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- MSODBALL v2.00 J. Elliott, 14 December 1993.
- ================================================================================
-
- In this documentation, the acronym DOS means the PC operating systems MSDOS,
- PCDOS and DRDOS.
-
- If you have used MSODBALL or MSODBALA v1.00, please read the section entitled
- "update information".
-
-
- Introduction
- ▓▓▓▓▓▓▓▓▓▓▓▓
-
- MSODBALL is a format-conversion utility for use on an Amstrad CP/M computer
- which has a 3.5" 720k disc drive (A: or B:).
-
- It can convert a standard CP/M (or LocoScript) 720k disc to a non-standard
- DOS format. Conversely, it can convert a DOS disc in this non-standard format
- to CP/M 720k format.
-
- Format-conversion usually is much quicker than copying files between CP/M and
- standard DOS-format discs. Also, only one disc is needed. However there is a
- risk that specialised programs (see below for a list of known examples) may not
- be able to use the non-standard DOS format.
-
- It is emphasised that MSODBALL merely enables files on a disc to be accessed
- by either the CP/M or the DOS operating systems. There is no guarantee that the
- files accessed will be of use under both systems. Usually only ASCII files are
- usable directly, although some CP/M machine-code programs may be executed under
- DOS by way of public domain or shareware emulation programs. If you save BASIC
- programs as ASCII files, they can be adapted for DOS-type BASIC (Locomotive
- made a version of Mallard BASIC for the PC - I don't know whether it is still
- available).
-
- MSODBALL runs under CP/M. Type:
-
- MSODBALL <RETURN>
-
- to start.
-
- Screen Messages
- ▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓
- If you have two disc drives, you will see the message
-
- "Two drives detected - use A: or B: ?"
-
- appear. Only drives A: and B: can be used. Users of GEM or InSyder hard discs
- should type A: or B: and the program will use the appropriate floppy drive C: or
- D:.
- When you select a drive it will then be used for the entire duration of the
- program. To change to the other drive, leave the program and run it again.
-
- The main message sequence can be represented pictorially as:
-
- +--------------------------------------------------+
- | E (xamine disc in drive A:) or Q (uit to CP/M) ? |
- +---------------------------------------+----------+
- |
- +-----------------------------------+-------------------------------+
- | | |
- +---+-------------------------+ +-----+------------+ +--------------+---+
- | Disc cannot be converted - | | CP/M 720k format | | DOS oddball |
- | Not a suitable disc format. | | detected. | | format detected. |
- +-----------------------------+ +-----+------------+ +--------------+---+
- | |
- +----------------------------+------+---------+ |
- | | | |
- +---+-------------------------+ | +-------------+---------------+ |
- | Disc cannot be converted - | | | Disc cannot be converted - | |
- | Not enough free space. | | | Too many user 0 files. | |
- +-----------------------------+ | +-----------------------------+ |
- | |
- +--------------------------------+--------------+ |
- | C (onvert to DOS oddball format) or Q (uit) ? | |
- +-----------------------------------------------+ |
- |
- +----------------------------+----------------+---------------------+
- | | |
- +---+-------------------------+ | +-------------+-----------------------+
- | Disc cannot be converted - | | | Disc cannot be converted - |
- | Too many directory entries. | | | unsuitable sub-directory structure. |
- +-----------------------------+ | +-------------------------------------+
- |
- +--------------------------------+------------+
- | C (onvert to CP/M 720k format) or Q (uit) ? |
- +---------------------------------------------+
-
- Some other messages you may see are:
-
- "No files found"
-
- - The disc is empty (DOS discs only).
-
- "No files in User 0."
-
- - There are no files in User Area 0. There may or may not be files in other
- user areas (CP/M discs only).
-
- "Disc cannot be converted - The directory is corrupted."
-
- - The directory is claiming that the disc contains more than 706k of files.
- Since this is not possible, the program decides that the directory is not
- trustworthy. If any one file is supposedly bigger than 706k, its name is
- printed for diagnostic purposes.
-
- "Convert file date-stamps (Y/N) ?"
-
- - DOS files all have a date-stamp, which says when the file was last updated.
- In CP/M, this is optional, so when the disc is being converted from DOS to
- CP/M format you may be asked whether you want to use this option. LocoScript 1
- and AMSDOS cannot use discs with date-stamps.
-
- "<something> is password protected. Type password or press ENTER to abandon"
-
- - See the section on "Password conversion" below.
-
- Notes on Screen Messages
- ▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓
-
- The CP/M user 0 directory (or the DOS root directory) will be displayed if
- the disc examined is suitable for conversion, looking similar to a listing
- produced by DIR (in DOS, DIR /W). Any underlined filenames are DOS sub-
- directories. In addition, in the CP/M to DOS direction, a display of file
- allocation by user is shown, similar to that produced by SHOW [USERS].
-
- Insufficient disc- or directory-space messages are likely to occur only if a
- disc is almost full in its original format. Respective capacities are:-
-
- CP/M 720k format: Max directory entries = 256, File space = 706K.
- DOS oddball format: Max root directory entries = 240, File and sub-directory
- space = 706K.
-
- The figures on disc usage for a disc in DOS oddball format do not include
- sub-directories, so there may be more free space shown by MSODBALL than by
- DOS programs like DIR.
-
- CP/M User-Numbers and DOS Sub-Directories
- ▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓
-
- CP/M user areas (or Locoscript groups) and DOS sub-directories both allow
- multiple files with the same name to exist on a disc.
-
- MSODBALL supports CP/M user areas and sub-directories of the DOS root
- directory. It attempts to avoid filename ambiguity by equating user areas and
- sub-directories in the following way:-
-
- CP/M to DOS conversion: Files found in CP/M User Area 0 are placed in the
- DOS root directory. Files found in user areas 1 to 15 are placed in sub-
- directories with names USER#01 to USER#15 (but see "Empty files" below).
-
- DOS to CP/M conversion: Files found in the root directory are placed in CP/M
- User Area 0. Files found in up to 15 sub-directories of the root directory are
- placed in user areas 1 to 15, with each sub-directory name preserved as the
- name of an empty file in the relevant user area.
-
- After a disc has been converted to CP/M format, type DIR [USER=ALL] or
- SHOW [USERS] to see what files have been placed where.
-
- Since LocoScript uses user areas 8 to 15 as storage for "limbo" files, it is
- inadvisable to use discs which have files in these user areas under LocoScript.
- This also means that after a disc has been converted to and from DOS format,
- limbo files will not necessarily be in the same groups that they were in
- before, and some may have been "recovered" and inhabit formerly empty groups.
-
-
- File attributes and datestamps
- ▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓
-
- When files are being converted, their attributes (eg read-only, archive)
- are converted with them. Here is the full list of how they are converted:
-
- CP/M to DOS:
-
- Read-Only -> Read-Only
- Archive -> Archive
- System -> Hidden.
- The attributes F1-F4 are not converted.
-
- DOS to CP/M:
-
- Read-Only -> Read-Only
- Archive -> Archive
- Hidden -> System
- System -> F4.
-
- Datestamps are converted in the CP/M to DOS direction, and optionally in the
- DOS to CP/M direction. The option will not be offered if there is not enough
- room in the directory for the extra information.
- The CP/M "update date" is taken as being interchangeable with the DOS file
- date. If there is no date entry for a file, the date will be set to be the
- current date as given by the computer's clock. When converting from DOS to CP/M
- format, the "update" and "access" datestamps are used; the "access date" is set
- to be the current date.
- Disc labels are transferred correctly in both directions.
-
- Password conversion:
- ▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓
- In CP/M and DRDOS (but not MSDOS or PCDOS) files can have a password.
- When a disc is converted, CP/M passwords are changed to DRDOS passwords, and
- vice versa. Discs with DRDOS passwords can be used normally under MSDOS or
- PCDOS, but the passwords will be ignored.
- Password conversion between the formats works as follows:
-
- CP/M to DRDOS:
-
- If a disc has a password, MSODBALL will need this password to be typed before
- conversion can proceed. The disc password will become the volume label password.
- File passwords are automatically converted.
- If password protection is not enabled for a disc (eg SET [PROTECT=OFF] has
- been used), all passwords will be removed during conversion.
-
- DRDOS to CP/M:
-
- Because of the way DRDOS passwords are stored, it is impossible to convert
- them automatically into CP/M passwords. Therefore, during conversion, you will
- have to type the password of every password-protected file. MSODBALL will try
- to minimize this typing. For example, if all the files on the disc have the
- same password, then you will only have to type the password once.
- Directory passwords are not converted.
-
- Limitations and empty files:
- ▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓
- On a disc converted to DOS format, file sizes are multiples of 128 bytes.
-
- MSODBALL cannot convert DOS oddball-format discs which have more than 15
- sub-directories or which have sub-directories of sub-directories.
-
- Empty files are treated as follows:
-
- Empty files in User 0 are not transferred.
- The last empty file in each User 1-15 becomes the name of the corresponding
- sub-directory. So, if a LocoScript disc had a group called LETTERS, this would
- be converted to the sub-directory LETTERS.GRP. If the group had not been named,
- the sub-directory would have preserved its USER#nn name. On being converted
- back, the sub-directory LETTERS.GRP would become the LocoScript group LETTERS.
- Since sub-directory names cannot be duplicated, you will find that if there
- are two or more user areas with the same "name" (for example, if there is an
- empty file called CONT in user areas 1, 2 and 3), then the sub-directory names
- will be slightly different (in the above example, you would have the sub-
- directories CONT, CONT.0, CONT.1 respectively).
-
- Some programs incompatible with DOS Oddball Format:
- ▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓
-
- This is by no means a complete list. It merely details the programs that I
- have tested and found wanting.
-
- Under CP/M:
-
- * MSDISC and MSDISCA cannot use DOS oddball discs.
-
- Under DOS:
-
- * The Norton Disc Doctor does not recognise DOS oddball discs, and attempts to
- "repair" them. The process is fatal for the disc concerned.
-
- Others:
-
- * The Apple File Exchange program on the Apple Macintosh does not recognise DOS
- oddball discs. This means that MSODBALL cannot be used to transfer data
- directly to Macs.
-
-
- Update information for v1.00 users:
- ▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓
-
- This program replaces both MSODBALL and MSODBALA v1.00. Some of the messages
- have changed slightly, and there are a few other changes:
-
- 1. If you have two disc drives, you can choose which one to use at the
- beginning of the program.
- 2. The cursor is a reversed-video *, not a ?.
- 3. You are offered the option to convert date-stamps from DOS to CP/M
- format. If you intend to use the disc under LocoScript 1 or AMSDOS, answer No;
- otherwise it depends on whether you prefer to use time-stamped discs under
- CP/M.
- 4. File sizes are not shown in the directory listing. Sub-directories are
- shown underlined rather than followed by <DIR>.
-
- Technical differences are described later.
-
- Error codes
- ▓▓▓▓▓▓▓▓▓▓▓
- If the program ends with the report "CP/M Error On x:" then the "Extended
- BIOS Function" that it mentions is:
-
- 0086: Error in reading from the disc.
- 0089: Error in writing to the disc.
-
-
- Physical-Sector Usage
- ▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓
-
- CP/M 720k: 1 (disc spec) + 8 (unused) + 16 (directory of 256 entries)
- + 1412 (files) + 3 (unused) = 1440 sectors = 720K.
-
- DOS oddball: 4 (boot) + 6 (2 FATs) + 15 (root directory of 240 entries)
- + 1412 (files + sub-dirs) + 3 (unused) = 1440 sectors = 720K.
-
-
- Changes from v1.00
- ▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓
-
- Version 2.00 was written from scratch. The only code in common with v1.00
- is the DOS Oddball boot sector.
-
- 1. MSODBALL v2.00 (8k) replaces MSODBALL v1.00 and MSODBALA v1.00 (18k each).
- This results in a 28k saving of disc space.
- 2. Date-stamps and disc labels are converted. MSODBALL/MSODBALA v1.00 corrupted
- the directories of discs with date-stamps or disc labels, by treating the
- date-stamps/labels as real files.
- 3. Empty files become sub-directory names, so LocoScript group-names are
- preserved.
- 4. The unhelpful message "Disc-related error" has been replaced by a set of
- messages explaining what the error is.
- 5. CP/M and DRDOS passwords are supported.
- 6. The program will run on any Amstrad CP/M computer (ie PCW/CPC/Spectrum +3).
- 7. Discs with corrupted directories are more likely to be detected.
-
- Once a disc has been converted to CP/M format by MSODBALL v2.00, it is no
- longer recognised as a CP/M disc by MSODBALL/MSODBALA v1.00. I do not know
- why.
-
- Use of CP/M sector editors
- ▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓
-
- The CP/M sector editor DU87 can be made to read DOS oddball format discs, if
- used in conjunction with the DU51 formatter. To use, type:
-
- DU51 <RETURN>
-
- Use option 1 (select disc type), then the drive you are editing your disc in.
- Then choose "Fixed format"; then format F - "MSDOS Oddball". Leave DU51.
-
- Now run DU87 and insert the DOS oddball disc. DU87DATA.DOC describes the
- arrangement of such a disc.
-
- When you have finished, use DU51 to change the drive you were using back to
- "Auto Select".
- ________________________________________________________________________________
-
- The DOS Oddball format and boot sector were invented by G R Mortreuil.
- ________________________________________________________________________________
-
- MSODBALL (c) 1993 J C Elliott. Parts (c) 1991 G R Mortreuil. This program is
- released to the public domain on condition that it is not sold for profit and
- is not distributed without this documentation.
- ________________________________________________________________________________