[HN Gopher] 12-minute Mandelbrot: fractals on a 50-year-old IBM ... ___________________________________________________________________ 12-minute Mandelbrot: fractals on a 50-year-old IBM 1401 mainframe Author : winkywooster Score : 20 points Date : 2020-12-24 00:25 UTC (1 days ago) (HTM) web link (www.righto.com) (TXT) w3m dump (www.righto.com) | sliken wrote: | Only somewhat related, in 1986 or so computer labs at University | of Pittsburgh had giant printers, like 8 feet long with a maze | like paper path. They were however rather fast, something like | 60-90 pages a minute. The pages being spit out was a common sound | in the labs. They were however overwhelmingly used for ASCII. The | first page would be your username spelled large on the first page | out of ASCII. | | I got interested in the Mandelbrot set, wrote it in pascal from | the original Scientific American article. Trick is I had no way | to view it. File quotas on the campus VAX were limited, so I | wrote a simple RLE compression. I looked into the Postscript | standard so I could write it myself, but was somewhat horrified | at the complexity. I had written PCL before. But I did find a | nice Fortran library. So I wrote some Fortran to read the RLE | picture file and output PostScript. | | Some afternoon near Xmas, I tried it out. I had no idea if it | would work since I couldn't debug it, there was no postscript | viewers (or graphical terminals) available. I printed the | postscript file and the printers sudden page per second stopped. | After a few seconds the operator jumped up and was about to reset | the printer. I pleaded my case for a few minutes, the operator | agreed, and a 300 DPI Mandelbrot was spit out. The operator went | "Woah!", a few more people in the lab saw it and impressed. I | explained what a fractal was and that you could zoom in | infinitely. Several people wanted copies, so I printed them. The | entire process took many minutes (pascal to generate, fortran to | render, and print to print). These days you can zoom way deeper | and get at least 60 FPS. | | Later I wrote a EGA driver in Turbo Pascal, primarily for | Mandelbrot viewing and a few simple games I wrote. I was able to | do so from an article in the PC Tech Journal which printed the | entire EGA card spec. Later I wrote the ASM for an 8087, then a | HP-730 (PA-RISC 1.0) and a small tweak for the HP-735 (PA-RISC | 1.1). | h2odragon wrote: | > additional instructions were available for a rental fee | | The wet dream of chipmakers today, no doubt. Most recent example | that occurs to me is the VideoCore bullshit on Raspi, afaik the | effect was few paid for a license and that hardware feature | mostly went unused before it went obsolete. | kens wrote: | I should point out that the additional instructions in the IBM | 1401 required additional hardware, so you weren't paying for | IBM to move a jumper. | | For instance, the multiply/divide feature cost $333 per month | (in 1960s dollars), but it required the installation of 183 | circuit boards (each the size of a playing card) so you were | getting your money's worth. | | More curious was the Sterling currency option, which provided | arithmetic in pounds/shillings/pence. (I.e. 12 pence to the | shilling, 20 shillings to the pound.) This required 508 new | circuit boards, but made it much easier to do currency math in | England. Keep in mind this is transistor circuitry to do math | in hardware. | walshemj wrote: | After a substatial hardware upgrade though - those of us who | are old enough remember when IBM PC's came with a empty chip | socket for the Intel 8087 | colejohnson66 wrote: | You mean the hardware license keys for the MPEG-2 decoder? That | was very stupid, but I bet it was something the Raspberry Pi | people had to do to make the board cheaper (probably through | cheaper SoC). So rather than paying (fake numbers here) $5 per | processor IC, they paid $3 with the decoder option available. | | It sucked at the time, but thankfully the later Raspberry Pi 3B | was powerful enough that that wasn't needed anymore (it was | still available on the 3B, but IDK about the 4B). | userbinator wrote: | ...and there is a crack available for that, not surprisingly. | wolfgang42 wrote: | (2015); discussed at the time: | https://news.ycombinator.com/item?id=9243163 ___________________________________________________________________ (page generated 2020-12-25 23:00 UTC)