2023年9月25日 · New contenders, such as the Power PC, ARM and MIPS take the 68000 family’s place. Not really - also you forget the NS32k family going away at the same time, being maybe less visible but at least as successful as the 68k. I cannot find in the internet the reason why the 68000 family fell out of favor in the personal computer market.

The 68000 has instructions for reading or writing words (16 bits) and bytes. In the latter case, it needs to be able to tell the world which half of the databus it is reading or writing. According to the 68000 user manual (table 3-1), when the process is reading or writing the data bus the LDS and UDS signals are used to tell the world which ...

The 68000 family was clearly designed with an eye towards high-level language programming. The architecture was 32-bit in concept, although the original implementations were 16-bit. It had "flat" unsegmented memory addressing, which is always easier for compilers, and could address 16MiB of RAM, which increased to 4GiB in later members of the ...

2017年5月13日 · The 4 clock cycles per memory access was for instruction fetch and the 68000 could actually take longer. (Internal Architecture of 68000 was 3 16-bit Arithmetic Logic Units; 2 for Data registers and 1 for Address meaning that 32-bit addresses took longer to calculate.

2020年10月17日 · The 68000 and 68020 are sometimes used where interrupt latency is less of a concern. 3: Ability to run at "micropower", ie. less than a milliwatt, in embedded applications that demand extremely long battery life, sometimes on the order of several years (eg. 6502s are used in pacemakers). This practically demands a "fully static" CMOS ...

2019年7月18日 · Both MOVE.b MOVE.w are two-word instructions. The 68000 actually knows both words before either instruction begins, so both can occur pretty much immediately but both then require that a further two words be fetched to repopulate the instruction prefetch queue, which occupies eight cycles before the next instruction can begin.

2020年11月14日 · Motorola's 68000 was simply not ready at the time - and as well without second source (at the time) Zilog's Z8000 could have made it - except Zilog was (at that time) owned by Exxon, who at that time invested an extreme amount of money in what they perceived as a future without oil, creating Exxon Office System in direct competition to IBM in ...

2019年7月24日 · For an 8Mhz 68000, there are 8,000,000 clock cycles per second. A bus cycle is the complete set of states that describes a bus interaction — most normally a read or write, and usually 4 cycles / 8 states long.

2020年10月29日 · The 68000 was 16-bit externally but 32-bit internally: that is why the Atari machine that used it was called the ST, short for "sixteen/thirty-two". The first fully-32 bit 680x0 chip was the 68020 (1984). It was faster but did not offer a lot of new capabilities, and its successor the 68030 was more successful, partly because it integrated a ...

2024年10月8日 · 64-pin DIPs were available in the 80s: the Motorola 68000, introduced in 1979, came in a 64-pin DIP.When it was designed, this was pushing the envelope; quoting the Computer History Museum’s Oral History Panel on the Development and Promotion of the Motorola 68000: