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             STEP BY STEP GUIDE TO BACKING-UP DISKS
                              WITH
                         NIBBLES AWAY ][

     THERE ARE THREE BASIC STEPS TO BACKUP A DISKETTE:

1. LOCATE THE TRACKS WHICH CONTAIN DATA.
2. FIND THE ADDRESS MARKER FOR THE SECTORS THERE.
3. FIGURE OUT ANY ADDITIONAL PROTECTION.

(HINT: #3 IS THE HARD ONE!)

     FOR  MOST  OF  THE PROCEDURES BELOW,  A BASIC WORKING  KNOWLEDGE  OF  THE
TRACK/BIT EDITOR (TBE) IS REQUIRED.   FOR THOSE WHO ARE NOT FAMILIAR WITH  THE
TBE,  AN OVERALL DESCRIPTION AND SOME EXAMPLES ARE GIVEN BELOW.   THE EXAMPLES
ARE  EASIER TO UNDERSTAND IF THEY ARE PERFORMED AS YOU READ THIS,  SO YOU  MAY
WANT TO BOOT UP NIBBLES AWAY ][ AND TRY THEM OUT TO GET A BETTER UNDERSTANDING
OF WHAT IS GOING ON.

     ENTER  THE  TBE  BY SELECTING OPTION 'T' FROM THE  MAIN  MENU.   A  LARGE
SECTION  OF  NUMBERS WILL APPEAR ON THE SCREEN,  WITH TWO DASHED LINES AT  THE
TOP.   THE  INFORMATION IN BETWEEN THESE LINES IS THE STATUS  INFORMATION  AND
INFORMS YOU OF SUCH THINGS AS CURSOR POSITION,  TRACK NUMBER,  AND IS ALSO THE
LOCATION  WHERE VARIOUS PROMPTS APPEAR FOR CERTAIN FUNCTIONS.   THE NUMBERS AT
THE  BOTTOM  ARE SEPARATED INTO TWO SECTIONS.   ON THE LEFT ARE  THE  STARTING
MEMORY  ADDRESS'S FOR EACH LINE TO THE RIGHT.   MOVE THE CURSOR  AROUND  USING
I,J,K OR M, AND WATCH THE ADDR INDICATOR IN THE STATUS LINE.  IT WILL TELL YOU
EXACTLY WHAT MEMORY ADDRESS THE VALUE UNDER THE CURSOR REPRESENTS.   THE ARROW
KEYS  CHANGE THE AREA OF MEMORY WHICH YOU CAN SEE.   THEY SHIFT YOUR VIEW  256
BYTES FORWARD OR BACKWARD AT A TIME.   THE ONLY REALLY IMPORTANT THING TO KNOW
FOR  THIS DISCUSSION IS HOW TO USE THE ARROW KEYS TO MOVE THE VIEWING 'WINDOW'
AROUND IN MEMORY.
     THE  ';'  (UNSHIFTED '+') AND THE '-' KEYS INCREMENT  AND  DECREMENT  THE
TRACK  NUMBER IN THE STATUS LINE.   PRESSING 'R' WILL CAUSE DRIVE ONE TO  READ
THE  DATA FROM THE TRACK INDICATED IN THE STATUS LINE INTO MEMORY.   THE BYTES
ON THE SCREEN WILL CHANGE,  SINCE DIFFERENT DATA HAS BEEN READ  IN.   PRESSING
THE  'R'  KEY  MULTIPLE TIMES WILL RESULT IN DIFFERENT DATA  BEING  DISPLAYED.
THIS IS BECAUSE NIBBLES AWAY ][ STARTS READING AT WHATEVER POINT HAPPENS TO BE
UNDER THE HEAD WHEN THE DRIVE IS TURNED ON,  WHICH IS RANDOM, HENCE THE CHANGE
IN  THE  DISPLAYED DATA (THE DATA IS NOT ACTUALLY DIFFERENT,  IT IS  JUST  NOT
LOADED AT THE SAME MEMORY LOCATION AS IT WAS PREVIOUSLY).

STEP 1:
     TO  DO  THIS WE MUST LOCATE ALL OF THE TRACKS ON THE DISK  WHICH  CONTAIN
DATA.   TO DO THIS WE SHOULD HAVE THE TRACK POINTER SET TO TRACK 00.  PRESSING
'R'  WILL READ IN THE TRACK AND SHOW IT ON THE SCREEN.   THE ARROW KEYS SHOULD
BE  USED  TO MOVE THE VIEWING 'WINDOW' TO START AT $2000.   NOW WE  WILL  MOVE
FORWARD  AND TRY TO DETERMINE IF THIS TRACK CONTAINS  VALID  DATA.   ACTUALLY,
TRACK 00 MUST CONTAIN SOME DATA IN ORDER FOR THE DISK TO BOOT,  BUT WE WILL BE
USING THIS PROCEDURE ON OTHER TRACKS WHICH DO NOT NECESSARILY CONTAIN DATA.
     THE  MAIN  THING  WHICH WILL IDENTIFY A TRACK AS CONTAINING DATA  IS  THE
PRESENCE OF GAPS.   GAPS ARE SECTIONS OF THE SAME BYTE REPEATED SEVERAL TIMES.
NORMALLY THEY ARE MADE UP OF $FF'S AND ARE 6-20 IN LENGTH.   TO SEE WHAT THESE
LOOK  LIKE,  INSERT YOUR SYSTEM MASTER DISK AND READ IN TRACK 00 AS  DESCRIBED
ABOVE.   MOVING  THROUGH  THE BUFFER WITH THE ARROW KEYS WILL REVEAL  A  LARGE
VARIETY  OF VALUES.   SPACED OUT AMONG THESE SHOULD BE SECTIONS OF FF'S  WHICH
CONTAIN ABOUT 6-20 IN A ROW,  DEPENDING ON THE EXACT DISK.   NORMALLY DOS  3.2
DISKS HAVE LARGER GAPS THAN DOS 3.3 DISKS.  THERE SHOULD BE MANY OCCURANCES OF
THE  GAPS,  SPACED OUT SO THAT YOU SEE ONE ABOUT EVERY OTHER TIME THAT YOU USE
THE ARROW KEYS TO MOVE FORWARD OR BACKWARD.

NOTE:YOU  MAY SEE A SECOND,  SMALLER (2-5 $FF'S),  GAP FOLLOWING A LARGE  GAP,
     WITH  A SMALL SECTION OF DATA IN BETWEEN.   THIS IS CALLED THE  SECONDARY
     GAP.   WHEN  REFERING TO A GAP HERE,  WE WILL ALWAYS BE TALKING ABOUT THE
     PRIMARY GAP, NOT THE SECONDARY ONE.

     NOW TRY LOOKING AT OTHER TRACKS ON THE DISK.  FIRST LOOK ONLY AT THE FULL
TRACKS  (NO .5 ON THE END).   ALL OF THEM WILL BE SIMILAR TO TRACK 00  IN  THE
APPEARANCE  OF  THE GAPS.   YOU MAY WANT TO TRY THIS SEVERAL TIMES  TO  BECOME
COMFORTABLE WITH LOCATING GAPS ON A GIVEN TRACK.
     NOW READ IN A HALF TRACK (.5 ON THE END).   SCAN MEMORY TO LACATE SOME OF
THE GAPS.  SINCE SYSTEM MASTER DISKS DO NOT USE HALF-TRACKS, THE DATA WHICH WE
SEE HERE IS REALLY 'CROSS-TALK'.  IN OTHER WORDS, DATA WAS WRITTEN ON THE FULL
TRACK,  BUT  THE  MAGNETIC PATTERN SPREAD OUT A BIT,  AND SO WE SEE SOME  DATA
HERE.   THE TELL-TALE SIGN OF THIS PHENOMENA IS THAT THE GAPS WILL NOT BE  ALL
THE  SAME.   THAT IS,  THEY MAY HAVE ONE OR MORE VALUES IN THEM WHICH ARE  NOT
CONSISTENT.   THIS TELLS US THAT THERE IS SOME DATA ON THIS TRACK, BUT THAT IT
IS NOT VALID DATA.  TAKE A LOOK AT SOME OTHER HALF-TRACKS SO THAT YOU CAN TELL
IF YOU ARE LOOKING AT A FULL TRACK OR A HALF TRACK BY EXAMINING THE GAPS.
     THE NEXT ITEM WHICH YOU NEED TO BE ABLE TO IDENTIFY IS A BLANK TRACK.  TO
DO THIS, INSERT A BLANK (NON-INITIALIZED) DISK INTO DRIVE ONE.  READ ANY TRACK
ON  THIS  DISK AND SCAN THROUGH THE MEMORY ADDRESSES.   THERE WILL BE NO  GAPS
FOUND,  AND  MANY OF THE BYTES SEEN ON A TRACK LIKE THIS WILL END IN  0  (I.E.
$A0,$B0,$E0),  WHICH ARE NOT LEGAL DISK BYTES.  THIS MEANS THAT THE CONTROLLER
CAN FIND NO VALID DATA ON THE TRACK.  SOME DISKS HAVE PORTIONS OF TRACKS WHICH
ARE NOT USED,  SO YOU SHOULD ALWAYS BE SURE TO EXAMINE AT LEAST 24 SCREENFULLS
OF INFORMATION TO MAKE SURE THAT THERE IS NO DATA AT ANY POINT ON THE TRACK.
     OUR  NEXT  TOOL FOR FINDING DATA IS THE FACT THAT VALID DATA MUST  BE  AT
LEAST 1 TRACK APART.   IN OTHER WORDS,  IF YOU LOCATE DATA ON TRACK 3.5,  THEN
TRACK  4  CANNOT HAVE DATA AND THE NEXT PLACE WHERE DATA CAN BE IS TRACK  4.5.
THIS IS VERY HELPFUL FOR FINDING TRACKS WITH DATA.

NOTE: IF  YOU LOCATE DATA ON A GIVEN TRACK,  IT IS A GOOD IDEA TO LOOK AT  THE
     TRACKS  ONE HALF TRACK TO EITHER SIDE,  TO MAKE SURE THAT THEY LOOK  LESS
     VALID THAN THE ONE THAT YOU HAVE SELECTED AS THE REAL ONE.

     WELL,  NOW THAT WE KNOW HOW TO LOACATE DATA ON A TRACK,  WE CAN BEGIN  AT
TRACK 0 AND STEP TOWARDS TRACK 22, CHECKING EACH TRACK TO SEE IF IT APPEARS TO
HAVE DATA ON IT.   MOST DISKS HAVE A PATTERN TO THE POSITION OF THE DATA,  AND
IF  YOU CAN FIGURE IT OUT,  YOU MAY BE ABLE TO JUST CHECK A FEW TRACKS TO MAKE
SURE,  AND THEN GO ON TO STEP 2.  OTHERWISE THE DATA MUST BE LOCATED ONE TRACK
AT A TIME.
     MOST  DISKS USE THE STANDARD TRACKS (1,2,3,...,22),  BUT THERE  ARE  SOME
WHICH  USE HALF-TRACKS AND SOME WHICH USE ALL THE WAY OUT TO TRACK 23  (WHICH,
BY  THE WAY CANNOT BE READ ON ALL DRIVES SINCE NO DRIVES WERE EVER DESIGNED TO
GO OUT THAT FAR).
     WHEN ALL TRACKS WHICH CONTAIN SOME TYPE OF DATA ARE LOCATED,  WE CAN MOVE
ON TO STEP 2.

STEP 2:
     NOW  WE  MUST  TELL NIBBLES AWAY ][ HOW TO READ THE  INFORMATION  ON  THE
TRACKS WHICH WE HAVE FOUND TO CONTAIN VALID DATA.   THIS IS DONE BY GOING BACK
TO  EACH  OF THESE TRACKS WITH THE TBE AND FINDING THE ADDRESS MARK  FOR  EACH
ONE.   THE ADDRESS MARK WILL BE THE FIRST 3 BYTES FOLLOWING THE GAP.   TO  SEE
THIS IN OPERATION, TAKE A LOOK AT A TRACK FROM YOUR SYSTEM MASTER DISK.  AFTER
EACH  GAP YOU WILL SEE EITHER 'D5 AA 96' FOR A DOS 3.3 MASTER DISK,  OR 'D5 AA
B5' FOR A DOS 3.2 DISK.   THESE VALUES SHOULD BE NOTED DOWN ALONGSIDE OF  EACH
TRACK NUMBER WHICH CONTAINS DATA.  MANY TIMES THERE WILL BE ONLY ONE, OR MAYBE
2 PATTERNS FOR ALL TRACKS.
     AFTER  THIS,  WE  ARE  READY TO BACK-UP THESE TRACKS.   THIS IS  DONE  BY
EXITING THE TBE (USE 'Q') AND THEN SELECTING 'M' FOR THE MODIFIERS MENU.  THEN
SELECT 'B' FOR BACKUP MODIFIER.   WHEN ASKED 'USE ADDRESS MARK' ANSWER 'Y' AND
THEN TYPE IN THE ADDRESS MARK WHICH YOU NOTED DOWN FOR THE RANGE OF TRACKS  TO
BE  BACKED-UP.   SIMPLY  PRESS  RETURN TO THE REST OF THE QUESTIONS  AND  THEN
RETURN TO THE MAIN MENU.   SELECT 'N' TO ENTER NIBBLES AWAY ][, AND ANSWER 'Y'
TO THE QUESTION 'CHANGE DEFAULT OPTIONS'.  USE THE <RETURN> KEY TO MOVE TO THE
'START TRACK' PROMPT,  AND THEN ENTER THE FIRST TRACK TO BE BACKED-UP.   PRESS
RETURN  AND  THEN  TYPE IN THE LAST TRACK TO BE  BACKED-UP  WITH  THE  CURRENT
ADDRESS  MARKER SETTING.   IF THE TRACKS IN THE SPECIFIED RANGE ARE NOT SPACED
AT  1  TRACK INTERVALS,  ENTER THE INTERVAL AT THE 'TRACK  INCREMENT'  PROMPT.
PRESS RETURN FOR THE FOLLOWING QUESTIONS AND BEGIN THE BACKUP AFTER  INSERTING
THE DISKS WHEN PROMPTED.   WHEN YOU RETURN TO THE MAIN MENU,  REPEAT THE ABOVE
PROCEDURE  FOR EACH RANGE OF TRACKS WHICH CONTAINS A DIFFERENT ADDRESS MARKER.
     NOW COMES THE MOMENT OF TRUTH!  TRY TO BOOT UP THE BACKED-UP DISK (IF THE
ORIGINAL  HAD A WRITE-PROTECT TAB,  THE BACK-UP SHOULD TOO!).   IF THE  BACKUP
BOOTS, THEN ALL WENT SUCCESFULLY.

STEP 3:
     IF THE BACK-UP DID NOT WORK PROPERLY THEN THERE ARE A FEW THINGS TO  LOOK
FOR.

1....DID  ALL  OF THE TRACKS WHICH SHOULD HAVE BACKED-UP DO SO?   THIS CAN  BE
     SEEN  WHILE THE BACK-UP TAKES PLACE AS A 'Y' OR AN 'N' UNDER THAT  TRACKS
     STATUS LOCATION.   IF SOME DID NOT,  THEN THE ADDRESS MARKER WAS PROBABLY
     NOT DETERMINED PROPERLY.   IF THIS IS THE CASE,  THEN GO BACK TO THE  TBE
     AND TRY THOSE TRACKS AGAIN.
2....IF EVERYTHING SEEMED TO GO WELL,  BUT THE BACKUP REFUSES TO WORK (YOU MAY
     WANT  TO TRY THE PROCEDURE AGAIN,  MAYBE WITH THE SOURCE AND  DESTINATION
     DRIVES  REVERSED,  TO  MAKE SURE IT WAS NOT A POWER GLITCH OR OTHER  SUCH
     OCCURANCE  WHICH MESSED THINGS UP) THE NEXT STEP IS TO TRY THE  PROCEDURE
     WITH  THE  'SYNCHRONIZED COPY' OPTION SELECTED.   DISKS  WHICH  USE  THIS
     METHOD  OFTEN  MAKE VIOLENT HEAD MOVEMENTS DURING THEIR  BOOT  PROCEDURE.
     THIS CAN BE A CLUE TO THIS TYPE OF PROTECTION.

ADDITIONAL INFORMATION:
     ON  SOME DOS 3.3 DISKETTES,  THE GAPS BETWEEN THE SECTORS ARE REDUCED  IN
SIZE.   IN  SOME  CASES  THEY  CAN  BE  AS  SMALL  AS  4  OR  5  BYTES.   WHEN
NIBBLES  AWAY ][ FINDS THE BEGINNING OF A SECTION OF DATA,  IT NORMALLY ADDS 8
BYTES  OF SYNC JUST BEFORE THE DATA.   THIS WILL NORMALLY PUT SYNC BYTES  INTO
THE  GAP BEFORE THE DATA,  WHERE IT SHOULD BE.   HOWEVER,  IF A DISK HAS  VERY
SMALL GAPS,  THEN THE ADDED SYNC CAN OVERWRITE THE END OF THE PREVIOUS SECTOR.
THE PARAMETER FIX AMNT CONTROLS THE NUMBER OF SYNC BYTES WHICH ARE  ADDED,  SO
THIS  VALUE  CAN BE REDUCED TO PREVENT ANY DATA FROM BEING  OVERWRITTEN.   THE
VALUE THAT NIBBLES AWAY ][ USES FOR THE SYNC WHICH IT PUTS IN IS CONTAINED  IN
THE  PARAMETER  FIX VALU.   NORMALLY THIS IS A $7F,  BUT IT CAN BE SET TO  ANY
DESIRED VALUE.
    IT  SHOULD BE NOTED THAT NIBBLES AWAY ][ REGARDS ANY DATA BYTE  WHICH  HAS
ITS HIGH BIT CLEARED TO BE A SYNC BYTE.   SO THE $7F WHICH IS NORMALLY IN THIS
PARAMETER MEANS THAT A SYNC $FF IS TO BE ADDED.  IF THE 'OVERIDE STANDARDIZER'
OPTION  IS  SELECTED,  THEN NIBBLES AWAY ][ WILL NOT ADD ANY  BYTES,  IT  WILL
SIMPLY  CONVERT THE DATA WHICH IS PRESENT BEFORE A SECTOR INTO  SYNC,  WITHOUT
CHANGING ITS VALUE.   THIS TECHNIQUE CAN ALSO BE USED FOR DISKS WHOSE GAPS ARE
VERY SMALL.

     ANOTHER  ITEM TO WATCH FOR IS DISKS WHOSE TRACKS APPEAR TO BE VERY  LONG.
SOME DISK PROTECTION SCHEMES PUT GARBAGE ON A PORTION OF THE TRACK.  WHEN THIS
GARBAGE  IS  READ BACK,  MORE BYTES ARE READ IN THAN WERE WRITTEN  OUT.   THIS
CAUSES  THE TRACK TO BE LONGER THAN NORMAL,  AND IN SOME CASES IT  BECOMES  SO
LONG  THAT  THE  DEFAULT PARAMETERS FOR NIBBLES AWAY ][ CANNOT FIND  THE  DATA
PROPERLY.   THE  PARAMETERS  DATA  MIN AND DATA MAX CONTROL  THE  MINUMUM  AND
MAXIMUM TRACK LENGTHS (IN INCREMENTS OF 256 BYTES) WHICH NIBBLES AWAY ][  WILL
ACCOMODATE.   THE  NORMAL VALUE OF DATA MAX IS $1D,  BUT THIS CAN BE SET TO  A
HIGHER VALUE,  SUCH AS $25,  IF A TRACK APPEARS TO BE VERY LONG.   EVEN THOUGH
THE  TRACK  MAY  READ IN AS A LARGE NUMBER OF BYTES,  MANY OF  THESE  WILL  BE
REMOVED BY THE NIBBLE FILTER,  SINCE THEY ARE GARBAGE BYTES.  THIS WILL ASSURE
THAT  THE  AMOUNT OF DATA WRITTEN BACK OUT WILL NOT BE TO LARGE TO FIT ON  THE
DESTINATION TRACK.

     WHEN NIBBLES AWAY ][ FINDS A SECTOR OF DATA, IT LOOKS FORWARD IN THE DATA
TO FIND A SECOND OCCURANCE OF THE SAME PATTERN.   THIS INSURES THAT THE SECTOR
HAS  BEEN READ IN AND LOCATED CORRECTLY.   ON MANY DISKS,  THERE IS A  PRIMARY
SECTION  OF  DATA,  CALLED THE ADDRESS FIELD,  AND THE THE ACTUAL  DATA  FIELD
FOLLOWS.   IN BETWEEN THESE IS A SMALL GAP,  AND MANY TIMES IT CONTAINS RANDOM
INFORMATION.   THIS MEANS THAT NIBBLES AWAY ][ SHOULD ONLY MATCH THE NUMBER OF
BYTES WHICH ARE FOUND IN THE ADDRESS FIELD, SINCE THE BYTES IN THE GAP MAY NOT
READ AS THE SAME VALUE EVERY TIME.  THE PARAMETER FIND MAX CONTROLS THE NUMBER
OF  BYTES WHICH ARE CHECKED DURING THIS PROCEDURE.   THE DEFAULT VALUE OF  $0C
WORKS  IN  MOST CASES,  BUT SOME DISKS USE A SMALLER ADDRESS FIELD  WHICH  MAY
REQUIRE  THIS  PARAMETER  TO BE SET TO A  SMALLER  VALUE.   HOWEVER,  IF  THIS
PARAMETER  IS SET TOO LOW,  THEN NIBBLES AWAY ][ MAY IDENTIFY THE MATCH FOR  A
SECTION OF DATA WHOSE FIRST FEW BYTES ARE THE SAME, BUT WHICH DIFFER LATER ON.
THEREFORE ONE SHOULD EXCERSIZE CAUTION WHEN LOWERING THIS VALUE.
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