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Archive-name: apple2/faq/part6
Posting-Frequency: monthly
Last-modified: 2003/10/1
URL: http://home.swbell.net/rubywand/A2FAQs1START.html
The comp.sys.apple2 Usenet newsgroup Apple II FAQs originate from
the Ground Apple II archive, 1997-2003. Administrator: Steve Nelson
Csa2 FAQs-on-Ground ref: Csa2DOSMM.txt rev067 October 2003
DOS & ProDOS
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- How can I find out the address and size of a BLOADed file?
019- What information is included in the VTOC and Catalog sectors?
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 run DOS 3.3 programs from 3.5" disks and hard disk?
023- How can I get DOS 3.3 from the net without an A2 tcom utility?
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 boot and start a BASIC program?
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 volume name of a just booted disk?
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 DOS 3.3 and ProDOS references?
041- How can a BASIC program tell which DOS it's running under?
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. To get DOS 3.3 from the net, see Csa21MAIN4:
Get It- Links to popular software packages.
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. This DOS includes a CATALOG fix to
show correct size of files bigger than 255 sectors.
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.) Below is a chart which compares speed and features for standard and speeded
versions of DOS 3.3.
BLOAD Time Does Large Files Frees 15 Disp Free Error
Test*** INIT CATALOG fix Sectors Sectors Msg
Std DOS 3.3**- 8.9 sec Yes No No No Yes
DavidDOS- 2.8 sec No Yes No Yes Yes
DiversiDOS- 2.9 sec Yes Yes No Yes err#
EsDOS- 2.3 sec Yes Yes Yes Yes abbr*
ProntoDOS v1- 3.0 sec Yes No Yes No Yes
ProntoDOS v2- 3.0 sec Yes No Yes Yes Yes
* abbr: shows abbreviated error messages
** 1980-1983 versions
*** time to BLOAD MUFFIN from the 1983 DOS 3.3 System Master disk
You can get standard and high-speed DOS 3.3's from a number of places on the net.
See Csa21MAIN4: Get It- Links to popular software packages.
-----------------------
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 from which you want to start saving bytes (the $
indicates a hex value; $300= 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 and verify that each
Track is good. Then, it will allocate the Catalog track and create a 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
019.)
----------------------
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 (1980)
186: better (January 1, 1983)
182: latest (?)
I remember one had something to do with the way text files are handled.
---------------------
From: Dave Althoff
The second version would be the IIe release ("DOS 3.3e") 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 "BE SURE CAPS LOCK IS DOWN" reminder on a IIe.
---------------------
From: Rubywand and Olcott
One big problem with DOS 3.3e (and, probably, any later versions) is that it uses
some memory in the DOS area which the 1980 release leaves alone. This means it can not
be safely patched with Beagle's "Prontodos" speed-up mods.
With DOS 3.3e, you get an APPEND patch (which turns out to introduce a new APPEND
bug), a IIe display frill, and a DOS which is _much_ slower than the 1980 DOS 3.3
patched for Prontodos.
_____________________
From: David Empson
018- How can I find out the address and size of a BLOADed
DOS 3.3 file?
After you BLOAD a file, you can use the following command to find out the exact
length of the file you just BLOADed:
PRINT PEEK(43616) + 256 * PEEK(43617)
Use another PEEK to find out where it was loaded:
PRINT PEEK(43634) + 256 * PEEK(43635)
The value displayed is the load address of the binary file.
_____________________
From: Neil Parker and Rubywand
019- What information is included in the DOS 3.3 VTOC and
catalog sectors?
VTOC
The Volume Table of Contents (VTOC) is Sector $00 (0) on Track $11 (17). This is
the key sector from which all searches start out.
Example: A typical DOS 3.3 Disk's VTOC sector
Byte 00 01 02 03 04 05 06 07 08 09 0A 0B 0C 0D 0E
0000- 04 11 0F 03 00 00 FE 00 00 00 00 00 00 00 00
0010- 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
0020- 00 00 00 00 00 00 00 7A 00 00 00 00 00 00 00
0030- 15 01 00 00 23 10 00 01 00 00 00 00 00 00 00
....
0080- 3F 7F 00 00 00 00 00 00 00 00 00 00 00 00 00
....
00F0- 00 00 00 00 00 00 00 7A 00 00 00 00 00 00 00
Byte Meaning
---- -------
$00 Unused (always $04 on my disks)
$01-02 Track/Sector location of first catalog sector-- the standard
location is Track $11/Sector $0F (17/15)
Note: The location of first catalog sector may be different on some
disks. DOS 3.3 can adjust; but, some utilities (e.g. Copy II Plus)
assume T/S $11/$0F and will not be able to find the catalog.
$03 DOS version number ($03 for DOS 3.3)
$04-05 Unused
$06 Volume Number-- $01-$FE (1-254) is the standard range;
$FE (254) is the standard default VN
Note: This entry merely records the VN for handy reference.
VN is set when a disk is INITed and it is embedded in the
Address header of each sector.
$07-26 Unused
$27 Max number of Track/Sector pairs in each sector of
a file's Track/Sector list-- normally $7A (122)
$28-2F Unused
$30 Last track where sectors were allocated-- in the example
it is Track $15 (21)
$31 Direction of allocation-- $01 (+1)=inward; $FF (-1)=outward
$32-33 Unused
$34 Number of tracks per disk-- normally $23 (35)
$35 Number of sectors per track-- normally $10 (16)
$36-37 Number of bytes per sector-- normally $0100 (256)
$38-3B Bit map for Track $00-- four bytes per entry (only two bytes are
used); each bit in the two-byte entry indicates whether a sector
is in use (0) or free for use (1). See example just below.
$3C-3F Bit map for Track $01
....
$80-81 Bit map for Track $12 (18)
Example: The entry shown is 3F 7F 00 00. Only the first two
bytes (3F 7F) are used:
Sector- F E D C B A 9 8 7 6 5 4 3 2 1 0
Bit- 0 0 1 1 1 1 1 1 0 1 1 1 1 1 1 1
Hex- 3 F 7 F
This shows that on Track $12 only sectors $F, $E, and $7 (15, 14,
and 7) are used. The other sectors on the track are free for use.
....
$C0-C3 Bit map for Track $22 (34)-- usually the last track
$C4-FF Unused on normal disks (may contain extra bit maps on disks with
more than 35 tracks)
Catalog
Starting at Track $11/Sector $0F (17/15 in decimal) and working downward in the
track (e.g. Sector $0E, $0D, ...), each catalog sector contains a pointer to the next
catalog sector, and seven file entries:
Byte Meaning
---- -------
$00 Unused
$01 Track number of next catalog sector ($00 if no more)
$02 Sector number of next catalog sector
$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 List sectors. A Track/Sector
List (T/S List) lists sectors (by Track and Sector number) which make up the file.
Each T/S List sector points to up to 122 data sectors If the file is too long for one
T/S List sector, a second one is allocated, and a pointer to it is stored in the first
one, and so on.
Note that DOS 3.3 supports "sparse" files...there may 0/0 pairs in the T/S 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 T/S List, it passes a buffer full of binary zeros
back to the calling program.
A Track/Sector List sector looks like this:
Byte Meaning
---- -------
$00 Unused
$01-02 Track/Sector location of next T/S List sector (00 for Track means
the list uses no more sectors since Track 0 can not be used)
$03-04 Unused
$05-06 Sector number in file (offset) of first sector represented in this
T/S List sector (starting at byte $0C below).
Ex: 00 00 = file sector #0 (i.e. the sector specified is the first
sector in the file). In a second T/S list sector, if required,
the first sector listed would be file sector #122 (i.e. the 123rd
sector) indicated by 7A 00-- hexadecimal $007A = 122 in decimal.
$07-0B Unused
The rest of the T/S List sector lists sectors in which the file is stored ...
$0C-0D Track/Sector location of first sector (in this T/S List sector)
$0E-0F Track/Sector location of second sector (in this T/S List sector)
... etc.
---------------------------
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 (i.e. file contents)
$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 run DOS 3.3 programs from 3.5" disks and hard disk?
You can run quite a few DOS 3.3 programs from 3.5" disk, a large RAM disk, or
hard disk. However, there are numerous DOS 3.3 programs which will not run this way
and which could even damage files and directories on the larger media.
Problems are especially likely when a program modifies and CALLs machine code
routines such as Read/Write Track-Sector (RWTS) and/or makes assumptions about the
physical locations on disk of important DOS 3.3 areas such as the Volume Table of
Contents, CATALOG track, and DOS itself. Using a special routine to save "High Scores"
to a specific Track/Sector is just one of many ways a DOS 3.3 program might create
havoc on a hard disk.
On the other hand, you have programs which stick to using standard DOS commands
from BASIC such as, probably, most of your own DOS 3.3 programs and most 'type-in'
software from publications like SoftSide. Programs like these should run fine using
one of the techniques for accessing DOS 3.3 software from 3.5" diskette or hard disk.
There are two fairly popular approaches to running DOS 3.3 software from 3.5"
diskette on an Apple II. One is to copy it to a specially formatted 3.5" diskette
which boots a modified "DOS 3.3" such as AmDOS or OzDOS. Typically, you get two "400k
disks" on each 3.5" diskette.
A very different approach is used by DOS 3.3 Launcher. It offers two options:
1- You can save some DOS 3.3 programs to ProDOS disk (including 3.5" disk or hard
disk). These must be single-file programs that do not access the disk once they are
loaded into memory. DOS 3.3 Launcher's Copier is used to set launch options.
2- Using the DOS 3.3 Launcher Copier, you can save an entire DOS 3.3 disk as a disk
image to a ProDOS 3.5" diskette, hard disk, etc.. According to 'Launcher's docs:
>> Any disk that uses a standard RWTS (Read/Write Track/Sector) routine can be copied
>> in this manner. This includes not only DOS 3.3 disks, but also many old games which
>> use a standard RWTS, but are not actually DOS 3.3. They can then be launched by DOS
>> 3.3 Launcher, which "boots" the large file directly from your hard disk. <<
To run a program from ProDOS-8, you start DOS 3.3 Launcher from a program
selector such as ProSel-8 which supports the ProDOS 8 startup protocol- - i.e. it can
make applications automatically open a data file. (The DOS 3.3 Launcher docs tell how
to setup a ProSel entry for a program.)
Running a program from the IIgs System Finder is much easier.
>> If you have properly installed DOS 3.3 Launcher, your DOS 3.3 programs should
>> appear with DOS 3.3 icons when viewed through the Finder. To launch them, you
>> simply double click on them, which launches them via ProDOS 8. <<
Of the two basic approaches (a special 3.5" DOS 3.3 or DOS 3.3 Launcher), DOS 3.3
Launcher seems to be the better way to go:
First, it is easy to set up the contents of a DOS 3.3 disk prior to converting it to
disk image form-- you can use any of the popular disk management utilities such as
Copy II Plus. Moving DOS 3.3 files onto an AmDOS or OzDOS disk with the crude FID-type
copiers available is a hassle.
Second, DOS 3.3 Launcher turns out to create and use standard 143,360-byte ProDOS
order (.po) disk images, except, at least on the IIgs, the 'Launcher requires a
special filetype-- e.g. $F1 to run at 1MHz, $F2 to run at "Fast" speed. These
filetypes make it possible for the DOS 3.3 Launcher icons (included) to link images to
the program for easy launching under the Finder-- you just double-click on the image's
icon.
So, you should be able to download any .dsk disk image on your PC, use an
emulator to transfer the contents to a .po disk image, and transfer the .po file via
NULL modem to your Apple II. Here you just need to adjust the filetype for use under
DOS 3.3 Launcher. Or you can convert 5.25" .sdk (shrinked disk) files to .po disk
image form and transfer these via NULL modem.
To download AmDOS, OzDOS, DOS3.3.Launcher, and ProSel, see Csa21MAIN4: Get It-
Links to popular software packages.
-------------------------
023- How can I get DOS 3.3 from the net without an Apple II
telecom utility?
DOS 3.3 Dump is DOS 3.3 in an Apple II Text file. The purpose of the the dump
file (dos33.dmp)is to make it possible for users without DOS 3.3 and without any Apple
II telecom program to obtain DOS 3.3 from the net.
Once you have DOS 3.3, you can obtain ADT and have a way to transfer 5.25" .dsk
disk image files from your net computer to your Apple II. (And once you can transfer
disk images, you can get a good Apple II telecom utility and have a way to transfer
all kinds of files!)
You can find DOS 3.3 Dump along with directions on several net sites. See
Csa21MAIN4: Get It- Links to popular software packages.
=============================
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. To
get ProDOS from the net, see Csa21MAIN4: Get It- Links to popular software packages.
----------------------------
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?
Apple II's from an Apple II+ with 64k RAM through the IIgs can run versions of
ProDOS up through version 1.9 and run Applesoft BASIC programs under these versions.
An older Apple II (with Integer BASIC in ROM) or any Apple II with less than 64k
RAM can run ProDOS 1.0 or 1.0.1 but can not use the ProDOS BASIC interpreter
(BASIC.SYSTEM). This is not a very useful setup as there are few applications that
will work in this environment.
Versions 2.x.x of ProDOS require an Apple II equipped with a 65C02, 65C802, or
65C816 such as an Apple IIe-enhanced, //c, IIc+, or IIgs. The current ProDOS is
version 2.0.3.
____________________________
From: Rubywand
027- How can I create bootable ProDOS diskettes?
Creating bootable ProDOS diskettes is more bother than creating bootable DOS 3.3
diskettes because ProDOS does not have any way to duplicate itself from memory-- i.e.,
it has no INIT command.
One way to make a new bootable ProDOS diskette is to first use Apple's ProDOS
FILER utility or a ProDOS version of Copy II+ to FORMAT a diskette for ProDOS. This
creates tracks filled with blank blocks so that the diskette can be used to hold
ProDOS files. It also writes boot startup code in Blocks 0 and 1 on Track 0.
ProDOS is in a file on a bootable ProDOS disk and so, usually, is the ProDOS
'connection' to BASIC, named "BASIC.SYSTEM". To finish the job you copy BASIC.SYSTEM
and PRODOS from some bootable ProDOS disk to the new diskette.
Another way is to use Disk Muncher or some other whole-disk copier to copy some
bootable ProDOS diskette which includes BASIC.SYSTEM. You can delete any files you
don't want from the copy.
Things are a bit easier on a IIgs running GS System. In the Finder (the usual GS
main 'desktop'), you can insert a blank diskette and let Finder "Initialize" it for
ProDOS. Then you can mouse 'drag and drop' PRODOS and BASIC.SYSTEM from a bootable
ProDOS disk to your new disk. (Or, even easier, if you have a 'stock' blank bootable
ProDOS diskette the same size as your new disk, you can just drag and drop the
bootable disk onto your new disk.)
Note: If you want to copy the ProDOS used by 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 boot and start a BASIC program?
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 as speedgs.shk. The file unShrinks to the Startup
program and a Readme directions file. To get speedgs.shk from the net, see Csa21MAIN4:
Get It- Links to popular software packages.
________________________
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$2000"
So, in ProDOS, you can access a disk (or volume) by name ...
RUN /GAMES/CHINA.SEA
will find the disk (volume) named "GAMES", then, find, load, and run CHINA.SEA.
You can, also, refer to a disk by its location ...
CAT,S6,D1
will do a short-form catalog of the main directory of the diskette in DRIVE 1
connected to SLOT 6.
-----------------------
031- What is a "pathname"?
Suppose the file BARDS2.PIC is in the folder PICS on the diskette (volume) named
"NARF". Then ...
/NARF/PICS/BARDS2.PIC is BARDS2.PIC's complete "pathname".
/NARF/PICS/ is a "pathname prefix" for all files in the PICS directory on the
volume named "NARF".
A leading "/" indicates a volume name (/NARF).
The "main directory" or "root directory" is the one in which the files PRODOS and
BASIC.SYSTEM (along with any other files the user wants there) are usually located on
a ProDOS diskette. NARF's main directory pathname prefix is just /NARF/.
______________________
From: Rubywand and David Empson
032- What is the default volume and folder when ProDOS boots?
When ProDOS boots, it will assume that LOADs, SAVEs, etc. refer to the main
directory of whatever volume is in the boot Slot and Drive. It does not automatically
establish a default volume or folder by name.
So long as no default volume name is set, references to disks by Slot and/or
Drive (e.g. CAT, S6) will set the default device (by Slot and Drive) much as happens
under DOS 3.3.
-----------------------
033- How can I set default volume and folder (directory) under ProDOS?
The ProDOS PREFIX command lets you set the default volume and folder (or
directory). For example,
PREFIX /NARF
or, in a BASIC program
100 PRINT CHR$(4)"PREFIX /NARF"
tells your computer to find the ProDOS volume (e.g. disk, hard disk partition, etc.)
named "NARF" and, once it is found, set the current default directory to the main
directory of the volume named "NARF".
Setting the Prefix eliminates the capability of references by Slot and/or Drive
to set the default device. You can still CAT S6,D2 and execute similar commands
specifying Slot and Drive; but, the "default device" will be the one which happens to
'contain' the volume named "NARF". (That is, when a default volume exists, ProDOS
focuses upon the volume by name and is not very interested in any particular disk
drive.)
Note: References by Slot and/or Drive will, however, still set 'default' Slot and
Drive values. Setting a Prefix just causes these to be ignored as specifiers for the
default volume. (Also, setting a Prefix does not change Slot/Drive defaults.)
Naturally, references to folders on the default volume do not need to specify the
volume name:
CAT GAMES
and
CAT /NARF/GAMES
will both CAT the contents of the folder GAMES located in the main directory of the
default volume NARF.
Note: CAT GAMES/ is also correct. Adding the trailing "/" is generally optional in
commands dealing with folders. To SAVE the game ROBOTS in the above folder, you would
need the "/": SAVE GAMES/ROBOTS . In manuals, etc., folder names are often shown with
the trailing "/" to make it clear that, say, /NARF/GAMES/ refers to a folder and not
to a program named "GAMES" in the main directory of the volume named "NARF".
If there is currently no default volume-- for example, you did not execute the
PREFIX /NARF command from keyboard or a BASIC program-- ProDOS will try to CAT the
GAMES folder on the volume in the default Slot and Drive. As you might expect, some
mixing of Slot and folder name specifiers is allowed. For example:
CAT GAMES,S6,D2
will try to CAT the GAMES folder on the volume in Slot 6, Drive 2.
References such as the above and references to other volumes (e.g. CAT
/PICDISK/HIRESPICS ) do not usually change the Prefix. An exception is the 'plain'
PREFIX command. When used with a Slot parm:
PREFIX,S6,D2
The above command sets default volume to the name of the volume found in Slot 6, Drive
2.
So, running a ProDOS program located in a folder does not automatically 'switch'
all references to files in that folder. If the program expects to use files located in
whatever folder the program resides, either you must set the Prefix to point to the
folder before doing the RUN or the program must set the Prefix. To change the Prefix
to zero-in on a particular folder, you might enter ...
PREFIX GAMES/ACTION
Given that there is a default volume and that it is named "NARF", the above would make
the default place for ProDOS actions the /NARF/GAMES/ACTION folder. If there is
currently no established default volume, ProDOS will look for GAMES/ACTION/ on the
volume in the default Slot and Drive. If it finds the folder, ProDOS will set the
Prefix to the volume name + GAMES/ACTION/ .
To clear (eliminate) recognition of a default Prefix, you can enter ...
PREFIX /
After this command, the default place ProDOS looks for files, etc.. will be the
default Slot and Drive (usually as set by the most recent Slot/Drive reference).
______________________
From: Rubywand
034- How can I discover the volume name of a just booted disk?
You can discover the name of a ProDOS volume in a drive by doing a CAT. The
volume name will be shown at the top of the screen listing (e.g. "/NARF/").
Another way-- one which works in programs as well as from the keyboard-- is to
use the PREFIX command:
PREFIX
This command, when used alone, will normally return one of two results:
o- If there is an established default Prefix (e.g. a default volume has been
specified), then, the result will be the current default Prefix.
o- If there is no established default Prefix, then, the result will be the volume name
of the volume in the default Slot and Drive.
Booting clears any default Prefix and sets default Slot/Drive to the boot drive. For,
say, your STARTUP program to discover the name of the volume on which it resides, it
could execute the following:
100 PRINT CHR$(4)"PREFIX": INPUT"";P$
The volume name of the just booted disk will be saved in P$.
______________________
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?
You use the ProDOS Machine Language Interface (MLI). The MLI is responsible for
carrying out nearly all of the functions (Read Block, Write Block, and 24 others)
which ProDOS can perform.
Machine language programs call ProDOS by doing a JSR to the MLI at $BF00. To
determine which function to perform, ProDOS examines the "command" 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. A ProDOS MLI call looks
something like this:
20 00 BF JSR MLI
80 DB COMMAND_CODE
50 03 DW PARAM_LIST_LOCATION
B0 __ BCS ERROR
In the above, the command code ($80) says "Read a block" and the parameter list is
located at $0350. The MLI call returns with the carry flag set and an error code in
the accumulator if an error occurred; so, a simple error check (the Branch if Carry
Set instruction) is often the next instruction which is executed.
For a detailed description of functions including command codes and parameters,
see a ProDOS manual or one of the other references mentioned in Q&A 040 below.
_______________________
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.
Note: A few 'DOS 3.3' programs, mainly old commercial games, include routines which do
direct writes to one or more sectors. This could overwrite parts of a file or a ProDOS
directory. It's a good idea to copy risky-looking software to a ProDOS disk you can
afford to lose (e.g. a bootable disk with no favorite programs, etc. on it). Boot
this disk and try out the program.
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 (see next
Q&A) 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: Supertimer, Rubywand, David Wilson, Steve Jensen
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. Here
is an updated listing showing the locations to change for several versions of ProDOS:
v1.1.1 $269E: EA EA
v1.4 $282B: EA EA
V1.6 $282B: EA EA
v1.7 $282B: EA EA
v1.8 $2836: EA EA
v1.9 $2865: EA EA
v2.0.3 $2836: EA EA
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 near the end of a routine that checks for the "APPLE
][" string found in all genuine Apple II ROMs but not in most Apple II clone ROMs.
To fix the booting problem, do 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.
The patch eliminates the checksum test/branch and allows ProDOS to boot on Apple
II clones which would normally fail the check. This patch has no effect on ProDOS
functioning on regular Apple II's.
The above patch is absolutely necessary to get a bootable ProDOS working for many
Apple II clones. Jim Sather (inCider, March 1986) recommends a second patch which is
optional. It prevents ProDOS from erroneously reporting that a //e-style 64K 80-column
card is present when running on a Franklin.
Note: This patch should not be applied except by Franklin 1000 and, possibly, some
other clone users. On a //e, //c or IIgs it causes ProDOS to not see an 80-column card
or some extra memory.
The patch is not needed for Franlin 2000 series machines (the ones that emulate a IIe
and IIc) or any of the Laser 128 series. You would not want to apply the patch to
these units because they have emulated 80 column cards and 128k (expandable to 1MB on
Lasers).
To do the patch, procede as described for the main patch and also do this ...
READ Track 0, Sector 0
Search for (Hex bytes): AE B3 FB E0 38
When you find the above, change it to A2 EA EA E0 38
and write the changed sector back to diskette.
_________________________
From: Rubywand
040- What are some good DOS 3.3 and ProDOS references?
DOS Books
The DOS Manual from Apple
Beneath Apple DOS by Worth & Lechner
Apple II User's Guide by Poole, Martin, and Cook
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
_________________________
From: Dennis Jenkins, Rubywand, Dave Althoff
041- How can a BASIC program tell which DOS it's running under?
A pretty good way is to check the three-byte JMP command starting at $03D0. If
it's 4C 00 BE, you're running ProDOS; if it's 4C BF 9D, you're running DOS 3.3 or a
compatible variant (such as Prontodos).
Two (moderately rare) factors may change the DOS 3.3 JMP: 1- On old "slave
disks" created on sub-48k Apple II's, DOS loads in at a lower address; 2- DOS 3.3 is
sometimes moved up into the Language Card. So, your best procedure is probably to
check for ProDOS and, if it isn't ProDOS, just presume that it's DOS 3.3.
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