RM02/03 disk drive
|Manufacturer:||Digital Equipment Corporation|
|Drive Controller(s):|| RH10 (PDP-10)|
|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)|
|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|
|Physical Size:||33" W x 39" H x ??" L|
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.