Difference between revisions of "List of Programmed Data Processors"

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'''Programmed Data Processor''' was the name adopted by [[Digital Equipment Corporation]] for all its early computers. (Reportedly, it was adopted to avoid worrying its early venture capital backers; at the time, almost all computers were large [[mainframe]]s, and DEC's founders were concerned that if it appeared that they intended to compete in that market, they wouldn't be able to get funding.)
 
'''Programmed Data Processor''' was the name adopted by [[Digital Equipment Corporation]] for all its early computers. (Reportedly, it was adopted to avoid worrying its early venture capital backers; at the time, almost all computers were large [[mainframe]]s, and DEC's founders were concerned that if it appeared that they intended to compete in that market, they wouldn't be able to get funding.)
  
The name was dropped starting with the [[VAX]]. The other PDP families (most included more than one model) were:
+
The name was dropped starting with the [[VAX]]. The other PDP families which became actual products for DEC (most included more than one model) were:
  
 
{| class="wikitable"
 
{| class="wikitable"
 
! Family/Machine !! [[Word]] Size !! Comment
 
! Family/Machine !! [[Word]] Size !! Comment
 
|-
 
|-
| [[PDP-1]] || 18
+
| [[PDP-1]] || 18 || The first PDP
|-
 
| PDP-2 || 24 || Never designed
 
|-
 
| PDP-2 ½ || || "Casino" by Ed Rawson of the American Science Institute.
 
 
|-
 
|-
 
| [[PDP-3]] || 36 || Only one built, not by DEC
 
| [[PDP-3]] || 36 || Only one built, not by DEC
 
|-
 
|-
| [[PDP-4]] || 18
+
| [[PDP-4]] || 18 || Simplified and cost-reduced 18-bit machine.
 
|-
 
|-
| [[PDP-5]] || 12 || First [[minicomputer]]
+
| [[PDP-5]] || 12 || The first [[minicomputer]]
 
|-
 
|-
| [[PDP-6]] || 36
+
| [[PDP-6]] || 36 || DEC's first "large" machine; immediate predecessor to the PDP-10 family
 
|-
 
|-
 
| [[PDP-7]] || 18 || Original [[UNIX]] machine
 
| [[PDP-7]] || 18 || Original [[UNIX]] machine
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| [[PDP-9]] || 18
 
| [[PDP-9]] || 18
 
|-
 
|-
| PDP-24 || || Unconfirmed, mentioned in [http://bitsavers.org/pdf/dec/pdp-x/03.pdf PDP-X memo 3].
+
| [[PDP-10]] || 36 || DEC's [[mainframe]].  Renamed [[DECsystem-10]], and later added [[DECSYSTEM-20]].
|-
 
| [[PDP-10]] || 36 || DEC's mainframe
 
 
|-
 
|-
 
| [[PDP-11]] || 16
 
| [[PDP-11]] || 16
Line 36: Line 30:
 
| [[PDP-14]] || 12 || Industrial controller
 
| [[PDP-14]] || 12 || Industrial controller
 
|-
 
|-
| [[PDP-15]] || 18
+
| [[PDP-15]] || 18 || The last 18-bit PDP
 +
|-
 +
| [[PDP-16]] ||   || Not an actual computer; custom industrial controllers built out of [[Register Transfer Module]]s
 +
|}
 +
 
 +
A number of other PDPs never existed as real machines, are misnomers, or jokes:
 +
 
 +
{| class="wikitable"
 +
! Family/Machine !! Word Size !! Comment
 +
|-
 +
| [[PDP-2]] || 24 || Never designed.
 +
|-
 +
| PDP-2½ || ? || Jocular moniker for "[[CASINO]]" by Ed Rawson of the American Science Institute.
 +
|-
 +
| PDP-13 || — || The unlucky number 13 was skipped.
 +
|-
 +
| PDP-20 || 36 || ''Not a real name!''  Sometimes used for DECSYSTEM-20 computers. 
 +
|-
 +
| PDP-24 || 24? || Unconfirmed, mentioned in [http://bitsavers.org/pdf/dec/pdp-x/03.pdf PDP-X memo 3].
 
|-
 
|-
| [[PDP-16]] ||   || Not an actual computer; custom industrial controllers built out of [[Register Transfer Modules]] 
+
| [[PDP-K]] || 18 || Intended as a bridge between the PDP-15 and the PDP-10 family, with a PDP-11-like instruction set.
 
|-
 
|-
| PDP-20 || || ''Not a real name!''  Sometimes used for DEC-20 computers.
+
| [[PDP-X]] || 16 || An alternative to the PDP-11.
 
|}
 
|}
  

Latest revision as of 09:12, 3 December 2024

Programmed Data Processor was the name adopted by Digital Equipment Corporation for all its early computers. (Reportedly, it was adopted to avoid worrying its early venture capital backers; at the time, almost all computers were large mainframes, and DEC's founders were concerned that if it appeared that they intended to compete in that market, they wouldn't be able to get funding.)

The name was dropped starting with the VAX. The other PDP families which became actual products for DEC (most included more than one model) were:

Family/Machine Word Size Comment
PDP-1 18 The first PDP
PDP-3 36 Only one built, not by DEC
PDP-4 18 Simplified and cost-reduced 18-bit machine.
PDP-5 12 The first minicomputer
PDP-6 36 DEC's first "large" machine; immediate predecessor to the PDP-10 family
PDP-7 18 Original UNIX machine
PDP-8 12 First commercially successful minicomputer
PDP-9 18
PDP-10 36 DEC's mainframe. Renamed DECsystem-10, and later added DECSYSTEM-20.
PDP-11 16
PDP-12 12 Laboratory computer, replacement for the LINC-8
PDP-14 12 Industrial controller
PDP-15 18 The last 18-bit PDP
PDP-16   Not an actual computer; custom industrial controllers built out of Register Transfer Modules

A number of other PDPs never existed as real machines, are misnomers, or jokes:

Family/Machine Word Size Comment
PDP-2 24 Never designed.
PDP-2½  ? Jocular moniker for "CASINO" by Ed Rawson of the American Science Institute.
PDP-13 The unlucky number 13 was skipped.
PDP-20 36 Not a real name! Sometimes used for DECSYSTEM-20 computers.
PDP-24 24? Unconfirmed, mentioned in PDP-X memo 3.
PDP-K 18 Intended as a bridge between the PDP-15 and the PDP-10 family, with a PDP-11-like instruction set.
PDP-X 16 An alternative to the PDP-11.

External links