Difference between revisions of "RS03/04 disk drive"
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{{Infobox Disk drive | {{Infobox Disk drive | ||
| name = RS03/RS04 | | name = RS03/RS04 | ||
| − | | manufacturer = [[Digital Equipment Corporation]] | + | | manufacturer = [[Digital Equipment Corporation|DEC]] |
| rpm = 3600 (60Hz) | | rpm = 3600 (60Hz) | ||
| average access time = 8.5 msec (60Hz), 10.2 msec (50Hz) | | average access time = 8.5 msec (60Hz), 10.2 msec (50Hz) | ||
| Line 11: | Line 11: | ||
| media = 16" diameter nickel-cobalt plated surface | | media = 16" diameter nickel-cobalt plated surface | ||
| transfer rate = 2 μsec/byte (RS03), μ1 sec/byte (RS04) | | transfer rate = 2 μsec/byte (RS03), μ1 sec/byte (RS04) | ||
| − | | density = xxx bpi (maximum) | + | <!-- | density = xxx bpi (maximum) --> |
| recording method = [[Modified Frequency Modulation|MFM]] | | recording method = [[Modified Frequency Modulation|MFM]] | ||
| physical size = 15-3/4" (high), 19" (width), 26-1/4" (depth) | | physical size = 15-3/4" (high), 19" (width), 26-1/4" (depth) | ||
| Line 29: | Line 29: | ||
The '''RS03''' and '''RS04 disk drives''' were [[MASSBUS]] fixed-platter [[fixed-head disk]] [[drive]]s. Their basic format was 18-[[bit]] [[word]]s (for use in [[PDP-10]] and [[PDP-15]] machines), but they could be used in [[PDP-11]]s, where they simply ignored two bits. | The '''RS03''' and '''RS04 disk drives''' were [[MASSBUS]] fixed-platter [[fixed-head disk]] [[drive]]s. Their basic format was 18-[[bit]] [[word]]s (for use in [[PDP-10]] and [[PDP-15]] machines), but they could be used in [[PDP-11]]s, where they simply ignored two bits. | ||
| − | They attach to any MASSBUS controller, e.g. [[RH11 MASSBUS controller|RH11]] ([[UNIBUS]]), [[RH70 MASSBUS controller|RH70]], or [[RH10 MASSBUS controller|RH10]]. Up to 8 devices total can be attached to any MASSBUS controller. | + | They attach to any MASSBUS controller, e.g. [[RH11 MASSBUS controller|RH11]] ([[UNIBUS]]), [[RH70 MASSBUS controller|RH70]], or [[RH10 MASSBUS controller|RH10]]. Up to 8 devices total can be attached to any MASSBUS controller. Data was protected by a 16-bit [[cyclic redundancy check|CRC]] per sector. |
The RS04 doubled the capacity (and bit rate) of the RS03 by recording on both sides of the [[platter]]; alternate bits in each word came from alternate sides. | The RS04 doubled the capacity (and bit rate) of the RS03 by recording on both sides of the [[platter]]; alternate bits in each word came from alternate sides. | ||
| Line 35: | Line 35: | ||
They could store up to 512KB of data in 128 byte blocks (RS03), or 1024KB of data in 256 byte blocks (RS04). They used 64 fixed read/write [[head]]s per side for data (8 spares were provided), and 2 heads to read timing/address [[track]]s (a main and a backup). | They could store up to 512KB of data in 128 byte blocks (RS03), or 1024KB of data in 256 byte blocks (RS04). They used 64 fixed read/write [[head]]s per side for data (8 spares were provided), and 2 heads to read timing/address [[track]]s (a main and a backup). | ||
| − | The second timing track did not provide reliability/redundancy; the two tracks were not recorded synchonously. (This seeming oversight may be explained from DEC's apparent intent that this device be used for [[swap|swapping]], where being unable to retrieve data would not be an issue. Indeed, the RS0x [[diagnostic]]s scribbled over the disk - which caused an issue the first time they were run at Bell Labs, where [[UNIX]] used one as a root drive!) Switch-over from one to another was manual, by inverting a connector. | + | The second timing track did not provide reliability/redundancy; the two tracks were not recorded synchonously. (This seeming oversight may be explained from DEC's apparent intent that this device be used for [[swap|swapping]], where being unable to retrieve data would not be an issue. Indeed, the RS0x [[diagnostic]]s scribbled over the disk - which caused an issue the first time they were run at Bell Labs, where [[UNIX]] used one as a root drive!) Switch-over from one timing track to another was manual, by inverting a connector. |
The drive had the ability to write-protect tracks 0-N ('N' set in switches). | The drive had the ability to write-protect tracks 0-N ('N' set in switches). | ||
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{{semi-stub}} | {{semi-stub}} | ||
| − | [[Category: MASSBUS | + | ==External links== |
| − | [[Category: DEC | + | |
| + | * [http://www.bitsavers.org/pdf/dec/disc/rjs03_rjs04/DEC-11-HRJSA-B-D_RJS04_RJS03_fixed-head_disk_system_maintenance_manual_Aug1974.pdf RJS04/RJS03 fixed-head disk system maintenance manual] (DEC-11-HRJSA-B-D) | ||
| + | * [http://www.bitsavers.org/www.computer.museum.uq.edu.au/pdf/DEC-00-HRS3A-A-D%20RS03%20DECdisk%20Service%20Manual.pdf RS03 DECdisk Service Manual] (DEC-00-HRS3A-A-D) | ||
| + | * [http://www.bitsavers.org/www.computer.museum.uq.edu.au/pdf/DEC-00-HRS4A-A-D%20RS04%20DECdisk%20Service%20Manual.pdf RS04 DECdisk Service Manual] (DEC-00-HRS4A-A-D) | ||
| + | * [http://www.bitsavers.org/pdf/dec/disc/rs04/RS04_Engineering_Drawings_Jul73.pdf RS04 Engineering Drawings] | ||
| + | |||
| + | [[Category: MASSBUS Disk Drives]] | ||
| + | [[Category: DEC Fixed-head Disks]] | ||
Latest revision as of 17:37, 14 August 2023
| RS03/RS04 | |
| Manufacturer: | DEC |
|---|---|
| Drive Controller(s): | RH11 (UNIBUS), RH70, RH10 |
| Capacity: | 512KB (RS03), 1024KB (RS04) |
| Transfer Rate: | 2 μsec/byte (RS03), μ1 sec/byte (RS04) |
| Average Access Time: | 8.5 msec (60Hz), 10.2 msec (50Hz) |
| Revolutions per Minute: | 3600 (60Hz) |
| Media: | 16" diameter nickel-cobalt plated surface |
| Total Surfaces: | 1 (RS03), 2 (RS04) |
| Tracks per Surface: | 64 (plus 8 spares) |
| Sectors per Track: | 64 |
| Words per Sector: | 128 bytes (RS03), 256 bytes (RS04) |
| Recording Method: | MFM |
| Physical Size: | 15-3/4" (high), 19" (width), 26-1/4" (depth) |
| Weight: | 120 lbs |
| Power Consumption: | 13A (starting), 6A (operating) |
The RS03 and RS04 disk drives were MASSBUS fixed-platter fixed-head disk drives. Their basic format was 18-bit words (for use in PDP-10 and PDP-15 machines), but they could be used in PDP-11s, where they simply ignored two bits.
They attach to any MASSBUS controller, e.g. RH11 (UNIBUS), RH70, or RH10. Up to 8 devices total can be attached to any MASSBUS controller. Data was protected by a 16-bit CRC per sector.
The RS04 doubled the capacity (and bit rate) of the RS03 by recording on both sides of the platter; alternate bits in each word came from alternate sides.
They could store up to 512KB of data in 128 byte blocks (RS03), or 1024KB of data in 256 byte blocks (RS04). They used 64 fixed read/write heads per side for data (8 spares were provided), and 2 heads to read timing/address tracks (a main and a backup).
The second timing track did not provide reliability/redundancy; the two tracks were not recorded synchonously. (This seeming oversight may be explained from DEC's apparent intent that this device be used for swapping, where being unable to retrieve data would not be an issue. Indeed, the RS0x diagnostics scribbled over the disk - which caused an issue the first time they were run at Bell Labs, where UNIX used one as a root drive!) Switch-over from one timing track to another was manual, by inverting a connector.
The drive had the ability to write-protect tracks 0-N ('N' set in switches).
External links
- RJS04/RJS03 fixed-head disk system maintenance manual (DEC-11-HRJSA-B-D)
- RS03 DECdisk Service Manual (DEC-00-HRS3A-A-D)
- RS04 DECdisk Service Manual (DEC-00-HRS4A-A-D)
- RS04 Engineering Drawings
