Hacker News Reader

Yeah, I second that 16 bit or 16/32 was far more commonly used than 32, due to the 16 bit bus.

The bus always seemed like the oddest part to zero in on. By analogy, an Opteron in 2003 was a 64 bit CPU with a 32 bit HyperTransport bus, but no one called an Opteron system 32 bit. The width of a particular internal implementation detail is a strange duck IMO.

I think part of it was that to hardware companies the bus width is actually extremely important - the whole system is built around it, and the programming model the software guys work with less so.

And then the other part of it is the marketing angle: everyone knew full 32-bit inside and out chips were just on the horizon. Downplaying the 68k’s 32-bitness would give them a selling point for the 68020.

All ALU operations are also more expensive with 32 bit operands. So 16 bit data bus, 24 bit address bus. Slower arithmetic with 32 bit operands. I never though of it as a 32 bit CPU.

Reply on news.ycombinator.com