Apple II DOS and ProDOS Mini-Manual
Csa2 FAQs-on-Ground file: CSA2DOSMM.TXT rev010
The Csa2 (comp.sys.apple2) usenet newsgroup Frequently Asked
Questions files are compiled by the Ground Apple II site,
1997, 1998.
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____________________________
001- What is a "DOS"?
002- What DOS's are available on Apple II computers?
003- Are there any faster better versions of DOS 3.3?
004- What commands are available in DOS 3.3?
005- How do I use DOS commands from the keyboard? a program?
006- How do I use variables in a DOS command?
007- How do I create new DOS 3.3 diskettes?
008- How much storage space is on a 5.25" diskette?
009- Can I format a DOS 3.3 diskette for just data storage?
010- What is the "Volume Table of Contents" or "VTOC"?
011- Can I assign names to my DOS 3.3 diskettes?
012- What does it mean to "Boot" a disk?
013- What file types does DOS 3.3 have
014- What do the entries in a DOS 3.3 Catalog display mean?
015- Re. DOS 3.3 file names: How long? What characters are legal?
016- How can I use DOS 3.3 to read/write sectors from machine code?
017- How many 'official' versions of DOS 3.3 are there?
018- What information is included in the VTOC?
019- What information is included in a DOS 3.3 Catalog sector?
020- How does DOS 3.3 remember which sectors are used?
021- What are the formats of DOS 3.3's main file types?
022- How can I know a DOS 3.3 prgm is safe to run from hard disk?
023- What are some good DOS 3.3 references?
024- What is ProDOS?
025- What are ProDOS's major features?
026- Which Apple II's can run which versions of ProDOS?
027- How can I create bootable ProDOS diskettes?
028- How do I make a ProDOS disk that will start BASIC?
029- What is the maximum size of a ProDOS volume?
030- How do I LOAD, SAVE, etc. files under ProDOS?
031- What is a "pathname"?
032- What is the default volume and folder when ProDOS boots?
033- How can I set default volume and folder under ProDOS?
034- How can I discover the name of the current default volume?
035- How do I create a folder?
036- How can I access ProDOS routines from machine language?
037- How can I convert DOS 3.3 wares to run under ProDOS?
038- How can I modify ProDOS to do BLOADs to Text Page 1?
039- How can I boot ProDOS on my Franklin computer?
040- What are some good ProDOS references?
From: Rubywand
001- What is a "DOS"?
"DOS" means "Disk Operating System". A DOS is a collection of
machine language routines and data which lets a computer Read and Write
information to/from disk. A DOS also includes commands, such as SAVE and
LOAD, which you can use to create and access files on disk.
Apple II DOS, Commodore 64 DOS, and the DOS used on PC's are all
called "DOS"; but, they are different systems. Their commands are
similar, sometimes identical, because what users want to do with disks
is about the same whatever the computer. However, the way each DOS
arranges and keeps track of data on disk is very different. You will
not, for example, be able to read files from a C-64 diskette on your
Apple II running under DOS 3.3.
--------------------
002- What DOS's are available on Apple II computers?
DOS 3.3 is the first DOS to be widely used on Apple II computers.
Many programs were written to use DOS 3.3 commands and saved on DOS 3.3
diskettes. Apple 'officially' replaced DOS 3.3 with ProDOS back in the
early '80's. However, DOS 3.3 continues to be popular with II users.
Another Apple II DOS is the one introduced with Apple Pascal.
Compared to DOS 3.3 or ProDOS, the Apple Pascal DOS is a very limited,
cumbersome operating system.
-------------------
003- DOS 3.3 seems kind of slow. Are there any faster
better versions of DOS 3.3?
Yes. Today, most "DOS 3.3 users" do not actually use DOS 3.3. Long
ago, Beagle Bros introduced patches which resulted in much better speed,
freed-up extra disk space, and added a CATALOG command which shows
number of Free Sectors. Their ProntoDOS or some modification of it is,
for practical purposes, the "current version" of DOS 3.3.
ES DOS ][ adds a few mods to ProntoDOS. CATALOG shows Free Sectors
and Number of Tracks and it scrolls the entire Catalog (scrolling
stopped by pressing any key) instead of stopping when the screen is
full. ES DOS ][ also lets you use the semi-colon as a terminating
'wildcard' character.
Other popular, higher speed versions of DOS 3.3 include David DOS
and Diversi-DOS; and, there are several small, special-purpose versions
of DOS 3.3. For example, one game maker used RDOS to save space and to
make its diskettes harder to copy.
-----------------------
004- What commands are available in DOS 3.3?
To get very far with "DOS 3.3" you will need the DOS Manual. This
is especially true when it comes to using TEXT files. Other good sources
of DOS 3.3 info include _Beneath Apple DOS_ and _Apple II User's Guide_.
For now, the following is a quickie guide to most Apple II DOS 3.3
commands:
LOAD NARF- loads a BASIC file named NARF.
SAVE NARF- saves current BASIC program in memory as file named NARF.
DELETE NARF - deletes file named NARF
CATALOG - lists contents of diskette to screen
RENAME NARF, NEWNARF - renames file NARF to NEWNARF
RUN NARF- loads and starts a BASIC file named NARF.
BLOAD NARF.PICTURE, A$2000 - loads in a binary file named NARF.PICTURE
starting at address $2000.
note: $2000 is a hexadecimal number ($2000 = 8192 in decimal). DOS
commands can use hex or decimal numbers.
BSAVE NARF, A$300, L$7F - saves $7F bytes of memory starting at address
$300 as a binary file named NARF. (BSAVE NARF, A768, L127 uses decimal
numbers to do the same thing.)
note: The above command statement illustrates typical DOS syntax ...
BSAVE-- the DOS command
NARF-- the file name (the space between the command and file name is
not a requirement; BSAVENARF is okay)
,-- a comma to separate file name from parms which follow
A-- means an Address follows
$300-- the address in hex from which you want to start saving bytes (=
768). Again, spaces do not matter; A768, A 768, A $ 300 are all okay
,-- a comma to separate one parm from another
L-- means a Length follows
$7F-- the length in hex (= 127); this is the number of bytes to be
saved
The command statement says Save $7F bytes, starting at address $300, to
a file named "NARF". NARF will have the bytes found at addresses $300
through $37E.
note: The order of parms following a file name does not matter.
BRUN NARF.DISP, A$1000 - loads in a binary file named NARF.DISP starting
at address $1000 and starts executing machine instructions at address
$1000
LOCK NARF- locks file NARF (indicated by * in a CATALOG). LOCKed files
cannot be deleted, over-written, etc.
UNLOCK NARF - cancels LOCKed status of NARF.
VERIFY NARF - uses checksums to verify that NARF is not a damaged file
MON C, I, O - tells DOS to display Commands, Inputs from disk, Outputs
to disk. You can specify one, two, or all three (e.g. MON C, O etc.).
NOMON C, I, O - cancels all MON requests. NOMON I cancels just the "I"
request.
MAXFILES 7 - sets the number of file buffers to 7. (Upon booting DOS,
the default for the MAXFILES value is 3.)
PR#1 - sets the destination for Apple outputs to the device in Slot 1
(usually a printer). PR# 3 sets it to Slot 3, etc.. PR# 0 sets the
destination back to the display screen.
PR#6 - normally, boots the diskette in Drive 1, Slot 6.
IN# 6 - sets the source for Apple inputs to the device in Slot 6.
IN# 0 - sets the source for Apple inputs to the keyboard (default).
INT - (integer) puts system into Integer BASIC if it is present.
FP - (floating point) puts system into standard Applesoft BASIC.
OPEN NARFOO - prepares to read or write a TEXT file named NARFOO.
READ NARFOO - tells DOS that INPUT and GET statements will obtain
characters from a TEXT file named NARFOO.
WRITE NARFOO - tells DOS that PRINTed characters will go to a TEXT file
named NARFOO.
CLOSE NARFOO - used to terminate access to a TEXT file named NARFOO.
Just CLOSE terminates access to all OPENed TEXT files.
EXEC NARFGO - tells DOS to execute the BASIC and DOS commands found in a
TEXT file named NARFGO
The above TEXT file commands handle 'normal' sequential TEXT files. DOS
can also OPEN, READ, WRITE, ... random access TEXT files. (See DOS
manual.)
Most DOS commands also let you specify Drive and/or Slot. For example
CATALOG, D2 lists the contents of the diskette in Drive 2 to screen.
SAVE NARF,S5,D2 saves NARF to Drive 2 in Slot 5.
NOTE --> Using Drive or Slot parms in a DOS command sets the default
Drive or Slot. So, after CATALOG, D2, a plain LOAD or SAVE will access
Drive 2.
--------------------
005- How do I use DOS commands from the keyboard? ... from
a program?
To use a DOS command from the keyboard, type it in. (A few commands
can be issued only from a program.) To use a DOS command in a program
enclose it in quotes preceded by PRINT CHR$(4). For example:
100 PRINT CHR$(4) "BLOAD NARF, A$2000"
-------------------------
006- How do I use variables, say for file length, in a
DOS command?
Use variables in a command this way:
120 PRINT CHR$(4) "BSAVE NARF, A$2000, L"; NB
Line 120 says that the Length of NARF is the value of variable NB. NB is
used here to represent the number of bytes (in decimal) to be saved.
--------------------------
007- How do I create new DOS 3.3 diskettes?
One of the best features of DOS 3.3 is that any bootable DOS
diskette can create other bootable diskettes.
INIT HELLO - formats one side of the diskette in the currently active
drive, adds DOS, and saves the current program as HELLO.
The program that's automatically placed on the new diskette is the
one in memory when INIT is executed. It is called the "greeting
program" or "hello program" because it is the program which will be run
when the diskette is booted. Usually, the program is named HELLO; but,
you can INIT HOWDY, or any name you like. The hello program can be very
simple, such as ...
100 PRINT CHR$(4) "CATALOG"
110 END
You are free to load in and change the hello program or even delete
it, just like any other. The one restriction is that once a diskette is
INITed, the name of the hello program is fixed for that diskette unless
you use a utility (like Copy II+) to make a change. This is why it's a
good idea to stick with the name HELLO. You will always know what the
hello program's name is.
Once a diskette is INITed it can be used to store your programs and
data files.
-----------------------
008- How much storage space is on a newly
INITialized 5.25" diskette?
A standard DOS 3.3 diskette has 35 Tracks. Each Track contains 16
256-byte Sectors. This gives 35 x 16 x 256 = 143360 bytes per side.
Current versions of DOS 3.3-- e.g. ProntoDOS, etc.-- use Track 0 and
Track 1 plus a sector on Track 2 for DOS; and, Track 17 is used for
holding the Catalog of files and other disk information. This leaves
roughly 130k bytes per side free for your HELLO program and other files.
By the way, when it comes to the way it is stored on-disk, DOS 3.3
is not like the PC's MSDOS or Apple's ProDOS. DOS 3.3 is 'hidden' on
reserved tracks, mainly Tracks 0 and 1. There is no "DOS 3.3" file which
will show up on a CATALOG.
----------------------
009- On my PC I can FORMAT diskettes with or without adding the
operating system. Can I format a DOS 3.3 diskette for just
data storage? -- i.e. without adding DOS or a HELLO program?
Yes. DOS 3.3 does not have a plain "FORMAT" command; but, you can
use utilities such as Copy II+ to easily format a diskette without
adding DOS or a HELLO program.
A format will create 35 Tracks of 16 256-byte sectors each, verify
that each Track is good, and create a 'Contents' and disk info record
called the "Volume Table of Contents" or "VTOC".
----------------------
010- What is the "Volume Table of Contents" or "VTOC"?
The VTOC is a Sector which stores such basic information as Number
of Tracks, Sectors per Track, DOS version, ..., and the 'map' of
used/un-used Sectors. DOS 3.3 writes the VTOC at Track 17, Sector 0.
(For more details on VTOC content see Question 018.)
----------------------
011- Can I assign names to my DOS 3.3 diskettes?
DOS 3.3 has no way to name a diskette "NARF", "DISK 100", "DATA
DISK ", etc. which DOS will recognize. You can, however, 'name' a
diskette by giving it a Volume Number in the range 1-255.
Volume Number is set at the time a diskette is initialized. For
example ...
INIT HELLO, V19
INITs a diskette as Volume 19. If no number is specified, the default
Volume Number used by INIT is 254.
Several DOS commands can specify a Volume Number in order to decide
whether a diskette is the right one for some application.
LOAD NARF, D2, V5 ... for example, will not load NARF from Drive 2
unless the diskette's Volume Number is 5.
A few early pieces of commercial software used Volume numbering;
and, new users often like to Volume number their diskettes. In practice,
this turns out to be a bad idea. A diskette with any Volume Number
except the default (254) is often difficult to work with via standard
utilities. Also, once a diskette is INITed for a certain Volume Number,
changing the number is difficult because Volume Number is embedded in
each Sector. (i.e. You'll end up having to copy every file to another
diskette and, then, re-INITing the source diskette to the new Volume
Number.)
Besides, there's an easy way to give descriptive names to your DOS
3.3 diskettes which will not interfer with normal access. Just write the
name ("GAMES DISK ONE", or whatever) to a Text file named, say,
"DISK.ID".
DOS 3.3 will not know about the name or show it in a CATALOG.
However, your programs will be able to find out the name by just reading
DISK.ID.
-----------------------------
012- What does it mean to "Boot" a disk?
BOOT comes from the idea of 'pulling yourself up by your
bootstraps'. The Apple II disk controller ROM has just enough smarts to
load-in DOS's Bootstrap Loader from Track 0, Sector 0 (it comes in at
address $800 ...).
The Loader loads in a still smarter, bigger routine from several
sectors of Track 0. This routine is the one which loads in the rest of
DOS, moves it to the proper place in memory, and ends up going to DOS's
Cold Start routine. Finally, the hello program is loaded and executed.
--------------------------------
013- What file types does DOS 3.3 have and how is file
type information saved in the Catalog?
In a DOS 3.3 Catalog sector, the third byte in each file's entry
tells the type of the file:
Byte Value* File Type
00 Text
01 Integer BASIC
02 AppleSoft BASIC
04 Binary
08 S type
10 R: Relocatable object module
20 new A type
40 new B type
*DOS 3.3 sets bit 7 of the byte if the file is locked. (e.g. 84 --> a
locked Binary file)
Type R files show up in just a few applications. An R file begins
with 6 bytes which a "loader" routine can use to tell the Target
location of file contents, How many bytes to move, and Source location
to move from.
Although S, new A, and new B are included, no official application
was defined for them and no DOS commands were created to make any
special use of these files.
---------------------
from David Empson
There was an "R" type relocating loader included with the toolkit
for use with BASIC programs and relocatable routines being loaded into
upper memory.
"S" was used by some programs for a generic image file, or something
that was not likely to be touchable with normal code.
The LISA assembler used the second "B" type for its source files.
It had a patched version of DOS that changed the file type list to read
"LARSBAIT", so the source files appeared in the catalog as "L" if you
booted LISA, or "B" if you booted a normal disk.
The "B", "A", "R" and "S" special file types cannot be accessed by
BASIC programs (unless you patch DOS) - commands are only provided for
dealing with "B", "A", "I" and "T" files.
The four special types can only be accessed using direct calls to
the File Manager.
___________________________
from Dave Althoff, Jr.
014- What do the entries in a DOS 3.3 Catalog display mean?
A standard DOS 3.3 Catalog display looks something like this:
DISK VOLUME 254
*A 002 HELLO
B 033 TETRA/SOFT LOGO.BIN
T 142 DAVE'S LIST OF DOS COMMANDS
I 002 INTEGER BASIC PROGRAM
^^ ^^^ ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|| ||| ||||||||||||||||||||||||||||||
|| ||| |___________________________________Filename
|| |_______________________________________File length (in Sectors)
||_________________________________________File type
|________________________________________* means the file is locked
-----------------------------
015- How long can a DOS 3.3 file name be and what characters
can it include?
DOS 3.3 filenames may be up to 30 characters long, and must conform
to the following restrictions:
a. The first character must have an ASCII code value greater than 63.
This excludes numerals, SPACE, and most punctuation. The "@" character
is allowed as well as letters, and some special chars such as "]", "~",
"_", and a few others.
b. Commas and colons may not be used at all. Apart from these
restrictions, anything goes. All kinds of characters, including
uppercase, lowercase, numbers, symbols, and CONTROL characters can be
used after the first character.
____________________________
from Andy McFadden
016- How can I use DOS 3.3 to read and write sectors from
machine code?
DOS 3.3 works like this:
JSR $3E3 ;get address of RWTS IOB (low in Y, high in A)
(you can either change the stuff that Y/A point to, or set up
your own IOB and skip the call to $3E3)
JSR $3D9 ;call RWTS (with IOB address in Y/A)
The IOB (Input/Output Block) is small but non-trivial. Here's what
Beneath Apple DOS says:
$00 table type (always $01)
$01 slot *16
$02 drive (1 or 2)
$03 volume expected ($00 for any)
$04 track ($0-$22)
$05 sector ($0-$0f)
$06-07 address (lo/hi) of the Device Characteristics Table
$08-09 address (lo/hi) of the 256 byte buffer for read/write
$0A not used
$0B byte count for partial sector ($00 for 256 bytes)
$0C command code (0=seek, 1=read, 2=write, 4=format)
$0D return code (carry set on error):
$00 = no errors
$08 = error during initialization
$10 = write protect error
$20 = volume mismatch error
$40 = drive error
$80 = read error (obsolete)
$0E volume number of last access (must be initialized)
$0F slot number of last access *16 (must be initialized)
$10 drive number of last access (must be initialized)
Device characteristics table:
$00 device type (should be $00 for DiskII)
$01 phases per track (should be $01 for DiskII)
$02-03 motor on time count (should be $EFD8 for DiskII)
NOTE: RWTS uses zero-page location $48, which is also used by the Apple
monitor to hold the P-register value. Location $48 should be set to
zero after each call to RWTS.
________________
From: Edhel Iaur, Esq.
017- How many 'official' versions of DOS 3.3 are there
and how can I tell which is running?
According to The Dostalk Scrapbook, there are 3 official (as in
Apple made 'em, I think) versions of DOS 3.3. PEEK (46725) supposedly
tells you which is running:
165:oldest
186:better
182:latest
I remember one had something to do with the way text files are
handled.
---------------------
From: Dave Althoff
The third version then would be the ][e release which contains yet
another APPEND patch, and an additional bit of code which shuts off the
80-column firmware during boot. That version comes on a new System
Master which uses the LOADER.OBJ0 program to fast-load INTBASIC (or
FPBASIC), and a revised "HELLO" program which displays the "MAKE SURE
CAPS LOCK IS DOWN" reminder on a ][e.
_____________________
From: Neil Parker
018- What information is included in the VTOC?
On track 17 ($11 in hexadecimal) sector 0, you will find the Volume
Table of Contents (VTOC). This is the key sector from which all searches
start out.
Format of VTOC:
Byte Meaning
---- -------
$00 Unused (always $04 on my disks)
$01 Track number of first catalog sector
$02 Sector number of first catalog sector
$03 DOS version number ($03 for DOS 3.3)
$04-05 Unused
$06 Volume number ($01-$FE)
$07-26 Unused
$27 Number of track/sector pairs in a track/sector list (always
$7A on normal disks)
$28-2F Unused
$30 Last track where sectors were allocated
$31 Direction of allocation ($01=inward, $FF=outward)
$32-33 Unused
$34 Number of tracks per disk (normally $23)
$35 Number of sectors per track (normally $10)
$36-37 Number of bytes per sector (normally $0100)
$38-3B Bit map for track 0
$3C-3F Bit map for track 1
....
$C0-C3 Bit map for track $22
$C4-FF Unused on normal disks (may contain extra bit maps on disks
with more than 35 tracks)
Bit map format:
Byte 0 Byte 1 Byte 2 Byte 3
FEDC BA98 7654 3210 ........ ........
A 1-bit in any bit position indicates that the corresponding sector
is free. Bytes 2 and 3 in the bit map are always $00 on normal disks.
Bytes 1 and 2 in the VTOC point to the first catalog sector. On
most disks, the first catalog sector is track $11 sector $0F, and
subsequent catalog sectors occupy track $11 sector $0E, track $11 sector
$0D, and so on down to track $11 sector $01. However, DOS 3.3 doesn't
really care where the catalog sectors are or how many there are, as long
as there is a pointer to the first one in the VTOC. (Note, however,
that some utilities, such as Copy II Plus, DO care, and will get lost if
the catalog isn't in its normal position and exactly 15 sectors long.)
---------------------------------
019- What information is included in a DOS 3.3 Catalog
sector and how is it organized?
Each catalog sector contains a pointer to the next catalog sector,
and seven file entries. The format of a catalog sector is as follows:
Byte Meaning
---- -------
$00 Unused
$01 Track number of next catalog sector ($00 if no more)
$02 Sector number of next catalog sector ($00 if no more)
$03-0A Unused
$0B-2D First file entry
$2E-50 Second file entry
$51-73 Third file entry
$74-96 Fourth file entry
$97-B9 Fifth file entry
$BA-DC Sixth file entry
$DD-FF Seventh file entry
Each file entry looks like this:
Byte Meaning
---- -------
$00 Track number of this file's first track/sector list
$01 Sector number of this file's first track/sector list
$02 File type:
Bit Meaning
--- -------
7 0=unlocked, 1=locked
6-0 File type ($00=Text, $01=Integer, $02=Applesoft,
$04=Binary, $08=S, $10=Relocatable, $20=A, $40=B)
$03-20 File name (high bits set; padded with blanks on right)
$21-22 Number of sectors allocated to this file
----------------------------
020- How does DOS 3.3 remember which sectors
are used to store a file?
Every file has a set of one or more "track/sector lists". A
track/sector list lists sectors (by track and sector number) which make
up the file. Each track/sector list points to up to 122 data sectors;
if the file is too long for one track/sector list, a second one is
allocated, and a pointer to it is stored in the first one. Likewise, if
the file is too long for two track/sector lists, a third is allocated,
and so on.
Note that DOS 3.3 supports "sparse" files...there may 0/0 pairs in
the track/sector list indicating parts of the file that were never
written. When DOS 3.3 is reading a file and encounters a 0/0 pair in the
track/sector list, it passes a buffer full of binary zeros back to the
calling program.
A track/sector list looks like this:
Byte Meaning
---- -------
$00 Unused
$01 Track number of next track/sector list sect ($00 if no more)
$02 Sector number of next track/sector list sect ($00 if no more)
$03-04 Unused
$05-06 Sector number in file of first sector number represented in
this track/sector list sector (0 ($0000) for first T/S
sector, 122 ($007A) for second, 244 ($00F4) for third, etc.)
$07-0B Unused
$0C Track number of 0th (or 122nd, or 244th...) sector
$0D Sector number of 0th (or 122nd, or 244th...) sector
$0E Track number of 1st (or 123rd, or 245th...) sector
$0F Sector number of 1st (or 123rd, or 245th...) sector
....
$FE Track number of 121st (or 243rd, or 365th...) sector
$FF Sector number of 121st (or 243rd, or 365th...) sector
---------------------------
021- What are the formats of DOS 3.3's main file types?
A machine-language program is free to store whatever it wants in
any file, but most programs (including DOS 3.3's own command
interpreter) expect the data in each type of file to conform to certain
formats:
A sequential text file consists of lines of ASCII text separated by
carriage returns, and ending with a $00 byte. The high bit of each
character (except the $00 at the end) is set.
A random-access file may be thought of as a set of "mini sequential
access files" separated by strings of $00 bytes. Each "mini-file"
begins at a file position which is a multiple of the random-access
record length.
(Note that sequential and random-access text files share the same
file type. It is up to individual programs to know whether their data
files are sequential or random-access.)
Applesoft and Integer BASIC files have the following format:
Byte Meaning
---- -------
$00-01 Length of tokenized BASIC program
$02-end Tokenized BASIC program
Binary files have the following format:
Byte Meaning
---- -------
$00-01 Load address
$02-03 Length of binary image
$04-end Binary image
A Relocatable file contains the image of a program, followed by a
relocation dictionary containing the information necessary to relocate
the program to an arbitrary memory location. The file format is as
follows:
Byte Meaning
---- -------
$00-01 Original program load address
$02-03 File length (program image + relocation dictionary)
$04-05 Length of program image alone (not including relocation
dictionary)
$06-xx Program image
$xx-yy Relocation dictionary
(The format of the relocation dictionary is a bit too complex to
describe here. I can provide details if anybody's interested.)
The other three file types (S, A, and B) have never been
consistantly defined by anybody. Several programs use these file types
(especially type S) to store their private data files, but there doesn't
seem to be any agreement on their internal format.
For further information I recommend the book "Beneath Apple DOS" by
Don Worth and Pieter Lechner.
P.S. By the way, all two-byte fields in the above are stored in normal
Apple II byte order, low byte first.
______________________________
From: Rubywand
022- How can I tell which DOS 3.3 programs are safe to run
from my GS hard disk using utilities such as
Dos 3.3 Launcher?
So long as a DOS 3.3 program uses only standard SAVE, etc. commands
to write to disk, it will, most likely, pose no dangers running under
Dos 3.3 Launcher from your GS hard disk. Your main concern is making
sure that the software not do special, non-standard direct writes to
disk.
An example of destructive direct-writing is a machine language
routine which dumps game High Scores to a specially formatted 4096-byte
block. Another example is a routine which assumes that certain tracks
are open for caching data. Such actions could mess up formatting,
over-write directories, and do other bad things to files on hard disk.
First, you probably know enough about your own programs to say
whether or not any of them do direct writes. If all disk I/O is via the
usual DOS commands (like SAVE), then you are not doing any direct
writes.
Non-commercial programs which have no reason to store information,
like simple arcades with no High Scores record or Game Save, are
unlikely to write anything directly to disk. One check is to
write-protect the diskette and play the game. If it does not bomb or do
a lot of clattering while attempting a disk access, it probably does not
attempt any direct writes.
Another fairly good check is to list the program (if it's in BASIC)
under Program Writer and Search for any CALLs and & routines. If all
CALLs are to monitor routines ($F800 or higher); and, you can account
for any & commands (e.g. they play music, etc.); and, any expected Game
Saves, Pic Saves, etc. are accounted for by standard DOS 3.3 commands,
then, there are probably no direct writes.
If, via the above checks, a program seems free of direct writes
except for CALLs to the $300 area, then, you will need to account for
these CALLS. Often, they will be for sound effects, special
screen-clears, and/or KB-input processing.
Via the above checks, quite a few programs will seem free of direct
writes except for CALLs to code BLOADed somewhere before or after the
program. You will need to account for these CALLs.
Any program which does CALLs to the Text Page area ($400-$700) is
very suspect as is any program which does CALLs and/or PEEKs and POKEs
to addresses which fall inside the range occupied by the program.
Any program you cannot list and which saves information to disk is
suspect. This includes any games, word processors, and educational wares
which save scores, record position of an adventure party, maintain a
progress record, do document backups, etc..
Any program with REMs filled with 'garbage'-- evidence of hidden
lines-- or which otherwise seems to behave oddly when listed is suspect.
Any commercial program, especially games, educational programs, and
word processors, and any supposedly deprotected commercial program is
suspect.
Any program which automatically reboots upon a Reset is very
suspect.
About the only way to verify that some "suspect" program does not
do direct writes is go to the monitor and account for the functions of
machine code routines. Just noting than no JMPs or JSR's go to the usual
DOS locations does not protect against custom disk R/W routines which
can be located in all sorts of places.
Note: If code is in the Text Page or any other area which is
automatically changed when the program is halted, you will need custom
firmware to do an auto-move of these areas upon Reset. In fact, you may
need to check such areas at different times in the game, etc..
One alternative to a special auto-move is to look for and view the code
that you believe is going into the Text Page, etc. on diskette using a
utility like the Copy ][+ Sector Editor. This does not, however,
guarantee that the code is not greatly modified after being loaded by
the program.
If any of the above conveys the impression that some wares are
trapped specifically in order to mess up disks of users who copy or in
any way modify the wares, it is because this is the case. Many other
wares do direct writes in order to speed-up game play, make a word
processor's operation more 'transparent' and user-friendly, and for
other good reasons. There are, in short, lots of DOS 3.3 'icebergs'
waiting to sink your hard disk.
So; if you did not write a DOS 3.3 program yourself or do not have
some guarantee from the program's producer or an experienced user of the
program on hard disk, then, either list the program and check the code
or forget about launching it from hard disk.
-------------------------
023- What are some good DOS 3.3 references?
DOS Books
The DOS Manual from Apple
Beneath Apple DOS by Worth & Lechner
Apple II User's Guide by Poole, Martin, and Cook
=============================
024- What is ProDOS?
ProDOS
ProDOS is the official Apple ][ DOS which came after DOS 3.3. Do
not confuse "ProDOS" and "ProntoDOS". ProntoDOS is a slightly modified
DOS 3.3 which provides much faster disk I/O than standard DOS 3.3.
ProDOS is a whole new disk operating system.
----------------------------
025- What are ProDOS's major features?
ProDOS has lots of nice features-- mainly, you can create
sub-directories, diskettes ("volumes") can be named, and ProDOS works
well on hard disks. The GS System 6 Finder can handle ProDOS files and
launch programs from ProDOS diskettes. ProDOS's BASIC command
interpreter shares many commands with DOS 3.3, too; so, it is not
difficult for DOS 3.3 users to get started with the newer operating
system.
____________________________
From: David Empson
026- Which Apple II's can run which versions of ProDOS?
All Apple II's, from the 64k Apple II+ through the IIgs, can run
versions of ProDOS up through version 1.9. (A 48K II+ can also run
ProDOS 1.0 or 1.0.1, but this isn't very useful as there are few
applications that will work in this environment.)
Versions 2.x.x require an Apple II equipped with a 65C02, 65C802,
or 65C816 such as an Apple IIe-enhanced, //c, IIc+, or IIgs.
____________________________
From: Rubywand
027- How can I create bootable ProDOS diskettes?
Creating bootable ProDOS diskettes is a bit more bother because,
unlike DOS 3.3, ProDOS is not automatically written to protected sectors
on the diskette via an INIT command. (ProDOS does not have an INIT
command.) Instead, ProDOS is in a file on the diskette and so is the
ProDOS 'connection' to BASIC, called BASIC.SYSTEM.
To make new bootable ProDOS diskettes, the easiest approach is to
use Disk Muncher or some other whole-disk copier to just copy a bootable
ProDOS diskette. You can delete the files you don't want from the copy.
Another option is to use Copy II+ (a ProDOS version) to FORMAT a
ProDOS diskette. (FORMAT writes blank tracks so that the diskette can be
used to hold files.) Then, copy BASIC.SYSTEM and PRODOS to the new
diskette. On a IIgs, all of these operations are easily handled via the
Finder.
Note: If you want to copy ProDOS from GS/OS, copy the file P8 from the
SYSTEM/ folder and rename it to "PRODOS" on your diskette.
------------------------
028- How do I make a ProDOS disk that will start BASIC?
If you want ProDOS to boot and start a BASIC program, then both
PRODOS and BASIC.SYSTEM must be present. (BASIC.SYSTEM should be the
first .SYSTEM file on the diskette.) The "hello" program on a ProDOS
diskette is named "STARTUP". This is the program which will be run upon
booting the diskette. (If there is no "STARTUP" program, you will end
up at the usual BASIC prompt after booting.)
A simple STARTUP program you can type in and save to your new
ProDOS diskette is ...
10 TEXT: HOME
20 PRINT CHR$(4)"CAT"
30 END
After typing in the program, just enter SAVE STARTUP. Next time you
boot the diskette, the above program will run and the diskette's CATALOG
will be displayed.
A good ready-made STARTUP program and program selector for
launching ProDOS 8 programs on a IIgs is available on Ground as
speedgs.shk. The file unShrinks to the Startup program and a Readme
directions file. You can find speedgs.shk in the 1WSW collection at ...
ftp://ground.ecn.uiowa.edu/2/apple2/Collections/1WSW/
________________________
From: David Empson
029- What is the maximum size of a ProDOS volume?
When a diskette is formatted for ProDOS it is given a name by the
user. A ProDOS diskette is also called a "volume". A ProDOS hard disk
will, usually, be partitioned into two or more named volumes. The
maximum size of a ProDOS volume is 32767.5 kilobytes (65535 blocks).
________________________
From: Rubywand
030- How do I LOAD, SAVE, etc. files under ProDOS?
LOAD (SAVE, RENAME, etc.) work very much as in DOS 3.3.; so, you
can use Slot and Drive parms to specify the target volume. However, to
get the most from ProDOS you will usually be working with volume names
and folders. (or, "directories").
If GAME3.PIC is a binary file in a directory named "PICS" on a
volume named "NARF", you could load it into memory starting at address
$2000 via
BLOAD /NARF/PICS/GAME3.PIC,A$2000
or, in BASIC
100 PRINT CHR$(4)"BLOAD /NARF/PICS/GAME3.PIC,A$2000"
So, in ProDOS, you can access a disk (or volume) by name ...
RUN /GAMES/CHINA.SEA
will find the disk (volume) named "GAMES", then, find, load, and run
CHINA.SEA.
You can, also, refer to a disk by its location ...
CAT,S6,D1
will do a short-form catalog of the main directory of the diskette in
DRIVE 1 connected to SLOT 6.
-----------------------
031- What is a "pathname"?
Suppose the file BARDS2.PIC is in the folder PICS on the diskette
(volume) named "NARF". Then ...
/NARF/PICS/BARDS2.PIC is BARDS2.PIC's complete "pathname".
/NARF/PICS/ is a "pathname prefix" for all files in the PICS
directory on the volume named "NARF".
A leading "/" indicates a volume name (/NARF).
The "main directory" or "root directory" is the one in which the
files PRODOS and BASIC.SYSTEM (along with any other files the user wants
there) are usually located on a ProDOS diskette. NARF's main directory
pathname prefix is just /NARF/.
-----------------------
032- What is the default volume and folder when
ProDOS boots?
When ProDOS boots, it will assume that LOADs, SAVEs, etc. refer to
the main directory of the volume from which it was booted. For example,
if NARF is booted and JOYSTICK.TEST is a program in NARF's main
directory, then
RUN JOYSTICK.TEST
will run the program. There is no need to enter RUN /NARF/JOYSTICK.TEST
.
------------------------
033- How can I set default volume and folder
(directory) under ProDOS?
The ProDOS PREFIX command lets you set the volume and folder (or
directory) .
For example,
PREFIX /NARF
sets the current default directory to the main directory of the disk (or
volume) named "NARF".
PREFIX /NARF
also sets the default drive (that is, defaults for SLOT and DRIVE) to
that in which the volume named NARF is located. Usually, the user does
not notice or care about this feature since the location of a volume
does not, usually, change during a session. However, it _may_ change, as
when a user is swapping-in diskettes among two or three drives. If this
happens, ProDOS will look for the diskette.
To set the default folder without changing volume, you can use the
PREFIX command without a leading "/". For example, if the current
default volume is /NARF and NARF's main directory is the default
directory, then
PREFIX PICS
sets the current (default) directory to PICS. The default pathname
prefix would be /NARF/PICS/. Of course,
PREFIX /NARF/PICS
is also a legal command.
----------------------
From: David Empson
PREFIX /
reverts to the default behaviour of using the root directory of the
default drive, and the slot/drive options can be used to change disks,
as with DOS 3.3.
______________________
From: Rubywand
034- How can I discover the name of the current
default volume?
A program can discover the name of a disk (or volume) in the
current default drive as follows:
100 PRINT CHR$(4)"PREFIX": INPUT"";P$
The volume name will be saved in P$. This command is often employed
after booting to discover the volume name. Line 100 also sets the
default directory PREFIX to match the name of the disk (or volume) it
finds.
______________________
From: David Wilson
035- How do I create a folder?
Creating folders (or directories) is the one time you do not need
to provide a type parameter (e.g. TDIR) for the CREATE command. Hence
CREATE GIFPICS
would create a folder named "GIFPICS" in the current default directory.
______________________
From: Neil Parker
036- How do I access ProDOS routines from machine language?
There are 26 different functions that can be performed through the
ProDOS machine-language interface (MLI), and each one takes its own
unique parameter list. That's far more typing that I'm willing to do
tonight, but the information below should at least give a taste of
what's available. For more information, you might want to check out your
local used bookstores for old Apple ProDOS manuals, or for some of the
third-party books that used to be available (I don't even have Apple's
ProDOS manuals-- I get by just fine with _Beneath_Apple_ProDOS_ by Don
Worth and Pieter Lechner, and _Exploring_Apple_GS/OS_and_ProDOS_8_ by
Gary B. Little).
Machine-language programs call ProDOS by doing a JSR to $BF00. This
entry point is called the machine-language interface, or MLI, and it's
responsible for carrying out almost all of the functions tha ProDOS can
perform.
To determine what function to perform, ProDOS examines the byte
immediately following the JSR instruction. Immediately after the
command byte come two more bytes that point to the command's parameter
list. When the call completes, it returns to the code immediately
following the parameter list pointer. Thus, a ProDOS call looks like
this:
MLI EQU $BF00
JSR MLI
DB COMMAND_CODE
DW PARAM_LIST
BCS ERROR
The MLI returns with the carry flag set if an error occurred (hence the
"BCS ERROR" instruction in this example), and an error code in the
accumulator.
There are 26 command codes available:
$40 ALLOC_INT Set up an interrupt handler
$41 DEALLOC_INT Remove an interrupt handler
$65 QUIT Exit the current program; run prgm launcher
$80 READ_BLOCK Read a block from a device
$81 WRITE_BLOCK Write a block to a device
$82 GET_TIME Get the time from a clock card (if any)
$C0 CREATE Create a new file
$C1 DESTROY Delete a file
$C2 RENAME Rename a file
$C3 SET_FILE_INFO Change a file's charateristics
$C4 GET_FILE_INFO Get a file's characteristics
$C5 ONLINE Find the name of a disk in a drive
$C6 SET_PREFIX Set prefix to be added to partial pathnames
$C7 GET_PREFIX Get the current prefix
$C8 OPEN Open an existing file for I/O
$C9 NEWLINE Set line-terminator character for an open file
$CA READ Read data from an open file
$CB WRITE Write data to an open file
$CC CLOSE Close an open file
$CD FLUSH Flush file's block buffer to disk; don't close
$CE SET_MARK Set the current file position
$CF GET_MARK Get the current file position
$D0 SET_EOF Set the length of a file
$D1 GET_EOF Get the length of a file
$D2 SET_BUF Set the location of an open file's blk buffer
$D3 GET_BUF Get the location of an open file's blk buffer
Each call expects a different parameter list. Like I said earlier, the
list of parameter lists is too long for me to type in tonight. But I
can include a couple of examples...here's how to rename a file, for
example:
JSR $BF00
DB $C2 ; $C2 = RENAME
DW REN_PARMS
BCS ERROR
REN_PARMS DB 2 ; RENAME parm list contains 2 parms
DW OLD_NAME ; 1st parm is ptr to old name
DW NEW_NAME ; 2ns parm is ptr to new nme
OLD_NAME DB 8,"OLD.NAME" ; (name is count byte followed by ASCII chars)
NEW_NAME DB 8,"NEW.NAME"
And here's how to quit from a program and return to the ProDOS program
selector:
JSR $BF00
DB $65 ; $65 = QUIT
DW QUIT_PARMS
BRK ; (QUIT doesn't return)
QUIT_PARMS DB 4 ; QUIT parm list contains 4 parms
DB 0 ; All 4 parms normally null
DW 0
DB 0
DW 0
_______________________
From: Rubywand
037- How can I convert DOS 3.3 wares to run under ProDOS?
Quite a few DOS 3.3 programs will run fine under ProDOS with no
change at all. Unless you have some reason to believe a DOS 3.3 program
will not run under ProDOS, it's worthwhile to just copy it to a ProDOS
diskette and give it a try. Since DOS 3.3 programs which do direct
writes can, possibly, damage a ProDOS disk (see Question 22), be sure to
run any risky-looking tests from a booted ProDOS diskette for which you
have a backup.
The main barriers to running DOS 3.3 programs under ProDOS are ...
1. Size: DOS 3.3 leaves more space for programs than ProDOS +
BASIC.SYSTEM. Some DOS 3.3 programs are too large for ProDOS. To use
them you will need to find ways to reduce program size.
2. Areas of memory used: ProDOS reserves parts of memory, such as Text
Page 1 ($0400-$07FF), for various pointers. Some DOS 3.3 programs LOAD
or BLOAD into one or more of these areas. For example, some games BLOAD
a lo-res pic or Text for you to look at while the rest of the game
loads. Normally, ProDOS will refuse to do such loads and the result will
be a BUFFERS NOT AVAILABLE error message. To run these programs you will
need to unmark the reserved areas which get in the way and/or change the
location(s) of the program's troublesome LOADs and BLOADs.
When ProDOS loads it uses most of the memory in the "language card"
areas. Some DOS 3.3 programs also use this memory. If a DOS 3.3 program
uses the "language card" it will probably have to be modified in order
to run under ProDOS.
ProDOS handles buffer allocation differently than DOS. If a DOS 3.3
program lowers HIMEM in order to create space for BLOADing code or data,
it may need to be modified to guarantee that the code/area is safe. (See
page 237 of Exploring Apple GS/OS and ProDOS 8 or page 7-4 of Beneath
Apple ProDOS.)
3. Names: DOS 3.3 file names can be longer and have more kinds of
characters than ProDOS names. If a DOS 3.3. program BLOADs, WRITEs, etc.
to any files, you will need to be sure that the file names used are
compatible with ProDOS.
4. DOS/ProDOS Commands and Syntax: There are, really, very few DOS 3.3
command and syntax differences likely to cause problems under ProDOS.
Still, there are some and you will need to check for these and make any
indicated mods.
5. Integer BASIC: Int BASIC programs can be transferred to a ProDOS
diskette; but, you can not run them directly under ProDOS. If you are
willing to move an Int BASIC program to a Text editor, convert the
syntax to Applesoft BASIC, and EXEC the resulting Text file, you can
obtain an Applesoft BASIC program which you can modify as necessary for
ProDOS.
6. It's not DOS 3.3: Very old software, old commercial copy-protected
software, and deprotected copies of old software may not be on DOS 3.3
disks. Your first challenge with such software is getting it into a form
which will permit transferring files to a ProDOS diskette.
When checking and modifying a DOS 3.3 program for ProDOS a good
program editor is essential. You will save untold hours of work when you
invest in Beagle's tried and true "Program Writer".
_________________________
From: Jeff Blakeney
038- How can I modify ProDOS to do BLOADs in the input buffer
and Text Page 1 areas?
You can use a POKE 48984,192 to modify the bit map. This protects
pages $00 and $01, and unprotects pages $02-$07.
Note: Because the firmware and I/O cards make use of the "screen hole"
bytes in the $0400-$7FF area, BLOADing over these can interfere with
some devices.
For this reason, it is best to have special DOS wares on a separate
ProDOS diskette with a STARTUP program which does the POKE 48984,192.
This way you will know that the system has been changed to run the DOS
wares and not inadvertently try to run a program like Appleworks, etc..
under the modified ProDOS.
-------------------------
From: David Empson
A safer method is to BLOAD the file elsewhere, and copy data onto the
text screen in a loop, copying 120 bytes and skipping 8 bytes, repeated
8 times.
_________________________
From: Rubywand
039- How can I boot ProDOS on my Franklin computer?
In an old Apple Clinic note, Stephen Craft listed specific
locations to change after your Franklin freezes. You could then restart
via a 2000G from the monitor.
It turns out that the bytes Stephen was diddling are D0 03 in the
sequence 69 0B D0 03 A5 0C 60. The sequence is found in all versions of
ProDOS I've checked so far.
To fix the booting problem, try this:
Start Copy II+ and select "Sector Editor"
Swap-in the ProDOS diskette
READ Track 0, Sector 0
Search for (Hex bytes): 69 0B D0 03 A5 0C 60
When you find the above, change the D0 03 to EA EA
and write the changed sector back to diskette.
This patch has no effect on ProDOS functioning on regular Apple
II's. In fact, most users probably have diskettes on which the patch is
already present.
--------------------------
From: David Wilson
The D0 03 branch is at the end of some code that calculates a
checksum of the APPLE ][ string found in all genuine Apple II ROMs.
When I modified my first copy of ProDOS 1.0.1 to run on my
Multitech MPF-III, I simply changed D0 03 in that sequence to D0 00.
This has the same effect as substituting EA EA-- i.e. the routine exits
with the 'checksum is correct' value in register A.
_________________________
From: Rubywand
040- What are some good ProDOS references?
ProDOS Books
ProDOS Technical Reference Manual from Apple (Addison-Wesley)
Beneath Apple ProDOS by Worth & Lechner
Exploring Apple GS/OS and ProDOS 8 by Little
ProDOS Inside and Out by Doms and Weishaar