RF35
| RF35 | |
| Manufacturer: | Digital Equipment Corporation |
|---|---|
| Drive Controller(s): | all DSSI Controllers |
| Capacity: | 852 Mbytes (formatted) |
| Transfer Rate: | 4.0 Mbytes/sec |
| Average Access Time: | 15.1 msec |
| Average Seek Time: | 9.5 msec |
| Start Time: | < 30 sec |
| Stop Time: | < 15 sec |
| Physical Size: | 3.5" half height |
The RF35 is a DSSI hard drive produced by Digital Equipment Corporation from about 1991. This is called an 'Integrated Storage Element' (ISE), which combines the Head-disk assemblies (HDA) and a controller with MSCP server. The MSCP server allows the disk to queue I/O requests from multiple hosts at a time. One of the use cases for this feature is to provide storage to a VAXcluster made of small systems like the MicroVAX.
The drive uses a 50-pin DSSI interface and a 5-pin Molex power connector, providing access to 852 MB of storage. There are 7 platters, each with 2 heads, for a total of 14 data surfaces and ~60MB per surface. The disk geometry is 14 tracks, 2,086 cylinders, 58 sectors per track (including 1 replacement sector).
The disk controller contains a MC680x0 microprocessor, RAM, and NVRAM. A number of diagnostic and utility programs are available to the controller. At startup, there is a POST test and diagnostics continue executing periodically while the disk runs. In addition to error codes visible via the diagnostic programs, the disk has an amber-colored Fault LED.
The RF31T is a lower-capacity version of the RF35, but with an improved seek rate.
External Links
- RF Series Integrated Storage Element User Guide (EK-RF72D-UG-007)
- RF Series Integrated Storage Element User Guide (EK-RF72D-UG-008)
- RF35 in the collection of the Computer History Museum
