The “Stand-up Mathematician” Matt Parker finds (parts of) one of the surviving Burroughs 220 machines, in a somewhat surprising place https://www.youtube.com/watch?v=XZy3rXr2yeM (around 07:15 mark, if you don’t care for math, you brute)
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I wonder… it should be perfectly possible to replicate the feat described in that paper, using an 8 bit Basic on an 80s retro computer. Probably we’d have more speed and more capacity by quite a long way. We might even be able to draw a wire-frame… in fact that might be the easier part…
All we need to do is figure out how to compute the volume of a polyhedron given the vertex coordinates…
From The Burroughs 205 and 220 Blog
Both architecturally and electronically, the 220 was quite similar to the 205. It was still a decimal, vacuum-tube design. The 220 retained the 205’s 11-digit word format, instruction format, and numeric representation. Core memory replaced the drum. Memory sizes could range from 2,000 to 10,000 words in 1,000-word increments. A typical memory size was 5,000 words. There being no drum, the clock was supplied by an oscillator circuit, and at 200 KHz, was only slightly faster than the 205’s 142.8 KHz rate.
Also from that blog, a room-sized 220 installation:
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More on the 220 in Unisys History Newsletter. (Volume 5, Number 2 April, 2001 by George Gray):
Approximately fifty-five B220s were built. The price ranged from $640,000 to $1,209,000, depending on the amount of memory and the number and type of peripherals. … the average monthly rental was $17,000.
An unknown Air Force programmer on the B220 at Randolph had written a system in which the data on a tape could be of arbitrary format and length because it was preceded by program code which could extract the data. This distant precursor of object oriented encapsulation came to the attention of Alan Kay (then an Air Force programmer) who later developed the Smalltalk programming language.
Programming on the B220 was done primarily in assembly language. Burroughs provided an assembler in 1960, known as STAR 1. It allowed for the use of alphabetic mnemonics (ADD) in place of the numeric op-codes (12) and provided a rudimentary form of relative addressing. Data items could be grouped into regions and relative addressing done within the region, so that 0050010 would be address 10 within region 5. Another assembler called BLEAP was written at Stanford University. ALGOL was the principal higher-level language.
In 1960, a group at Burroughs led by Robert Barton and Joel Erdwin wrote a compiler called BALGOL. It was used extensively on the 220 at Stanford University, where over 80 percent of the programs were in ALGOL. The remainder were written in the BLEAP assembly language. The ALGOL compiler was so fast, a Stanford official said, that programs were usually recompiled each time they were run.
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As the author of the aforementioned blog post, I’m please to see some attention paid to the 220. I suspect the picture in the post is of the 220 at Stanford University, so it’s interesting that Bill Hedges mentioned in Matt’s video his 220 pieces were from that system.
Note that his console has been modified to serve as a movie prop. The 220 used neon bulbs, which are bright enough for people, but not for film cameras, so the original lamps have been replaced with either incandescent or LED bulbs.
I’ve written an emulator for the 220 that attempts to recreate the console layout and approximate the look and feel of the peripheral devices and their controls. We have a small amount of software for it.
To my knowledge, the BLEAP assembler has not survived, but Don Knuth donated a listing of the BALGOL compiler (which was based on ALGOL-58) to the Computer History Museum in Mountain View, California.
I was able to transcribe the assembler listing and after many adventures get it to run. That compiler was really something in its day, and remains an impressive accomplishment. It had a big influence on Burroughs – it was a major factor in their decision to build the B5000/B5500.
Everything is publicly available at the emulator link above. Documentation is available at https://bitsavers.org/pdf/burroughs/Electrodata/220/.
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The size of the old machines are impressive. To think today all that computing
power could fit into the numeric keypad shown there.
Just a decade later (1968) a desk top calculator could replace the
much of that wall space (1958). Sharp Compet 22
I picked this example, because it is also programable.
An interesting find, for sure. But see how very expensive and limited the programming memory was - memory being the most difficult and the limiting development, in the history of computing, for a very long time.
The calculator has a socket at the rear for connection to a “memorizer” for converting it to a programmable calculator (see photograph below). The model 30 memorizer provides 30-program steps and sold for US$305, and the model 60 memorizer provides for 60-program steps and sold for US$444[1]. The memorizers would also work with the Compet 32, 33, and 50.
I wish the language would have been ALROG, not ALGOL.