From FORTRAN to Fireworkz One programmer’s voyage through the 1980s and 1990s Stuart Swales Formerly of Acornsoft and Colton Software September 2020 Sparking an interest • I first became interested in computer systems through electronics as a teenager • Various electronics magazines sampled • In 1976 I stumbled upon “Electronics Today International (ETI)” • Subscribed to ETI for many years ETI System 68 • A modular Eurocard-based system • Supported several microprocessors, with board designs for the Motorola 6800 and SC/MP • Designed principally by John Miller-Kirkpatrick • Articles ran from April 1977 • Sadly I had insufficient cash! • “The annotated listing of the monitor PROM is available on request”. Hmm... • 20p well spent — my first exposure to software! Still interesting, though • Motorola M6800 Microcomputer System Design Data guide A snip at £2.00 from NewBear Computing Store at the NEC BASIC at 300 baud • My maths teacher at school began an Open University course that year which involved some ‘online’ computing • We had an ASR-33 teletype (with punched paper tape of course) and a phone coupler • The Open University system was a Hewlett Packard (System 10?) located in Newcastle • The HP had a BASIC interpreter, and that was well documented in a HP manual supplied with the course material • School were happy for me to use it at lunchtime Increased potential • In 1978 I’d taken on a part-time job at Tesco (other supermarkets are available) stacking shelves • Cash was accumulating quite quickly • Could I buy a system now? Er, no. • Commodore PETs and Apple IIs had come on the scene but everything still seemed way out of my league Ohio Scientific Superboard II • And one day in early 1979 I spied an advert for this system... • 1 MHz 6502 • 4 KB SRAM • Decent keyboard • Cassette interface • BASIC ROMs • Keep saving!!! Programming the 6502: Rodnay Zaks • All those 6502 systems looked good, so I thought I’d better get prepared for the day when enough £s had accumulated! • ISTR another 6502-based micro system in a mag had just published its EPROM content but just as a hex dump and of course that needed investigating... • So...send money to Sybex Ohio Scientific Superboard II • Then the day came when I thought I had enough £s so went for a demo • Who could want more? • Me, obviously, as I spent the extra £40 to max out the SRAM to 8 KB! • That’s only £10 per kilobyte, folks... Programming the 6502: Stuart Swales • Naturally, the first program one writes is a disassembler out of curiosity • Somewhere I still have my Superboard II monitor ROM annotated listing neatly typed out – I know that it’s in this house in a red folder! • I think that I got a payment from the OSI UK service agent for a copy of this listing and that of the loadable extended monitor code Programming the 6502: Stuart Swales • The Superboard II had character-based graphics, with some useful ‘graphics’ that included a ‘tank’ in eight orientations and a two-character composite ‘Starship Enterprise’ • I wrote a few games for my amusement, including the mandatory lunar lander • I did sell a few copies of the games and disassembler on cassette tape, advertising in Computing Today (an ETI offshoot) Cambridge • I went to Cambridge to study Natural Sciences (Physics, really) in 1981 • IBM System/370 Model 165 – Phoenix OS • This is where I got to write FORTRAN code for the first time and play with plotters • Great to discover the huge range of useful routines available in the NAG library • You could even have a whole one megabyte process limit if you asked nicely PRIORITY EXCEEDS 255 - PLEASE LOGOFF • A useful side-effect of joining the C.U. Physics Society was that you got extra resource allocation on the IBM • However, you could still easily run out... • Discovered quite early on that even if your remaining resources were too low to allow you to log on interactively using a terminal, if a job was submitted via the punched card reader, it would always run it Who is this person? • A friend from college, Tony Thompson, who was doing Computer Science, had borrowed my compiler book • Tony’s Computer Science supervisor, Jeremy Bennett (from Acornsoft Languages) spots an unfamiliar book on Tony’s shelf and leafs through it • There is an unfamiliar name in the front cover... • Who is this person? • Why don't I know him? Just the ticket! • In the summer of 1983, between the second and third years, I was down in Cambridge doing the ‘Long Vac’ summer labs at the Cavendish Laboratory • Tony gets me to meet Jeremy Bennett • Acornsoft have a FORTRAN IV (66) compiler written in BCPL that they’d like to target the BBC Micro • FORTRAN? Tick • BCPL? Tick • 6502 assembler? Tick • Great stuff — when can you start? • Introduce yourself to DJ-D and see you then! FORTRAN – I was a BCPL compiler • Acornsoft Languages were then in the process of publishing the two-ROM BCPL system for the BBC Micro • I think the FORTRAN compiler was too large for this BCPL system to process • My job was to translate the FORTRAN compiler from BCPL directly to 6502 assembler • There was a new macro assembler for me to use: MASM, written by Jon Thackray at Acorn BCPL – what’s that? • BCPL (‘Basic Combined Programming Language’) originated in Cambridge and is a forerunner of the C language • Aside: an article in Acorn User once helpfully expanded the term BCPL as ‘Byte Protocol Control Language’ Back to FORTRAN • Acornsoft’s overspill office — where I was to work for the rest of the summer break — was in Green Street, Cambridge, and not too far from Market Hill • A few weeks in, and just as I’d begun to make good headway with the FORTRAN project, Jeremy Bennett announced that he’s off to do a PhD: “A methodology for automated design of computer instruction sets” He later became a Lecturer in Computing at the University of Bath, authoring the textbook “Introduction to Compiling Techniques” Enter PMF • That was when Paul Fellows arrived on the scene to become the Acornsoft Languages Group Leader • Paul had written tons of software published by Acornsoft for the BBC Micro, including Sphinx Adventure and the S-Pascal compiler Fun with 6502 Second Processors • At this point we only had one 6502 second processor at Green St. I needed to use one for MASM, and there was someone else working on a large LISP system • Sharing a second processor isn’t fun • So I paid a visit to the stores at Acorn Fulbourn Road armed with the parts list for a 6502 second processor • The very helpful chap showed me the system in stores and left me to the task of grabbing all the bits needed and signing them out • Soldered it all up and was happy • Apparently someone from Acorn rang Acornsoft a few months later asking for ‘Mr Swills’ as they weren't happy – employee not found in system! Progress with FORTRAN • I’d made a decent stab at getting this going in the time available, so Acornsoft were happy to lend me a system to continue working on it in my spare time during my third year at Uni • For some reason I can’t remember, I ended up with TWO BBC Micros (one with Tube) in my room, much to the delight of friends who would call round to play games Gainful employment? • I joined Acornsoft full-time in September 1984 in the Languages Group, working for Paul Fellows once more • Paul had already recruited another programmer to the group, Richard Manby • Tony Thompson joined as well! • We’d work together as a group for almost four years Betjeman House • Acornsoft had recently coalesced back under one roof, on the top floor of Betjeman House, at the top of Station Road. Nice spacious offices. Luxury indeed • Acornsoft Languages had the office in the furthest corner, and overlooking the Botanic Gardens • There were often squirrels in the trees to distract you • Luckily I’d rented a flat only ten minutes walk away and could cut through the Botanic Gardens • If I was early, the main exit gates wouldn't be open • No problem, you could just nip through the bushes and jump down a small wall, surprising the people working in Logica on the ground floor FORTRAN • I was still developing FORTRAN, finishing the compiler then onto the run-time system • Tony Thompson did the floating point support code and the linker/loader • We did seem to get less time to work on this as the months passed though • I think this drew to a halt when we realised that it was always going to need a 6502 second processor to compile anything useful, and the market wasn't there • Also, as far as I remember, we hadn’t started any user documentation either! More languages • Acornsoft continued to publish language products thick and fast, several externally written such as COMAL and Micro Prolog Credit: Paul Fellows ISO-Pascal • ISO-Pascal was written in-house at Acorn by Ben and Li and published by Acornsoft in 1984 • Full implementation • BSI certified • Compiled to interpreted BL-code Termulator • Or, don’t believe a word they say • I had done a simple text demo for the front photo on this pack • “Can you make it more interesting?” • Yes, but... you can see its now 40 characters not 80 • “Oh, you won’t see that on the finished product...” Credit: Centre for Computing History Master testing – to destruction? • Acornsoft Languages managed to obtain an early prototype board of the Master (internally called Project B at that point) for compatibility testing on condition that we hid it well • As well as putting it in the furthest corner of our room, in the furthest corner at Betjeman House, it was screened off behind some partitions • We also thought it would be a good idea to disguise it by putting it in a BBC Model B case • That's when we discovered that the prototype board didn't fit • Out comes the hacksaw, cutting enough of the back of the case off • We didn't have anything to hand that'd cut across the base plastic, so that's when I started to kick the back plastic out having cut it some more to weaken it • And of course that was when DJ-D wandered in..