NORD-1¶
Norsk Data's first machine, and the first computer built commercially in Norway.
| Introduced | 1968 |
| Type | Base machine |
| Word length | 16-bit |
| Needs a host? | No, runs on its own |
| Replaced | - |
| Replaced by | NORD-10 (1973) |
| Survivors | At least 11, including serials 2, 4, 5, 37 and 47 |
The short version¶
A 16-bit minicomputer built from the then brand-new 7400-series TTL chips, at a time when most machines were still made of discrete transistors. It had hardware floating point as standard and, from 1969, optional hardware paging - so a program could be written for more memory than the machine physically had. Roughly 142 were built. The first one sold went into a ship's anti-collision system.
Specification¶
| Item | Value |
|---|---|
| CPU | Two racks, 64 cards, over 1,300 TTL chips. No microcode - control logic is hardwired |
| Memory | Ferrite core, 4K to 64K words. Fastest usable cycle 1 microsecond |
| Address space | 64K words. Optional paging gives 64K virtual in 256-word pages |
| Control store | None - hardwired |
| Cache | None |
| Interrupts | 16 levels (0-15). Registers saved and restored through core: max 38 cycles, 45 microseconds |
| Floating point | Standard. 48-bit, in three memory words. Accumulator is T:A:D |
| Registers | 8 general (R, A, D, T, L, X, B, P) plus 6 status flip-flops |
| Operating system | SINTRAN II (real-time) or NORD-TSS (timesharing), from 1971 |
| Physical | Cabinet with power supply, memory, CPU, I/O, power panel and fan box |
What was new¶
- One of the first computers built from integrated circuits rather than transistors.
- Hardware floating point as standard, which was unusual for a minicomputer.
- Hardware demand paging, documented by February 1970 - a real virtual memory system.
- Memory protection with a 16-bit register, one flag per memory block.
- Two CPUs could share one memory block.
Configurations¶
| Machine | What differs |
|---|---|
| NORD-2B | Simplified and cheaper version of the same design |
| NORD-5 | 32-bit compute module that attaches to a NORD-1 |
Sources¶
- Primary: NORD-1 Reference Manual (Feb 1970); ND-01.004.01 Hardware Manual
vols I and II; ND-01.005.01 Connectors - all in
Reference-Manuals/1/ - Secondary: ndwiki NORD-1, CPU detail, boards, serial 47
- Long form: ../NORD-1.md - the full chapter, with open questions
Full context: MACHINE-TIMELINE.md.