Difference between revisions of "PDP-8"
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(for the 2 MHz clock, see "Computer Structures: Readings and Examples", page 120: "A PDP-S/S is one-fifteenth of a PDP-8 at one-half the cost. ...even though the same 2-megahertz logic clock is used in both cases.") |
m (→External links: +one from Paul Allen's collection at the LCM) |
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| Line 4: | Line 4: | ||
| name = PDP-8 | | name = PDP-8 | ||
| image = PDP-8.jpg | | image = PDP-8.jpg | ||
| + | | imgwidth = 150px | ||
| caption = An original, transistorized PDP-8 | | caption = An original, transistorized PDP-8 | ||
| manufacturer = [[Digital Equipment Corporation|DEC]] | | manufacturer = [[Digital Equipment Corporation|DEC]] | ||
| Line 11: | Line 12: | ||
| year discontinued = 1969 | | year discontinued = 1969 | ||
| architecture = [[PDP-8 architecture|PDP-8]] | | architecture = [[PDP-8 architecture|PDP-8]] | ||
| − | | physical address = 32k words (requires optional Type 183) | + | | physical address = 32k words (requires optional Type 183 Memory Extension) |
| virtual address = 4k words | | virtual address = 4k words | ||
| − | | design type = [[clock]]ed random [[logic]] | + | | design type = [[clock]]ed random [[logic]] |
| − | | clock speed = | + | | clock speed = 1.333 MHz |
| − | | | + | | cycle time = 1.5 μseconds |
| memory speed = 1.5 μseconds | | memory speed = 1.5 μseconds | ||
| memory mgmt = bank select | | memory mgmt = bank select | ||
| Line 31: | Line 32: | ||
--> | --> | ||
}} | }} | ||
| + | The '''PDP-8''' (now often known as a '''Straight 8'''; the name dates from the late 60's, apparently adopted to allow disambiguation), the first model of the [[PDP-8 family]], was [[Digital Equipment Corporation|DEC]]'s major breakthrough, and now considered the first really successful [[minicomputer]]. It was, by a significant amount, the cheapest computer yet made at the time. | ||
| − | The | + | The PDP-8 was constructed with discrete [[transistor]]s, packaged into DEC's [[FLIP CHIP]] technology; mostly R- and S-series, in [[DEC card form factor|standard-length single-height]] (width) format, with a few dual-height. |
| − | + | It could perform an addition to the [[accumulator]] in 3.0 μseconds, and a 12 by 12 bit multiplication with 24 bit result in 15 μseconds (average; range 9 to 21), using the optional math extension hardware (below). | |
==Options== | ==Options== | ||
| Line 40: | Line 42: | ||
Options included: | Options included: | ||
| − | * Type 183 Memory Extension Control, | + | * Type 183 Memory Extension Control, [[bank switching]] needed to support more than 4K [[word]]s of memory |
| − | * Type 184 Memory Module | + | * Type 184 4KW Memory Module (up to 7) |
* Type 188 Memory Parity | * Type 188 Memory Parity | ||
| − | * Type 182 Extended Arithmetic Element, which supported [[hardware]] integer multiplication and division, multi-[[bit]] double-word shifts, and [[normalization]] | + | * Type 182 [[Extended Arithmetic Element]], which supported [[hardware]] integer multiplication and division, multi-[[bit]] double-word shifts, and [[normalization]] |
== Operating Systems == | == Operating Systems == | ||
| − | The PDP-8 could run various operating | + | The PDP-8 could run various [[operating system]]s including: |
*[[OS/8]] | *[[OS/8]] | ||
*[[TSS/8]] | *[[TSS/8]] | ||
| Line 58: | Line 60: | ||
*[[SIMH]] | *[[SIMH]] | ||
| − | == | + | ==External links== |
| − | |||
| − | |||
| − | * [https://www.youtube.com/watch?v=R9Plq-D1gEk Inventing Game of Life - Numberphile] | + | * [http://www.bitsavers.org/pdf/dec/pdp8/pdp8 PDP-8] - Original PDP-8 documents at Bitsavers |
| + | * [https://www.youtube.com/watch?v=R9Plq-D1gEk Inventing Game of Life - Numberphile] - PDP-8 screen running J.H. Conways game of life | ||
| + | * [https://onlineonly.christies.com/s/firsts-history-computing-paul-g-allen-collection/pdp-8-minicomputer-chess-set-115/230053 PDP-8 minicomputer] - from [[Paul Allen]]'s collection at the [[Living Computer Museum|LCM]], includes several images | ||
{{Nav PDP-8}} | {{Nav PDP-8}} | ||
| Line 68: | Line 70: | ||
[[Category: PDP-8s]] | [[Category: PDP-8s]] | ||
[[Category: DEC Systems]] | [[Category: DEC Systems]] | ||
| + | [[Category: 12-bit Computers]] | ||
Latest revision as of 21:54, 23 April 2025
This article is about the first PDP-8, which had that name without a model suffix. For information about PDP-8's in general, see PDP-8 family.
| PDP-8 | |
 An original, transistorized PDP-8 | |
| Manufacturer: | DEC |
|---|---|
| Architecture: | PDP-8 |
| Year Introduced: | 1965 |
| Year Discontinued: | 1969 |
| Form Factor: | minicomputer |
| Word Size: | 12 bits |
| Logic Type: | DTL |
| Design Type: | clocked random logic |
| Clock Speed: | 1.333 MHz |
| Cycle Time: | 1.5 μseconds |
| Memory Speed: | 1.5 μseconds |
| Physical Address Size: | 32k words (requires optional Type 183 Memory Extension) |
| Virtual Address Size: | 4k words |
| Memory Management: | bank select |
| Bus Architecture: | Negative I/O Bus |
| Predecessor(s): | PDP-5 |
| Successor(s): | PDP-8/I |
| Price: | US$18,500 |
The PDP-8 (now often known as a Straight 8; the name dates from the late 60's, apparently adopted to allow disambiguation), the first model of the PDP-8 family, was DEC's major breakthrough, and now considered the first really successful minicomputer. It was, by a significant amount, the cheapest computer yet made at the time.
The PDP-8 was constructed with discrete transistors, packaged into DEC's FLIP CHIP technology; mostly R- and S-series, in standard-length single-height (width) format, with a few dual-height.
It could perform an addition to the accumulator in 3.0 μseconds, and a 12 by 12 bit multiplication with 24 bit result in 15 μseconds (average; range 9 to 21), using the optional math extension hardware (below).
Options
Options included:
- Type 183 Memory Extension Control, bank switching needed to support more than 4K words of memory
- Type 184 4KW Memory Module (up to 7)
- Type 188 Memory Parity
- Type 182 Extended Arithmetic Element, which supported hardware integer multiplication and division, multi-bit double-word shifts, and normalization
Operating Systems
The PDP-8 could run various operating systems including:
Emulators
There are various emulators for PDP-8 systems including:
External links
- PDP-8 - Original PDP-8 documents at Bitsavers
- Inventing Game of Life - Numberphile - PDP-8 screen running J.H. Conways game of life
- PDP-8 minicomputer - from Paul Allen's collection at the LCM, includes several images
| v • d • e PDP-8 Computers, Software and Peripherals |
|---|
| PDP-8s: PDP-5 • PDP-8 • LINC-8 • PDP-8/S • PDP-8/I • PDP-8/L • PDP-12 • PDP-8/E • PDP-8/F • PDP-8/M • PDP-8/A
Workstations: VT78 Also: PDP-8 family • PDP-8 architecture • PDP-8 Memory Extension units |
