Documentation For FBAD

    This is the documentation for the program written by SME Systems to 
look for BAD SECTORS on disk drives.


STARTING UP
-----------

	You start the program with the command 'FBAD<cr>'. There are no 
command line options or parameters.


USING
-----

	When the program is run, the screen is cleared and a message 
is displayed on the screen. You are now asked for the 'DISK DRIVE' 
name that you want to check for bad sectors on. If you enter a <cr> only, 
the program will immediately terminate and return you to the operating 
system. Disk drive names can be upper or lower case and are only a SINGLE 
LETTER in the range A..P.

	After selecting a disk drive, the program LOGS IT IN then displays 
the parameters for the disk. These are number of tracks, sectors per track 
etc. This should be checked against what you think the drive is. These 
parameters are used by the program to check the disk and if they are not 
correct, the program will not function correctly.

	NEXT you are asked for a starting block number to check. If you 
enter a <cr> the first block on the disk is checked. This is the default. 
The LAST BLOCK you want to check is then asked for. If you enter a <cr> then 
the last block on the disk is assumed. 

	When the block numbers are entered, the program then quickly scans 
all the sectors on the disk and traps any bad sectors. These are recorded 
into the program and saved for later action.


	When the disk has been checked, the program will offer to display the bad sector numbers. 

	The last step in the process is where the program asks youif you 
want to MARK the bad sectors in the directory. If you answer 'Y' then the 
program will;

1) Erase any copies of existing marker files ('BAD').
2) Scan the directory and create a new 'BAD' file name.
3) Allocate all the bad sectors (in blocks) to the file.
4) Reset the disk system.

	The above actions result in the 'BAD' file being created on the 
disk you are checking and having pointers in it to the bad sectors. In this
way the file takes up storage space that is bad so that other files will
not attempt to use this space.




DEPENDANCIES
------------

	This program has the following dependancies.

1) Only runs with CP/M Plus (3).

2) Will not MARK directories on disks with less capacity than 256 K.

3) Will not mark disks with bad sectors in the directory.



SOURCE CODE
-----------

	FBAD is written in PL/I-80 and uses a large number of assembler 
routines. The following is a list of the files used.



FBAD    .COM	The executable program.
FBAD    .PLI	Source code to the main part of the program
PLIUTIL .REL	Library of assembly routines used by FBAD
PLIUTIL .DCL	PL/I declarations for the assembler library.

	The PLIUTIL.REL file is made up of the following modules.

PLIUTIL .ASM	Main section
RANDOM  .ASM	Random number routine.
PBUFF   .ASM	Print a buffer of 128 bytes routine.
PORT    .ASM	Direct port I/O
DATE    .ASM	Time and Date routine.
PLICOMM .ASM	Common routines in the library.
PUSER   .ASM	User number fetch and support.
CRC     .ASM	CRC routines.
SHIFT   .ASM	Bit string shift routines.
DELFIL  .ASM	File deletion routines.
MAKLIB  .SUB	Submit file to stitch a library back together from REL files.


			--------------------------------

	To generate a new version;

1) Do your mods and re-assemble/compile.

2) Link a new executable version with the command

    link x:fbad,x:pliutil<cr>

       where x is the drive the files are on.





				SME Systems   14-12-84