Difference between revisions of "PDP-8/L"
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* The -8/L used a positive I/0 bus, not negative  | * The -8/L used a positive I/0 bus, not negative  | ||
* The -8/L was not pre-wired for a number of devices  | * The -8/L was not pre-wired for a number of devices  | ||
| − | * The -8/L could not accomodate the Extended Arithmetic Element  | + | * The -8/L could not accomodate the [[Extended Arithmetic Element]]  | 
* The -8/L supported a maximum of 8KW of [[main memory]]  | * The -8/L supported a maximum of 8KW of [[main memory]]  | ||
| Line 35: | Line 35: | ||
* DW08-A Negative I/O Bus Interface, to allow use of older PDP-8 devices  | * DW08-A Negative I/O Bus Interface, to allow use of older PDP-8 devices  | ||
| − | * MC-8/L Memory Extension Control,   | + | * MC-8/L Memory Extension Control, [[bank switching]] needed to support more than 4K [[word]]s of memory  | 
| − | * MP-8/L Memory Parity  | + | * MP-8/L Memory [[Parity]]  | 
It could perform an addition to the [[accumulator]] in 3.2 µseconds, and a subtraction in 6.4 µseconds.  | It could perform an addition to the [[accumulator]] in 3.2 µseconds, and a subtraction in 6.4 µseconds.  | ||
| + | |||
| + | ==External links==  | ||
| + | |||
| + | * [http://www.bitsavers.org/pdf/dec/pdp8l PDP-8/L] - Original PDP-8/L documents  | ||
{{Nav PDP-8}}  | {{Nav PDP-8}}  | ||
[[Category: PDP-8s]]  | [[Category: PDP-8s]]  | ||
Revision as of 01:01, 16 May 2021
| PDP-8/L | |
|   PDP-8/L from an ICS Astrotype system  | |
| Year Introduced: | 1968 | 
|---|---|
| Form Factor: | minicomputer | 
| Word Size: | 12 | 
| Logic Type: | TTL | 
| Design Type: | clocked random logic | 
| Clock Speed: | 312KHz | 
| Memory Speed: | 1.6 µseconds | 
| Physical Address Size: | 8KW (requires optional MC-8/L) | 
| Virtual Address Size: | 4KW | 
| Memory Management: | none | 
| Bus Architecture: | positive logic I/O bus | 
| Operating System: | TSS/8 | 
| Predecessor(s): | PDP-8/I | 
| Successor(s): | PDP-8/E | 
The PDP-8/L was a effectively a cost-reduced version of the PDP-8/I in the PDP-8 line; it apparently had the same CPU as the -8/I.
The primary differences between the two are:
- The -8/L was slightly slower
 - The -8/L used a positive I/0 bus, not negative
 - The -8/L was not pre-wired for a number of devices
 - The -8/L could not accomodate the Extended Arithmetic Element
 - The -8/L supported a maximum of 8KW of main memory
 
Options for the -8/L included:
- DW08-A Negative I/O Bus Interface, to allow use of older PDP-8 devices
 - MC-8/L Memory Extension Control, bank switching needed to support more than 4K words of memory
 - MP-8/L Memory Parity
 
It could perform an addition to the accumulator in 3.2 µseconds, and a subtraction in 6.4 µseconds.
External links
- PDP-8/L - Original PDP-8/L documents
 
| 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  |