I raise

edit, actually, it might have been on the back...it's been forever since I touched one

I raise

edit, actually, it might have been on the back...it's been forever since I touched one

Big keyboard jack, serial for mouse, parallel for printer

Don't forget the serial input for gamepads and joysticks in the dedicated sound board for some reason
Except that wasn't a serial port, it was midi, and the reason it was on the sound card was because the input was analog.
Your joystick was just two fancy potentiometers, and your soundcard decoded the voltage on the middle legs into a position.
Soundcards handled joysticks because they had the fastest ADCs.
They didn't even use an ADC. They used 555 timers to produce a pulse. They measured the length of the pulse to determine the potentiometer position. Since there are 4 analog inputs, they typically used the 558 timer which is the quad version of the 555.
And here I thought I had it all figured out. But it does make sense. Doing it with an analog signal introduces noise and measuring pulse widths is going to be simpler.
More info: https://en.wikipedia.org/wiki/Game_port
The 15-pin D-sub connector itself was apparently a combination of analog and digital. It had to be, since MIDI is digital (it's right there in the name: Musical Instrument Digital Interface). TIL it wasn't all digital.
huh, i thought it was just because "owning a sound card" and "likely to play games" was the biggest overlap of the Venn circles.
Except that wasn’t a serial port, it was midi, and the reason it was on the sound card was because the input was analog.
Considering MIDI stands for Musical Instrument Digital Interface, I have no idea what you're trying to say.
Early PC only had 5 card slots, and the only jack on the motherboard was the keyboard. One slot is going to be used by a video card, one’s probably being used by a hard drive controller, one’s probably used by a parallel + serial card. Soundcards also included controller ports to try to save a slot.
I thought sometimes they called them game ports (for the joystick.)
I reasoned if you are installing a sound card, you are probably doing some gaming, so it made sense to sort of bundle those together.
And because the PC only have 1 serial port, you disconnect the printer and use a parallel to serial adapter.
Yes, this is where my PC master gaming started.
All the naysayers never used a Gateway AnyKey keyboard... their loss.
Such nice keyboards. My Gateway 2000 was from 1991 and I believe they were pretty top notch at the time. It wasn't until later that they went to shit. Through all the years and the massive amounts of mods, it didn't fail until I retired it sometime in the mid to late 2000's and only because home routers now did what it could do...faster and for a lot let power. It's still in storage and I bet that if I powered it on today, it would boot.
They all got bought by acer and turned into the shittiest brand-name PCs on the planet.
This one for me. Was born in 82.
Born in '88 and this was also my childhood. But to be fair, my parents bought the PC from Sears so it was probably an older, budget model. It ran Windows 3.1 and had a 16 MHz 386 with the Turbo button.
I got that reference. Fuck, I'm old.
Please explain? I get that the chubby bird is speaking assembly, but I'm sure there's more to it than that?
PS2 keyboards use interrupts rather than polling in USB, meaning every time a key is pressed the CPU stops what its doing to process it.
Cool! I had no idea it was deeper than just a physical interface change.
I'm wondering, is it still the case for mobos with Super IO?
And having to pick your IRQ when installing anything into your machine, and the weird bugs that could happen if you mucked it up.
Keyboard slows down the CPU because it gets priority over whatever the CPU is working on so the keyboard could cause your system to lag.
Back then all we had was single core CPUs.
In my day, the RJ-11 jack was for connecting the keyboard, not the phone line.

Okay that's something I had no idea about hahaha
The first three Macs had this jack in the front for the keyboard and a PC-like serial port in the back for the mouse. With the Mac SE and II, the switched to ADB, which looked like a PS/2 port, but you could daisy chain your mouse, keyboard, and other inputs like tablets or joysticks all into one jack in the back of the computer.
With the Mac SE and II, the switched to ADB, which looked like a PS/2 port, but you could daisy chain your mouse, keyboard, and other inputs like tablets or joysticks all into one jack in the back of the computer.
The port looks similar - both are mini-DIN - but ADB has four pins while PS/2 has six.
ADB was first introduced in 1986 on the Apple IIgs, and later was used in all Macs from the SE until the iMac. For the first few years there were two ADB ports, but in 1990 (maybe starting with the Mac IIsi?) they reduced it to one and started shipping keyboards with ports to daisy chain the mouse from.
The time of the classic "Keyboard missing. Press F1 to continue."
You know that thing that you don't have? You should press buttons on it.
Fuck you computer....
Way back, there were some rare keyboard / motherboard combinations where the motherboard couldn't detect there was a keyboard attached unless a key was pressed on it. That message was for those people with those combinations.
You pressed F1 and the computer would be like "my bad, there is a keyboard there, thanks for your help", or rather it would just shut up and boot.
The message could have been different but it had to fit in a small amount of BIOS ROM, so we got stuck with the one that covered all the bases the best, and unfortunately, most people who saw it didn't actually have a keyboard plugged in, thus, irony.
The error message sounds bad, but it was actually a good thing. A better phrased error message might have been "Keyboard missing. Connect a keyboard and press F1 to continue." But, in the early days every byte mattered.
The system wouldn't work without a keyboard, and if you get further into the boot process you might not be able to shut down cleanly if you didn't have a keyboard attached. That error message gave you a chance to attach the keyboard, or to troubleshoot why the keyboard wasn't being properly detected (like the plug got bumped and wasn't making good contact anymore).
It was annoying when the lack of a keyboard was intentional. Like, you wanted to use the machine as a server. But, AFAIK you could disable this check if you knew the machine was going to be a server with no permanent keyboard attached.
I was always told that you shouldn't (dis)connect a keyboard when it was on because it could short circuit and fry something. This was before USB, of course.
Starting around the time of USB, they started designing plugs so that the parts of the plug that carried power were slightly longer than the parts that carried data so that as you plugged it in, the power connected before the data. That wasn't something that was done with old connectors. In those, everything was the same length, so everything connected at once.
OTOH, USB is a more complicated protocol than the old serial / keyboard protocols. I think generally systems were built well enough that you were unlikely to "fry" something by plugging in or unplugging something like a keyboard while it was running. Especially because the keyboards used low current and low voltage. And computers used big discrete resistors, capacitors, etc. back in those days. But, you could get some bad data on the keyboard line.
Interesting stuff about the plugs, thanks.
I did quickly fact-check myself after posting and my brief reading suggested that it was possible to break the port, motherboard, or the peripheral, but that it was rare and more likely to cause corruption and/or crashes.
E.g. some anecdata in https://superuser.com/questions/172420/is-it-safe-to-hot-swap-a-ps-2-keyboard and https://electronics.stackexchange.com/questions/50883/why-some-computer-peripherals-should-not-be-disconnected-without-turning-off-thi
and more likely to cause corruption and/or crashes.
Yeah, that's the neat trick they basically solved by making the power connectors longer. If everything connects at the same time, you connect the data lines while power is still coming up, meaning there's a few milliseconds of data that you can't really trust. If the hardware and software on the other side is designed to "trust" the data from the keyboard, who knows what could happen. Probably not something that breaks the hardware, but definitely something that can result in unexpected data for the software.
But, just by adding a few millimeters to the power lines, you give a few milliseconds of power getting stable before data is attached, and that's enough for things to be nice and stable.
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