View source for PDP-8/A

{{Infobox Machine 
| name = PDP-8/A
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| image = PDP 8 e Trondheim.jpg
| caption = PDP-8/E front panel
| ram = Maximum of 32 kwords in eight 4 kword banks
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| year introduced = 1976
| form factor = [[minicomputer]]
| word size = 12
| physical address = 32KW (requires optional KM8-A)
| virtual address = 4KW
| logic type = [[Transistor-transistor logic|TTL]]
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| design type = [[clock]]ed random [[logic]]
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| clock speed = 333KHz
| memory speed = 1.5 µseconds
| bus arch = [[OMNIBUS]]
| memory mgmt = bank selection, CPU mode
| operating system = [[OS/8]], [[TSS/8]]
| predecessor = [[PDP-8/E]]
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| successor = [[]]
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}}

The '''PDP-8/A''' was [[Digital Equipment Corporation|DEC]]'s last non-[[microprocessor]] [[PDP-8]]. The KK8-A [[Central Processing Unit|CPU]] was a single [[DEC card form factor|hex]] board, which plugged into an [[OMNIBUS]] [[backplane]]. It supported both [[core memory|core]] [[main memory]] (MM8-AA and MM8-AB) and [[semiconductor]] (MS8-A).

There were a number of options available for use with the -8/A, including:

* KM8-A Extended Option - main memory extension and [[time-sharing]] control, etc
* FPP8/A Floating Point Processor
* DKC8-AA - front panel control, real-time [[clock]], [[asynchronous serial line]] interface, etc

The FPP8/A used two hex boards; it was not part of the CPU, but used [[Direct Memory Access|DMA]] for its [[instruction]]s and data. Its [[floating point]] format provided three and six [[word]] formats, with 12 bits of exponent; it also supported double-word integers.

The -8/A could use either an Operator's Panel, or a Programmer's Panel (similar to the [[KY11-LB Programmer's Console|KY11-LB]]); the latter required the DKC8-AA.

The -8/A came either as a kit of boards, or as a complete system including a chassis, [[power supply]] and backplane; in the latter form, there was a list of different configurations.

{{Nav PDP-8}}