RS64 disk drive
From Computer History Wiki
RS64 | |
Manufacturer: | Digital Equipment Corporation |
---|---|
Drive Controller(s): | RC11 (UNIBUS) |
Capacity: | 128KB |
Transfer Rate: | 125KB/sec (60 Hz), 100KB/sec (50 Hz) |
Average Access Time: | 16.9msec (60Hz), 20.3msec (50Hz) |
Revolutions per Minute: | ~1800 (60Hz), ~1400 (50Hz) |
Media: | 10" diameter nickel-cobalt plated surface with proprietary protective coating |
Total Surfaces: | 1 |
Tracks per Surface: | 32 |
Sectors per Track: | 64 |
Words per Sector: | 32 |
Density: | 1700 bpi (maximum) |
Recording Method: | NRZI |
Physical Size: | 10" (high), 19" (W, D) |
Weight: | 64 lbs |
Power Consumption: | 6A (starting), 2.2A (operating) |
The RS64 is a fixed-platter fixed-head disk drive used on PDP-8's and early PDP-11s. It could store up to 128KB of data in 64 byte blocks. It used 32 fixed read/write heads for data, and 6 heads to read timing/address tracks (in two duplicated sets of 3, for reliability; switch-over from one set to another was manual).
A special device had to be used to write the timing/address tracks. It had the ability to write-protect tracks 0-N ('N' set in switches).