My article on the Oliger 2068 Floppy Disc Interface in the March/April 86 issue, had an error that should be corrected. The next to last paragraph incorrectly stated the number of K bytes that an Amdek 3″ disk will store. John Oliger set me straight on this.
The number of bytes the system will store per side (single side, double density) is 195.5K. As mentioned in my review, a side will store 4 regular files plus 1 special file, 0. Correctly, a single file is always 48.5 kbytes, and the special file is about 1.5 kbytes. This comes about by the manner in which the system operates and not by limits in the disc system.
John Oliger also has provided an explanation of “tracks” as used in a disc system. A track is a stopping place or the position of the head. Thus my Amdek drive is defined as a 40 track system (1 disc side). This is a little different from my understanding of the specifications provided with the drive, which indicates it has 80 tracks.
John’s SAFE system has been used extensely since the review was written. There has been no problems with it other than I damaged the special controller IC by zapping it with static electricity. There have been updates and revisions, and I am ordering a new EPROM that will provide a MOVE, to copy a disc from one drive to another, MOVE n to m to copy a file from one disc to another, and VERIFY. I have not implemented his fantastic SAVE system, but will do so very shortly. This will SAVE any program that will load into the computer! Just a press of a switch button. No LOAD command is used.
My apology to John, and I hope any reader turned off by my error will re-read my report plus others that are being printed. At least send for John’s literature and quotes. (Write to: The John Oliger Company, 11601 Whidbey Dr., Cumberland, IN 46229)