SPD EEPROM Specification
In addition to the description of the transmission interface, I2C information, the PC SDRAM Serial Presence Detect (SPD) Specification specification defines the information recorded in the EEPROM by the manufacturer.…

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Excellent coprocessor (FPU)
This time it turned out with a floating point. In time, apparently, they lured the team of Dirk Meyer, one of the creators of Alpha 21264. Now the floating point…

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How to choose additional equipment
An important place in the LAN of the office is occupied by the wiring closet. The cabinet itself does not directly participate in the work of the LAN, but it…

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Design Features of the Zip Drive Head Drive

Unlike HDDs, the Zip drive uses a linear drive with a moving coil. There are two types of drive mechanisms for moving coil heads: linear and rotary. These types differ only in the physical arrangement of magnets and coils.

The drive with a moving coil is an electromagnet. Its design resembles that of a conventional loudspeaker. When a current of a certain polarity flows, the coil moves in or out of the gap of the permanent magnet. In Zip, a movable coil is rigidly connected to a block of heads and is placed in the field of a linear permanent magnet. The coil and magnet are not interconnected in any way: the movement of the coil is carried out only under the influence of electromagnetic forces.

The linear drive used in the Zip drive moves the heads in a straight line, strictly along the radius line of the disk. Its advantage is that when it is used, there are no azimuthal errors characteristic of a rotary drive, but there is a significant drawback: the head block in such a mechanism must be massive enough, and to control it, you need, accordingly, massive enough and, most importantly , powerful, engine.

Due to its “heavy weight category”, and, accordingly, the inability to work fast enough, the linear drive cannot be used in modern HDDs.

In the production of hard drives, a rotary drive is used, which works on the same principle as a linear one, but in it the ends of the head levers are attached to the moving coil. When the coil moves relative to the permanent magnet, the head movement levers rotate, moving the heads to the axis or to the edges of the disks. Due to its low weight, such a design can move with great acceleration, which can significantly reduce the data access time. The rapid movement of the heads is facilitated by the fact that the shoulders of the levers are made different – the one on which the heads are mounted has a large length.

The probability of failure of devices where a massive linear drive is used is much higher than that of devices with a rotary drive (respectively, the use of a linear drive in a Zip drive can also cause a malfunction such as a breakage of heads).

How is the Y2K controller
Despite the fact that such controllers are now produced by many companies, this type of equipment does not shine with a variety of technical solutions. Pay attention to the appearance…

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Novell High Availability Server™ (NHAS)
NHAS allows you to use Intel architecture equipment as part of two servers and a shared disk array connected to them. By pairing two independent servers in an Active /…

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Intranet no problem
Out of the scope of the article, issues of software selection and technical details of network configuration deliberately remained. These issues must always be addressed specifically for a particular customer.…

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DIMM EEPROM test program dimm.exe
A quick analysis of the type of DIMM module installed in the system unit can also be done with dimm_id.exe. The program is subject to all the restrictions discussed above:…

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