NORD-10¶
The machine that made Norsk Data. Microprogrammed, paged, and built for real-time work.
| Introduced | 1973 |
| Type | Base machine |
| Word length | 16-bit |
| Needs a host? | No, runs on its own |
| Replaced | NORD-1 |
| Replaced by | ND-100 (1979) |
| Survivors | Several, including one at CERN in 1974 photographs |
The short version¶
The NORD-1's successor and ND's international breakthrough - this is the machine CERN bought. Where the NORD-1's control logic was wired in, the NORD-10's instructions are carried out by a microprogram in a small memory, which made the design cleaner and let ND add instructions without changing hardware. It gave each of its 16 interrupt levels a complete set of registers, so switching between tasks became a change of selection rather than a copy through memory.
Specification¶
| Item | Value |
|---|---|
| CPU | 24 printed circuit boards; last 8 rack slots for program-controlled I/O |
| Registers | 160 total - 8 general plus 2 microcode scratch on each of 16 levels; 128 visible to programs |
| Memory | 8K-word modules, up to eight per 19-inch rack |
| Address space | 64K words virtual, extended to 256K words physical by paging |
| Paging | 1024-word pages; 16-bit virtual mapped to 18-bit physical; four page tables of 64 words in fast registers |
| Protection | Per-page read/write/fetch bits and four rings (0 user, 1 compilers, 2 operating system, 3 kernel). Both must pass |
| Control store | 1K x 32 bits ROM. Four microinstruction types: ARITHMETIC, INTERBLOCK, JUMP, LOOP |
| Also in the ROM | Operator panel driver, MOPC operator communication, bootstrap loader, memory check |
| Interrupts | 16 levels, each with its own registers. Context switch 1.5 microseconds |
| Floating point | Standard, 48-bit. 32-bit format available as alternate microcode |
| Operating system | SINTRAN III, and NORD-TSS for timesharing |
What was new¶
- Microprogrammed control - ND said the NORD-1's 'large and complicated Time Counter/Cycle Counter' was hard to structure and understand.
- Registers per interrupt level, so a context switch stops copying anything.
- Hardware paging with a four-ring protection model on top of per-page bits.
- Customers could have their own instructions microprogrammed in.
Configurations¶
| Machine | What differs |
|---|---|
| NORD-10/S | Adds cache and improved paging (1975) |
| NORD-12 | Compact, cheaper, same instruction set and ROM |
| NORD-42 | OEM version of the NORD-12 for Norcontrol |
| NORD-50 | 32-bit array processor that attaches to a NORD-10/S |
Sources¶
- Primary:
Reference-Manuals/10/- ND-06.008.01 Reference Manual, ND-06.010.01 Microprogram, NORD-10-Design-Goals - Secondary: ndwiki NORD-10
Full context: MACHINE-TIMELINE.md.