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> ... most commercial products on micro-computers were written in Assembly language, not a high-level language. This was done for performance. This was common.
by rogerbinns 12y ago
> ... most commercial products on micro-computers were written in Assembly language, not a high-level language. This was done for performance. This was common.
The exceptions were interesting. A common approach was a byte code interpreter/machine. This had the advantage of being easier to port, as you only had to port that piece rather than the whole app. Hardware used to be a lot more interesting back then with all sorts of variations on memory addressing modes, size of units of information (bits & bytes), overlaying (you couldn't fit all your code and data in memory at once), file access, and even something as simple as drawing text or graphics on the screen.
An example for games is https://en.wikipedia.org/wiki/SCUMM https://en.wikipedia.org/wiki/SCUMM
UCSD Pascal, and later large parts of Microsoft Excel (plus Word I believe) also used the approach, especially in the latter case because it needed less space - https://en.wikipedia.org/wiki/P-code_machine https://en.wikipedia.org/wiki/P-code_machine
Programming back then was very different to today. Virtually everything was constrained by cpu, memory and storage. Writing products involved working out how you could do things despite those, and debugging was not fun. Just like using 9 inch monitors, it seemed fine at the time, but now I really like having almost unbounded everything, and several freaking huge monitors!
- localhost 12y agoI'm pretty sure it was Multiplan and not Excel that used the p-code approach. Also, when Lotus 1-2-3 shipped, it was written entirely in assembly, was blazing fast, and crushed Multiplan in the marketplace.
- gcp 12y agoIt was Excel that used p-code. http://www.joelonsoftware.com/articles/fog0000000007.html http://www.joelonsoftware.com/articles/fog0000000007.html
- rogerbinns 12y agoRelevant except from that page: The Excel team's ruggedly independent mentality also meant that they always shipped on time, their code was of uniformly high quality, and they had a compiler which, back in the 1980s, generated pcode and could therefore run unmodified on Macintosh's 68000 chip as well as Intel PCs. The pcode also made the executable file about half the size that Intel binaries would have been, which loaded faster from floppy disks and required less RAM.
- localhost 12y agoThanks. Looks like both Multiplan[1] and Excel were p-code. However, Multiplan was wiped out by 1-2-3, and Excel ... adapted (it certainly isn't p-code today or anytime in recent history). [1] http://en.wikipedia.org/wiki/Multiplan http://en.wikipedia.org/wiki/Multiplan
- gcp 12y agoIronically, ironically... http://en.wikipedia.org/wiki/Lotus_1-2-3 http://en.wikipedia.org/wiki/Lotus_1-2-3 (Decline) "The inability to fit the larger code size of compiled C into lower-powered machines forced the company to split its spreadsheet offerings, with 1-2-3 release 3 only for higher-end machines, and a new version 2.2, based on the 2.01 assembler code base, available for PCs without extended memory. By the time these versions were released in 1989, Microsoft was well on its way to breaking through Lotus' market share"
- 101914 12y agoTheir motto was "Find the dependencies -- and eliminate them."
- tr352 12y agoSee also BASICODE, the "Esparanto for home computers". This was popular mainly in Europe, I believe. http://en.wikipedia.org/wiki/BASICODE http://en.wikipedia.org/wiki/BASICODE