P R A I R I E 2 4 2 A T PRAIRIETEK
NO MORE PRODUCED Native| Translation
------+-----+-----+-----
Form 2.5"/SLIMLINE Cylinders 615| | |
Capacity form/unform 42/ MB Heads 4| | |
Seek time / track 23.0/ 8.0 ms Sector/track 34| | |
Controller IDE / AT Precompensation
Cache/Buffer KB Landing Zone
Data transfer rate 1.250 MB/S int Bytes/Sector 512
5.000 MB/S ext
Recording method RLL 2/7 operating | non-operating
-------------+--------------
Supply voltage 5 V Temperature *C 5 55 | -40 70
Power: sleep W Humidity % | 10 90
standby 0.1 W Altitude km -0.305 3.048| 12.192
idle 1.1 W Shock g 5 | 100
seek W Rotation RPM 3307
read/write 2.5 W Acoustic dBA
spin-up 3.5 W ECC Bit YES
MTBF h 100000
Warranty Month
Lift/Lock/Park YES Certificates CSA,IEC435,UL1950,VDE
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L A Y O U T
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PRAIRIE. PRAIRIE 242 PRODUCT MANUAL 70031C REV. X2, 19/2/1991
+-------------------------------------------------------+
| +-----++-----++-----+ +------+ |
| | || || | | | |
| | || || | | | |XX
| | || || | | | |XX
| +-----++-----++-----+ | | |XX
| +------+ |XX
| +---------+ |XX
| | | |XX
| | | |XX
| | | |XX
| | | |XX
| +---------+ +------+ |XX
| +-+ | | |XX
| +-------+ |:|E1 | | |
| | | +-+ | | |
| +-------+ +------+ |
+-------------------------------------------------------+
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J U M P E R S
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PRAIRIE. PRAIRIE 242 PRODUCT MANUAL REV. X2 70031C 19/2/1991
Jumper Setting
==============
Customer Options
----------------
The host interface on the 242 can be set to run on either an AT or XT
compatible system. The polarity of Pin 44 on the interface will de-
termine XT or AT operation (+AT, -XT). When Pin 44 is grounded, the
signal will enable the XT Mode.
In AT mode, the 242 can operate as a single drive or in a dual drive
(master/slave) configuration. The jumper trace E1 is shorted from the
factory indicating a single drive or the master. In dual drive
configuration, the E1 trace must be cut to indicate the second drive
or slave.
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I N S T A L L
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PRAIRIE. PRAIRIE 242 PRODUCT MANUAL REV. X2 70031C 19/2/1991
Notes On Installation
=====================
Mounting Configurations
-----------------------
The features which allow greater shock and vibration tolerance
include the dynamically loaded heads, a fully balanced rotary
actuator, and the low overall mass and weight of the drive and
moving masses.
Adequate ventilation must be provided to the drive to ensure reliable
operation over the specified operating temperature range.
The drive may be mounted in any attitude. It can be mounted either
from the side or the bottom using four M2X.4 screws.
The drive is available with two different connector systems.
The connector 2A is a Dupont Mini Tek II, 2 x 2mm (Double Row) header
consisting of 50 positions. Th eHost Interface and power are accessed
through P1 to Pin 44. The recommended mating connector is Dupont part
number 86991-144 or equivalent.
The connector 2B is a KEL 8830B Series Plug with 0.05 inch spacing
(Double Row) consisting of 50 positions. The Host Interface and
power are accessed through P1 to Pin 44. The recommended mating
connectors are KEL 8800 Series Receptacles (50 pin).
Physical Decription
-------------------
The Model 242 Host Interface can be directly connected to the Host or
can accommodate cable connection with a maximum length of 2 feet
(610mm).
Connector
---------
On the DuPont header, the separate 4 pins are for factory test pur-
poses and are not associated with the Host Interface. These pins
should be left disconnected.
On the KEL Plug, Pin 47 through 50 are for factory test purposes and
these pins should be left disconnected. Additionally, Pin 45 should
be connected to +5V return and Pin 46 should be connected to +5V
supply.
Electrical Description
----------------------
All signal levels are TTL compatible. A logic "1" is > 2.0 volts. A
logic "0" is from 0.00 volts to 0.70 volts.
The interface between the drive adapter and the drive is called the
Host Interface.
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F E A T U R E S
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PRAIRIE. PRAIRIE 242 PRODUCT MANUAL 70031C REV. X2 19/02/1991
Key Features
------------
Unique ramp loading mechanism for loading and unloading the disk
heads during power-downs and periods of inactivity.
User invoked low power modes and power-downs for power sensitive
applications.
High performance rotary voice coil actuator with embedded servo
system.
On-board controller for direct connection to a 44-pin interface.
Microprocessor - controlled diagnostic routines that are
automatically performed at power up.
Internal air filtration system.
Automatic error detection and correction.
Functional Description
----------------------
The Model 242 disk drive contains all the necessary mechanical and
electronic components to interpret control signals, properly position
the recording heads, read and write data, and maintain a contaminant
free environment for the disks and recording heads.
Read/Write and Control Electronics
----------------------------------
The Model 242 has an integrated circuit attached to the flexible
circuit connected to the actuator arm and read/write heads to provide
one of four head selections, read preamplification, and write drive
circuitry.
The microprocessor controlled circuit board provides the remaining
electronic functions including:
- Read/Write Circuitry
- Rotary Actuator Control
- Interface Control
- Power Management
- Spin Speed Control
- Automatic Head Unloading
Error Correction
----------------
The Model 242 performs internal error correction through the use of
a polynomial capable of correcting one error burst with a maximum of
11 bits per 512 byte block.
Diagnostic Routines
-------------------
Upon power up the microprocessor circuitry of the Model 242 performs
diagnostics. If an error is detected the drive will not come ready.
Spin-Up/Down Operations
-----------------------
When power is applied to the drive, it will perform its diagnostics
and come ready. To conserve power, it will accept commands, but will
not spin up until it receives a command requiring a disk access (such
as a Read, Write, Seek, Recal, etc.).
When spinning up for the first time after application power, it will
spin up and do a servo calibration which requires a total time of 5
seconds (typically).
