Difference between revisions of "PDP-8"

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| year discontinued = 1969
 
| year discontinued = 1969
 
| architecture = [[PDP-8 architecture|PDP-8]]
 
| architecture = [[PDP-8 architecture|PDP-8]]
| physical address = 32KW (requires optional Type 183)
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| physical address = 32k words (requires optional Type 183)
| virtual address = 4KW
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| virtual address = 4k words
| design type = [[clock]]ed random [[logic]]  
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| design type = [[clock]]ed random [[logic]]
| clock speed = 333KHz
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| clock speed = 1.333 MHz
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| cycle time = 1.5 μseconds
 
| memory speed = 1.5 μseconds
 
| memory speed = 1.5 μseconds
 
| memory mgmt = bank select
 
| memory mgmt = bank select
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Options included:
 
Options included:
  
* Type 183 Memory Extension Control, which was needed to support more than 4K [[word]]s of memory
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* Type 183 Memory Extension Control, which was needed to support more than 4k [[word]]s of memory
 
* Type 184 Memory Module
 
* Type 184 Memory Module
 
* Type 188 Memory Parity
 
* Type 188 Memory Parity
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*[[OS/8]]
 
*[[OS/8]]
 
*[[TSS/8]]
 
*[[TSS/8]]
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*COS-310
  
 
== Emulators ==
 
== Emulators ==
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*[[SIMH]]
 
*[[SIMH]]
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== Application software/Simulation software ==
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Mention in this video regarding a PDP-8 screen running J.H. Conways game of life:
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* [https://www.youtube.com/watch?v=R9Plq-D1gEk Inventing Game of Life - Numberphile]
  
 
{{Nav PDP-8}}
 
{{Nav PDP-8}}

Latest revision as of 12:57, 25 August 2019

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
PDP-8.jpg
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)
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. 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, which was needed to support more than 4k words of memory
  • Type 184 Memory Module
  • 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:

Application software/Simulation software

Mention in this video regarding a PDP-8 screen running J.H. Conways game of life: