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43

It's hard to know for sure with just that picture, but that's a Mersenne number and a prime one at that. When a mathematician writes a Mersenne number on a board they are not thinking about getting all the digits. By far the most interesting and likely question computationally speaking would have been "prove that the number is prime". That could be used as ...


30

Update: It seems as if David Marshall has found the missing link: The footage used in the clip is not just from the Manchester Baby, but also from the Manchester Mark 1 which became operational about a year after. As noted its first (useful) program was in fact a proof for Mersenne primes, a perfect fit for the chalkboard scene. Looks like the combined ...


12

I've found three programs which together make up quite a comprehensive test suite. 8080/8085 CPU Diagnostic, version 1.0, by Microcosm Associates Diagnostics II, version 1.2, CPU test by Supersoft Associates 8080/8085 CPU Exerciser by Ian Bartholomew and Frank Cringles The assembly of the Microcosm tests, and compiled COM programs of the other two tests ...


9

Back when I started in the late 1980's, we still had test suites and test cases. It's just that all the tests were carried out by hand. Unit tests were pretty much unheard of - the developer just did some ad hoc testing before checking his (it usually was a he) code in. Then there was formal testing that was structured into several tiers. You had your ...


8

Klaus Dorman's functional tests for the 6502 are fantastic: https://github.com/Klaus2m5/6502_65C02_functional_tests


7

PAGE and HIMEM are what you might call "system variables" in BBC basics, they mark the bottom top of the memory available for Basic use, they are intiialised from OS-provided values but can be changed by the user. On a regular BBC micro HIMEM will point to the bottom of screen memory, so it can change if you change screen modes (this BTW meant you couldn't ...


6

By late 1983, Apple developers had developed an almost complete Apple Macintosh OS and were working on software for it. MacWrite and MacPaint were pretty much feature complete but still needed a lot of testing, especially in low memory conditions. MacPaint needed to allocate three off-screen buffers, with each the size of the entire screen, so it was ...


6

Admittedly, your question is way too broad - Even today, that question cannot be answered for the bandwidth of what commonly qualifies as "software". Embedded Software requires (and required) an entirely different test strategy and, obviously, the approach to testing safety-critical software like a moon lander will be entirely different from that of a home ...


5

The 64KB of RAM for the 65C102 co-processor is provided by eight MB8264 64k x 1-bit chips. Each chip provides one bit of memory for every address, meaning that all eight chips are used for every memory location. In many instances, the failure of a RAM chip will affect all memory locations (including the 6502's page 0 registers), meaning that the co-processor ...


4

Agree with tofro, a broad question with no simple answer and depends on how critical the application was and the budget. c1982, writing assembler (2650) for a TV video games console, if the game could be played and no-one could crash it, make it do something odd, or get strange displays or sounds, then it was good to go. For the most part if anything at all ...


4

IIRC, there were conformance tests (input decks with known outputs) back in the day of FORTRAN programs on punched cards.


3

I am unaware of any formalised test suite for either the 6520 or 6522. The 6526 is at least partially covered by Wolfgang Lorenz's C64 test suite. Because of the applicability to other machines, you usually see it documented for its 6502 tests (and the outward link to the suite itself there is broken; instead try that listed here) but it includes a ...


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