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At one of the Microsoft company meetings in the middle to late 2000s (I recall it was at Safeco Field) he claimed that when IBM was developing the PC he tried to convince them to use an MC68000 instead of the 8088. He said going with the 8088 set the industry back ten years. Assuming he wasn't making the story up, it's hard to imagine him making that quote or even agreeing with it.

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> He said going with the 8088 set the industry back ten years.

That's what it always felt like as an Amiga user. Not before DOOM there was much I liked on the PC.

Release Amiga 1000: July '85 Release DOOM: December '94

I saw an Amiga once in person around 86 and spent that next decade disappointed, but advocating that the future of computing was going to be great. Emotionally I still feel like we haven't caught up to the Amiga but I imagine that isn't really true, heh.

Similar story with me. I got an Amiga 1000 and did a fair bit of assembly coding on it, then ended up writing some 16-bit x86 assembly for school later on. Being used to having sixteen 32-bit registers, then all the sudden having to use AX, BX, CX, and DX (and don't forget they all have slightly different purposes!) was like being brutally shoved back into the 80's.

Well, history has shown neither RISC nor CISC as actually a better choice, since both models more or less converged to a sort of hybrid design years ago.

And what this has to do with Amiga?

At a simplistic level, the difference between RISC and CISC processor design boils down to having many registers and reduced instructions, or few registers and extra specialized instructions.

What was being described is going to programming from a RISC-like design processor to a CISC-like design processor, and how they felt constrained after doing so. It likely does feel more constraining (I don't really remember how I felt about it back when I did it, but I also went the other direction, and only in the context of classwork), but in the end, most people are programming a level removed from that anyways.

There used to be quite a lot of arguments about what design was better (IMO mostly fueled by Macs running a RISC processor and Windows running a CISC processor, at least until Apple switched to x86). I find it slightly comical that both designs ended up in a fairly similar place though (with RISC processors adding extra instructions, and CISC processors adding more registers, even if mostly just logical registers).

All of them: IBM PC, Amiga and classic Mac were using CISC CPUs...

You're right that the Amiga was CISC, I was mistaken there.

The Classic Mac was as well, but PowerPC based macs were RISC, which is what I was recalling in my followup.

And seriously, who thought that "MOV A B" actually means "A = B" was a good idea?

68000 has it right!

I must have been 12 or 13 years old when I first met an IBM PC. I was used to 8 bit micros having BASIC right away (and colour). But you couldn't do anything with a PC before using two floppies. First DOS then whatever. It just seemed awful. Why would anyone want one of those?

I was used to all the 8 bit machines and their graphics and sound too, but I was enthralled by 80 column BASIC and DOS with its hierarchal file system as well. I saw it as a separate branch of computing entirely.

And once EGA came out, it quickly started to surpass the 8 bits as a gaming platform too.

That's not correct. If you don't have a floppy disk, the PC boots into ROM BASIC just like the 8-bit home computers of the time.

Here's the thing though. Engineering workstations existed. There's a good argument that the "right" approach was to use an MC68K and, while you were at it, a "real" operating system whether a Unix or one of the 16-bit operating systems in use on minicomputers at the time. But there's also a good argument that, had you done a more open and mass market-oriented engineering workstation (whatever that meant exactly) at, what?, 2x the price point of an IBM PC--which, remember, didn't even always have a hard disk at the time--you'd not have been competitive with Z80 or 6502 machines.

Even using the 8088 vs. the 8086 was a cost-saving move. A premium IBM PC might well have simply flopped rather than accelerating the industry.

It's not clear to me that at the time the m68k was that much more expensive than x86. It certainly was not by 84/85 when the Atari ST was shipping as a sub-$1000 cheap home computer based around it.

I think the bigger compelling piece for x86 was its continuity with the top-selling 8080/Z80 CP/M machines that were the effective standard at the time. IBM offered both PC-DOS (cheap) and CP/M (expensive), and wasn't sure which was going to win out. And PC-DOS was basically a kind of clone of CP/M, down to the API call names.

There was also the fact that the IBM people working on the original PC had already established familiarity with Intel's architecture through their work on an earlier IBM product, the Datamaster (http://www.oldcomputers.net/ibm5322.html), which used the 8-bit Intel 8085.

David J. Bradley (https://en.wikipedia.org/wiki/David_Bradley_(engineer)) worked on both the Datamaster and the PC projects, and explained the reasoning behind the choice of the 8088 for the latter in an article in the September 1990 issue of Byte (https://archive.org/stream/byte-magazine-1990-09/1990_09_BYT...):

There were a number of reasons why we chose the Intel 8088 as the IBM PC's central processor.

1. The 64K-byte address limit had to be overcome. This requirement meant that we had to use a 16-bit microprocessor.

2. The processor and its peripherals had to be available immediately. There was no time for new LSI chip development, and manufacturing lead times meant that quantities had to be available right away.

3. We couldn't afford a long learning period; we had to use technology we were familiar with. And we needed a rich set of support chips -- we wanted a system with a DMA controller, an interrupt controller, timers, and parallel ports.

4. There had to be both an operating system and applications software available for the processor.

Points 1 and 3 both reference lessons learned from the Datamaster project -- #1 is about the desire for the PC to overcome a limitation the Datamaster's 8-bit CPU had imposed on it, and #3 refers to the fact that the 8086 and 8088 were close cousins of the 8085, so the IBMers wouldn't have to learn a whole new architecture from scratch.

It's not hard to imagine the decision coming down to Bradley (or someone else on the Entry Systems Division team) calling someone they knew at Intel and saying "we need a 16-bit processor as similar to the 8085 as possible that you can deliver in volume tomorrow. Whatcha got?"

Point #4 would definitely have been a concern for the m68k as well. DR's CPM/68k wasn't AFAIK available yet (came a few years later), and Unix would have been expensive and too heavy weight.

They only offered CP/M after Kildal threatened a lawsuit, and at 3x the price. I think it was fairly certain which would win by IBM. That and DOS was mostly compatible, famously porting Visicalc only required changing 3 bytes.

This could be apocryphal (there was free beer at the company meeting), but I think I recall he (Gates) mentioned at the time that the existence of a solid chipset to support the 8088 was something that drove the ultimate decision.

It was not (or not just) for cost-saving reasons. It was due to a cross-licensing agreement between Intel and IBM for technology called Bubble Memory which turned out to be flop, but IBM didn't know at the time that it would flop.

"Next came the 8088, the processor for the first IBM PC. Even though IBM engineers at the time wanted to use the Motorola 68000 in the PC, the company already had the rights to produce the 8086 line (by trading rights to Intel for its bubble memory)"

https://www.ibm.com/developerworks/library/pa-microhist/inde...

Note that IBM introduced a 68000 machine just over a month before the PC came out, which caused some confusion at that time.

http://www.old-computers.com/museum/computer.asp?st=1&c=623

But 1981 was just too early for 68000 non workstation machines since the early chips were slow and expensive. The 1983 Lisa was limited to 4MHz, for example, in contrast to the 1984 Macintosh's 8MHz. I remember the price of the chips dropping from over $100 to less than $20 in just one year back then.

This I can believe. It's reasonably well known that the first PC design was deliberately crippled in order not to impact on sales of the dedicated word processor, the IBM Displaywriter.

The 8086 was thought too powerful and would compete against existing IBM products, so the 8088 was chosen. Other changes to expansion and bus architecture were on the same basis.

I spent over a decade completely failing to understand how it could succeed against Amiga.

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