Thread: 68k details
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Old 19 August 2018, 23:25   #25
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Originally Posted by frank_b View Post
How far can you conditionally branch in a 68k vs an 8086? It's +-32k on the 68k vs +-127 bytes (yikes) on the 8086.
Fixed in 1982 but yes.

Here are some other interesting questions.

How many registers do you have on the 8086? How many of them can be used for any operation? How many addressing modes do you have? What's the maximum word size you can use? What's the maximum addressing range? How many bits can you shift in a single instruction?
Counting registers how exactly? 8+4 I'd say.

None. For instance instructions like MOVS*, SCAS*, STOS* use fixed registers. The 8086 is a modified accumulator architecture after all.

Depends on how one counts address modes, is the STOS* instruction an address mode for instance? Not many, I'd say 5.

16 bit of course, it's a 16 bit processor. It does however support some 32 bit operations.

1MiB or 64KiB depending on what you mean.

255(!) - most of those are a waste of time of course. Later x86 limits this, one of the few incompatibilities in the series.

The 8086 is a toy in comparison to the 68k. Like a z80 with delusions of grandeur. You can't compare them. The 68k is superior in every single way.
Nope. Not in price nor complexity. While the 68000 was selected for expensive workstations the 8086 was selected for the IBM PC. The rest is history.
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