Regardless of the platform, there is a common need to back up the customers' job onto tape. Those using the SparcStation, have a cartridge icon that sends the data out to a 150-Meg Cartridge. Those using the 50000S, have a magtape drive (they usually weigh a ton) that is used for archiving jobs.
No matter how large or small the job, it still needs to be archived. Tapes can get quite expensive, with cartridges running from $15.00 to $20.00, and magtapes costing $10.00 to $15.00 each.
It would be nice if there were a way to utilize regular floppy diskettes for backup of jobs. Yes, they store only a fraction of what the other media does, but they are more readily available and cost much less.
Well, it turns out that if you are willing to use the unix shell, you can use floppies... on both the Sun SparcStation and the Cadnetix 50000S.
The Sun SparcStation is perhaps the easiest to implement diskette storage. (The Cadnetix manuals mention mounting a floppy direct from the worksurface, but I have not yet been able to do it.)
To be able to use floppies on the Sun, you will need to be able to log in as root (or su). Then, 'cd' to /etc.
In the etc directory, there is a file called 'fstab'. Unix is cryptic... but I think this is an acronym for 'f'ile 's'ystem 'tab'le. In this file are a list of all of the valid file systems that unix is able to mount.
Use 'more' to display this file to the screen. In this file, if you do not see a line with 'pcfs' in the line (the MS-DOS file system), then you will have to add it. Even if it is there, you should check it to make sure that it is similar in appearance to what is supposed to be there.
/dev/fd0 /pcfs pcfs rw,noauto 0 0
Once you have edited the fstab file, you are almost ready to mount a floppy.
First, you will need to create a couple of unix csh files. Cd to your home directory and create a file by the name of 'fmount'. In this file put the following exactly as it appears below.
#!/bin/csh -bmount /pcfs
This file mounts the floppy diskette for reading and writing.
Next create a second file for unmounting the floppy. Name it 'feject'.
#!/bin/csh -b
umount /pcfs
eject
This file will not only unmount the floppy, but it will also eject the floppy from the drive.
(Note: In the above examples, be sure to put the blank line and any spaces in your files as unix is a
very persnickity language and needs to see things a specific way for commands to work.)
Let's see if we can read an MS-DOS diskette.
To do so, insert a floppy into the drive.
Make sure that the diskette is not write-protected.
Also, be sure that there are files already on the diskette, for this exercise.
Next, type...
fmount
If you receive error messages at this point, verify that you are using an MS-DOS diskette with files on it, and that the diskette is not write-protected. If this is not the problem, try to type the following...
mount /pcfs
If you still cannot get the floppy /pcfs file system to mount, back track carefully thru the above procedures. You might even try a
login fastboot
If the file system mounted correctly, you should be able to type...
ls -l /pcfs
and see a list of the files currently on the floppy. To copy files to the floppy, type...
cp [filename] /pcfs
...the same way that you normally use the unix commands.
One drawback to using MS-DOS formatted floppies, is their MS-DOS filename limitations. You know, the 8.3 character limitation. Copying files from unix (which many times have filenames up to 30 characters, over to MS-DOS, means that you may have to create a shorter name to fit within this 8.3 limitation.
Type feject to unmount the floppy and eject it from the drive. If all is well, the floppy will be ejected. If the computer does not recognize the feject command, you might have to resort to inserting a paper clip into the magic hole and ejecting the floppy manually. Before doing so, you may try to manually type the commands to unmount the floppy drive, followed by the eject command.
To format MS-DOS floppies on the Sun, type the following...
fdformat -dl
-d = puts MS-DOS filesystem and boot sector on the diskette
-l = formats in low density (leave this off for high-density)
(WARNING!! This command will erase any any information previously stored on the floppy!)
After you are able to mount and unmount floppies, you may realize that it is far easier to copy Gerber (or other) files directly from the workstation to floppy. It is also possible to use this method for importing Netlists and other information into the Sun environment.
Taking it one step further, there is a unix version of lharc that allows one to compress files and copy them over to floppy. One could use this method for compressing Gerber files, then copying them to floppy to be sent to the photoplot vendor. (Lharc is compatible between unix, MS-DOS and Amiga filesystems, allowing for one to lharc on one system and un-lharcing the files on another system).
Finally, diskettes provide a cheap alternative to the cartridge tape drive (for smaller jobs). One is able to use readily available unix commands to put all of the files into a compressed format (complete with subdirectory structure) that can be copied over to floppy instead of cartridge tape. Maybe not as easy as the Cadnetix Icon Worksurface way of archiving, but considering the costs of tapes, sometimes it is worth the trouble. To do so (verify the following commands in your unix manual), type...
tar -cvf - [subdirectory filename] >[newname].tar
This should 'c'reate, 'v'erbose, from a 'f'ile, and put the resulting tarred file into the file with the tar extension. Tar does not compress this file at all, and the resulting file size will be as big or bigger than the original files. To extract your file from the tar format, type...
tar -xvf [filename.tar]
(Note: Cadnetix uses a version of tar to save your files out to tape. As a result, your archives will occupy as much space on tape as they do on your hard drive... if not more.)
To compress the files into a smaller size, type the following...
compress [infilename]
(To learn more about compress, and compression options you can use 'man' or look up the compress command in a unix manual.)
Compress, will create a file that is compressed to a smaller file size, allowing it to fit on the floppy. This file will have a .Z extension tacked onto the end of the file name which means that the file is compressed.
To uncompress a compressed file, type...
compress -d [filename].Z
(Note: the .Z is an uppercase 'z' that compress appends to the end of the inputfilename, and expects to see when it uncompresses the file, or else it will abort.)
I mentioned at the beginning of this article that there were ways to utilize some of this information for transferring files from/to the proprietary 50000S workstation. Well, I see that I've run out of time, but it is possible. Perhaps this will be a topic for a future article.
Conclusion: This article contains information that may or may not be useful to the average designer. It has been provided, mainly as a starting point for future designers' articles. These articles should include software tips, bug workarounds, etc.
It is recommended that designers that use other systems (as well as Cadnetix designers) look at some of the help that they can give to each other via web sites such as this.
The bottom line... we, as designers, are all in this together. If we help each other out, then we all benefit.