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From: Wolfgang Kern on 17 Apr 2008 06:54 Hello almas, > Note : if i have to replace [Ctrl - C] ascii 003 ; some programs refuse it. > Same for ascii [ ALT 10 ] or alt 6 Yes, a few codes are covered by the DOS-prompt itself, so an ALT-10 will just do what it says: "LF" and ALT 7 may just beep once. > Sure i can do a XOR 20h on each bytes of a file ; byte 0 become 20h > and i can move the Space... > then i do again XOR 20h.... and not modified bytes have again same value. wouldn't it be enough to filter off all non-numeric/hex characters ? ie: make a question-mark or whatsoever out of it > The idea is to type with numbers and letters > Example i type "50", the program write " P " > If i type "A8" the programm write " � " Yes, even I'd treat non-printatble chararcters in a special way, some may be interpreted as CRSR-position, KEY-buffer- or screen-commands depending on the options of the print-function. I think you use the 'display all' option for INT21h anyway yet. > I can type 00 ; 01 ;02 ... 0E,0F 10,11,12.....and so long...FE FF > I just obtain One byte 0 to 0FFh > The byte falls at the location hexa... i catch it. > The next operation : find the byte a hexa_address and remove it. > With this part of programm i can choose the byte i will remove. > Before it, i had to build 256 tools... for each bytes. > > I am sorry, but do not understand you want to do. > > after > cmp al,41h jb error > cmp al,46h jb error *** "ja" error > sub al,7 ; i can obtain 3Ah to 40h ( do" :" to " @ ") why ? It will result in 3A..3F !! followed by the sub 30h => "0A...0F" I meant the two lines above within my comments :) lodsb cmp al,30h jb not_a_Number ; cmp al,3Ah jb chiffre_d ; d for ten : ( forty, *fivety*, 60 and so long) cmp al,41h ; is it an Hexa letter ? jb error cmp al,46h ja error ;*** > sub al,37h ; "A" > 0Ah "F" become 0Fh ;*** > jmp short high_size ;*** I'd replace the two lines above with sub al,07 ;*** a JMP costs more than one *SUB* and the code become shorter too sub al,07 ;will be executed ONLY IF AL = 41..46h (become 3A.. chiffre_d: ;else it goes here AL = 30..39h sub al,30h ; "0" > 00h "9" become 09h shl al,4 ;move it four bits = MUL by 16 mov ah,al ;save high nibble value in AH ie:yet (without using bx) ;AH= x0h (x = 0..F) lodsb ... ;code for the LOW-nibble goes here ;AL =0xh (x = 0..F) or AL,AH ;combine the two (same as ADD AL,AH here) ;the final value is now in AL ;mov AH,0 ;not required at all mov offset hex_string, AL ; if you use AX here the value of AH would go to ; offset "hex-string+1" (little endians in here ...) ; but isn't there a zero anyway ? > I do xor bx,bx so bx=0000 > I have to save value of AX, so i put it into bx > then, i must have Ah=0 al =...? come from the lodsbyte Why do you need AH=0 ? as a string-terminator for a single byte ? I'd write just the gotten byte into the hexa-string, and keep the anyway defined zero in there if you really need it. > Yes : the character "d" and "u" make *together* the byte "DU" > So, i do "letter d" becomes "d *16" d = 0 to F Mmh, after multiply by 16 (= shift left 4):d = 00..F0 > and i do d*16 + u U can also have value 0 to 0Fh Yes, you can ADD 'or' OR this two, because both values are only four bits in size and at the proper bit-position already. your byte: 76543210 ;bit position 0000xxxx ;low nibble in AL +yyyy0000 ;high nibble as saved in AH (or elsewhere) -------- yyyyxxxx ;regardless of ADD or OR here. > Right : for the low size ; cx, is not usefull > ... may be it could be or ah,bl either OR AL,.. ;any-byte-reg where you saved the high nibble or ADD AL,.. ; MOV offset ... ,AL ;you got only one byte to alter the display :) > At the end, i just use one "$" for flag end of text. > the most important is text terminate by $ Yes, for int21h-text, while int10h-text let you choose your own end mark/size. __ wolfgang
From: almas on 17 Apr 2008 14:52 Guten Tag Wolfgang. Hi everybody I try the solution, it just cost 70 bytes. I choose a very small size of file. mov si,0082h ; Sure, i must respect the syntax lodsb cmp al,3Ah ; what if one typed any of !"+-*().. or an ALT-num<30 ? jb chiffre_d ; d for ten : ( forty, fivety, 60 and so long) cmp al,41h ; is it an Hexa letter ? jb error cmp al,46h ja error ; sub al,07 jmp short high_size chiffre_d: ; can be 0 to 9 but no think else sub al,30h ; "0" > 00h "9" become 09h high_size: SHL AL,4 ; (= *16 and clears low 4 bits also) (00,01..0Fh becomes 00,10..F0h) xchg ax,bx ; i just use 1 byte sure "mov bl,al" do the same. lodsb cmp al,3Ah jb chiffre_u ; U like Unit cmp al,41h ; for Unit, i have not to Rotate On Left jb error ; so it just need One Sub al, [a value] cmp al,46h ja error sub al,37h jmp short low_size chiffre_u: ; > *** same as mentioned above ... sub al,30h low_size: add ax,bx ; it use 2 bytes ; but OR AL,BL is more logic. ; you have lower nibble (4 bits) in AL now ; and higher nibble shifted (*16) and saved in BL. ; Two hex-characters wont ever produce more than one byte. ; It will work if you add AX,BX, but I'd use OR AL,BL ; or does your DOS support Unicode ? :) ... then mov AH,0 would do it. mov offset hexa,ax ; *** why two characters ? (the 2nd will be zero):"?" or so... ; mov dx,offset hexa jmp short display_it int 20h ; when this be executed ? error: mov dx,offset txt ; i display the "how o use" and the result in same time mov ah,9 int 21h ret ; just cost 1 byte, int 20h also works txt db: "Asci2Hex" ,9 ; Yes no $ here ! hexa db: 32,10,36 ; Ascii "10" go line below "36" terminate display text Best regards "Wolfgang Kern" <nowhere(a)never.at> a �crit dans le message de news: fu7a8m$lgs$1(a)newsreader2.utanet.at... > > Hello almas, > >> Note : if i have to replace [Ctrl - C] ascii 003 ; some programs refuse > it. >> Same for ascii [ ALT 10 ] or alt 6 > > Yes, a few codes are covered by the DOS-prompt itself, so an ALT-10 > will just do what it says: "LF" and ALT 7 may just beep once. > >> Sure i can do a XOR 20h on each bytes of a file ; byte 0 become 20h >> and i can move the Space... >> then i do again XOR 20h.... and not modified bytes have again same value. > > wouldn't it be enough to filter off all non-numeric/hex characters ? > ie: make a question-mark or whatsoever out of it > >> The idea is to type with numbers and letters >> Example i type "50", the program write " P " >> If i type "A8" the programm write " � " > > Yes, even I'd treat non-printatble chararcters in a special way, some > may be interpreted as CRSR-position, KEY-buffer- or screen-commands > depending on the options of the print-function. I think you use the > 'display all' option for INT21h anyway yet. > >> I can type 00 ; 01 ;02 ... 0E,0F 10,11,12.....and so long...FE FF >> I just obtain One byte 0 to 0FFh > >> The byte falls at the location hexa... i catch it. >> The next operation : find the byte a hexa_address and remove it. > >> With this part of programm i can choose the byte i will remove. >> Before it, i had to build 256 tools... for each bytes. >> >> I am sorry, but do not understand you want to do. >> >> after >> cmp al,41h jb error >> cmp al,46h jb error *** "ja" error >> sub al,7 ; i can obtain 3Ah to 40h ( do" :" to " @ ") why ? > > It will result in 3A..3F !! followed by the sub 30h => "0A...0F" > > I meant the two lines above within my comments :) > lodsb > cmp al,30h > jb not_a_Number ; > cmp al,3Ah > jb chiffre_d ; d for ten : ( forty, *fivety*, 60 and so long) > cmp al,41h ; is it an Hexa letter ? > jb error > cmp al,46h > ja error > ;*** > sub al,37h ; "A" > 0Ah "F" become 0Fh > ;*** > jmp short high_size > ;*** I'd replace the two lines above with sub al,07 > ;*** a JMP costs more than one *SUB* and the code become shorter too > sub al,07 ;will be executed ONLY IF AL = 41..46h (become 3A.. > chiffre_d: ;else it goes here AL = 30..39h > sub al,30h ; "0" > 00h "9" become 09h > shl al,4 ;move it four bits = MUL by 16 > mov ah,al ;save high nibble value in AH ie:yet (without using bx) > ;AH= x0h (x = 0..F) > lodsb ... ;code for the LOW-nibble goes here > ;AL =0xh (x = 0..F) > or AL,AH ;combine the two (same as ADD AL,AH here) > ;the final value is now in AL > ;mov AH,0 ;not required at all > mov offset hex_string, AL > ; if you use AX here the value of AH would go to > ; offset "hex-string+1" (little endians in here ...) > ; but isn't there a zero anyway ? > > >> I do xor bx,bx so bx=0000 >> I have to save value of AX, so i put it into bx >> then, i must have Ah=0 al =...? come from the lodsbyte > > Why do you need AH=0 ? as a string-terminator for a single byte ? > I'd write just the gotten byte into the hexa-string, and > keep the anyway defined zero in there if you really need it. > >> Yes : the character "d" and "u" make *together* the byte "DU" >> So, i do "letter d" becomes "d *16" d = 0 to F > > Mmh, after multiply by 16 (= shift left 4):d = 00..F0 > >> and i do d*16 + u U can also have value 0 to 0Fh > > Yes, you can ADD 'or' OR this two, because both values are only > four bits in size and at the proper bit-position already. > your byte: > 76543210 ;bit position > 0000xxxx ;low nibble in AL > +yyyy0000 ;high nibble as saved in AH (or elsewhere) > -------- > yyyyxxxx ;regardless of ADD or OR here. > >> Right : for the low size ; cx, is not usefull >> ... may be it could be or ah,bl > > either > OR AL,.. ;any-byte-reg where you saved the high nibble > or > ADD AL,.. ; > MOV offset ... ,AL ;you got only one byte to alter the display :) > >> At the end, i just use one "$" for flag end of text. >> the most important is text terminate by $ > > Yes, for int21h-text, > while int10h-text let you choose your own end mark/size. > > __ > wolfgang > > >
From: Wolfgang Kern on 18 Apr 2008 17:34 almas wrote: > Guten Tag Wolfgang. :) Bon Jour! or similar, my French is restricted to doing it :) > Hi everybody > I try the solution, it just cost 70 bytes. I choose a very small size of > file. If code size is your main concern you can make CALLs out of the two identical parts in the conversion: But you know that DOS files always occupy a whole cluster on disk and that the PSP is 256 bytes large, beside the environment copy anyway. I limit my modular code to disk sector bounds (multiple of 512 bytes). ie: also just 32(26)+22(18)+13(8) = 71(52) code-bytes, the figures in brackets mean without the out-commented functionality. _____________________ mov esi,0082h ; I see, you assume a space before the parameters ;cmp byte [esi-2],0 ; a few buyes more, but perhaps useful ;jz error ;if commandline is empty lodsw ;get both bytes at once call convert ;modify AL set carry/NC on error/GOOD jc error shl al,4 exch al,ah ;save first and use second yet call convert ;call the same again jc error or al,ah mov offset hexa,AL jmp short display_quit convert: ; cmp al,30h ;I'd put this in ; jc oh_no ;jc == jb cmp al,3ah jc num cmp al,41h jc oh_no cmp al,46h cmc ;invert the carry-bit (error if NoCarry >46h) jc oh_no sub al,07h num: sub al,30h oh_no: ret ;the last SUB will always result in NoCarry ;while any error got a set Carry-flag now. error: ; mov dx,errtxt ; jmp short error_quit display_quit: mov dx,txt error_quit: mov AH,09 int 21h ret ;it will work, even I'd always use: ; mov ax,4c00h ;because DOS will restore its stack and ; int21h ;segment-registers on termination then. txt: hexa: errtxt: ... ______________________________ > mov si,0082h ; Sure, i must respect the syntax > lodsb > cmp al,3Ah ; what if one typed any of !"+-*().. or an ALT-num<30 ? > jb chiffre_d ; d for ten : ( forty, fivety, 60 and so long) > cmp al,41h ; is it an Hexa letter ? > jb error > cmp al,46h > ja error ; > sub al,07 *** remove this line: > jmp short high_size > chiffre_d: ; can be 0 to 9 but no think else ( It can be anything else if you input characters with code below 30h ie: !"#$%^&()*+,-./ 20..2Fh) > sub al,30h ; "0" > 00h "9" become 09h *** and this label become obsolete then: > high_size: > SHL AL,4 ; (= *16 and clears low 4 bits also) (00,01..0Fh becomes > 00,10..F0h) > xchg ax,bx ; i just use 1 byte sure "mov bl,al" do the same. I see, it's OK if you prefer short code. > lodsb > cmp al,3Ah > jb chiffre_u ; U like Unit > cmp al,41h ; for Unit, i have not to Rotate On Left > jb error ; so it just need One Sub al, [a value] > cmp al,46h > ja error *** sub al,07h ; the difference of "41h-3Ah" = 7 chiffre_u: ; > *** same as mentioned above ... sub al,30h ; if it was 41..46 then we sub 7 'and' sub 30h (sub 37h) ***; > low_size: > add ax,bx ; it use 2 bytes ; but OR AL,BL is more logic. > ; you have lower nibble (4 bits) in AL now > ; and higher nibble shifted (*16) and saved in BL. > ; Two hex-characters wont ever produce more than one byte. > ; It will work if you add AX,BX, but I'd use OR AL,BL > ; or does your DOS support Unicode ? :) ... then mov AH,0 would do it. > mov offset hexa,ax > ; *** why two characters ? (the 2nd will be zero):"?" or so... > ; mov dx,offset hexa jmp short display_it int 20h > error: > mov dx,offset txt ; i display the "how o use" and the result in same > time > mov ah,9 > int 21h > ret ; just cost 1 byte, int 20h also works Yes, as long it's a DOS-.com file and you don't alter the stack. > txt db: "Asci2Hex" ,9 ; Yes no $ here ! > hexa db: 32,10,36 ; Ascii "10" go line below "36" terminate display > text Right, but if you like any next line to start left-most, then you should insert a CR as well: hexa: db 32,10,13,36 __ wolfgang
From: Wolfgang Kern on 19 Apr 2008 05:10 I posted a bug with this: > _____________________ > mov esi,0082h ; I see, you assume a space before the parameters > ;cmp byte [esi-2],0 ; a few buyes more, but perhaps useful > ;jz error ;if commandline is empty > lodsw ;get both bytes at once > call convert ;modify AL set carry/NC on error/GOOD > jc error > shl al,4 > exch al,ah ;save first and use second yet > call convert ;call the same again > jc error > or al,ah > mov offset hexa,AL > jmp short display_quit > > convert: > ; cmp al,30h ;I'd put this in > ; jc oh_no ;jc == jb > cmp al,3ah > jc num > cmp al,41h > jc oh_no *** > cmp al,46h *** make this CMP AL,47h (error if >=) because 46h shall not be an error. *** > cmc ;invert the carry-bit (error if NoCarry >46h) > jc oh_no > sub al,07h > num: > sub al,30h > oh_no: > ret ;the last SUB will always result in NoCarry > ;while any error got a set Carry-flag now. > error: > ; mov dx,errtxt > ; jmp short error_quit > display_quit: > mov dx,txt > error_quit: > mov AH,09 > int 21h > ret ;it will work, even I'd always use: > ; mov ax,4c00h ;because DOS will restore its stack and > ; int21h ;segment-registers on termination then. > txt: > hexa: > errtxt: ... > ______________________________ __ wolfgang
From: almas on 19 Apr 2008 10:08 Guten Tag / Bonjour / Good morning ( or afternoon ) Danke sh�n Wolfgang. I know : a file use 1 cluster or more. The file will be just a part of a larger one. so may be i have to care about the size. In fact, i prefer a small size. I will try the solution with a call. Best regards Almas "Wolfgang Kern" <nowhere(a)never.at> a �crit dans le message de news: fuccus$183$1(a)newsreader2.utanet.at... > > I posted a bug with this: > >> _____________________ >> mov esi,0082h ; I see, you assume a space before the parameters >> ;cmp byte [esi-2],0 ; a few buyes more, but perhaps useful >> ;jz error ;if commandline is empty >> lodsw ;get both bytes at once >> call convert ;modify AL set carry/NC on error/GOOD >> jc error >> shl al,4 >> exch al,ah ;save first and use second yet >> call convert ;call the same again >> jc error >> or al,ah >> mov offset hexa,AL >> jmp short display_quit >> >> convert: >> ; cmp al,30h ;I'd put this in >> ; jc oh_no ;jc == jb >> cmp al,3ah >> jc num >> cmp al,41h >> jc oh_no > *** >> cmp al,46h *** make this CMP AL,47h (error if >=) > because 46h shall not be an error. > *** >> cmc ;invert the carry-bit (error if NoCarry >46h) >> jc oh_no >> sub al,07h >> num: >> sub al,30h >> oh_no: >> ret ;the last SUB will always result in NoCarry >> ;while any error got a set Carry-flag now. >> error: >> ; mov dx,errtxt >> ; jmp short error_quit >> display_quit: >> mov dx,txt >> error_quit: >> mov AH,09 >> int 21h >> ret ;it will work, even I'd always use: >> ; mov ax,4c00h ;because DOS will restore its stack and >> ; int21h ;segment-registers on termination then. >> txt: >> hexa: >> errtxt: ... >> ______________________________ > > __ > wolfgang > > >
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