ND-100

The Nord-100 was a 16-bit minicomputer series made by Norsk Data, introduced in 1979. It shipped with the Sintran III operating system, and the architecture was based on, and backwards compatible with, the Nord-10 line.

The Nord-100 was originally named the Nord-10/M (M for Micro) as a bitsliced OEM processor. The board was laid out and finished and tested when they realized that the CPU was far faster than the Nord-10/S. The result was that all the marketing material for the new NORD-10/M was discarded, the board was rechristened the Nord-100, and extensively advertised as the successor of the Nord-10 line. Later, in an effort to internationalize their line, the machine was renamed ND-100.

The ND-100 line used a custom processor, and like the PDP-11 line, the CPU decided the name of the computer.

The ND-100 line was machine-instruction compatible with the Nord-10 line, except for some "extended instructions", all in supervisor mode, mostly used by the operating system. Like most processors of its time, the native bit grouping was octal, despite the 16-bit word length.

The ND-100 series had a microcoded central processing unit, with downloadable microcode, and was considered a CISC processor.

The ND-100 was implemented using medium-scale integration (MSI) logic and bit-slice processors.

The ND-100 was frequently sold together with a memory management card, the MMS. The combined power use of these boards was 90 watts. These boards would usually occupy slots 2 and 3, for the CPU and MMS, respectively. Slot 1 was reserved for the Tracer, a hardware debugger system.

The CE stood for Commercial Extended. The processor was upgraded by replacing the microcode PROM.

It added instruction for decimal arithmetic and conversion, stack instructions, segment-change instructions used by the OS, a block move, test-and-set, and a read-without-cache instruction.

The ND-110 was an incremental improvement over the ND-100.

The ND-110 combined the Memory Management System and CPU, previously separate cards, on one board. The single CPU/MMS board was plugged into the memory management board slot, usually numbered 3. The power consumption was reduced from 90 watts to 60.

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