IBM 5100 APL: Nested Emulators

A discussion about Raspberry Pi performance prompted this:

IBM 5110 Emulator - Javascript on Raspberry Pi
IBM 5110 Emulator – Javascript on Raspberry Pi

From the inside out:

Starting the show takes 17 seconds from clicking the Restart button (second from right, top row) to APL’s Clear WS prompt. I have no idea how that compares with a Genuine IBM 5100.

I distinctly remember writing APL programs, but that’s about as far as my memory will take me. [sigh]

9 thoughts on “IBM 5100 APL: Nested Emulators

  1. That bring back memories. My fingers still remembers most of the keystrokes.

  2. Ah, APL. That takes me back. When I was learning, I had access to a Tektronix 4015 terminal (the kind that used a flood-storage CRT as memory, as RAM was expensive in those days) with an APL character set ROM. I was allowed to use it because I had been able to repair its bizarre little screen printer. I hadn’t thought about APL in a while, but it came up in a recent conversation about implementing Kalman filters, when someone wondered if there was a programming language that had baked-in matrix math support.

    1. bizarre little screen printer

      IIRC, it required thermal paper so sensitive you had to store unused rolls in a refrigerator.

      I used 4015s, back in the day, with rolls stored near the air chiller output under a raised floor, of which IBM Poughkeepsie had many. Mark One misunderstood Purchasing’s Unit of Measure and bought approximately one semitrailer of paper; pretty nearly every raised floor in the building had a cache of Tek thermal paper. Some may be puzzling people to this day…

      1. Oh it was weird photosensitive (3M 777 “dry silver” paper) that was also thermally sensitive. It was really thin paper too, like onionskin. The printer worked by scanning a line across the CRT, and copying the data to a bizarre 1-line CRT (the faceplate was like 2cm high and 35cm wide), and then transferring that light via fiber optics to the paper. I enjoyed working on that funky printer just so I could examine the strange CRT and optics.

        1. Yeah, that shakes loose some sediment: makes all my inkjet printer hassles fade into triviality!

    2. Good old fashioned BASIC – before Microsoft got their mitts on it – has matrix mathematics built in. ANSI standard BASIC (“Full BASIC”) still has it. A couple of free implementations are Decimal BASIC and Michael Haardt’s bas.

      1. Actually, pre-Microsoft, there were two flavours of basic. There was HP BASIC, which was the nice one where you could make substrings by accessing strings as arrays of characters, and GE BASIC, which was the clunky one with the silly LEFT$(), RIGHT$(), and MID$() functions to extract sections of strings. Microsoft started with GE BASIC, then tweaked/removed a bunch of stuff in their implementation.

    3. We used 4014s for CAD work (IC layout) until the early-mid ’80s. Looks like the ’14 was a cousin to the 4015, but graphics only. It had a proper dimming circuit, unlike the poor 4010 where somebody left it displaying a circuit graphic far too long. You could see the circuit with the terminal off. I got it as scrap and used it with a Heath H8 for a while.

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