Difference between revisions of "PDP-8/S"
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(Add image of front panel inlay) |
(see "Computer Structures: Readings and Examples", page 120: "A PDP-S/S is one-fifteenth of a PDP-8 at one-half the cost. ...even though the same 2-megahertz logic clock is used in both cases.") |
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| Line 9: | Line 9: | ||
| year discontinued = 1970 | | year discontinued = 1970 | ||
| architecture = [[PDP-8 architecture|PDP-8]] | | architecture = [[PDP-8 architecture|PDP-8]] | ||
| − | | physical address = | + | | physical address = 32k words (requires optional MC8S) |
| − | | virtual address = | + | | virtual address = 4k words |
| design type = [[clock]]ed random [[logic]] | | design type = [[clock]]ed random [[logic]] | ||
| − | | clock speed = | + | | clock speed = 2 MHz |
| memory speed = 8 μseconds | | memory speed = 8 μseconds | ||
| memory mgmt = bank select | | memory mgmt = bank select | ||
| Line 39: | Line 39: | ||
* DB8S Data Break, needed for data break on the I/O bus | * DB8S Data Break, needed for data break on the I/O bus | ||
| − | * MC8S Memory Extension Control, which was needed to support more than | + | * MC8S Memory Extension Control, which was needed to support more than 4k [[word]]s of memory |
* MM8S Memory Module | * MM8S Memory Module | ||
* ME8S Memory Extension, holds two MM8S | * ME8S Memory Extension, holds two MM8S | ||
Revision as of 19:35, 18 August 2019
| PDP-8/S | |
 PDP-8/S front panel inlay | |
| Manufacturer: | DEC |
|---|---|
| Architecture: | PDP-8 |
| Year Introduced: | 1967 |
| Year Discontinued: | 1970 |
| Form Factor: | minicomputer |
| Word Size: | 12 bits |
| Logic Type: | DTL |
| Design Type: | clocked random logic |
| Clock Speed: | 2 MHz |
| Memory Speed: | 8 μseconds |
| Physical Address Size: | 32k words (requires optional MC8S) |
| Virtual Address Size: | 4k words |
| Memory Management: | bank select |
| Bus Architecture: | Negative I/O Bus |
| Predecessor(s): | PDP-8 |
| Successor(s): | PDP-8/L |
The PDP-8/S was DEC's attempt to produce a 'cheaper' PDP-8. It was a serial implementation, which reduced the part count somewhat, but resulted in an incredibly slow machine, compared to the rest of the line. It was soon discontinued.
The PDP-8 was constructed with discrete transistors, packaged into DEC's FLIP CHIP technology. It could perform an addition to the accumulator in 64 μseconds. It had parity on the main memory as standard, not optional.
Options
Options included:
- DB8S Data Break, needed for data break on the I/O bus
- MC8S Memory Extension Control, which was needed to support more than 4k words of memory
- MM8S Memory Module
- ME8S Memory Extension, holds two MM8S
| v • d • e PDP-8 Computers, Software and Peripherals |
|---|
| PDP-8s: PDP-5 • PDP-8 • LINC-8 • PDP-8/S • PDP-8/I • PDP-8/L • PDP-12 • PDP-8/E • PDP-8/F • PDP-8/M • PDP-8/A
Workstations: VT78 Also: PDP-8 family • PDP-8 architecture • PDP-8 Memory Extension units |
