Folklore.org: Square Dots

from Jef Raskin on January 30, 2004 18:52:29

Because Andy wasn't there, he doesn't know the full story. Originally, when Ken Rothmuller was in charge of Lisa, the project was a character generator-based machine. I spent a lot of time convincing him and his engineers that what was needed was a Mac-like bit-mapped architecture. Ken was fired, at least partly because he didn't use the Jobs-approved hardware character generator approach. Woz had said that a processor couldn't keep up with the demands of generating characters graphically. I demonstrated to Woz that it could be done on even the Apple II, presenting assembly code and timings that I had worked out. When I was fighting for square dots (alongside Atkinson, who understood fully why we needed them) I would point out that you didn't want a photograph to change appearance when you rotated it. For many at Apple the idea of displaying and rotating a photograph was novel. In any case, the Mac was square dots from the very beginning of my proposal. When I was a Visting Scholar at the Stanford AI Laboratory, in the early 1970s (pre-Apple) we already had live video and computer graphics on our systems. When I first met Woz and Jobs in their garage (in 1976) I told them about this kind of computer applications and about the interfaces at PARC. But Jobs just brushed it all off, saying that really good ideas will never come from big companies or universities.

from Andy Hertzfeld on January 30, 2004 19:29:44

Jef, I did a lot of research for these stories by talking with Bill Atkinson and others for hours, especially about the stuff that happened before I started at Apple in August 1979. According to Bill, the Lisa had a bit-mapped display from its inception. In fact, the bit-mapped display existed before the rest of the Lisa, in the form of an Apple II card with a 720 x 360 display that Bill used to prototype with. Almost everyone concurs that Ken Rothmuller was fired because he didn't like a mouse-based user interface, not because he didn't like the graphics. But I think I did neglect to give you credit for the Macintosh having square dots, since I know it did from the very beginning, even before Burrell got involved.

from Ken Krugler on March 10, 2004 18:01:53

Rich Castro did come up with a new version of the video timing chip that controlled the screen resolution, so that a Lisa running MacWorks could have square dots. Unfortunately you could no longer use the Lisa office software with the new chip, because the super secret Lisa copy protection serial number was hidden in that video timing chip.

from joe snyder on May 01, 2004 01:20:08

See the letter at http://www.semaphorecorp.com/ss/ss23.html which mentions a $79 switch that adjusted Lisa's aspect ratio for Mac software.

from Bill Coleman on May 13, 2004 22:08:20

In late 1984 or early 1985, there was an Atlanta-area electronics consulting firm that was looking into producing a kit that would allow the Lisa to have square pixels. When Apple cancelled the Lisa in 1985, nothing became of it. Although MacWorks did look distorted, for many run-of-the mill uses, it wasn't so bad. After a while, you got used to it.

from Ray Arachelian on June 17, 2006 15:07:23

Minor nit-pick. It's 720x364 for a non 3A ROM Lisa. Works out like this: 8 bits/byte, so 90 bytes across by 364 lines, which fits almost perfectly in 32K. 720/8*364=32760. Another bit of trivia, if the color in that last bit isn't black, the Lisa screen looks terrible, because you can see the vertical retrace lines. :) The screen modification kit that was released with the Mac XL (3A ROM + video state ROM + transformer) turned the screen into a 608x431 display with square pixels. Just out of curiosity, was the serial # hidden in the video chip for tempest reasons? (i.e. would the video/sync signal include the serial number?) Supposedly in the UK, they use TV detector vans that look for the tempest signals from TV's. Was wondering if it was possible to build a Lisa dector van. :-D

from fornext on July 07, 2012 21:41:10

To clarify a technical detail. Andy said:"The designers decided to endow Lisa with twice as much horizontal resolution as vertical, using a 720 by 360 pixel display, with pixels that were twice as high as they were wide." If the pixels were "twice as high as they were wide" then at 720x360 the active screen would have been square. However, the active area on the Lisa screen had a 3:2 aspect ratio, 50% wider than it was tall. Each rectangular pixel must actually have only been 33% taller than it was wide, a width to height ratio of 3:4, not 1:2. Wonderful site, great book (Revolution In The Valley) and insanely great computer. -jm

from Phoebus66 on March 19, 2013 10:16:44

Not that this didn't send intergalactic waves through the universe but in 1985 I woz (re)inventing the algorithm needed to assign note (frequency) and tone amplitude envelope (ADSR) timings to x amount of tone generators (set of a VCO/VCA synthesizer) coming from a 88 keys musical instrument keyboard. I later implimented it on a Z80 processor. The idea was to develop a sound sampler but that didn't took off. Years later I saw the introduction of the Emu EMAX II commercial sampler exactly as I had in mind 8 years before. Bought it at approx. 115 thousand belgian franks in 1993.

from John Post on February 25, 2022 22:06:06

When the MacXL came out, Apple sold a kit that converted a LISA to a MacXL by swapping out the ROMs and adding a flyback transformer.I had the idea while at university (Cal Poly) to make a daughter board for the Lisa that housed both sets of the ROM, and enable one to run the machine as either a Lisa or MacXL. A simple toggle switch flopped the flyback in and out, and used the tri-state pins on the ROMs to select which to use. I was working in the terminal repair shop at school then (anyone remember the teleray 10-T?), and my colleague there, John Byrne, and I started a small company to make and sell them, Orphan Technology. We sold a few hundred, I think, before we sold the balance of the stock to sweet old Sam Neulinger. Not bad for a Mechanized Agriculture major.

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