BDOS replacements for CP/M 2 and 3
There are a number of public domain replacements for the CP/M BDOS. Here
are their feature lists, extracted from their own documentation:
For CP/M 2
There are three versions of Z80DOS available:
- Version 1.0
- All the features of P2DOS;
- New calls to get and set time stamps.
- Version 2.3 adds:
- Fast directory search system;
- Can be assembled as a ZRL file for the Z-System;
- Call to detect presence of Z80DOS.
- Version 2.4 adds:
- Fast disc reset capability has been;
- Z80DOS can now be assembled with Z80MR;
- All the internal data bases have been moved for compatibility with other
Not to be confused with Digital Research's DOS Plus (a PC operating system,
based on CP/M-86, which emulates PCDOS).
- Will process files of up to 262,143 records;
- Allows for time-stamping of all files (not CP/M 3 compatible);
- Has CP/M 3 compatible direct console I/O;
- Always pauses when ^S is typed;
- Can be interrupted at any BDOS call (if so configured);
- Errors show the calling function, and the file name;
- Implements the CPM3 calls 104 and 105 (set/get time);
- Setuser call (32 = 020h) echoes the user # set;
- Implements a search path;
- Makes all System files, on user area 0, visible to all users for read;
- Maintains the Archive attribute;
- Supports exact file lengths;
- Scans user area 0 for any file names beginning with '$';
- "Compatibility" mode for CP/M 2 programs.
- Changing discs without Control-C;
- Public files;
- Enhanced error messages;
- File date and time stamping (probably not CP/M 3 compatible);
- Free interchange of double and single-sided discs;
- Two kinds of Public files are supported;
- A search path is available which will access system and public files in
directories other than the default;
- The archive file attribute bit is supported;
- Console Status may be checked after every 256 characters of output;
- Time and date stamping of files is supported;
- Two different methods are provided for sensing the change between single
and double sided floppy discs on computers which support both formats;
- Automatic logon of changed discs is supported;
- Permanent media (hard and RAM discs) are supported by a permanent media
vector and a fast disc reset option;
- An internal flags byte is available;
- Error messages have been greatly improved;
- The delete key works like a backspace under function 10;
- Functions may be assembled into NovaDOS to support software designed to
run under ZRDOS;
- Support for high bit character I/O may be enabled in the assembly;
- Disk size can be as large as 65536 * 16K = 1 G byte;
- File size can be as large as 32 * 64 * 16K = 32 M byte.
- Available under the GNU GPL.
- "Direct" console I/O can be mixed with the normal sort.
- Fast disc reset for hard drives.
- Can detect disk changes automatically.
- DMA address can be returned.
- BDOS error mode can be turned on/off.
- Improved error messages.
- 1G max disk size, 32Mb max file size.
- Optional public directories / public files.
- Timestamps are supported by a loadable module, so either the CP/M 3 style
or the DateStamper style can be used.
For CP/M 3
- An obscure bug in the Read Random Record routine has been fixed;
- The user number in the SCB is protected against tampering;
- The clumsy "Trap" system for I/O redirection has been made obsolete;
- Drives set by software to Read-Only stay that way until specifically set to Read-Write;
- Filenames with user numbers are parsed correctly;
- Z80DOS compatible datestamp calls;
- Wheel protection of files (with ZCCP);
- Expanded error messages;
- Command history buffer and improved line editor;
- Bug fix in the CP/M boot loader.
The FreeDOS project is an attempt to write a free replacement for MSDOS.
Try here for more information.
See www.drdos.com for DR-DOS; this
is still a commercial product.
Return to archive listing