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amiga386yesterday at 8:55 PM2 repliesview on HN

While the 68000's registers are 32-bit, the data bus is 16 bit, the A1000, A2000 and A500 that defined the range had 16-bit fetching chipsets, they literally had 24-bit address buses. None of this says "32-bit". It can't be overlooked.

Many games crashed on the 32-bit clean A3000, A1200, A600, A4000 because programmers used the upper byte of addresses for their IQ or whatever. (Similar issues with ARM2 to ARM3 in Acorns, even RISC OS itself can be categorized into '26-bit' and '32-bit clean' varieties due to Acorn thinking the memory space ignores the upper 6 bits so they can store what they like there)

The competition before the Amiga's launch solidly called itself "8-bit". The next generation called itself "16-bit" to hype itself. Later machines touted their "32-bit"ness, and then came the Nintendo 64 and PSX on MIPS processors...

All the hedges you made, "don't look here, look there" can be reversed to emphasize the 16-bitness!

Does this say something about you? Did you come to the Amiga later in its life, e.g. 1991-1993, when 68020s/030s/040s were an option? Or were you there in 1985 when it debuted?


Replies

kstrauseryesterday at 11:21 PM

The Opteron had a 32 bit HyperTransport bus. Modern CPUs only implement 48 address lines. And yet we’d call all of those 64 bit systems. We wouldn’t call them 32 bit systems, and surely not 48 bit.

The 68k’s ISA is 32 bit through and through, however the underlying implementation looks. It did since I bought my A1000, marketed as a 32 bit system, in 1985.

show 1 reply
icedchaiyesterday at 10:46 PM

I can see it both ways.

I remember the Amiga always being compared to other "16-bit" machines, like the Apple IIgs, Atari ST, and early Macs.

I also remember the 68000 being referred to as 16/32-bit. Still, from a programmer perspective, the 68000 looked like a 32-bit machine, similar to what Intel did with the 386DX and SX.