[go: nahoru, domu]
Jump to content

Commodore 8050: Difference between revisions

From Wikipedia, the free encyclopedia
Browse history interactively
← Previous edit
Content deleted Content added
VisualWikitext
improved link
Rescuing 1 sources and tagging 0 as dead.) #IABot (v2.0.9.5
 
(26 intermediate revisions by 15 users not shown)
Line 1: Line 1:
{{multiple issues|
{{more footnotes|date=March 2012}}
{{refimprove|date=March 2012}}
}}
{{Infobox information appliance <!-- https://en.wikipedia.org/wiki/Template:Infobox_information_appliance -->
{{Infobox information appliance <!-- https://en.wikipedia.org/wiki/Template:Infobox_information_appliance -->
| name = Commodore 8050/8250
| name = Commodore 8050
| title =
| title =
| image = Commodore CBM 2001 & 8050.jpg
| image = Commodore CBM 2001 & 8050.jpg
Line 10: Line 6:
| manufacturer = Commodore Business Machines, Inc.
| manufacturer = Commodore Business Machines, Inc.
| type = Floppy drive
| type = Floppy drive
| releasedate = 8050: {{Start date|1980||}}<ref name=oc4032>{{Cite web|author= |accessdate=2016-04-02 |date=2013-12-10 |publication-date= |title=Commodore PET 4032 computer |pages= |publisher= |url=http://www.oldcomputers.net/pet4032.html |quote=1980: May - Commodore Business Machines introduces the CBM 8050 dual 5 1/4-inch floppy disk drive unit. }}</ref><ref name=pcmu/>
| releasedate = {{Start date|1980||}}<ref name=pcmu>{{Cite web|title=Commodore SuperPET|url=http://www.pcmuseum.ca/details.asp?id=72|access-date=2016-04-02|archive-date=2010-06-20|archive-url=https://web.archive.org/web/20100620003210/http://www.pcmuseum.ca/details.asp?id=72|url-status=dead}}</ref>
| price = {{USD|1695|1980|round=-2}}<ref name=pcmu/>
| price <!--intro--> = 8050: USD 1695 (1980) USD {{Inflation|US|1695|1980|fmt=c|r=-2}} ({{CURRENTYEAR}} equivalent)<ref name=pcmu>{{Cite web|author= |accessdate=2016-04-02 |date= |publication-date= |title=The Personal Computer Museum, Brantford, Ontario, CANADA - Recycle, donate, and browse your old computers, electronics, video games, and software |pages= |publisher= |url=http://www.pcmuseum.ca/details.asp?id=72 |quote= }}</ref>
| discontinued =
| discontinued =
| media = 2 × 5¼" double-sided, double-density<ref name=serv85>{{cite book |date=1985 |title=Service Manual 8050 • 8250 Dual Disk Drives |publisher=Commodore Business Machines, Inc. |url=http://www.primrosebank.net/computers/pet/documents/8050_8250_service_manual.pdf |pages=1, 5 }}</ref>
| media = 2x 5¼" [[floppy disk]]<br> 8050: [[Floppy disk format#Single Sided, Double Density|SS]] DD 8250: DS DD
| os = [[Commodore DOS|CBM DOS 2.5/2.7]]<ref name=coca>{{Cite web|author= |accessdate=2016-04-02 |date= |publication-date=2011-03-30 |title=Manuals &#124; Technical Comparison of Commodore 1541 2040 4040 8050 8250 Drives |pages= |publisher= |url=http://www.commodore.ca/manuals/commodore_1541_4040_8050_8250_comparison.htm |quote=DOS version(s) 2.6 2.6 2.1/2.7 2.5/2.7 2.7 }}</ref>
| os = [[Commodore DOS|CBM DOS 2.5/2.7]]<ref name=petindex>{{Cite web |title=PET index - Disk drives |url=http://6502.org/users/andre/petindex/drives/index.html }}</ref>
| power = 120 V 60 Hz 1 A fuse {{nowrap|(8050 50 W}} ; {{nowrap|8250 60 W)}}<ref name=serv85>{{Cite web|author= |accessdate=2016-04-02 |date=1985 |publication-date=2015-04-16 |title=Service manual 8050 * 8250 Dual disk drives June 1985 PN-314011-03 |pages= |publisher=Commodore Business Machines, Inc. 1200 Wilson Drive, West Chester, Pennsylvania 19380 U.S.A. |url=http://www.primrosebank.net/computers/pet/documents/8050_8250_service_manual.pdf |quote= }}</ref>
| power = 110-117 V, 220-24 0V, 50 W<ref name=usemancbm525>{{cite book |title=User's Manual for CBM 5¼-inch Dual Floppy Disk Drives |publisher=Commodore Business Machines, Inc. |date=1980 |url=http://www.classiccmp.org/cini/pdf/Commodore/CBM%202040-3040-4040-8050%20Disk%20Drive%20Manual.pdf |pages=5–6}}</ref>
| cpu = 2x [[MOS Technology 6502|MOS 6502]] @ {{nowrap|1 MHz}}<ref name=serv85/>
| cpu = 2 × [[MOS Technology 6502|MOS 6502]] @ {{nowrap|1 MHz}} <ref name=serv85/>
| memory = 4 kB RAM 16 kB ROM<ref name=serv85/>
| memory = 4&nbsp;KB SRAM (8 × [[Random-access memory#SRAM|2114]]), 16&nbsp;KB ROM (2 × [[Read-only memory#Timeline|2364]]) <ref name=serv85/>
| storage = 8050: 521 kB/drive<br> 8250: 1042 kB/drive<ref name=coca/><ref name=pcmu/><ref name=mitvice>{{cite web|title=Commodore compatible Disk Drives
| storage = 521 KB/side, 1042 KB/disk<ref name=usemancbm525/>
| connectivity = Parallel [[IEEE-488]]<ref name=serv85/>
|date=1996-06-12
| dimensions = {{convert|6.5|×|15.0|×|14.35|in|abbr=on}}<ref name=usemancbm525/>
|accessdate=2016-04-30
| weight = {{convert|28|lb|abbr=on}}<ref name=diskrefD9090>{{cite book |title=Commodore Disk Reference Manual for D9090 D9060 8250 8050 4040 2031 |publisher=Commodore Business Machines, Inc. |url=ftp://www.zimmers.net/pub/cbm/manuals/drives/Disk_Reference_Manual_(D9090_D9060_8250_8050_4040_2031).pdf |pages=5–6, 8–9}}</ref>
|url=http://web.mit.edu/jhawk/mnt/ss.b/vice-0.12.0/doc/drive_info}}</ref><!-- ref:coca specify capacity ref:pcmu hints on capacity per disk, ref:mitvice specify capacity per drive unambiguously -->
| compatibility= [[Commodore PET|PET]], 4000-series, 8000-series, [[Commodore CBM-II|B128]];<ref name=serv85/> [[Commodore 64]], [[VIC-20]] with IEEE-488 adapter<ref name=coca>{{Cite web |accessdate=2016-04-02 |publication-date=2011-03-30 |title=Manuals &#124; Technical Comparison of Commodore 1541 2040 4040 8050 8250 Drives |url=http://www.commodore.ca/manuals/commodore_1541_4040_8050_8250_comparison.htm |archive-url=https://web.archive.org/web/20081011191542/http://www.commodore.ca/manuals/commodore_1541_4040_8050_8250_comparison.htm |archive-date=2008-10-11 |url-status=dead }}</ref>
| connectivity = Parallel [[IEEE-488]]<ref>{{Cite web|author= |accessdate=2016-04-02 |date=2004-09-10 |publication-date= |title=d8050b.jpg |pages= |publisher= |url=http://classiccmp.org/dunfield/pet/h/d8050b.jpg |quote= }}<!--source: http://classiccmp.org/dunfield/pet/index.htm--></ref> 1.8 kB/s<ref name=coca/><!-- 400 byte/s<ref name=serv85/> -->
⚫
| predecessor = [[Commodore 4040]]
| dimensions =
| weight =
| compatibility= [[Commodore PET|PET]], 4000-series, 8000-series, [[Commodore CBM-II|B128]],<ref name=serv85/> [[Commodore 64]], [[Commodore VIC-20|VIC-20]]<ref name=coca/>
⚫
| predecessor =
| successor =
| successor =
| related =
| related =
}}
}}


The '''Commodore 8050''' and '''Commodore 8250''' are dual-unit 5¼" [[floppy disk]] drives for [[Commodore International]] computers. They use a wide rectangular steel case form similar to that of the [[Commodore 4040]], and use the [[IEEE-488]] interface common to [[Commodore PET|Commodore PET/CBM]] computers.
The '''Commodore 8050''', '''Commodore 8250''', and '''Commodore SFD-1001''' are 5¼-inch [[floppy disk drive]]s manufactured by [[Commodore International]], primarily for its 8-bit [[Commodore CBM-II|CBM]] and [[Commodore PET|PET]] series of computers. The drives offered improved storage capacities over previous Commodore drive models.


They are notable for the disk drive having twice the processing power than the connected computer in having two 1MHz 6502 processors sharing operation of communication and disk operation, though only supporting 4k of main memory. The disk operating system is actually contained within the disk drive unit with commands being sent via the 8 bit GPIB interface where the system decodes the message and carries out the requested operation such as formatting a disk without further involvement from the connected computer.
The '''8050''' is a single-sided drive, whereas the '''8250''' can use both sides of a disk simultaneously. Both use a [[List of floppy disk formats#Physical composition|quad density]] format storing approximately 0.5 megabyte per side. The density of media is similar to later PC [[high density]] floppy disks, but with the original 300-[[oersted]] coercivity used by double density drives. The 8050 and 8250 did not write with enough power to use 600-oersted PC high density disks reliably. As quad-density disks were rare even at the time that these were current models, users quickly found that typical [[double density]] floppy disks had enough magnetic media density to work in these drives.


== Specifications ==
These drives are not '''dual-mode''', so they cannot read or write disks formatted by the more common lower-capacity [[Commodore 1541]] or [[Commodore 4040]] models.
All three models utilize 5¼-inch [[double-density]] [[floppy disk]]s with a track spacing of 100 tracks-per-inch, for a total of 77 logical tracks per side.{{efn|5¼-inch double-density drives with a track spacing of 96 or 100 tpi are commonly referred to as "quad-density" drives.}} Data is encoded using Commodore's proprietary [[group coded recording#Commodore|group coded recording]] scheme. [[Soft sector#Sectoring|Soft sectoring]] is used for track alignment. Like most other Commodore disk drives, these drives utilize [[zone bit recording]] to maintain an [[Areal density (computer storage)|average bit density]] across the entire disk. Formatted capacity is approximately 0.5 megabyte per side, or 1 megabyte (1,066,496 bytes) in 4166 blocks total.<ref name=usemancbm525/><ref name=diskrefD9090 /><ref name=floodgap>{{Cite web|url=http://www.floodgap.com/retrobits/ckb/secret/periph.html|title=Secret Weapons of Commodore: The Disk Drives|author=Cameron Kaiser}}</ref>


The '''8050''' is a single-sided drive, whereas the '''8250''' and '''SFD-1001''' are double-sided drives. Double-sided drives can fully read and write to disks formatted by single-sided drives, but single-sided drives can only read and write to the bottom side of disks formatted by double-sided drives.<ref name=petindex/><ref name=diskrefD9090/>
Some variants of these drives exist. The '''Commodore 8250LP''' is the '''8250''' in a lower profile, tan-colored case.<ref name=m65>{{Cite web|author= |accessdate=2016-04-02 |date= |publication-date=2010 |title=Commodore 8250 LP Dual Disk Drive |pages= |publisher= |url=http://www.mos6502.com/my-commodore-collection/disk-drives/commodore-8250-lp-dual-disk-drive/ |quote= }}</ref><ref name=ncrep>{{Cite web|author= |accessdate=2016-04-02 |date=2013-12-17 |publication-date= |title=Restoration & Repair A Commodore Dual Disk 8250 LP |pages= |publisher= |url=http://www.nightfallcrew.com/17/12/2013/restoration-repair-a-commodore-dual-disk-8250-lp/ |quote= }}</ref> The '''Commodore SFD-1001''' is a single-drive version of the '''8250''' in a [[Commodore 1541]]-style case<ref name=pcmu/> (similarly to the [[Commodore 2031|Commodore 2031LP]]), often used by [[bulletin board system]]s for their physical similarity to '''1541'''s and high capacity and speed.

Both the '''8050''' and '''8250''' are housed in a dual-drive case similar to the [[Commodore 4040]] drive. The '''SFD-1001''' is housed in a single-drive case similar to the [[Commodore 1541]]. The '''8250LP''', a low-profile revision of the '''8250''', is housed in a shorter dual-drive case that is stylistically similar to the '''SFD-1001'''. All models include an internal power supply and an [[IEEE-488]] data connector on the rear of the case. The '''8050''' and '''8250''' include latch sensors that can detect when a disk is inserted or removed.<ref name=floodgap/><ref name=ncrep>{{Cite web|accessdate=2016-04-02 |date=2013-12-17 |title=Restoration & Repair A Commodore Dual Disk 8250 LP |url=http://www.nightfallcrew.com/17/12/2013/restoration-repair-a-commodore-dual-disk-8250-lp/ }}</ref><ref name=m65>{{Cite web|author= |accessdate=2016-04-02 |date= |publication-date=2010 |title=Commodore 8250 LP Dual Disk Drive |pages= |publisher= |url=http://www.mos6502.com/my-commodore-collection/disk-drives/commodore-8250-lp-dual-disk-drive/ |quote= }}</ref>

These drives are not ''dual-mode'', so they cannot read or write 5¼-inch disks formatted by lower-capacity 48-tpi models, such as the Commodore 1541 or 4040. They also cannot read or write 5¼-inch disks formatted by 96-tpi drives, such as the 640 kilobyte IBM PC disk or 880 kilobyte Commodore [[Amiga]] disk, due to the minor difference in track spacing. Lastly, they cannot read or write high-density 5¼-inch disks due to both the difference in track spacing and the difference in write head coercivity (300-[[oersted]] for double-density, 600-oersted for high-density).<ref name=coca/><ref name=floodgap/>


== Disk Layout ==
== Disk Layout ==
Line 80: Line 78:
* [[Zone bit recording]]
* [[Zone bit recording]]
* [[Group coded recording]]
* [[Group coded recording]]

== Notes ==
{{notelist}}


== References ==
== References ==
⚫
<references/>
* [http://cbmpet.com/lib/d/4/ Commodore 8050 Brochure]

==External links==
* [http://members.optusnet.com.au/spacetaxi64/MAIN/SFD1001.htm optusnet.com.au/../SFD1001.htm] TOOLS specifically for the SFD1001 & 8250 Drives.
* [http://members.optusnet.com.au/spacetaxi64/MAIN/SFD1001.htm optusnet.com.au/../SFD1001.htm] TOOLS specifically for the SFD1001 & 8250 Drives.
* [http://www.floodgap.com/retrobits/ckb/ Commodore Knowledge Base]
* [http://www.floodgap.com/retrobits/ckb/ Commodore Knowledge Base]
* [http://www.commodore.ca/manuals/commodore_1541_4040_8050_8250_comparison.htm Technical comparison of Commodore floppy drives] (with drive capacities)
* [https://web.archive.org/web/20081011191542/http://www.commodore.ca/manuals/commodore_1541_4040_8050_8250_comparison.htm Technical comparison of Commodore floppy drives] (with drive capacities)
* [http://www.commodoremagazine.com/2010/05/commodore-dual-disk-drives.html Commodore Dual Disk Drives]
* [https://web.archive.org/web/20110203060910/http://www.commodoremagazine.com/2010/05/commodore-dual-disk-drives.html Commodore Dual Disk Drives]
* [http://classiccmp.org/dunfield/pet/index.htm Daves Old Computers - Commodore PET] (floppy drive images and info)
* [http://classiccmp.org/dunfield/pet/index.htm Daves Old Computers - Commodore PET] (floppy drive images and info)
⚫
<references/>


{{Commodore disk drives}}
{{Commodore disk drives}}


[[Category:CBM floppy disk drives]]

{{microcompu-stub}}

Latest revision as of 19:23, 18 December 2023

Commodore 8050
Commodore 8050 floppy-disk drive, with CBM 2001 PC
ManufacturerCommodore Business Machines, Inc.
TypeFloppy drive
Release date1980 (1980)[1]
Introductory priceUS$1,695 (equivalent to $6,300 in 2023)[1]
Media2 × 5¼" double-sided, double-density[2]
Operating systemCBM DOS 2.5/2.7[3]
CPU2 × MOS 6502 @ 1 MHz [2]
Memory4 KB SRAM (8 × 2114), 16 KB ROM (2 × 2364) [2]
Storage521 KB/side, 1042 KB/disk[4]
ConnectivityParallel IEEE-488[2]
Power110-117 V, 220-24 0V, 50 W[4]
Dimensions6.5 in × 15.0 in × 14.35 in (165 mm × 381 mm × 364 mm)[4]
Mass28 lb (13 kg)[5]
Backward
compatibility		PET, 4000-series, 8000-series, B128;[2] Commodore 64, VIC-20 with IEEE-488 adapter[6]
PredecessorCommodore 4040

The Commodore 8050, Commodore 8250, and Commodore SFD-1001 are 5¼-inch floppy disk drives manufactured by Commodore International, primarily for its 8-bit CBM and PET series of computers. The drives offered improved storage capacities over previous Commodore drive models.

They are notable for the disk drive having twice the processing power than the connected computer in having two 1MHz 6502 processors sharing operation of communication and disk operation, though only supporting 4k of main memory. The disk operating system is actually contained within the disk drive unit with commands being sent via the 8 bit GPIB interface where the system decodes the message and carries out the requested operation such as formatting a disk without further involvement from the connected computer.

Specifications[edit]

All three models utilize 5¼-inch double-density floppy disks with a track spacing of 100 tracks-per-inch, for a total of 77 logical tracks per side.[a] Data is encoded using Commodore's proprietary group coded recording scheme. Soft sectoring is used for track alignment. Like most other Commodore disk drives, these drives utilize zone bit recording to maintain an average bit density across the entire disk. Formatted capacity is approximately 0.5 megabyte per side, or 1 megabyte (1,066,496 bytes) in 4166 blocks total.[4][5][7]

The 8050 is a single-sided drive, whereas the 8250 and SFD-1001 are double-sided drives. Double-sided drives can fully read and write to disks formatted by single-sided drives, but single-sided drives can only read and write to the bottom side of disks formatted by double-sided drives.[3][5]

Both the 8050 and 8250 are housed in a dual-drive case similar to the Commodore 4040 drive. The SFD-1001 is housed in a single-drive case similar to the Commodore 1541. The 8250LP, a low-profile revision of the 8250, is housed in a shorter dual-drive case that is stylistically similar to the SFD-1001. All models include an internal power supply and an IEEE-488 data connector on the rear of the case. The 8050 and 8250 include latch sensors that can detect when a disk is inserted or removed.[7][8][9]

These drives are not dual-mode, so they cannot read or write 5¼-inch disks formatted by lower-capacity 48-tpi models, such as the Commodore 1541 or 4040. They also cannot read or write 5¼-inch disks formatted by 96-tpi drives, such as the 640 kilobyte IBM PC disk or 880 kilobyte Commodore Amiga disk, due to the minor difference in track spacing. Lastly, they cannot read or write high-density 5¼-inch disks due to both the difference in track spacing and the difference in write head coercivity (300-oersted for double-density, 600-oersted for high-density).[6][7]

Disk Layout[edit]

Track Sectors Per Track
(256 bytes)		 Sectors
 1-39, 78-116 29 1131
40-53, 117-130 27 378
54-64, 131-141 25 275
65-77, 142-154 23 299

Total Sectors: 2083 (4166 for the 8250)

The disk header is on 39/0 (track 39, sector 0), with the directory residing on the remaining 28 sectors of track 39.

Header Layout 39/0 

$00–01 T/S reference to the first BAM (block availability map) sector
    02 DOS version ('C')
 06-16 Disk label, $A0 padded
 18-19 Disk ID
 1B-1C DOS type('2C')

The BAM (block availability map) begins on 38/0 (track 38, sector 0), and continues on 38/3. On the 8250, the BAM extends further to 38/6 and 38/9. The remaining sectors on track 38 are available for general use.

BAM Layout 38/0, 3, (6, 9) 

$00–01 T/S reference to the next BAM sector, or 00/FF if last.
    02 DOS version ('C')
    04 Lowest BAM track in this block
    05 Highest+1 BAM track in this block
 06-FF BAM for 50 tracks

See also[edit]

Notes[edit]

  1. ^ 5¼-inch double-density drives with a track spacing of 96 or 100 tpi are commonly referred to as "quad-density" drives.

References[edit]

  1. ^ a b "Commodore SuperPET". Archived from the original on 2010-06-20. Retrieved 2016-04-02.
  2. ^ a b c d e Service Manual 8050 • 8250 Dual Disk Drives (PDF). Commodore Business Machines, Inc. 1985. pp. 1, 5.
  3. ^ a b "PET index - Disk drives".
  4. ^ a b c d User's Manual for CBM 5¼-inch Dual Floppy Disk Drives (PDF). Commodore Business Machines, Inc. 1980. pp. 5–6.
  5. ^ a b c Commodore Disk Reference Manual for D9090 D9060 8250 8050 4040 2031 (PDF). Commodore Business Machines, Inc. pp. 5–6, 8–9.
  6. ^ a b "Manuals | Technical Comparison of Commodore 1541 2040 4040 8050 8250 Drives". 2011-03-30. Archived from the original on 2008-10-11. Retrieved 2016-04-02.
  7. ^ a b c Cameron Kaiser. "Secret Weapons of Commodore: The Disk Drives".
  8. ^ "Restoration & Repair A Commodore Dual Disk 8250 LP". 2013-12-17. Retrieved 2016-04-02.
  9. ^ "Commodore 8250 LP Dual Disk Drive". 2010. Retrieved 2016-04-02.

External links[edit]

Retrieved from "https://en.wikipedia.org/w/index.php?title=Commodore_8050&oldid=1190589879"