Difference between revisions of "PDP-1"

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m (External links: +MIT-RLE PDP-1 material at Bitsavers)
(RLE PDP-1 was the nucleus for early hacker culture at MIT)
 
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Standard peripherals included a [[paper tape]] reader and punch, and a [[terminal]]. Optional peripherals included [[graphics]] [[display]]s, a [[light pen]], [[line printer]], [[punched card]] reader and punch, and [[magnetic tape]] [[device controller|controller]] and [[magnetic tape drive|drives]]. <!-- Two different [[magnetic storage|magnetic]] [[drum]] [[secondary storage]] systems (xx) -->
 
Standard peripherals included a [[paper tape]] reader and punch, and a [[terminal]]. Optional peripherals included [[graphics]] [[display]]s, a [[light pen]], [[line printer]], [[punched card]] reader and punch, and [[magnetic tape]] [[device controller|controller]] and [[magnetic tape drive|drives]]. <!-- Two different [[magnetic storage|magnetic]] [[drum]] [[secondary storage]] systems (xx) -->
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 +
A PDP-1 at [[Massachusetts Institute of Technology|MIT]]'s [[Research Laboratory of Electronics|RLE]] served as the nucleus for early [[hacker]] culture at MIT.
  
 
==Technical details==
 
==Technical details==
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* [http://www.bitsavers.org/pdf/dec/pdp1 PDP-1] - Original PDP-1 documents at [[Bitsavers]]
 
* [http://www.bitsavers.org/pdf/dec/pdp1 PDP-1] - Original PDP-1 documents at [[Bitsavers]]
* [http://www.bitsavers.org/pdf/mit/rle_pdp1/ - MIT-RLE PDP-1 material at Bitsavers
+
* [http://www.bitsavers.org/pdf/mit/rle_pdp1/ MIT-RLE PDP-1] - material at Bitsavers
 
* [https://www.computerhistory.org/pdp-1/_media/pdf/DEC.pdp_1.102664938.pdf PDP-1 and PDP-3 brochure]
 
* [https://www.computerhistory.org/pdp-1/_media/pdf/DEC.pdp_1.102664938.pdf PDP-1 and PDP-3 brochure]
 
* [https://www.computerhistory.org/pdp-1/_media/pdf/DEC.pdp_1.pulse_height_anlayzer.1963.102664958.pdf A time-shared computer for real-time information processing], 1963
 
* [https://www.computerhistory.org/pdp-1/_media/pdf/DEC.pdp_1.pulse_height_anlayzer.1963.102664958.pdf A time-shared computer for real-time information processing], 1963

Latest revision as of 22:18, 27 February 2024


PDP-1
Manufacturer: Digital Equipment Corporation
Year First Shipped: 1960
Form Factor: small computer
Word Size: 18 bits
Logic Type: micro-alloy diffused transistor System Modules
Memory Speed: 5 μsec (read/write cycle time)
Physical Address Size: 16 bits (64K words)
Virtual Address Size: 12 bits
Successor(s): PDP-4
Price: US$120K (4KW system)


The PDP-1 was the first computer built by Digital Equipment Corporation. It was an 18-bit machine; a load-store architecture, with a single accumulator. Around 50 were built.

The basic PDP-1 included 4KW of core main memory; an optional Type 15 Memory Extension Control allowed (via bank switching) the addition of up to fifteen additional 4KW Type 12 Core Memory Modules, for a maximum total of 64KW.

The later optional Type 10 Automatic Multiply and Divide added instructions to perform multiplication and division at high speed in hardware (previously, they had been done in software subroutines, albeit with support from specialized instructions).

Standard peripherals included a paper tape reader and punch, and a terminal. Optional peripherals included graphics displays, a light pen, line printer, punched card reader and punch, and magnetic tape controller and drives.

A PDP-1 at MIT's RLE served as the nucleus for early hacker culture at MIT.

Technical details

The instruction format consisted of a 5-bit basic operation code, a 1-bit indirect address bit, and a 12-bit memory address. If the indirect address bit was set in the indirect word, the indirection process repeated. The Program Counter is also 12 bits long.

The PDP-1 used one's complement arithmetic.

They were built out of DEC's System Building Blocks

External links