XMS handler changed ? jz res_xms_end ;No,jump push es push di les di,xms_vector mov si,offset old_code mov cx,CODE_LEN cld cli rep movsb sti pop di pop es res_xms_end: ret restore_xms endp ;............................................................................... ; free_xmem: ; frees extended memory block and replaces (in original XMS handler) ; JMP xxxx:yyyy with JMP_SHORT and three NOP. ;............................................................................... free_xmem proc near test flags,OWN_XMS ;XMS supported ? jz free_xmem_end ;no,jump to quit les bx,prv_vector cli mov word ptr es:[bx],JMP_SHORT ;place there JMP short & ... mov word ptr es:[bx + 2],9090h ; ... three NOPs mov byte ptr es:[bx + 4],90h sti mov dx,handle or dx,dx jz free_xmem_end mov ah,0ah call cs:xms_vector ;free memory free_xmem_end: ret free_xmem endp ;............................................................................... ; messages to display db 'Program written by Janusz Wojcik' err_txt db 'IDrv: That version of DOS is not supported!',cr,lf,lf,'$' not_PC_Dos db 'IDrv: Not PC DOS ',cr,lf,lf,'$' help_scr db 'usage: idrv [options] [d:\path\]filename.ext [parms]',cr,lf db 'options:',cr,lf db ' -h = load high (in UMB)',cr,lf db " -l = load low (default)",cr,lf db cr,lf db 'If you find this program useful please send $10 to:',cr,lf db ' Janusz Wojcik',cr,lf db ' 20-608 Lublin',cr,lf db ' ul.Wajdeloty 6/13',cr,lf db ' Poland',cr,lf HELP_LEN equ $ - help_scr inv_option db 'IDrv: invalid option! ',cr,lf,lf,'$' header db 'Device Drivers Installer v1.06',cr,lf db '(C) 1990 by Janusz Wojcik Lublin,Poland.',cr,lf,lf,'$' ;.................................................................................... LEN equ $ - new_seg code ENDS END start