Creating BIOMAP CDROMs - Instructions & Procedures
The procedure for creating CDROMs for the BIOMAP acoustic data is straightforward, involving transfering the data from the source (diskettes, hard disk or Bernoulli drive) to the CDROM writer's PC remote hard disk, creating a logical then physical image of the data to be transfered on the local hard disk, and finally copying the physical image to one for more CDROMs. The instructions below describe these steps in detail.
Transfer Data to CDROM PC
In the example used here, the original 120 kHz and 420 kHz acoustic and ESS (environmental ship sensor) data are stored on a standalone PC on its hard drive, running DOS. In order to make these data available to the CDROM PC, the data were first transfered, via the network, to a Sun workstation. This process took about two hours. The data files were copied into separate directories on the Sun to a drive know as "g:" to the PC as follows:
- / - top level directory contains the copyright and readme.txt files. The readme.txt contains information specific to this data set.
- /bio_120 - 120 kHz acoustics data
- /bio_420 - 420 kHz acoustics data
- /al9508/ess - environmental ship sensor data for ALBATROSS IV cruise 9508
Software Preparations
The DOS-based CDROM transfer software is located in the \gear directory. With a standard editor, edit the gear.ini file to reflect the current date, the CDROM title, customer name (i.e. WHOI), and confirm that the CDROM will use the [ISO 9660] standard.
For the MSGEN (Multi Session Generation Program) to work,
- the GEAR.MSG file must be in the destination subdirectory,
- the \gear (i.e. software) directory must be in the PATH statement, and
- the program must be able to find the .ini and .msg files. This was accomplished by copying these files to the working (data) directory although there may be a way to use an environment variable to accomplish this.
Program Operation
To start the program, enter \gear\msgen. The program prompt is CD>. Although it is possible to generate the CDROM directly during the construction of the logical file, the procedure described here first creates the logical image, then the physical image. The physical file is then copied to the CDROM.
Create New Volume
Enter the command newvol biomap 74 where biomap is the name of the CDROM volume and 74 refers to the size or length of the CDROM, in this case, 74 minutes. The program responds confirming the creation of this volume and says that Track 1 is created.
Copy Data to Logical Image
During the creation of the logical image, the program confirms the existence of all specified files, checks the file sizes, and effectively creates a directory structure for the files that will go onto the CDROM. This step only takes a few minutes since the data are not read at this time, only the file attributes are checked.
There are several ways to copy the data to the logical image, this procedure only shows one of the ways. For more information consult the program documentation.
First, create the directories in the logical image as follows:
- newdir bio_120
- newdir al9508
Next,"copy" the data files using the copytree command to the correct subdirectory as follows:
- cd bio_120
- copytree g:\bio_120 where g:\bio_120 is the source of the data files, in our case located across the network on a Sun workstation.
- cd ..\al9508
- copytree g:\al9508 where g:\al9508 contains the ess subdirectory and ..\ess contains the ess data.
- cd ..
- copy g:\readme.txt
- copy g:\copyright
Create Physical Image
To create the physical image or volume (note: this file is stored on CDROM PC's hard disk; it is not output to the CDROM yet) issue the command
physvol. This step took about an hour for approximately 400 Mbytes of data, accessed over the network.
Setup Command
The SETUP command establishes certain perameters of the output to CDROM operation such as
- whether output is direct from a physical or logical image. In this case, it is from a physical image so answer Y
- enable record: Y
- recording speed [1, 2 or 4 x]: 4 {if you were writing direct from a logical image you might need to slow down the writing operation in which case you would enter 1 or 2}
- fixation: Y {Once "fixated" the CDROM cannot be appended to}
- multisession: N {enable mulitsession if you will be writing more than one image to the CDROM}
- save setup: Y
Writing CDROM
To actually place the physical image onto the CDROM issue the write biomap command, where biomap is the name of the volume. This step takes about 15 minutes for 400 megabytes writing at 4x speed. Note that the CDROM must be placed in a jacket in this writing unit. To create a second copy of the CDROM, remove the first CDROM and reissue the command.
Creating subsequent CDROMs
In this case, a second CDROM was needed to store the 420 kHz data. The procedure is similar to the above as follows:
- delvol biomap, delete the biomap volume in preparation for creating the next CDROM. The logical and physical images are deleted.
- newvol biomap 74
- newdir bio_420
- newdir al9508
- cd \
- copy g:\copywrite [should be g:\copyright]
- copy g:\readme.txt
- cd bio_420
- copytree g:\bio_420
- cd ..
- cd al9508
- copytree g:\al9508
- physvol
- write biomap
- write biomap, to make second copy of CDROM