ND-100¶
The workhorse. A whole 16-bit computer on one board, and ND's best seller.
| Introduced | 1979 (renamed from NORD-100 in 1978) |
| Type | Base machine |
| Word length | 16-bit |
| Needs a host? | No, runs on its own |
| Replaced | NORD-10/S |
| Replaced by | ND-110 (1985) |
| Survivors | 79 on the machine list (1 restoration, 6 dismantled, 72 unknown) |
The short version¶
It started as the NORD-10/M - M for Micro - a cheaper bit-sliced version of the NORD-10 meant for other manufacturers to build into their products. When the board was finished and tested it turned out to be far faster than the NORD-10/S, so the marketing was thrown away and it was sold as the successor instead. It runs the same SINTRAN III and the same programs as the NORD-10/S. Compact versions were still being delivered to customers in 2001.
Specification¶
| Item | Value |
|---|---|
| CPU | Single board. Bit-slice chips, each holding a 4-bit slice of the 16-bit ALU and register set, so four per machine |
| Memory management | Separate MMS card. CPU plus MMS drew 90 watts |
| Address space | 64K words on its own; 16M words (32 MB) with the memory management system |
| Control store | 2K x 64 bits microcode PROM |
| Writable control store | Optional, 256 words x 64 bits, for adding your own instructions |
| Cache | Macro-instruction cache |
| Speed | 150 ns minimum microinstruction cycle; at least 3 microinstructions per instruction |
| Interrupts | 16 levels, each with its own register set in a fast file on the CPU card. A context switch just selects another set |
| Addressing | Address arithmetic done in microcode, so the addressing structure could be changed by rewriting it |
| Slots | CPU in slot 2, MMS in slot 3. Slot 1 reserved for the Tracer, a hardware debugger |
| Operating system | SINTRAN III |
What was new¶
- The whole CPU on one board, combining as many as 16 boards from earlier generations.
- Bit-slice construction, which is what allows the instruction set to be changed in microcode.
- 16M words of physical memory with the MMS - 64 times the NORD-10.
- Compatible with the NORD-10/S, so existing customers kept their software.
Configurations¶
| Machine | What differs |
|---|---|
| ND-100/CE | Decimal and stack instructions, for commercial work |
| ND-100/CX | Improved CE plus MOVEW, TSET, RDUS and segment changes |
| ND-100 Compact | Small cabinet version |
| ND-100 Satellite | Small desk-side version |
Sources¶
- Primary:
Reference-Manuals/ND-06.014.2A EN ND-100 Reference Manual.md;ND-06.015.02 ND-100 Functional Description.md;ND-06.016.01 NORD-100 Input/Output System - Secondary: ndwiki ND-100, English Wikipedia
Full context: MACHINE-TIMELINE.md.