Difference between revisions of "RM02/03 disk drive"

From Computer History Wiki
Jump to: navigation, search
(Combine into one page)
(Add more info)
Line 1: Line 1:
The '''RM02''' and '''RM03''' were 67MB [[MASSBUS]] [[disk]] [[pack]] [[drive]]s. The RM02 had 806 KB/s transfers, 42.5 ms average access time, 6 ms [[track]]-to-track [[seek]] time, 2400 RPM; the RM03 had 1200 KB/s transfer, 38.3 ms average access time, 6 ms track-to-track seek time, 3600 RPM.
+
{{Infobox Disk drive
+
| name = RM02/RM03
{{stub}}
+
| manufacturer = [[Digital Equipment Corporation]]
 +
| controller = [[RH10 MASSBUS controller|RH10]] ([[PDP-10]])<br>[[RH20 MASSBUS controller|RH20]] ([[KL10]])<br>[[RH11 MASSBUS controller|RH11]] ([[UNIBUS]])<br>[[RH70 MASSBUS controller|RH70]] ([[PDP-11/70]])<br>[[RH780 MASSBUS controller|RH780]] ([[VAX-11/780]])<br>[[RH750 MASSBUS controller|RH750]] ([[VAX-11/750]])
 +
| capacity = 67 Mbytes
 +
| transfer rate = 2.48 μsec/word (RM02/16-bit)<br>2.79 μsec/word (RM02/18-bit)<br>1.65 μsec/word (RM03/16-bit)<br>1.86 μsec/word (RM03/18-bit)<br>
 +
| average access time = 42.5 msec (RM02)<br>38.3 msec (RM03)
 +
| rpm = 2400 (RM02)<br>3600 (RM03)
 +
| revolution time = 25.9 msec (RM02)<br>17.3 msec (RM03)
 +
| one track seek = 6 msec
 +
| average seek = 30 msec
 +
| maximum seek = 55 msec
 +
| surfaces = 6 (5 data, 1 servo)
 +
| tracks = 823<!-- (nominally 400 plus 6 spares; many systems used all 406, as reliability was high) -->
 +
| sectors = 30 (18-bit words)<br>32 (16-bit words)
 +
| words per sector = 256
 +
<!-- | tracks per inch = 100 -->
 +
<!-- | density = 2200 bpi (maximum) -->
 +
| recording method = [[Modified Frequency Modulation|MFM]]
 +
| physical size = 33" W x 39" H x ??" L
 +
| weight = 430 pounds
 +
<!-- | power consumption = 660 VA per phase (running); 3300 VA per phase(starting) -->
 +
}}
 +
 
 +
The '''RM02''' and '''RM03''' were [[MASSBUS]] multi-[[platter]] large  moving-[[head]] [[disk]] [[pack]] [[drive]]s. They were effectively identical, except that the RM03 rotated faster (3600 RPM, versus 2400 RPM for the RM02). Both supported both 15-bit and 18-bit [[word]]s; user data is protected by a 32-bit [[error-correcting code|ECC]] per [[sector]].
 +
 
 +
RM0x drives are dual-ported, allowing any drive to be attached to two different controllers. Generally a maximum of 8 drives were supported per [[device controller]].
 +
 
 +
The RM02 provided 806 KB/s transfers; the RM03 had 1200 KB/s transfer.
 +
 
 +
{{semi-stub}}
  
 
[[Category: MASSBUS Devices]]
 
[[Category: MASSBUS Devices]]
 
[[Category: DEC Disk Drives]]
 
[[Category: DEC Disk Drives]]

Revision as of 18:57, 3 November 2020



RM02/RM03
Manufacturer: Digital Equipment Corporation
Drive Controller(s): RH10 (PDP-10)
RH20 (KL10)
RH11 (UNIBUS)
RH70 (PDP-11/70)
RH780 (VAX-11/780)
RH750 (VAX-11/750)
Capacity: 67 Mbytes
Transfer Rate: 2.48 μsec/word (RM02/16-bit)
2.79 μsec/word (RM02/18-bit)
1.65 μsec/word (RM03/16-bit)
1.86 μsec/word (RM03/18-bit)
Average Access Time: 42.5 msec (RM02)
38.3 msec (RM03)
Revolutions Per Minute: 2400 (RM02)
3600 (RM03)
1/2 Revolution Time: 25.9 msec (RM02)
17.3 msec (RM03)
One Track Seek Time: 6 msec
Average Seek Time: 30 msec
Maximum Seek Time: 55 msec
Total Surfaces: 6 (5 data, 1 servo)
Tracks Per Surface: 823
Sectors Per Track: 30 (18-bit words)
32 (16-bit words)
Words Per Sector: 256
Recording Method: MFM
Physical Size: 33" W x 39" H x ??" L
Weight: 430 pounds


The RM02 and RM03 were MASSBUS multi-platter large moving-head disk pack drives. They were effectively identical, except that the RM03 rotated faster (3600 RPM, versus 2400 RPM for the RM02). Both supported both 15-bit and 18-bit words; user data is protected by a 32-bit ECC per sector.

RM0x drives are dual-ported, allowing any drive to be attached to two different controllers. Generally a maximum of 8 drives were supported per device controller.

The RM02 provided 806 KB/s transfers; the RM03 had 1200 KB/s transfer.