[INTRO]
So, in the last episode we talked about cassette drives, if you haven't seen that yet, I suggest
you go watch it first since it sets the stage for Floppy Drives. "Ahh! I love talking about
floppy disks! Right, so here's the thing. I don't care if they're 8 inch, 5 ¼
inch, 3 ½ inch, or any of the 3 inch Amstrad ones or any of the weird things in
between. For all over the world, I love collecting them, I love feeling them, I love looking
at them. Floppy disks are more interesting than pretty much any other older storage medium
to me." Technically floppy drives had been in use since 1971 in the business market,
usually in the form of these large 8-inch disks. These things were huge, and you can
see where they got the name floppy disk from. These are probably most well-known from the
movie WarGames, which came out in 1983. But interestingly enough, nobody was using 8-inch
disks in 1983. However, that doesn't necessarily mean the movie was wrong. It could just be
that he was given a 5 year old computer by his parents, which is not unreasonable I suppose.
In fact, the computer I use every day is 5 years old, so there's nothing wrong with
that. Also, according to Futurama we'll be using these in the future for video recording.
"Let's just see what you were up to last night. While I was asleep."
But the 5 ¼ inch floppy disk is what most people will recognize from the home computers
of the 1980's. Much smaller than the 8 inch, but still works pretty much exactly the same.
"So, when I think about floppy disks, what I really think about are the 5 ¼
inch floppies. When I had the 3 ½ inch floppies, I already had a hard disk and
so floppies sort of played a different role in my computing habits. But when I was using
the 5 ¼ jobs, that was really the only storage media that I had." So let’s
have a look at how these work. First of all, on the outside you have these "relief notches".
The purpose of this is to minimize any bending of the disk right around the read area. This
is the "index hole", which was monitored by a sensor so that the drive would know exactly
where the disk was rotation wise, but not all disk drives made use of this hole. This
is the "write protect notch". A sensor monitored this notch and if it was found to be open,
then the drive knew it was okay to write to it. If you wanted to protect your data, you
could put a sticker or piece of tape over the notch so the drive would not allow anything
to be written or altered on the disk. And since it was not a good idea to leave this
area exposed, a "paper sleeve" was used for each disk to keep them protected. Let’s
take a look inside and see how things work. The magnetic material is very similar to the
material inside of a cassette tape or VHS video cassette. It just happens to be round
and a bit stiffer. So this part of the disk was used for actual data storage. Now you'll
never be able to actually see the data on the disk, but if you could, here's how it would
look. Keep in mind that the typical disk had 40 tracks starting at the outer edge for track
1 and all the way to the inner edge for track 40. Inside of the disk drive, a "stepper motor"
is used to move the read head back and forth to access these different tracks. Now some
drives had sensors to help it figure out where the read head was, but some drives did not.
So if you ever noticed when you turn on an Apple II computer, the disk drives always
make this knocking sound. So, what's actually happening here is that the drive is first
powered on, since it has no sensor it has absolutely no idea where the head is. So,
the way to get around that is, they just send the command to back the head back to track
1 and they send that command 40 times, so it's guaranteed to be back at track 1. Once
the read head gets to track 1 it can't go any further so every subsequent attempt makes
a knocking sound. It does work, however, and does make sure the head always starts out
on track 1. Commodore drives are known to make the same sound when encountering a read
error or when formatting a disk.Now let's take a little bit closer look at how the data
is actually stored on the disk. In order to help figure out where files are stored on
the disk, the computer will divide it up into sectors. These sectors are defined entirely
by software and thus can be very different from one computer to the next. This is an
8-sector format, typical of the IBM PC. So if you asked for track 16, sector one you
would be reading from this area here. And if you could see the actual bits of data,
they would look kind of like this. Each dot representing a 1 and the blank area representing
a zero. Now, one thing you might notice is that a sector on track 40 is much smaller
than a sector on track 1. And yet, they store the same amount of data in this format. However,
other manufacturers handled this differently. Commodore, for example, used 21 sectors on
the outer tracks, then 19 sectors, then 18, and then 17 for the inner most tracks. As
you can see, this made the sectors similar in size and made more efficient use of the
disk space. Also Commodore had some other oddities such as using track 18 exclusively
for the directory. Also, Commodore disk formats did not use the last 5 tracks
on the disk, due to some quality problems with early drives. However, it was possible
to use all of the tracks with a custom format. Perhaps now it is a little bit more obvious
why computers during the 1980's of different manufacturers could not read each others'
formats despite being the same physical media. So, an Apple, for example, could not read
a disk formatted in a Commodore. Some systems, such as IBM typically used double-sided disks.
Now what that means is they used two read heads, one on top, and one on bottom. So they
could store twice as much data on a single disk, well sort of. You see, on Commodore
and Apple drives, you could turn the disk upside down to use the back side of the disk.
There's only one problem. See how the write-protect notch lines up over here. Well, when you flip
the disk around, the drive will now think that the disk is write-protected and won't
let you write anything here. The solution is to make another hole. Now they actually
sold products specifically designed to do this. But I would usually just take another
disk and use a razor knife to cut a slot out. Now you had a write-protect notch for
both sides, so you could use the full capacity of the disk. So let's talk about the actual
drive mechanisms themselves. Now, this is a typical full height drive that would have
been used by an IBM PC or an Apple or even a Commodore back when they were making the
PET. A few years later most everyone had switched to half-height mechanisms. Now check this
out. See how much larger a Commodore disk drive is compared to an Apple disk drive?
Why is that? So, Commodore and Atari took a very different approach to their disk drive
controllers. Let’s take a peek inside this Commodore 1541. Look at that huge circuit
board. Wait, what is that? A 6502 CPU, the same one used in the computers themselves.
And here we have two I/O controllers, exactly the same ones used in the computers, and 8
kilobytes of ROM, and 2 Kilobytes of RAM. So, it's very much its own self-contained
computer. Let me demonstrate this. This is a neat little program that makes your disk
drive play music. It accomplishes this by using the stepper mode for the head and vibrating
it back and forth. But the more interesting part is that you can now unplug the drive
from the computer and it will continue to do its thing all by itself, because the program
is executing internally.
[FLOPPY DRIVE MUSIC, WHAT A BLESSING]
Now, why did Commodore put a whole computer inside of their disk
drives? Well, my guess is that the probably did it to reduce cost. Because it was no longer
neccessary to put a drive controller inside the computer. And many of the computer users
were happy not even owning a disk drive and just using a tape drive instead. Basically,
with an Atari or Commodore, the computer doesn't even really know where the information is
coming from. It just sends a request out the serial port and says "I'm looking for file
XYZ." The drive will check the disk and see if it can find it. Once it does, it sends
the file back to the computer. An Apple does something very different. It has to send specific
commands to the disk drive telling it to move the head, spin the disk, and all of the decoding
of the tracks and sectors are handled by the computer's CPU. Now you might think that Commodore
drives should be much faster, than say an Apple or IBM drive because they had their
own processor on board. Well, it didn't work out that way, and in order to understand why
you have to go all of the way back to the Commodore PET. The PET disk drives were HUGE,
but they were decently fast because they used the IEEE-488 parallel interface. It was a
24-pin connector and had 8 pins for parallel data transmission. Well, when Commodore came
out with the VIC-20 a few years later, they decided to move to a serial interface where
data was transmitted one bit at a time. That wasn't necessarily a problem, since they were
going to use a hardware shift register, which would take care of this at the hardware level.
However, the hardware was faulty and it was too close to the time of release, so they
just did away with the shift register and instead just programmed the CPU to
address the data line directly, and it was pretty darn slow. And they didn't even use
the most efficient routine possible. But, that’s the kind of thing that happens when
you push design changes into a product at the last minute before it launches. Since
the VIC-20 only had 5K of RAM, it really didn't matter that much. But the C64 came out soon
after and had a lot more RAM. But they wanted to maintain backwards compatibility with the
disk drives for the VIC-20 so it ended up being VERY slow. "I remember my first impression
of plugging it in and loading up a couple of disk games, I was very very underwhelmed
by the actual speed of this thing. I mean, this thing was as slow and in some cases even
slower than the C2N datasette. And how could this be? I had no idea that a disk drive would
actually be slower than a turbo load on tape." Now, interestingly enough, people eventually
figured out how to make some more efficient, and thus faster software routines for communicating
with the disk drive. So cartridges such as this EPYX FastLoad came to market. All
this cartridge does is replace some of the kernel's disk drive routines. "This is the
EPYX FastLoad cartridge. And this is something that I would recommend to anyone that wants
to use a disk drive on a Commodore 64 with the original disks. This thing will actually
speed up loading times, 4 or 5 times. And this is very compatible; in fact it works
with every single disk I've thrown at my 1541." Commodore later sort of remedied this with
the Commodore 128 and 1571 disk drive. The combination of these two have very fast disk
access, but the problem is it is only fast when operating in native Commodore 128 mode.
But since most games were required to run in C64 emulation mode, the drive was just
as slow thus still requiring a fast-load cartridge. Now eventually we moved forward to the 3.5
inch floppy drives, and sometimes they were mistakenly called hard disks by people that
really didn't know anything about computers. Some of the first computers to use these were
the Amiga, the Macintosh, and Atari ST. Now, these guys were with us from the late 80's all the
way into the 2000's and apparently will even be used in the future to store robots' brains.
"I downloaded his brain. Everything that is Bender is right here: His mind, his memories."
It's basically the same technology just in a smaller, more durable casing, with a write
protect tab that can be moved on or off so you don't have to use a piece of tape. So
many of you may have heard that the US military still uses old floppy disks in some of their
specialized computers, like for controlling nuclear missiles and things like that. Well,
is that a problem? Not necessarily, you see those drives and disks were actually extremely
reliable back in the 70's and 80's. Of course, they also used to be expensive. A box of 10
floppy disks could actually set you back. In the 90's they started making them cheaper
and cheaper and the reliability suffered. And by the 2000's when the last batches were
being produced, they were total junk. The last few boxes of disks that I've bought, probably
around 2005, probably some of the last ones you'd find in a computer store, they were
actually Sony brand, a brand that you might think would be of high quality. And they were
total junk. In fact, 3 or 4 disks out of each box of 10 didn't work right. "One of the things
I think that people don't realize now is just how much floppy disks actually cost back then.
You know, you can go now to the store and you can buy like a spindle of 50 CDs or DVDs
for like $10. Which, I know they're also on their way out. But, you know, back when I
was a kid and I was using computers like in the late 80's and the late 90's, you could easily drop
$20 on, like a 10-pack of floppy disks. And really by that time, the price had already come down,
before that they were even higher. And it was expensive enough that I actually had to
ask for a box of disks for Christmas." I think because floppy drives and the disks had become
so unreliable towards the end of the era, I think a lot of people remember them that
way, even though they were actually pretty darn reliable back in their heyday. In fact,
I have plenty of disks that are like, over 35 years old and they still work just fine. "I've got
some floppy disks that have survived since the late 1979 from Heathkit systems and they're
still fine. On the other hand, I've got floppies from 1999 and they didn't last until like
2003 and they were done. Toast. And I lost a bunch of cool stuff. But, that's how it
goes. That's kind of a thing that's unfair to floppy disks. I think if you take care
of them really well, at least from the ones I've got in my collection, they tend to last
for a really long time." "As a retro computer collector in 2016, let me just tell you that
dealing with these aging floppy disks is a huge pain in the butt. However, there are
solutions like floppy drive emulators now that make working with these machines a lot
easier. But I have to say there is something comforting, and nostalgic about hearing. [FLOPPY DRIVE CLICKS] That
sound." And if you want to really appreciate floppies, just compare them to tape drives,
or even worse, to these old punch-tape reels that were incredibly noisy. Of course, floppy
disks were eventually replaced by optical media such as CD-ROM, which is a tale for
another episode some other time. But one thing I can say for sure is that the track/sector
concept we talked about earlier lives on today in magnetic hard drives only the data is so
much more densely packed. Now, I suspect in another 5 to 10 years, everything is going
to be solid state and think moving disks, like hard disks and stuff like that are going
to be obsolete forever.
Edited and improved by: OPGuyK