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Hard drives have read/write heads which fly above the spinning disks when the drive is powered. When power is removed, the heads no longer fly... For a long time now, the arms which hold the heads have been designed to “auto-park” the heads away from the disks’ surface, or over a safe “landing zone”, when they lose power¹, but early (up to the mid 80s) hard ...
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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 go from a hard disk of this sort to floppy disks required a number of developments: in particular the ability to remove the platters (which came in 1962 with ...
37
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 drums. Drums were huge cylinders with a magnetic surface, and a separate head for each track - something that would have been rather impossible with a disk. ...
32
My question is if you can fit X number of tracks on a 3.5" platter, why not use the same density on a 5 1/4 platter and have even more tracks? I know there are tradeoffs like latency due to head-travel or cost / complexity if you tried to put multiple heads on the same platter-side but in any case you end up with a capacity that is unobtainable with the ...
21
I cannot state for certain that it required a hard disk, but using AutoCAD (v1 released Dec.82) without one would have been awkward to well-nigh unbearable. The program itself was huge for the time and used countless data files. I can't imagine running it from floppy.
Even if v1.0 could do so, by the time v2 or v3 was released HD had to be required. It ...
18
If "a more modern machine" includes systems with ISA, PCI or PCI Express slots, it should be easy enough to retrieve the data from the drives. You'll need a SCSI adapter (known as a host bus adapter, HBA); you can find loads on auction sites, or SCSI4ME and other places (depending on which country you live in). Adaptec cards are very good and well-supported ...
18
The ST-238R shown in the image is an RLL (Run Length Limited) drive and will not work correctly with a standard MFM controller, although it has the same ST506 electrical interface and cabling. To read back your data, you will need an RLL controller, which unfortunately are less common than MFM controllers and might not be easy to find.
RLL is an encoding ...
16
I started working for a newly-certified IBM PC dealer in the UK at the end of 1984. IBM thought we would be selling about 50% twin-floppy PC (PCG) and 50% XT with 10MB hard drive.
In fact, I'm not sure we ever sold a PCG. Perhaps it's because we were focused on accounting and payroll applications for small businesses - not something you would consider with ...
14
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's the connector between the drive mechanicals and the controller board that would normally be mounted to the bottom of the drive. Why it's not affixed to the ...
13
This is a SCSI device, so it shouldn’t be too hard to get the data off the device. You need the following pieces of equipment:
a SCSI controller, known as a host bus adapter (HBA); these are available for most buses, including USB (getting rare though), PCI and PCI Express (the last two are still easy enough to find, especially second-hand; expect to pay a ...
12
You’re running into compatibility issues with very old drives. In this particular case, your drives are new enough to support the ATA “identify device” command (which is how your hwinfo input includes the drive’s names), but there’s something going wrong with the “read capacity” commands. I suspect the reason is that these commands are LBA-based, and your ...
11
The order of switching should be relatively arbitrary - After all, there were Ataris around (like the Falcon or ST/E) that didn't have a separate power switch for the hard disk and where it was relatively random what stopped first.
But, if in doubt, ask the manual. The Atari Megafile manual says the following:
(I'm especially fond of the "...when the ...
11
You can check the Whole Earth Software Catalog; I remember it listed a few apps as requiring hard disk. It came out in 1984, which would have been pretty early. For example DESQ does (pg 114). It's not a database btw, but a window switcher/proto-gui type of thing. Real World Accounting on pg. 103 is another, and there's even a program called Great Plains ...
11
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 half-inch magtape and punched card decks just will not do; and if somebody asks you for a copy of that report you're working on, you can hand them a floppy disk ...
10
The easiest way is to get an external USB enclosure or USB-to-IDE adapter. IDE-to-SATA adapters exist, but they require opening up your computer to install.
When selecting hardware, keep in mind that IDE (PATA) hard drives come in two common varieties: "desktop" (usually 3.5" form factor, with a 40-pin data cable and a 4-pin power cable), and "laptop" (...
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
Like you said, seek time and latency are longer for larger-diameter platters. Another factor higher is power usage at start-up due to inertia. Lastly, for mature technologies smaller is very often cheaper to manufacture.
9
In all the BIOS setups I was dealing with that have similarly 47 drives to chose from the first or the last one was editable directly in BIOS SETUP for manual settings. Sometimes the manual settings was done in different menu entry (near formatting utility ... but beware do not accidentally format IDE !!!).
IIRC DOS uses BIOS routines for HDD access so if ...
9
This command is supposed to place HDD heads on "park" position.
8
The Honeywell Series 60 Level 62, and its successor, the Honeywell Bull DPS4, certainly used variable-length sectors. It is worthwhile pointing out that these products were designed as IBM System/360 and System/3 knock-outs.
The disk drives themselves did not care what size the sectors were, and you could create sectors of various sizes on a track, or you ...
8
ProDOS provides a common device driver API for storage systems, but does not specify a partition table format. Rather, the SCSI (or other) HD interface card has firmware to map partitions to ProDOS volumes.
The Apple SCSI Card and Apple High-speed SCSI Card for the Apple ][+, //e, IIGS utilize the Apple Partition Map, just like with their Classic Macintosh ...
8
Bus: yes should negotiate.
Device size: possibly okay. If your OS can issue (and your scsi controller supports) a read(16), then you'll get the full capacity. If it only supports read(10), then it'll look like a 2TB volume (assuming the drive is bigger!). I've heard of some random old controllers that didn't support read(16) and caused problems for big ...
8
The hard drive is so old that it pre-dates the era of auto-detecting the drive parameters. If the USB adapter cannot determine the correct drive parameters automatically then there is no way to force the parameters. Connecting it to a PC where you can manually set the drive parameters in BIOS is the fastest solution. The standard drive parameters should be ...
7
Nop. 1500 USD was resale for the drive. Just for the drive.
But noone - at least noone with a tie - bought just a drive.
The mentioned Apple 'drive' was a Apple Profile, a complete setup including disk, controller and power supply in a case plus cabeling and a interface card. Not to mention the software (inside and drivers for SOS/DOS). All at a retail ...
7
When the battery died and reset the system, could this have reverted the
BIOS to an earlier version that did not support the hard drive?
No. BIOS is a motherboard firmware program which is usually written to a ROM, PROM, EPROM or EEPROM. It does not a working battery to maintain the information stored in this fixed memory.
It does store volatile ...
7
Smaller platter sizes let you fit more individual drives into the same space. Then you can setup RAID-5 or 6 to keep the data online when a drive or two fails (this also reduces the need to restore from backup), or you can use RAID-0 if your primary objective is performance. And because you can join multiple drives together to achieve larger volume sizes, ...
7
Larger radius = lower RPM, which makes pretty much all timing specs worse.
The Quantum Bigfoot was limited to 3600 RPM. Why not spin faster, like a Cheetah X15 (15 kRPM)? Flutter and buffeting. Halving the radius gives four-times reduction in these effects (assuming no spindles -- real platters are on spindles and the coupling to these spindles provides ...
7
In 1981 I acquired an IBM 5444 from an old mainframe computer. Luckily I also got the service manual for it, and so was able to design a controller board to interface it to my Sinclair ZX81. The interface circuit only used about a half dozen TTL chips and was quite simple, but the ZX81's clock frequency was slightly too low so I had to disable the drive's ...
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