Category: storage

PCMCIA

Pcmcia-type-ii-and-iii

PCMCIA is based on the EIDE architecture found in desktop personal computers. By using a smaller connector with power and other signals, it allowed the use of solid state storage other other peripherals to be attached. In Japan the JEIDA standard competed with PCMCIA so in 1991 after some pressure from industry the standards were …

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HARDCARD

hardcard

The IBC PC usually had a single floppy drive. Quantum realized some machines could used an expansion card to add storage. The original Quantim 10MB hard card was $1095. The earlier Xebec Owl 10MB disk was released in August 1984 with a 5¾” disk and a SASI controller on a card. Quantum introduced the hardcard with …

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RODIME RO352

RODIME RO352

The Rodime RO352 is he first hard disk available in the 3½” format. This disk cost $1,895 when new in 1983. 11MB ST506 interface 306 cylinders 4 heads 17 sectors 306 landing zone type 02 3600rpm The Rodime RO0352  is a ST506 MFM hard disk in the 3½” format . There are two models in the series, RO351 …

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HARD DISK ERRORS

mfm hard disk

Occasionally hard disks run out of spare sectors. Often those errors arise after a few years of use. It is best to format the disk and then check the media to be sure all of the bad sectors are mapped. This way Windows can continue to use the disk for general use. FORMAT Generally format …

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SEAGATE ST-225

st-225

The Seagate ST-225 is a 20 MB hard disk. ST-412 20MB Data rate 5 Mbit/sec Seek time 85ms Platter capacity 10.5 MB AT drive type 2 Heads 4 Spin rate 3600 RPM Actuator Stepper Interface MFM Form factor 5¼” half-height This disk has not performed well with RLL controllers. We suggest MFM controllers which is …

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HARD DISK CAPACITY

Vendors use a decimal system on top of a binary one. They do this to make their products look bigger. Most disks present data using the binary system, sectors are 512 bytes however modern high capacity disks are now using 4096 byte sectors driven in part by the master boot record limitations and also to …

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HARD DISK LIMITS

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One of the most frustrating problems a lot of DIY enthusiasts came up against was BIOS problems that prevented the use of larger capacity disks. In the early days, DOS version 1 which came on a floppy with our original PC could not even use directories. All saved files had to be saved in …

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SEAGATE ST-412

102672976p-03-07

The Seagate ST-412 is a 10 MB hard disk. ST-412 10MB Data rate 5 Mbit/sec Seek time 85ms Platter capacity 5 MB AT drive type 1 Heads 4 Spin rate 3600 RPM Actuator Stepper Interface MFM Form factor 5¼” full-height

SEAGATE ST-506

102672976p-03-07

The Seagate ST-506 is a 5 MB hard disk. ST-412 5MB Data rate 5 Mbit/sec Seek time 85ms Platter capacity 5 MB AT drive type 0 Heads 2 Spin rate 3600 RPM Actuator Stepper Interface MFM Form factor 5¼” full-height

THE HARD DISK

Back in the early 1980s the use of a 32-bit MBR index was believed to adequate. Hard disks from the 1956 to 1981 had not even made it much past 1GB with mainframes. The IBM 350 Disk Storage Unit (image), released in 1956, consisted of the magnetic disk memory unit with its access mechanism, the …

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