The author’s guesswork fails him

Debunking More revelations from TMR!

Before we start dear reader, your correspondent was in Manchester over the weekend to look after half a dozen 8-bit systems he was exhibiting at Play Expo; he’s not fully recovered from said outing just yet and apologises in advance for any potential mistakes or typos that might possibly sneak into this post but, as an aside, here’s a photo[1] of Clone Invasion running on one of your correspondent’s two C64s in the event hall.

Clone Invasion at Play Expo

C64CD demo Clone Invasion running on a C64 at Play Expo in Manchester.

In his recent post on the blog “C64 Crap Debunk” called “Release Notes – Clone Invasion” which you can read on , TMR has done again exactly what I wanted him to by offering even more revelations about how some people were able to program the C64, although it had a totally crappy BASIC and not very detailed documentation from Commodore.

Most of the techniques used within Clone Invasion are covered both in Commodore’s own documentation for the C64 and third party books such including those released either before or during 1984 and the rest, such as using the upper/lower border areas, were worked out by bedroom coders and disseminated either by word of mouth or through disassemby of existing code. If the author really wanted examples of “how some people were able to program the C64” there are ridiculously large numbers of those already available but admitting those exist would debunk quite a bit of what he’s posted over the years.

Of course, TMR has recently criticised Atari again for holding back a few details about their original Atari 400 and Atari 800 models, which were released in 1979, for two years. I think this was before many people had computers, so they weren’t affected.

And this is, of course, a bogus argument on a number of levels; by 1979 the home computer market in America was already significant in size so this wasn’t “before many people had computers” and, even if that were the case, we’re also talking about something significantly more than merely “holding back a few details” as well so the number of people affected is irrelevant. Quoting from the part of Steven Levy’s book Hackers for a moment;

The Atari was a “closed” machine. This meant that Atari sequestered the information concerning the specific results you got by using microprocessor assembly-language commands. It was as if Atari did not want you to be able to write on it. […] John [Harris] would write Atari’s people and even call them on the telephone with questions; the voices on the phone would be cold, bearing no help. John figured Atari was acting that way to suppress any competition to its own software division. This was not a good reason at all to close your machine.

This is very obviously in a completely different league of nefariousness than even the more fantasy-based claims made by the author of either Commodore or Jack Tramiel but, despite not having actually done research to know how much information was unavailable or how it impacted would be programmers, the author still arrogantly feels that he’s somehow equipped to make claims about the effects on users. Actual Atari 8-bit programmers who tried to learn around that time such as John Harris have voiced their annoyance at Atari’s actions; Harris himself is credited with writing one of the first third party titles to really use the computer’s hardware but that was after a long-winded process of trial and error reverse engineering the secrets out of Atari’s programs, something that the majority of programmers wouldn’t be capable of.

But lets just pause to consider for a moment dear reader; the author’s fixation on 1984/5 is also two years after the C64 debuted in the United Kingdom and there would have been far less computer users here than in America during 1979 and yet the author moans despite Commodore releasing documentation when, by his “logic”, they were apparently allowed to keep it to themselves. Once more the author manages to debunk his own arguments in bulk.

Atari did supply the excellent Atari BASIC with these computers, which had commands for their colour, graphics, and sound, the most important aspects of computers for a lot of people. There was the option of buying an Atari 400 without the BASIC cartridge, but this could be bought separately later on

This is a either a deliberately misleading or very poorly researched couple of sentences; Atari withheld information on far more than just the player/missile graphics so important, major features used by developers all the time such as user defined graphics or display lists were also hidden away. There aren’t even commands from BASIC to handle these features to even hint that there was something to be discovered and, even with documentation, it would have had the author “practically in tears” since it’s done with POKE commands like on the C64.

TMR has recently confessed to first of all reading a book about 6502 Assembly Language, but which wasn’t specific to the Commodore 64. This must have made things more difficult, not including information such as where the screen RAM is located, or any details of a routine to print out a character.

Not particularly it didn’t dear reader no, the C64’s user guide covers most of what your correspondent needed to know such as the location of screen memory or the basics of utilising the hardware sprites and the C64 PRG covered everything else.

It was also included in Commodore’s own “Commodore 64 Programmers’ Reference Guide”, which contained hardly any information about Machine Code/Assembly Language.

With “hardly any” in this particular case actually meaning a hundred pages on the subject from over four hundred pages of reference book (or more if we include the relevant parts of the appendices or the memory maps) including a list of 6502 opcodes with a description of their functions and addressing modes; there’s also a list of ROM calls  including CHROUT which prints a character to the screen.

Dear reader, it almost seems like the author hasn’t actually read any of the book or indeed the manual since he keeps making these half-witted, incorrect comments; if that were the case, his opinions on the quality of the content he hasn ‘t properly read should be treated with the contempt it truly deserves.

TMR has refused to supply a flowchart for “Clone Invasion”, but has supplied all the source code. This runs to 861 lines or perhaps only 687 “SLOC”, meaning minus the blank lines and comment lines! From that, we can safely say that this isn’t an example of how someone could get started writing demos on the C64. It would require a lot of study and creating some much simpler programs before getting on to this.

So where exactly is the author getting the information from to make this claim dear reader, it certainly isn’t from his own personal experience since he hasn’t actually learnt to program the C64? And, although your correspondent never claimed Clone Invasion to be an example of how someone could get started, the author doesn’t have the first clue how close something like Planet Invasion or your correspondent’s copy are to that point so is, in essence, lying to his readers by leading them to believe he has that knowledge.

You can always consult TMR’s nine part series “The Hex Files”, but this ends on a cliff hanger, although he said there were more articles which he seems to have lost. I think these would be available through a request to The British Library, which seems to have an archive of all magazines and newspapers published in Britain.

Your correspondent commented previously that the Hex Files was “written for C64-specific fanzinewith the important word that the author didn’t bother to read correctly highlighted. And even somebody able to use Google should be able to find other options or one of the dedicated C64-specific forums or sub forums to ask for advice – it really doesn’t take much effort to find these things but the author seems unwilling to put that legwork in for some reason, possibly because these resources demonstrate how wrong he is.

[1] Unlike the author, your correspondent doesn’t have any issues using his own digital camera!

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