Category : HD Utilities
Archive   : MICROPOL.ZIP
Filename : 1550SPEC.TXT

MICROPOLIS 1558 DISK DRIVE
SPECIFICATIONS

Model Number
Unformatted Capacity: 1558-15

Total Mbytes ---------------- 382.3 --------------------
Disk Platters -------------------- 8 --------------------
Read/Write Heads ------------------- 15 --------------------
Cylinders ----------------- 1224 --------------------
Bytes per track --------------- 20,832 --------------------

Formatted Capacity (typical)

Total Mbytes ---------------- 338.1 --------------------
Bytes per Sector ------------------ 512 --------------------
Sectors per Track ------------------- 36 --------------------

PC Drive Types

If you are using third-party installation software or an on-
board BIOS on the controller, follow the instructions included
with the software or controller. Otherwise, examine the entries
in your system drive table and find the type that most resembles
the head and cylinder parameters of the drive without exceeding
these parameters.

Performance Specifications

Seek Time (including settling time) Track-to-Track 4 msec
Average 18 msec
Maximum 40 msec
Average Rotational Latency 8.33 msec
Rotational Speed 3600 rpm +/- 0.5%
Data Transfer Rate 10 Mbits/sec
MTBF 150,000 hours
Positioner Fully balanced rotary voice coil
Parking Automatic park and lock

General Functional Specifications

Interface ESDI
Sectoring (see W1 description, below) Hard or Soft
Write Precompensation Start Cylinder 1224*
Reduced Write Current Start Cylinder 1224*
Landing Zone 1224
Mounting Plane Any orientation

* These are effectively turned off by specifying a non-existent
cylinder. Some systems accomplish this by using a value of "-1"

Power Requirements

+12V +/-5% 2.0A avg
(4.25A max during start-up)
+5V +/-5% 2.0A avg
Power dissipation, typical 32 Watts

Drive Addressing and Interface Termination

NOT
USED J2 J1 J3
____ ________ ___________________ _ _________
| | | |1| | |1| | | POWER |
| |_| |____| |_| |_________|
| |
| R |
| N |
| 1 |
| |
| W1 |
| W2 |
| W3 |
| (Component Side) W4 |
| W5 _|
| DA1 |
| DA2 |_
| DA3 |
| |

RN1 Interface Terminator
The Interface Terminator factory installed at RN1 will provide
proper termination for the interface lines. When daisy-chaining
multiple drives, leave the terminator installed only in the last
physical drive on the daisy chain; remove the terminator from
each of the other drives. In most PC/AT installations, the C:
drive is actually at the end of the cable and should retain the
terminator.

DA1, DA2, DA3 Drive Address Jumpers
The drive address jumpers are identified as DA1, DA2 and DA3.
Address selection is binary, as shown in the table below. The
ESDI controller's documentation will specify the drive address
to use.

Drive Select Jumpers
Address DA3 DA2 DA1
------- --- --- ---
1 out out in
2 out in out
3 out in in
4 in out out
5 in out in
6 in in out
7 in in in

"Drive address 0" (no jumper at DA1, DA2 or DA3) is a "deselect"
(i.e., no drive selected). Drives are factory configured as Drive
Address 1. For many multiple drive installations, each drive must
have a unique address. An exception is that for every drive in
a PC/AT installation, verify that the only Drive Address is at
DA2; move the jumper if necessary (the special twisted interface
cable that is generally used takes care of assigning a unique
address to each drive). PC/AT controllers can typically support
a maximum of two drives.

W5 Selects the Spindle Control Option.
If W5 is installed, the drive waits for a Start Spindle command
(after power is applied) to start the spindle motor. If W5 is
not installed (the factory default configuration), the drive will
automatically start the spindle motor at power-on. W5 is not
installed for PC/AT applications.

W1 Selects the Sectoring Mode.
If W1 is installed, the drive operates in the soft-sectored mode.
If W1 is not installed (the factory default configuration), the
drive operates in the hard-sector mode. W1 is not installed for
most PC/AT in applications.

W2, W3, W4 Sector Size Option
The number of bytes per sector may be specified using the Set
Bytes Per Sector command or by selecting a default sector
configuration with jumpers W2, W3, and W4 as follows:

Jumpers Sectors Bytes/Sector
W4 W3 W2 Per Track Formatted Unformatted
--- --- --- --------- --------- -----------
out out out 35 512 595
-------------------------------------------------------------
| * out out in 36 512 578 |
-------------------------------------------------------------
out in out 19 1024 1096
out in in 9 2048 2314
in out out 5 4096 4166
in out in 32 512 651
in in out 64 256 325
in in in 1 20,832 20,832

* This is the default (factory installed) configuration and is
recommended for PC/AT applications