Serial Number

 BBS: Inland Empire Archive
Date: 04-18-92 (23:31)             Number: 101
From: DAVID BLISS                  Refer#: NONE
  To: ALL                           Recvd: NO  
Subj: Serial Number                  Conf: (2) Quik_Bas

Someone suggested using the disk's serial number as a copy
protect/timelock.  However, this code will allow you to
change the serial number of any dos4+ disk to anything you
want...

'ChngSer - Changes disk serial number
'You may use this code for anything except profit.
'Compile with QB.LIB...
DECLARE FUNCTION unhex! (x$)
'$INCLUDE: 'qb.bi'        This loads the REGTYPEX type...
DIM inregs AS RegTypeX, outregs AS RegTypeX
PRINT
INPUT "Modify which disk? (A-Z) ", disc$
disc = ASC(UCASE$(disc$)) - 64
inregs.ax = &H6900
inregs.bx = disc
DIM diskinfo AS STRING * 26
inregs.ds = VARSEG(diskinfo)
inregs.dx = VARPTR(diskinfo)
CALL interruptx(&H21, inregs, outregs)
di$ = diskinfo
PRINT
PRINT "Current serial number: ";
FOR x = 4 TO 1 STEP -1
PRINT HEX$(ASC(MID$(diskinfo, x + 2, 1)));
NEXT x
PRINT
INPUT "New serial number? (8 hex digits) ", b$
b$ = UCASE$(b$)
a = unhex(LEFT$(b$, 2))
b = unhex(MID$(b$, 3, 2))
c = unhex(MID$(b$, 5, 2))
d = unhex(MID$(b$, 7, 2))
newser$ = CHR$(d) + CHR$(c) + CHR$(b) + CHR$(a)
MID$(diskinfo, 3, 4) = newser$
inregs.ax = &H6901
inregs.bx = disc
inregs.ds = VARSEG(diskinfo)
inregs.dx = VARPTR(diskinfo)
CALL interruptx(&H21, inregs, outregs)

FUNCTION unhex! (x$)
FOR x = LEN(x$) TO 1 STEP -1
a$ = MID$(x$, LEN(x$) - x + 1, 1)
IF a$ <= "9" THEN
    a = VAL(a$)
ELSE
    IF a$ = "F" THEN a = 15
    IF a$ = "E" THEN a = 14
    IF a$ = "D" THEN a = 13
    IF a$ = "C" THEN a = 12
    IF a$ = "B" THEN a = 11
    IF a$ = "A" THEN a = 10
END IF
tempvar = tempvar + (a * 16 ^ (x - 1))
NEXT x
unhex! = tempvar
END FUNCTION

Dave

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 * Origin: The Aliens BBS, Simpsonville SC, 8032347195 (1:3639/4)