Difference between revisions of "PDP-8/A"

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* DKC8-AA - front panel control, real-time [[clock]], [[asynchronous serial line]] interface, etc
 
* 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 uses [[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 two-word integers.
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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 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.

Revision as of 16:02, 4 September 2018


PDP-8/A
Year Introduced: 1976
Form Factor: minicomputer
Word Size: 12
Logic Type: TTL
Clock Speed: 333KHz
Memory Speed: 1.5 µseconds
Physical Address Size: 32KW (requires optional KM8-A)
Virtual Address Size: 4KW
Memory Management: bank selection, CPU mode
Bus Architecture: OMNIBUS
Operating System: OS/8, TSS/8
Predecessor(s): PDP-8/E


The PDP-8/A was DEC's last non-microprocessor PDP-8. The KK8-A CPU was a single hex board, which plugged into an OMNIBUS backplane. It supported both 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:

The FPP8/A used two hex boards; it was not part of the CPU, but used DMA for its instructions 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); 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.