Difference between revisions of "RM80 Disk Drive"
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| − | [[ | + | {{Infobox Disk drive |
| + | | name = RM80 | ||
| + | | manufacturer = [[Digital Equipment Corporation|DEC]] | ||
| + | | year introduced = October, 1980 | ||
| + | | controller = [[RH11 MASSBUS controller|RH11]], [[RH70 MASSBUS controller|RH70]], [[RH10 MASSBUS controller|RH10]], [[RH20 MASSBUS controller|RH20]], [[RH780 Massbus Adapter|RH780]], [[RH750 Massbus Adapter|RH750]] | ||
| + | | capacity = 124 Mbytes | ||
| + | | transfer rate = 1.2 Mbytes/sec | ||
| + | | average access time = 33.3 msec | ||
| + | | rpm = 3600 | ||
| + | | revolution time = 8.3 msec | ||
| + | | one track seek = 6 msec | ||
| + | | average seek = 25 msec | ||
| + | | maximum seek = 50 msec | ||
| + | | surfaces = 7 data, 1 servo | ||
| + | | number of heads = 14 data,<br>1 servo (read-only) | ||
| + | | tracks = 561 (18-bit word mode)<br>559 (16-bit word mode) | ||
| + | | sectors = 30 (18-bit word mode)<br>31 (useable; 16-bit word mode) | ||
| + | | words per sector = 256 (16-bit word mode) | ||
| + | | tracks per inch = 478 | ||
| + | | density = 6339 (max; inner track) | ||
| + | | recording method = [[Modified Frequency Modulation|MFM]] | ||
| + | | start time = 20 secs (avg);<br>40 secs (max) | ||
| + | | stop time = 9 secs (avg);<br>13 secs (max) | ||
| + | | physical size = 26cm x 44cm x 67cm | ||
| + | | weight = 135 lbs (approx) | ||
| + | | power consumption = 575 watts | ||
| + | }} | ||
| − | + | [[Image:rm80.jpg|thumb|200px|left|RM80]] | |
| + | |||
| + | The '''RM80 Disk Drive''' was a [[MASSBUS]] [[non-removable-media disk]] from [[Digital Equipment Corporation|DEC]]; it held 124 MB. It was apparently the MASSBUS version of the [[R80 Disk Drive]]; it could support either 16- or 18-bit words. It was internally operated by a [[microprocessor]] which used 32-bit burst [[error-correcting code|ECC]] to invisibly repair simple data errors. | ||
| + | |||
| + | It had two heads per surface; not rotationally opposed (to halve maximum access time), but two on each arm; there were thus 1,122 usable tracks on each data surface (in 18-bit word mode; 4 tracks were reserved for maintenance purposes in 16-bit mode). 1 sector per track was reserved for bad block replacement in 16-bit word mode, out of 32 total. | ||
| + | |||
| + | The RM80 can also be connected in a dual-[[hardware port|port]] arrangement, permitting its use by two [[device controller|controllers]]. | ||
==Further reading== | ==Further reading== | ||
| − | RM80 Disk Drive Technical Description Manual (EP-0RM80-TD-001) - not available online, but in microfiche | + | * ''RM80 Disk Drive Technical Description Manual'' (EP-0RM80-TD-001) - not available online, but in microfiche |
| − | RM80 Disk Drive Service Manual (EP-0RM80-SV-001) - not available online, but in microfiche | + | * ''RM80 Disk Drive Service Manual'' (EP-0RM80-SV-001) - not available online, but in microfiche |
==External links== | ==External links== | ||
| Line 13: | Line 45: | ||
* [http://www.bitsavers.org/pdf/dec/disc/rm05/EK-RMADA-TD-001_Oct80.pdf RM MASSBUS Adapter Technical Description Manual] (EK-RMADA-TD-001) | * [http://www.bitsavers.org/pdf/dec/disc/rm05/EK-RMADA-TD-001_Oct80.pdf RM MASSBUS Adapter Technical Description Manual] (EK-RMADA-TD-001) | ||
| − | [[Category: MASSBUS | + | [[Category: MASSBUS Disk Drives]] |
| − | [[Category: DEC | + | [[Category: DEC Non-removable-media Disks]] |
Latest revision as of 14:23, 18 August 2023
| RM80 | |
| Manufacturer: | DEC |
|---|---|
| Year Introduced: | October, 1980 |
| Drive Controller(s): | RH11, RH70, RH10, RH20, RH780, RH750 |
| Capacity: | 124 Mbytes |
| Transfer Rate: | 1.2 Mbytes/sec |
| Average Access Time: | 33.3 msec |
| Revolutions per Minute: | 3600 |
| 1/2 Revolution Time: | 8.3 msec |
| One Track Seek Time: | 6 msec |
| Average Seek Time: | 25 msec |
| Maximum Seek Time: | 50 msec |
| Total Surfaces: | 7 data, 1 servo |
| Number of Heads: | 14 data, 1 servo (read-only) |
| Tracks per Surface: | 561 (18-bit word mode) 559 (16-bit word mode) |
| Sectors per Track: | 30 (18-bit word mode) 31 (useable; 16-bit word mode) |
| Words per Sector: | 256 (16-bit word mode) |
| Tracks per Inch: | 478 |
| Density: | 6339 (max; inner track) |
| Recording Method: | MFM |
| Start Time: | 20 secs (avg); 40 secs (max) |
| Stop Time: | 9 secs (avg); 13 secs (max) |
| Physical Size: | 26cm x 44cm x 67cm |
| Weight: | 135 lbs (approx) |
| Power Consumption: | 575 watts |
The RM80 Disk Drive was a MASSBUS non-removable-media disk from DEC; it held 124 MB. It was apparently the MASSBUS version of the R80 Disk Drive; it could support either 16- or 18-bit words. It was internally operated by a microprocessor which used 32-bit burst ECC to invisibly repair simple data errors.
It had two heads per surface; not rotationally opposed (to halve maximum access time), but two on each arm; there were thus 1,122 usable tracks on each data surface (in 18-bit word mode; 4 tracks were reserved for maintenance purposes in 16-bit mode). 1 sector per track was reserved for bad block replacement in 16-bit word mode, out of 32 total.
The RM80 can also be connected in a dual-port arrangement, permitting its use by two controllers.
Further reading
- RM80 Disk Drive Technical Description Manual (EP-0RM80-TD-001) - not available online, but in microfiche
- RM80 Disk Drive Service Manual (EP-0RM80-SV-001) - not available online, but in microfiche
