RamFAST SCSI and the Floptical drive
By Chris Nelligan
Copyright (c) 1993 Apple Users' Group, Sydney
Republished from Applecations, a publication of the Apple Users' Group, Sydney, Australia.
A new disk technology is now available, it is the Floptical disk. This new disk with a maximum storage capacity of 21 megabytes is still packaged as a standard 3.5" disk. To use these new disks, a new disk drive is required. The disk format and the new drive were designed by the company Insite peripherals. The technology has been licensed to different manufacturers, for example PLI and Applied Engineering.
The drive also has support for regular double sided and double sided High density 3.5" disks. It is possible to read, write and format disks in 720k and 1.44 meg formats. My main use of the drive is for the 21meg floppy disk, it is perfect for backups, and archiving.
The drive is a SCSI device and therefore does not plug into the back of your regular Appledisk 3.5 drive, it requires a SCSI card. Available SCSI cards for the Apple II computer are made by Apple Computer (the Apple II High Speed SCSI card) and by CV Technologies (the RamFAST).
To use the new SCSI Floptical drive under GSOS on your IIGS a device driver is required. If you are using an Apple High Speed SCSI card you will need Richard Bennett's driver or another similiar. The RamFAST has built in support for the drive (ROM version 3.0k or greater is required).
The RamFAST SCSI card is a cache card. This means that as GSOS writes to a SCSI drive the data goes into a buffer on the RamFAST card (similar to a printer spooler). When this buffer becomes full or no more data is written into the buffer after a nominal time, the card then transfers the data to the disk device in the background as you continue to use your computer.
When reading, the RamFAST reads extra blocks from the disk drive hoping to anticipate what the next block of information GSOS will want. Eg. GSOS asks for 5 blocks from a file, the RamFAST may read 25, then when GSOS asks for the next 5 blocks, the RamFAST simply passes it out of its cache.
The RamFAST comes with two cache sizes - 256k and 1 megabyte.
The RamFAST lends itself very well to the floptical drive. Since the drive is slow, the RamFAST captures all of the data in the cache and then writes it to the drive in the background as you start to do another copy or run your next application.
Under ProDOS, the floptical disk formats to a maximum capacity of 19.5 megabytes. The time to format a floptical disk is about 20 minutes, this time does not very on the SCSI card you use.
To highlight the speed of the RamFAST SCSI here are some disk timings. All disk reads and writes are to a formatted ProDOS 19.5 meg floptical on a Rom 3 IIGS running at 2.8mhz.
Finder copy AppleWorks GS folder (1,343k) to floptical - 35 seconds
Finder copy AppleWorks GS folder (1,343k) to my Hard disk - 23 seconds
Finder run AppleWorks GS from floptical - 25 seconds
Finder run AppleWorks GS from Quantum Hard disk - 22 seconds
Finder trash AppleWorks GS folder from floptical - 3 seconds
Finder trash AppleWorks GS folder from my Hard disk - 3 seconds
Finder copy System folder (6,734k) to floptical - 6 minutes and 25 seconds
Finder copy System folder (6,734k) to my Hard disk - 7 minutes and 30 seconds
Finder trash System folder from floptical - 1 minute 25 seconds
Finder trash System folder from my Hard disk - 2 minutes and 8 seconds
ProSEL disk timing statistics on the floptical drive are :
Linear read efficiency test = 5.08 milliseconds
Random read efficiency test = 48.30 milliseconds
Mean access time for OS overhead = 1.05 milliseconds
The floptical drives are available in Australia, I suggest that you shop around at some of the peripheral computer dealers.
The RamFAST SCSI card is available from Two Series Software (02 606 9343). With the aid of the RamFAST the floptical drive is a dream to use.
The best thing about the floptical is that the 21 megabyte disks are $35 each in a pack of 5 and the price is continuing to drop. Try the companies Direct Access and PCS Australia for the disks. The cost per megabyte is very cheap compared to a hard disk or a removable. Insite Peripherals intend to produce 40 and 80 megabyte 3.5" floptical disks shortly as well!

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