Read OS-9 Disk
Read floppy disks written under a OS-9 level 1 environment on PC-based hardware.
See also a more detailled description "[Reading OS9 Disks in Linux]".
See also [general hints on how to read old floppy disks].
Disk were written on a developement system for embedded application system consisting of
- 19" rack based system (Eurocard GESPACs GESBUS bus system G-64)
- Harddisk drive ST-251 (20 MByte)
- Floppy disk drive 5.25"
- Floppy disk controller based on FDC chip WD 1791
- capable of single (FM) and double (MFM) density format
- Telex Adapter (self developement)
- EPROM/RAM-Disk, backup battery buffered (self developement)
- Pentium II 233MHz AGP/PCI/ISA mainboard
- Adaptec AHA-1542CF or AHA-1542B
ISA-card, only floppy controller is used, Linux recognises it as "post-1991 82077")
This controller card is essential to read FM (single density) formats!
Note: Its FDC is not able to handle 128 byte sector double density formats!
- 5 1/4" floppy disk drive (NEC, Epson or similar)
... to start a CDROM-based Linux distribution like Knoppix 3.4 - systems of this kind may not boot from SCSI-CDROM or even USB stick.
NOTE: You may use any other Linux distribution as long as they support or provide the fdutils package (e.g. Ubuntu 10.04 LTS) and the controller hardware is supported!
Check other Floppy Disk Controller for PC hardware (if you want to read FM or single density formats):
- Onboard floppy controller: disabled
- Floppy controller:
Sometimes an add-on floppy card will have a 765-compatible floppy controller that supports FM (single density). The Adaptec AHA-1542CF or AHA-1542B SCSI hard disk controller includes a floppy disk controller on the same card which supports FM and works with both 300 RPM and 360 RPM drives; as some other Adaptec cards do. This card is easy to use; you just plug it into any spare ISA slot and disable your motherboard FDC.
- Card setup AHA-1542CF (switches):
- 1: off (open) Termination Software controlled
- 2-4: off-off-offIO Adresse 330h
- 5: off Floppy enable
- 6-8: on-on-off BIOS Adress D0000h
- Ctrl-A (SCSISelect) card BIOS settings:
- BIOS Information:
- Revision: 2.02
- Base Address: D0000h
- Firmware Information:
- Revision: B.0
- Checksum: A223h
- !Host Adapter Interrupt Channel: 10
- !Host Adapter DMA Channel: 7
- Host Adapter SCSI ID: 7
- Advanced Configuration Options
- Floppy Controller I/O Port 3F0-3F7
- INT 19h Support: ENABLE
- everthing else: ENABLE
- Support Removeable Disks Under BIOS as Fixed Disks: D
booting and OS support
Booting with a Linux live CD:
- Knoppix 3.4 (Kernel 2.4)
- Boot prompt:
This is needed if the boot procedure seems to hang because the aha1542.o module probing takes really a lot of time ...
- [fdutils] (included on Knoppix distros)
- fdrawcmd (directly read sectors and tracks)
- floppycontrol (initialize/reset the controller)
- [Enhanced os9disk software] from JohannKlasek [download]
(supports FM tracks, bugfixes - see changes below)
- based on [Original os9disk software] from Bob van der Poel [download]
- Changes against original version (dated from 2006):
- Fixed: (os9disk) Memory leaks, handling deleted objects, dateformat, host file changetime
- Added: (os9read, os9guess) Support for single density tracks (additional tool tr0 to read these tracks)
- Added: (sector0) Tool for analysing sector 0 (LSN0) in detail
- Changed: (Readme) some details about PC hardware, updates regarding above changes
Other tools to read RBF filesystem images:
Try to guess the format of the first track (for drive 1, without search for sync identification):
./os9guess -c -1
Copy the whole disk into a image with ...
... giving following dialog:
Read OS9 Disk Read Utility
By Bob van der Poel
And Johann Klasek
Select the disk format/drive combination
0. COCO OS9 40/18 DS
1. MM1 80/36 DS
2. MM1 80/33 DS
3. Univeral 80/16 DS
4. Coco 35/18 Doublestep
5. Coco 80/18 Doublestep
6. DD 80/16, DS, Track0/Side0? FM (single density)
Enter format: 6
Floppy drive (0,1,2,3): 1
Prepare the floppy in /dev/fd1 and enter the name of an
image file. If the file exists it will be overwritten: d1
The images is now stored in file d1.
Analyse an image or a partial image ...
# read sector 0 of an imagefile and show the parameters ...
BTW: sector0 provides more details than os9id from the [os9tools package] (like mtools but for RBF formated filesystems).
Get the files out of the image ...
# show directory recursively (short style)
# show directory recursively (long style)
./os9disk -l d1
# extract all files into directory d1_files/ ...
./os9disk -x -d d1_files d1