Reading Floppies | FDC the BBC disc
read/writing program
Information and Download |
Direct Link | Download of Xfer, direct link software
Direct Link Cable Offer BBC to MAC (offsite link) |
Disc Image Types | A brief explanation of some disc image types |
Disc Image Manipulation
|
BBCIM download and information
Download of BBC EXPLORER 2 |
.inf Files | Explanation of .inf files and their use |
Reading DOS discs on a BBC | DOSFS |
These are some of the things it is possible to do:
FDC is a disc reader/writer/formatter that will run in a window. It will not work on all PCs, especially newer ones. If you try everything on this page and it will not work, then I cannot help you! You need a disc drive of the same size on your BBC and PC, either 3.5" or 5.25".
There are many uses for FDC. I use the program to:
The disc is read in as an image that can then be used in a BBC emulator on the PC. The download of FDC here contains full instructions for its use. I have removed the pieces from those instructions that I find useful and placed them below:
FDC Commands:
fd0, fd1, fd2, fd3
Select which floppy drive to use. Default is fd1. Most
systems support only two drives so fd2 and fd3 may not do anything useful.
(CJR: fd0 is drive A. fd1 is drive B)
BBC
Default. Set up all disk parameters for BBC DS SD 40-track 10-sector
floppies on 360K PC drive. For 80 track floppies in a 1.2M drive also enter
CYL 80 (and DDINHD might be needed).
BBC80
Same as bbc but for 80 track disks (you may need to enter DDINHD
after this).
Parameters set are: 'bbc', then cyl80.
BBC640
Sets 3.5" ADFS L 640 K format with a head1alias =1. If it doesn't work,
try head1alias=0.
Parameters set: 'bbc', cyl 80, bytes 256, sectors 16, head1 1 (CJR:
this format works fine on my 5.25" drive too)
(CJR) For ADFS M set the above parameters but use 'read0' as the discs are single sided
(CJR) For ADFS S set the above parameters but also type 'cyl 40' and remember to use only 'read0' as the discs are single sided
DDINDD
Set data rate for double density (e.g. 360KB) disk in a double density
(i.e. 360KB) drive. Note that if you are using a generic 360KB 40-track
drive, you will probably want to set SINGLESTEP too.
DDINHD
Set data rate for double density (e.g. 360KB) disk in a high density
(i.e. 1.2MB) drive. Note that if the disk comes from a machine that
uses normal (e.g. 360KB) 40-track drives, you will probably want to set
DOUBLESTEP too.
FORMAT, FORMAT0, FORMAT1
Format and verify the disk using the currently set parameters.
S[TATUS]
Display all disk settings.
W[RITE] filename, WRITE0 filename, WRITE1 filename
Write entire contents of disk from an (for double sided: interleaved)
image file. All sectors appear in the same order on the disk as in
the file. WRITE0 and WRITE1 write the imagefile to side 0,1
Those are the abbreviated instructions for fdc. If you want the full instructions, please download fdc and extract them.
In Short
For an 80 track double sided DFS disc
Insert your BBC disc into the PC drive
Run FDC
Type fd0 (if you put the disc in drive A)
Type BBC80
Type read <filename>
For ADFS L, fd0, bbc640
For ADFS M, fd0, bbc640 and use 'read0 filename' only
For ADFS S, fd0, bbc640 cyl 40, and use 'read0 filename' only
Simple as that
To write the image back, type the above commands, but instead of 'read'
type 'write'
To read/write single sides of discs, type read0 or read1 (write0 and
write1)
Some settings that you may find useful not documented:
CP\M format (80 track single sided) Bytes 256, Sectors 10, Cyl 80, read0
<filename> This is the default of FDC apart from CYL 80
ADFS 800K discs: Sectors 5, bytes 1024, m1, dd, Cyl 80, head1 1
OR head1 0 ALSO. Maybe minsector 0 needs setting too as I discovered with the
Archimedes discs
FDC and Windows XP
Thanks to Jason Watton for prompting me on this one. My laptop runs Windows
XP and for almost a year I was tearing my hair out trying to read BBC discs
using it. The solution was to create a boot up floppy, place ramdrive.sys on
to it from my Windows 98 CD. Add the line device=ramdrive.sys 32767 /E to the
config.sys file. place fdc and omnidisk on to the floppy and reboot into DOS
with floppy as A and a ram disk as C. Image BBC discs on to C and then copy
them back to HD floppy. Reboot into Windows and copy the images from A.
If you are no good with a soldering iron, I am now offering to make up the
required serial cable for folks. 9 pin at the PC end. There is a chance the
software may not work on your PC. I think this is caused by an incompatible
command used in the software presently available. Please let me know if you
have problems. Ordering details in the 8BS Advert. I can now supply you with
the parts to make these leads up too.
This is taken from the very tatty piece of paper with the drawing that I use when making up the link. Please remember that the numbers on this dawing DO NOT represent any numbers that may appear on the plugs, they are just reference points
There are a number of formats used by people.
For double sided discs, I use interleaved (.dsd and .adl) as it is a more rapid process, the image is read in with one sweep of the heads and the resulting single file is then the finished article. The tracks are stored in the image alternately, track 0 from side 0, then track 0 from side 1, then track 1 from side 0 and so on. This format is known as 'interleaved'. Some folks (especially programmers I think) don't like this as it complicates the software that handles the image. However, the software to handle this format exists, works fine and is available here in FDC and BBCIM.
.dsd and .adl
The fdc commands 'read' and 'write' without the trailing 0 or 1 produce
an interleaved disc image. If you are reading a DFS disc, use the extension
.dsd, if you are reading an ADFS disc, use the extension .adl
.ssd .0 .1 .adf
The fdc commands 'read' and 'write' with the trailing 0 or 1 produce
a single sided image. If you are reading a DFS disc, use the extension
.ssd or .0 or .1. Logically, if you are reading in a double sided disc,
you are better off using the .0 and .1 extensions to denote which file
is which side of the disc. If you are reading in an ADFS disc, you should
use the file extension .adf
If you use the above file extensions, then most BBC Emulators on the PC will
be able to directly read the image.
.img
This is another form of disc image used. It is the same as the above
.ssd format. I do not use this extension.
What format are the 8BS pool images in?
The 8BS CDs available contain disc images available in all formats.
For example, a .dsd image will have its counterparts of .0 and .1. An .adl
image will have its counterpart of .adf. So no-one can complain.... Can
they?
A couple of quick hints for BBCIM
To turn an ADFS interleaved image into a non-interleaved image (makes
a copy of the image first, then alters the original ):
bbcim ds2ss <filename>
To turn an interleaved DFS disc image into two single sided images:
bbcim splitds dd <filename>
This program is probably the easiest way to handle the software you can pick up from all over the internet that has accompanying .inf files.
Well worth a look at.
Basically, what you see here is a BBC disc that has been split up into separate files. The actual BBC file is the program without an extension. The file with the same name and a .inf extension contains the BBC filename, load, save and run addresses and also directory and read write access information. This information cannot be stored by the PC in any other way.
Before you can use these files on an emulator, you will need to turn them into a disc image. That is where Lawrie Whiffen's BBC Explorer 2 comes in. You can simply drag the files into a disc image. Once the files have been put into a disc image, you can then use FDC to write the image to a BBC floppy.
You can also write these files to a BBC disc on a BBC using a direct link and the software XFER or PCXFER.
It is possible to read a 720K DOS disc on a BBC or Master using a 1770 (or 177x) disc interface. It is not possible to read DOS discs using an 8271 controller.
DOSFS available on 8BS-51 loads into sideways RAM on the BBC or Master and
acts as another filing system. Simply refer to it with *DOS. This is ideal for
transferring individual files between PC and BBC. Usually only text files of
course. It does have a couple of problems with display of files on the disc
(sometimes deleted files show up!Win95FS long filenames extended entries show
up in their raw state. DOSFS doesn't take any notice of the "Label" attribute,
which is part of the method used to hide the extended entries), but in general
I find it quite useful.