CPU
The ND-100 line used a custom processor, and like the PDP-11 line, the CPU decided the name of the computer.
- Nord-100/CE, Commercial Extended, with decimal arithmetic instructions (The decimal instruction set was later renamed CX)
- ND-110, incrementally improved ND-100
- ND-110/CX, an ND-110 with the decimal instructions.
- ND-120/CX, completely redesigned.
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.
Read more about this topic: NORD-100