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Comment by raldi | Hacker News Reader

I love that the first boot screenshot at https://lh3.googleusercontent.com/-JB4VOj7FgnU/V-lCHIADrsI/A... says:

    Date and Time Unknown

Oh, you poor sweet computer, if we told you the answer, it would blow your little mind.

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I happened to come across the Alto's time handling code [1] while looking for something else. The Alto counts seconds since Jan 1, 1901 and the time can run until 2036 since it uses a 32-bit value. (Unix time in comparison runs from 1970 to 2038; it runs half as long because it loses a bit by using a signed value.)

The point of this is the Alto can handle dates until 2036, but will run into problems two years before Unix self-destructs in 2038.

[1] http://xeroxalto.computerhistory.org/Indigo/AltoSource/TIMES...

Good to see they at least thought some reasonable amount of time into the future; in contrast, the Apple Lisa, released 10 years after the Alto and a few years after the IBM PC, had an RTC that only went to 1995:

https://systemfolder.files.wordpress.com/2009/11/lisaem-date...

http://lisafaq.sunder.net/lisafaq-hw-io-cop421_clock.html

(Apart from this shortsightedness, the rest of the Lisa's design is also... interesting. Proprietary custom ICs, a pretty much locked-down user-is-an-idiot GUI, and complete separation between users and developers. It failed then, but unfortunately the same strategy is now considered the norm 30 years later...)

32 bit unsigned seconds spanning 1901-2036 is the same representation as NTP.

The PC had no RTC, so DOS would ask you the date and time every time you booted it:

https://en.wikipedia.org/wiki/File:PC_DOS_1.10_screenshot.pn...

...and if you accepted the default, as many people at the time did, it would be 1980-01-01 00:00:00. DOS and the PC actually had no Y2K problem, storing the number of years since 1980 in a single byte --- which will overflow after 2235. It is notable that there is no year 2038 problem either.

I'm not sure what the Alto's RTC capabilities are. Hopefully a bit better than the PC's?

Yeah, yeah, get me the EGA card/memory update that includes the Dallas real time clock!

It's always weird hardware combinations like that that makes me look batch at the early PC era and wonder what drove some of those decisions. Like all the sound cards that included a free extra ide controller for running CD-ROMs, you couldn't boot off them most of time but it meant you could play games and music CDs, assuming you had the correct extra audio cable to connect the two (many systems couldn't read the raw data fast enough to play without the drive doing the decoding).

And then I could swear at least one of my video cards added a joystick port.

Both of these make perfect sense. On early PCs everything was on a ISA card. Your parallel ports, serial ports, HD controller, floppy controller and video. Dallas RTC and video upgrade were probably the 2 most popular upgrades but you likely didn't have slots available for both, so putting both on a single card makes complete sense.

When sound cards came out with ide ports many computers still had ST-506 hard drives and not ide drives. Even if they did they might only have a single IDE port which was already being used or using it for a CD-ROM required on mounting your hardrive to switch master/slave jumpers on your hard drive. As since people at the time were installing sound cards for games and many need games requires CD-ROM drives the painting makes perfect sense. When soundcards with ports for CD-ROM drives first came out they weren't even necessarily ide ports. Some were SCSI or Sony CD-ROM ports.

In many cases you even saw the soundcards and CD-ROMs bundled together (and a pack-in demo CD or even a game) as that was such a common path to buy a computer, then upgrade it for sound and CD at the same time.

All of my joystick ports were on sound cards. As for the IDE controller, a lot of computers in the late 80s and early 90s only had one IDE channel, and it was pretty common to buy a sound card and CD-ROM at the same time (I remember the first ones my family bought were bundled in a "multimedia upgrade kit"). If you already had two hard drives, you were short on options, except that the sound card provided a solution.

Boggle. I'm amazed my old meat based brain can remember something like that 25 years later.

Probably will crash if you told it correctly. You know, the old Y2K problem. ;-)

As someone who was too young at the time, why would it crash? I thought the Y2K problem was just programs only storing the last two digits. So 2016 would be stored as 16 and displayed as 1916.

Yep, that's pretty much it.

You could run into crashes if something was dependent on the date being in the future since when the machine was built (and hence you get a negative number when you shouldn't have), or if the machine was alive between 1999 and 2000 (in which case the BIOS or applications may complain because you've gone back in time).

This /mostly/ affected date formats. Well built systems and programs measured time in seconds since the epoch on operating systems that supported that time representation format.

Many RTC chips used in PC's behaved weirdly when set to any year >2000 (resp. <80 or so). These behaviors included setting year to some fixed value, setting it to correct value but not incrementing date ever again and so on.

Yup, It will overflow its mind!

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