47 votes

Why were floppy disks invented after hard disks?

Floppy disks are harder to get right than hard disks. Early hard disks were enormous; the IBM 350 used fifty 24-inch platters. They were also rather fragile and cumbersome (heavy and power-hungry). To ...
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  • 96.5k
37 votes
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Why were floppy disks invented after hard disks?

While Stephen Kitt's answer already hits the core, I believe it needs a bit more history, as direct access magnetic storage did start quite a while before the IBM 350. Drums and Disks First there were ...
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  • 173k
25 votes

Should I use the internal or external drive for loading Amiga 500 games?

Amiga 500 1.3 machine only boots on drive 0 (DF0:) by default. There are programs that make it able to boot on DF1: but they're not really interesting because a lot of games either: have physical ...
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24 votes
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Were any external disk drives stacked vertically?

It seems to me that since disk drives are fundamentally horizontal devices that want to be wide rather than tall, To me they are taller than wide. After all, that's as well the orientation IBM did ...
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  • 173k
23 votes
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How did Commodore drives produce program listings from disk directories?

TL;DR: The computer, or rather its OS, has no idea about a directory, in fact not even what constructs a file. It can only open/read/write/close data streams from devices on the bus. Getting a ...
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  • 173k
21 votes

How did programs/patches stopping Amiga idle floppy drive noise work?

The sound came from the fact that drives would only report on the presence of a disk if the heads were moved. Thus by default, the OS would move the heads back and forth. Alternatively, the heads ...
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  • 1,743
19 votes
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Any difference between a VIC-1541 and a C64-1541?

Functionally there is no difference between the VIC-1541 and 1541. Internally, there may be lots of differences due to production variation and component variation. The thing to remember is that ...
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  • 1,053
19 votes
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Default (as opposed to physical) read/write heads - what are they?

The physical geometry how many heads the drive actually has is not the same as the logical geometry of how many heads is presented to the PC by the drive. By translating the geometry, the drive can be ...
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  • 17.9k
18 votes
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Where can I find an external 8-inch floppy disk drive?

As far as I'm aware there is no source of new 8" drives. If you do manage to find a working drive, there are a couple of options to connect it to a modern PC over USB: the KryoFlux floppy controller,...
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  • 96.5k
17 votes
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What systems used hard sectored floppy disks?

Hard sectored 8" and 5-1/4" floppy disks were used in some early computers including: DEC Pro 350 Heath/Zenith H-89a MITS Altair 8800BT NorthStar Horizon Vector Graphic computers Processor Technology ...
17 votes

Were any external disk drives stacked vertically?

Yes; this was standard procedure for at least the BBC Micro: Including for third-party drives: Presumably because two drives arranged that way were only just taller than the machine itself:
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  • 32.5k
17 votes
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Why was the 1541 so slow?

the drive could end up only being able to transfer one bit per horizontal blank = 63 microseconds. 1/(63e-6) = 15873 bits/s = 1984 bytes/s. That would be the bitrate during transmission within a byte,...
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  • 173k
15 votes
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How can a computer use the drive's momentum for emergency power?

Any real attempt to use the momentum of the spinning disk to generate power would cause the disk to come to a halt very quickly. In essence, this is the principle behing regenerative braking of ...
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  • 7,609
14 votes

How did programs/patches stopping Amiga idle floppy drive noise work?

Since at least Kickstart 2.0, the OS has built-in code that allows for drive checking without making the click noise. To enable it, just set the TDPB_NOCLICK flag in the tdu_PubFlags of trackdisk....
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  • 3,606
14 votes

How can I access an old pre-IDE disk?

That Conner CP-343 drive appears to be a special snowflake, but it's not. It's actually a standard IDE drive, with one exception. That 20-pin interface you're looking at isn't the IDE connector; it'...
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  • 4,052
14 votes
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Bootable floppies lock up with floppy drive connected via USB adapter

In the first phase of the boot process, the BIOS loads the first sector of the disk into memory and executes it. The code in this sector then uses the BIOS to load the code for the second phase, which ...
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  • 21.9k
14 votes
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Only "Drive A:" detected with two floppy disk drives

Unfortunately, you can't connect two floppy drives to the motherboard header on that system. Like most motherboards since sometime around 2002–2003, it only supports one floppy drive, probably because ...
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  • 96.5k
13 votes
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Why did the Atari 8-bit computers make beeping noises while accessing the disk and cassette drives?

The beep comes from the OS ROM, and it is actually derived from the timing of the start and stop bits of each byte shifted into POKEY, this is determined from the interaction of the interrupts ...
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13 votes

Obscure uses of the Commodore 8050/1541 disk drive

There were a number of programs that used the 6502 in the 1541 as a coprocessor. An obvious application was for calculating fractals, because that doesn't need a lot of RAM. An example is the ...
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13 votes
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What's the timeline of Commodore diskette drives?

You can get a relative ordering by looking at DOS versions for the drives. IEEE-488 drives 2040 - first drive, 5.25"x2@170K, 1979, DOS 1.0 3040 - 5.25"x2@170k in Europe, 1979, DOS 1.2 4040 -...
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12 votes

Obscure uses of the Commodore 8050/1541 disk drive

Playing music with the drive heads, of course. I've tried that too, wrecking the drive in the process. Dimming the drive LED, by flashing it very fast, with a variable duty cycle. Printing a file on ...
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12 votes

Obscure uses of the Commodore 8050/1541 disk drive

And now this: disk drive outputs the video signal through the serial bus connector! "Freespin" Demo by Matthias Kramm (Quiss/Reflex): https://www.youtube.com/watch?v=zprSxCMlECA Technical ...
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  • 260
12 votes

How do you send code to a Commodore disk drive and run it?

How exactly does one send a new routine to the drive and execute it? Usually by executing the Memory-Write command twice followed by UserN command, as described in chapter 8 of the floppy manual (*1)....
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  • 173k
12 votes

How fast are transfers between the C64 and the 1541 floppy drive?

Without any modification Commodore 64 Serial Bus operates at 3200 bit/s (*1). Effective maximum speed for C64+1541 is about 400 bytes/s. Sustained speed with turn around and alike is about 300 bytes/...
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  • 173k
11 votes

Why were floppy disks invented after hard disks?

Floppy disks solve a different problem from hard disks: They're cheap, and they're portable. A floppy disk (even an eight-inch floppy) slips into a brief case or a file folder in a way that reels of ...
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  • 1,844
11 votes

Should I use the internal or external drive for loading Amiga 500 games?

The Amiga 500 has a very console-like experience for the most part when it comes to games. Treat DF0:, the internal drive, like you would the cartridge slot of a Super NES or a Sega Genesis. Just put ...
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  • 246
10 votes
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Commodore VIC-20/64/128/16/Plus 4 floppy disk drive replacement

SD2IEC SD2IEC is a free software which turns an ATmega644 microcontroller into an emulated VC1541. It attempts a near-complete emulation (I think REL files aren't implemented, but nearly noone ever ...
10 votes
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Disk drive long storage, with or without disk inside?

Leave it empty. In floppy drives, the read/write head touches the disk’s surface, so leaving a disk inserted for long periods of time can cause problems — the head will tend to stick to the surface, ...
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