Hello, dear readers of the magazine,
la 'REALTIME'! In the 'Hardware' section today
you can learn a lot of useful information
tions about hard drives: what is it, why
is it needed and what does it look like from the inside. Speech
will mainly talk about internal hard drives -
rah, but you can also learn about other
ny existing species. Which of us even
since I haven’t heard this cherished word and
users have seen more powerful ones
computers. Of course, the family of computers
terov ZX-STRUM has come a long way in our
country over the past 3-4 years and now
It is not uncommon for a computer to have accumulated
bodies on floppy magnetic disks. But time
and progress cannot be stopped. Already now
although not many have it connected to the ZX-STRUM
It's a wonderful thing - a hard drive. And
this is not luxury or anything at all
not a necessary bloat, but a very useful thing
and necessary. In addition to the fact that on wine
chester you can record a lot of information
characteristics and speed of this device
is many times faster than the operating speed
with floppy disks, without a hard drive it is impossible
can work in fully functional
computer networks. So above the question
Having a hard drive in our computer requires
but think about it. And now a little history.
The first computers, like the tabulation tables that gave birth to them,
tori, usedfor storing information
tions of punched tape and punched cards. Actually,
there is nothing surprising in this - magnetic
new technology has come to this area
only in the 60s of our century. First
time most often used accumulative
whether on magnetic tape and magnetic drums
nah. Then the first magnetic
disks, which became the progenitors
modern hard drives and floppy disks.
Many design details made them similar to
today's HDDs (drives on
hard magnetic disks - hard drives),
since the disks were really "hard-
mi" and were collected in a package, however, like
modern floppy disks (flexible disks), they
were absolutely not protected from dust and other
various atmospheric influences. Then the disks
occupied an intermediate position between
belts and drums according to many parameters -
frames: capacity, access speed, cost
storing a unit of information. Real
the revolution took place in 1973. Developed
When installing the 3340 computer, IBM specialists assembled
thought about the question: 'Is it possible to protect
to clean the wheels from dust? After all, in this case
will be possible without the risk of losing data
due to failures, increase the recording density and
disk rotation speed, thereby increasing
the capacity and speed of the storage system
lack of information!'. The result was
sealed bag of two30 discs each
MB each - to achieve such a capacity dis-
without increasing its size and using
old technology was impossible. Numbers
30/30 reminded users of the caliber
Winchester double-barreled shotgun, popular in the USA
30/30", hence the name of the technology
gii. New drives in all respects
superior to magnetic drums, and to tapes
inferior only in unit cost of in-
formations. As a result, after some
time hard drives became mainstream
external memory devices (magnetic
tapes continue to be used only
for long-term storage of large quantities
information quality). After a while
technological progress and falling costs
HDD made it possible to abandon replaceability
disks and since then the hard drive device
did not change: several disks mounted
on one axis, electric motor and read-
records/records enclosed in a sealed
body All of the above applies to
"real computers" - mini-computers, universal
universal supercomputer. As for would-
commercial and personal computers, then because
initially many of them were supplied without
floppy disk drives,
not to mention hard drives. The reason is-
was simple: PCs were considered simply
like a toy. Magnetic disk drives
they were expensive, and there was a great need for
you weren't in them - why?to the then-
for the home user speed and capacity
Winchester? The IBM PC was also built
ability to work with household cassette tape
tape recorder, but the hard drive does not support
was neither the first versions of BIOS nor
MS-DOS. However, such a tactic was not found
special support from users and already
The IBM PC XT began to roll off the assembly line with
built-in hard drive. It happened in
1983 and for that time there was a sign
a major step forward, although the parameters of this
devices are now capable of causing only
tears of tenderness: usable volume 10 MB
(nowadays there are hard drives with useful storage
more than 1 GB), average access time
pa 100 ms (the value of this parameter is currently
hour does not exceed 15 ms, and even then it is sufficient
exactly the old models - for the new ones it is closer
to 5 ms), the actual data transfer rate
about 85 KB/s (as of today
day this speed increased significantly) and
all this in a body that occupies a five-inch
full height compartment. A standard
somewhere the hard drive became a PC accessory
by 1986, when work was only done with bending
with disks has become almost impossible
and new portable ones came in a wide stream
computers equipped with hard drives
(before this their presence was brought to
sacrifice of compactness).An interesting and instructive story. And
more powerful cars today
were once equipped with tape recorders and
dusty floppy disks. Currently
the development of ZX-STRUM is impossible without re-
shared use of hard drives. But
you need to understand that the ZX-STRESTRUM can still
and do without hard drives with useful hardware
with a capacity of 1 GB or more, this is not needed yet
but... Currently, the average user
it will be enough for the body to increase
the speed of working with data will ensure it
more reliable safety and accessibility
without long searches on the shelves, the opportunity
work on the ZX network, and since at this time
ment data on 'sinclair' is calculated
Kbytes, then it’s not worth it at this stage
acquires a hard drive, the capacity of which
designed for five 'WINDOWS 95', seven
'NORTON COMMANDERS', a bunch of 'DOOM's and so on -
what a bunch of 'WING COMMANDERS'. Well kuha-
tit of history! Let's move on to the description of the wines.
Comrade'.
Magazine COMPUNITY-4(8) 1996:
___________________________
HOW THEY ARE STRUCTURED
The modern hard drive represents a co-
fightsealed rectangular iron
box (that’s why in the jargon it
often called a "tin can"). For
There are two connectors for communication with the “outside world”:
an interface is connected to one of them
cable (it is through it that transmission occurs)
information), and connects to another
power cable. Inside there is one or
two electric motors - the first rotates the axis
rigidly fixed to it with metal
disks, and the other (if any) moves
The read/write heads are jammed. Each disk
can be considered divided into concentric
tracks and sectors (actually magnetic
this layer is continuous and such a partition is
exists only at the logical level). B
difference from floppy drives
The hard drive motor is constantly on (except
moments when the hard drive stops at the so-called
"green" computers). Total
number of tracks located on different
disks at equal distances from the axis of rotation
tion is called a cylinder. Typically for
information storage is not used until
horns located at the very edge of the disc
and very close to the center. During production
disk in these areas may appear fi-
physical defects. Inner cylinders
often used for "parking" heads
with the power off - only during this
time they touch the surface of the disk. When
work, thanks to the air flow from theof a package of disks, the head hovers above
its surface at a distance of
mm microns. Unlike floppy, where
the head is always pressed against the carrier, lowered
the heads tilt onto the working surface
could ruin the disk. Also often not used
enjoys the top of the topmost
disk in the package and the lower part of the lowest
him - this is done in order to
reduce the vertical dimensions of the storage
la. For more than twenty years there has been
The magnetic coating has changed -
Previously it was a layer of iron oxide,
mounted on a base in the form of ferrolacquer (as on
magnetic tape and floppy disks), now
it was replaced by a thin layer of cobalt,
dusted onto the disk. Although the latter was not
much more expensive, but the sprayed layer is
much thinner and more uniform, which allows
reduce the gap between the head and the disk and
increase the recording density due to
what parameters can be significantly improved
drive. Disc rotation speed
modern hard drives amount to 4500
rpm, but some models have more
at a higher speed. And in the old Vinces-
terah it was equal to 3600 rpm. On the se-
today there are two ways to position
sioning of heads. In the first models
hard drives used a stepper drive,
the same as in floppy drives: go-
dexteritymoved along the radius of the disk co-
good for the impulses received by the engine.
Each impulse caused movement with the
of the cooking cylinder onto the adjacent one. Later for
reducing head movement time
began to translate immediately to the desired number
tracks. Nowadays drives with stepping motors
teleme still exist and quite widely
are common, but all new models
equipped with a linear electromagnetic drive
house, more profitable in terms of time to reach
stupid. In such drives the head block
moves by an electromagnet approximately
just like the pickup head in a patho-
no. In order for the block to fall exactly on
cylinder (in this case it can easily be
move to any place) use special
cial servo signals recorded on
disc when it was manufactured. In some
models use a "dedicated entry"
servo signals" - one of the surfaces and
one of the heads in the block only works with
servo pulses recorded on the same
tracks as well as data. Widely uses-
There is also a “built-in servo signal recording”
fishing": on each track of one surface
each disk is allocated an area containing
saving servo information. The first way to pose
allows you to achieve greater speed of positivity
vania, but the second one is more reliable. At linear
drive there is another advantage
compared tostepper - when switching off
power supply heads are sent to the allocated
for them the area is automatic. To achieve
the occurrence of a similar effect in models with stepping
you have to use
special utilities. How does information
mation is written to the disk physically -
as a rule, the secret of the manufacturer: su-
There are quite a lot of methods. Stan-
ARLL coding is now considered standard.
WHAT ARE THERE ARE WINCHESTERS?
Hard drives can be internal or external
and bus. Internal hard drives cost
now in every PC-compatible computer
tere. And external and bus hard drives are used
used less often. Bus hard drives are used
mainly used in laptop computers
terah and their price is too high to
have them at home. External hard drives
divided into SCSI devices (Small
Computer Systems Interface) and devices,
connected to the parallel port. External
SCSI class hard drives are no different
expect from their “inner” brothers,
except that they are more expensive due to the need
you have your own body and source
nutrition.TYPES OF INTERFACES
Today in the "Winchester world" state
Three interfaces are available: IDE, SCSI and
IPI. About interfaces such as ST406/512,
ESDI and SMD can be forgotten as if they cannot withstand
who competed with the winners.
Devices with an IPI interface are used
in powerful universal machines, minicomputers
(strange, but this is the name of the most powerful
cars, so don't think about what we're talking about
is about "Microshas") and older models of ra-
barrel stations due to their high cost. Niche
IDE and its modifications, EIDE - personal
personal computers, and more recently
younger models of workstations. As for-
SCSI is available, then its various variants are
truth are omnipresent - they are found both in
both cheap and expensive computer models
Terov. What interface do you prefer?
more detailed? It depends on what for. For home
Today in the "Winchester world" state
Three interfaces are available: IDE, SCSI and
IPI. About interfaces such as ST406/512,
ESDI and SMD can be forgotten as if they cannot withstand
who competed with the winners.
Devices with an IPI interface are used
in powerful universal machines, minicomputers
(strange, but this is the name of the most powerful
cars, so don't think about what we're talking about
is about "Microshas") and older models of ra-
barrel stations because of themhigh prices. Niche
IDE and its modifications, EIDE - personal
personal computers, and more recently
younger models of workstations. As for-
SCSI is available, then its various variants are
truth are omnipresent - they are found both in
both cheap and expensive computer models
Terov. What interface do you prefer?
more detailed? It depends on what for. For home
EDIE computer will be sufficient - it
fully compatible with older IDE-vin
Chesters. SCSI interfaces are used
with a large number of external devices
(up to 15), it costs more than EIDE and IDE.
RT: Well, this all concerns IBM, but for
ZX-STRUM's most acceptable is -
IDE, since this type of interfaces you
went out of use on IBM and is distinguished by
low price. Over the connection problem
hard drives for SPESSY are now working in
mainly three companies: SLOT Co., SCORPION and
NEMO. And as we know, they have already achieved
certain results. So wait
There's very little left.
Well, now a little about the biggest one
problem of hard drive owners - about the virus
sah. This is a dangerous thing. She is comparable
only with a headache. Viruses can be
find and destroy using antivirus software
programs, but usually theseantivirus
programs are usually written after a fresh
memories of disappeared without a trace
valuable data and therefore viruses are still
they will do their job. Well, as for
other problems - write to us and we will discuss them
on the pages of our magazine. Thank you for your attention.
Goodbye!
Share your thoughts about the article