Hard Drive: EPSON: HMD-726A 20MB 3.5"/HH SCSI1 SE
H M D - 7 2 6 A EPSON
NO MORE PRODUCED Native| Translation
------+-----+-----+-----
Form 3.5"/HH Cylinders 615| | |
Capacity form/unform 20/ MB Heads 4| | |
Seek time / track 80.0/18.0 ms Sector/track 33| | |
Controller SCSI1 SINGLE-ENDED Precompensation
Cache/Buffer KB Landing Zone
Data transfer rate 0.625 MB/S int Bytes/Sector 256
MB/S ext
Recording method RLL 2/7 operating | non-operating
-------------+--------------
Supply voltage 5/12 V Temperature *C 5 50 | -40 65
Power: sleep W Humidity % 8 80 | 8 85
standby W Altitude km 3.000| 10.000
idle 10.2 W Shock g 4 | 40
seek W Rotation RPM 3323
read/write W Acoustic dBA 50
spin-up W ECC Bit 32,WITH 11BIT BURST COR
MTBF h 20000
Warranty Month
Lift/Lock/Park NO Certificates
Layout
EPSON HMD-726A PRODUCT MANUAL MK3700-S 06-86
+---------------------------------------------------------+ | |XX J2 | |XX Power | | | |XX I | |XX N | |XX T | |XX E | |XX R | |XX F | |XX A | |XX C | |XX E | SS2 SS1 |XX | 8--------0 8--------0 |XX J1 +--------------------------------+--------+---+--------+--+
Jumpers
EPSON HMD-726A PRODUCT MANUAL MK3700-S 06-86
Jumper Setting
==============
SS1 Termination
----------------
ALL CLOSED Activate line termination
SS2 Drive Select
-----------------
PINS
| 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7
---+------+------+------+------+------+------+------+-----
S 0 |CLOSED|OPEN |OPEN |OPEN |OPEN |OPEN |OPEN |OPEN
C 1 |OPEN |CLOSED|OPEN |OPEN |OPEN |OPEN |OPEN |OPEN
S 2 |OPEN |OPEN |CLOSED|OPEN |OPEN |OPEN |OPEN |OPEN
I 3 |OPEN |OPEN |OPEN |CLOSED|OPEN |OPEN |OPEN |OPEN
4 |OPEN |OPEN |OPEN |OPEN |CLOSED|OPEN |OPEN |OPEN
I 5 |OPEN |OPEN |OPEN |OPEN |OPEN |CLOSED|OPEN |OPEN
D 6 |OPEN |OPEN |OPEN |OPEN |OPEN |OPEN |CLOSED|OPEN
7 |OPEN |OPEN |OPEN |OPEN |OPEN |OPEN |OPEN |CLOSED
Install
ESPON HMD-726A PRODUCT MANUAL MK3700-S 06-86
Notes on installation
=====================
Installation direction
----------------------
horizontally vertically
+-----------------+ +--+ +--+
| | | +-----+ +-----+ |
| | | | | | | |
+-+-----------------+-+ | | | | | |
+---------------------+ | | | | | |
| | | | | |
x x | | | | | |
+------x------x-------+ | +-----+ +-----+ |
+-+------x--x-------+-+ +--+ +--+
| xx |
| x x |
+---x--------x----+
x x
Recommended orientation is vertical on either long side or
horizontal with the PCB down or vertical with front bezel up or down.
The prohibited orientation is horizontal with the PCB up.
Mounting screws
---------------
There are 8 mounting tapped holes on the mounting frame. The drive
will be mounted using UNC *6-32 or M-3 or M-4 screws (both types are
available), with 3.5mm (0.14 inches) maximum penetration.
Mounting Clearance
------------------
The EPSON HMD-726A is designed to withstand shocks and vibrations at
greater levels. However, to take full advantage of the shock
absorbers, it is necessary to provide a clearance of 2.5mm or 0.1
inch on all sides of the drive. This clearance allows for movement of
the drive during accelaration and also free air flow for ventilation.
Electrical Interface
--------------------
The electrical interface consists of two parts, each of which is
physically separated.
(1) Interface Signals (J1/P1)
(2) DC Power Input (J2/P2)
All Interface signal lines are digital (terminated open collector TTL) and provide signals either to or from the drive via a 50 pin connector J1/P1. Connector J2/P2 provides the drive with DC powers (+12V and +5V).
Flat Cable or Twisted Pair, max 20 Feet True or Low Level: 0.0 VDC to 0.4 VDC, 1 = -48 mA (max) False or High Level: 2.5 VDC to 5.25 VDC, 1 = +250 A (open collector)
J1/P1 Connector
---------------
Connection to J1 is through a 50-pin flat ribbon connector. The
recommended mating connector is the AMP P/N 88551-5 cable connector.
J2/P2 Connector
---------------
DC power connector J2 is a 4-pin AMP Mate-N-Lok connector, mounted on
the Pronted Circuit Board. The recommended mating connector for P2 is
AMP P/N 1-480424-0 utilizing AMP pins P/N 350078-4.
+------------+ pin 1 +12 VDC
| 4 3 2 1 | pin 2 +12 Volts Ground Return
+------------+ pin 3 + 5 Volts Ground Return
pin 4 + 5 VDC
Installation
------------
Multiple-Drive Systems
----------------------
Up to seven drives can be connected to a single host.
Drive #0
+---HOST------+ +--------------+--+
| +--+-SCSI-BUS-----+ J1 |OP|
| | | +------+ J2 +--+
| | | | +-----------------+
+-------------+ | | Drive #2
| | +--------------+--+
o-------+------+ J1 |OP|
| o------+ J2 +--+
| | +-----------------+
| |
| |
| | Drive #7
| | +--------------+--+
+-------+------+ J1 |CL|
o------+ J2 +--+
---DC-VOLTAGE------+ +-----------------+
CL = SHUNT BLOCK SS1 ALL SHORTED
OP = SHUNT BLOCK SS1 ALL OPEN
Features
EPSON HMD-726A PRODUCT MANUAL MK3700-S 06-86
Introduction
------------
The EPSON HMD-726A is a 20-Megabyte intelligent 3-5 nch half height
hard disc drive which communicates with a host computer via the small
computer system Interface (SCSI).
Feature:
1. The drive and controller electronics within the standard 3.5" form
factor.
2. The highly efficient rotary actuator and drive circuits achieve
low power consumption.
3. Thermal off-track compensation system achives 910 tpi with
excellent repeatability.
4. Hardware 32 bit ECC polynominal with up to 11 bit burst
correction.
5. Reliability is enhanced by selected with 20,000 hours MTBF.
Seek Time
---------
+----------------------------------+--------+
|Track-to-Track msec. typ. | 18 |
+----------------------------------+--------+
|Average msec. typ. | 80 |
| msec. max. | 150 |
+----------------------------------+--------+
|Latency msec. avg. | 8.5 |
+----------------------------------+--------+
Media Defect
------------
Maximum Defects Per Surface 10
Maximum Defects Per Drive 32
Cylinder Zero certified Defect Free
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