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Comment Old-school asm and C programmers for the win? (Score 1) 152

I started PC programming in 1982, had to teach myself asm almost immediately in order to write a hardware interrupt handler for the serial port.
Back in those days code size was important, and for any driver/TSR type program it was simply crucial. Here in Norway we needed to load the KEYBNO.COM program which took over the keyboard interrupt and provided the official Norwegian layout, including the 'æÃÃ¥ÃÃÃ...' keys for our 3 extra letters in the alphabet.
Over the years, Microsoft/IBM had many version of this driver, the final one which also did text more font layout changes (at least for the default 25x80 mode) was up to 60 kB. This was large enough that lots of US-developed engineering/DB applications simply didn't fit, so I wrote a replacement:

All keys (including Ctrl- and Alt- modified combos) were handled, along with font remapping for 25x80, 43x80 (EGA only) and 50x80 (VGA only) screen layouts, using a total of 704 bytes. It became so popular that Compaq/HP stole it to give to their customers, then when we caught them red-handed (they had not figured out how to get rid of my startup Copyright message) they refused to pay but promised to not do it again.

Half a year later we caught them again, they had started telling customers that they had to keep it a secret.

Terje Mathisen

Comment This is a _very_ big deal! (Score 5, Insightful) 63

NIST have always been the world leader in creating ever more accurate clocks, the current masers work in picoseconds and below, so allowing the reference to drift by 4.8 microseconds means that precision dropped by at least 6 orders of magnitude.

If allowed to propagate to the GPS control clocks, this would have been enough to totally destroy the navigation system since a clock that is off by 4.8 us corresponds to a position error of 1500 kilometers. (OTOH, USNO has its own large ensemble of atomic clocks, so they don't depend short term on NIST updates.)

Full disclosure: I worked with the NTP Hackers (network time protocol) team for 20+ years, so I'm probably a bit more interested in precise timekeeping than most. I have personally soldered together 4 or 5 GPS-based reference clocks that would deliver 25-35 ns RMS precision.

Comment As a programmer: Quake (Score 1) 228

Full disclosure: I was somewhat involved with the Quake development, helped Mike Abrash a little bit to optimize the asm code that actually made a pure SW 3D rasterizer fast enough to be playable.

The Castle Wolfenstein - Doom - Quake progression might seem from the outside to be a fairly linear upgrade path, but in reality Quake was at least an order of magnitude harder to achieve.

Just the number of amazing ideas John Carmack managed to come up with in order to make a real 3D game possible will forever give Quake a special place in my programming heart.

Terje

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