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62

Forty years ago, a 7MB file would be unheard of, at least in contexts where floppies would be the only available means of transferring it. (Tapes were commonly used for large transfers on minis and mainframes.) In slightly more recent times (even thirty-odd years ago, and then as long as floppies were still useful), we used archiving tools with support for ...


34

Gameboy games use a CR2025 battery which over the years eventually dies stopping games from saving and causing previously saved games to disappear. Note however while the game is powered you can still save, however once you power down the save will be gone. In order to replace the battery you must open up the cartridge with a 3.8mm screwdriver security bit. ...


26

As well as splitting across multiple floppy disks, there were several cabled communication options available ranging from your basic serial cables and sending data over via X/Y/ZMODEM or Kermit, but there was also specialized parallel cables (like printer cables) that could be used that facilitated even faster transfers. I think "LapLink" was a such a ...


24

40 years ago - 1978 - there was no home/hobbyist/small office computing to speak of. Maybe a few hundred people altogether. So you must be talking about commercial/industrial computing. For large files we used 1/2" mag tape: You've seen drives like this in older movies: These tapes could hold one hell of a lot of data: Maybe 50Mb. (Really high ...


17

Gameboy games use CR2025 battery, which will die and take all the data with it: It's lost for good. Saved games back in those days were preserved through the use of a battery right in the game pack, not stored on the gaming device itself like it is today. And when that battery dies, so does the saves with it. It's not about corruption of the save or ...


14

Do have a 7 MiB file, you would need a HD at least that size. In reality even a manyfold thereof, as usually one won't have a HD with just one file. Now, in the real early times, lets say 70s, home users wouldn't have disks at all - not even floppies, and professional users with minis would use disk packs (exchangeable hard disks) and maybe fixed disks of ...


13

I don't remember what the memory density was compared to today's SD cards. No, today's flash offers a way (several magnitudes) denser storage, but it is also way less reliable. What happened to bubble memory - is it still being sold? It might be still around. Today bubble memory is a rather special niche market with most uses in military and space ...


13

Magnetic Bubble Memory (MBM) was a technology that never found a sustained market, and was only briefly in vogue a couple of times in the 1970s and 1980s when market and technical issues hit other storage technologies. While MBM is non-volatile and fairly rugged, it has a few show-stopping disadvantages, including: It needs to be heated to over 30 °C ...


10

Your timescales are out. Floppies might have just existed 40 years ago, but your average office worker never saw one. More to the point, office workers didn't pass machine-readable data around the office to each other, the only equipment they had that could read the data was a shared mainframe, so they would both access the same copy. From Gio Wiederhold, ...


10

The short answer is MS-DOS 3.3. According to the MS-DOS Encyclopedia, MS-DOS 2.0 to 3.2 (included) only supported one MS-DOS partition per partitioned device (hard drive basically). (Before MS-DOS 2.0, hard drives weren’t supported at all.) MS-DOS 3.3 introduced support for multiple partitions per device, albeit still limited to a single primary partition ...


10

ZIP drives come with many different types of interfaces. The most prevalent were: Internal ATAPI version, most commonly installed in PCs. (An IDE version also existed, but was rather uncommon.) External Parallel port version, most commonly connected to PCs. Internal SCSI version, most commonly installed in early Macs. External SCSI version, most commonly ...


9

It appears that there are several versions of both DoubleSpace and DriveSpace. Information about each version as I find get it will be posted in this answer. DoubleSpace DoubleSpace uses MRCI, which uses "a variant of Lempel-Ziv encoding".[2] A non-technical explanation of the DoubleSpace compression algorithm: DoubleSpace first identifies the repeated ...


9

The story is told in this 1988 usenet post by Paul Homchick: Some time went by and it was a CP/M world, and diskettes were bigger. In 1981 Richard Greenlaw released SQ and USQ, based on Huffman encoding and written in BDS C. This was the first popular compression technique. Greenlaw gave away the binaries and source code. <...> By 1983 it ...


9

The difference between 360KB and 500KB is not entirely due to space between sectors. A lot of the difference is due to clock sync bits, sector identification markers, checksum/ECC bits, etc. Keep this in mind otherwise comparisons are meaningless. Taking the DEC RP03 disk pack drive as an example of an "early hard disk", I took a look at the maintenance ...


9

It doesn’t need to be loud, it needs to be unshielded. Many speakers produced in the last 20-30 years are shielded, to avoid their magnets affecting surrounding objects — particularly CRTs (you don’t want your speakers changing the colours on your retro TV screen), but as a side-effect, magnetic media too. If you have unshielded speakers with strong enough ...


8

DECtape was used that way; it was wide (0.750 inch?) magnetic tape, on very small reels, so it didn't take forever to find a sector. PDP-8 and PDP-11 systems from Digital Equipment were the likely systems sporting DECtape drives. The tape was fully redundant, took a LOT of wear without losing data, and that made it suitable for such system-program use. ...


7

Which OS? Using a Unix or variant, we used cpio, which would detect end of media (tape or floppy) and prompt to replace and continue onto (or from) another volume. The media was just treated as a sequence of blocks of data. If using MSDOS, there was BACKUP and RESTORE commands that spanned floppies but I’m not sure if they were in DOS exactly 40 years ...


7

Experimentally verified data retention duration: 0 seconds. Because you asked and I was curious too, I have just cut an ED notch in one of my old HD disks (to trick the drive into thinking it were an ED disk) and tried to format it in my ED disk drive set on my Sinclair QL - It wouldn't even format. The drives have no problem whatsoever in handling both ED ...


6

40 years takes us back to the dawn of "Personal Computing". In June 1978 Apple released the Disk II for its Apple II computer. It was based on the Shugart SA-400, the first widely available 5.25" drive. Prior to that there were only 8" floppy drives. That would take up quite a bit of desk space. There weren't many files larger than a disk at that time ...


6

A few years ago I've tried to ressurect a few of my cooler floppies that had bad sectors and couldn't be formatted on my Amiga 600. My approach was to leave them on my strongest speaker for about a day, then flip, and leave it for another day, then reformat and write. Surprisingly, I've got a few of those fixed that way, but I doubt that leaving a floppy for ...


6

The Amiga can support multiple mass storage controllers, subject to the following necessary limitations: Any time multiple controllers are using AutoConfig, each controller must correctly support the AutoConfig protocol. This means it must pass the token to other controllers on the bus so that each controller gets a chance to configure itself. Each mass ...


6

I can't find any info whatsoever. Most likely that's just a standard SCSI case (like Ross Ridge already assumed), notable due the existence of a terminator and an ACSI to SCSI cable (maybe even a homed made one). Being a rather standard drive it no hits may turn up in conjunction with Atari - in fact, there where zillions (almost) of shops that created ...


6

Caviar, as a word, is associated directly with luxury. That's most likely what the marketing focus group were thinking when they put it forward as a possibility. Most likely only one possibility of several, which were then selected by C-level executives. Relatively few people know what the eggs actually taste like.


5

MS-DOS 6.0 and 6.20 shipped with DoubleSpace. MS-DOS 6.21 removed it due to the Stac lawsuit, and MS-DOS 6.22 replaced it with DriveSpace with an incompatible algorithm and format. Soon after MS-DOS 6.22 was released, MS signed a settlement with Stac and Windows 95 shipped with an unified driver that supported both. And yes, they decided to default to ...


5

ProDOS, being an 8-bit OS designed to run in 64K, uses very small and efficient internal data structures to map logical entities, like your volume /HARD6 to physical hardware entities. Specifically, ProDOS maps its block devices (all disk drives) to unit numbers that are 1-byte long with the high 4-bits specified as DSSS, where D is the drive and SSS is the ...


5

First you need to make sure that your CF card and adapter are working properly. One easy way to do this is to boot from the hard disk and make a boot floppy (FORMAT A: /S). Copy the FDISK and FORMAT utilities to the floppy. Power down, remove the hard disk and install your CF card and adapter, then boot from the floppy. Partition and format the CF card ...


5

I am just guessing here (as I am used to ZX platform instead of yours). MIC input that is not a good idea. Mic input might have a band pass filtering circuitry that could mess up with the serial feed of yours. Also the coupling is different as Mic is either passive component which requires source current from the recording device or an active one with very ...


4

The RAM is the means of (relatively) persistent storage. Even when the device is "turned off", the contents of RAM are maintained using battery power. Power to the RAM is provided by the main battery, and by a "backup battery" that's there specifically to keep your data safe when the main battery is dead, or while it's being removed. If the backup battery ...


4

7MB? What an unwieldy thing in an era when RAM was 4-64kB (not hard limits, just a sampling of values). Other answers have not touched on acoustic coupling modems and BBSs, which were methods of file transfer in the late '70s. (How could you make an acoustic coupler have dimensions fitting all shapes and sizes of phone? It's easier when there's a model ...


4

It doesn’t, at least not in any particularly useful way. Because of the position of the density sensor cut-out on ED floppy disks, they’re detected as 720K floppies by HD drives. Their contents can’t be read, but they can be reformatted as DD disks...


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