Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!linus!genrad!decvax!harpo!seismo!hao!hplabs!sri-unix!MBF@cmu-cs-c From: MBF%cmu-cs-c@sri-unix.UUCP Newsgroups: net.micro Subject: none Message-ID: <2232@sri-arpa.UUCP> Date: Thu, 16-Jun-83 13:43:00 EDT Article-I.D.: sri-arpa.2232 Posted: Thu Jun 16 13:43:00 1983 Date-Received: Sun, 19-Jun-83 15:04:32 EDT Lines: 54 From: MBF First, on the Apple keyboard: Since many system designers, Apple probably included, simply arrange their keyboards as 8x8 (or some such) matrices of keys and scan them, the only way they can get "true" n-key rollover would be to put a lot of diodes on the keyboard matrix to prevent the "key aliasing" syndrome which occurs when three keys depressed simultaneously "look like" a fourth key. No matter that the software polling algorithm really DOES implement true n-key rollover (or 8-key, in some cases); the software simply cannot tell the difference between 3 or 4 depressed keys which are vertices of a rectangle in the keyboard matrix. This phenomenon occurs only for certain key combos, of course, resulting in an effective 3-key rollover capability; a shame, since I find 4-key to be pretty much what I need. Frankly, I find that I type MUCH faster on a well-designed electronic keyboard than I am able to on any traditional electric typewriter; thus it's no surprise that a "traditional" (mechanical) typist is unfamiliar with the concept of rollover - his painfully slow typing style was developed on a rollover-less keyboard! Aside: I've personally standardized on the keyboard layout with which I've found I can do the most per keystroke: the VT-52/VT-100/Human Designed Systems/Heath H19/etc.. layout, which is sort of an extension of the basic selectric layout and a departure from the standard low-end tyewriter layout. I wish everyone agreed with me; however, in the meantime, I am soliciting similar and differing opinions on this practical issue. What's your favorite keyboard? Why? On another issue, the bits and pieces I've picked up on the new, $600 Coleco machine are that it is basically an in-house design - no big OEM subsystems - with lots of shared components and bare-bones engineering (read "economizing", not necessarily "cheap"). My personal opinion is that it won't be a serious contender in the under-$1000 pc/hc market, largely due to a serious case of the Commodore-itis: hardware and software engineering executed by a technical group seemingly devoid of experience with serious computers. Admittedly, all of the machines in this price category have varying degrees of congenital head injury, but some, like the Ataris and to some degree the TI, show at least a measure of integrated systems engineering as if they were designed by people who wanted to be proud of their efforts. But this is a religious issue...and unfortunately, clever marketing plays entirely too much a part in successfully selling large quantities of incompletely designed microcomputer systems (and everything else, for that matter). flames 'n' busses, Mark Dzmura via mbf@cmu-cs-c p.s. I wonder how the Atari hackers, for all their basically sound design, implemented a rollover-less (sounds good, eh?) keyboard? I can't touch-type on the stupid thing withou missing letters!!