I'm probably Stockholm Syndrommed about 6502.  It's what I grew up on, and I still like it a great deal.  Admittedly register-starved (well, unless you consider the zero page a whole page of registers), but...simple, easy to fit in your head, kinda wonderful.

I'd love a 64-bit 6502-alike (but I'd probably give it more than three registers).  I mean given how little silicon (or how few FPGA gates) a reasonable version of that would take, might as well include 65C02 and 65816 cores in there too with some sort of mode-switching instruction.  Wouldn't a 6502ish with 64-bit wordsize and a 64-bit address bus be fun?  Throw in an onboard MMU and FPU too, I suppose, and then you could have a real system on it.

32-bit SPARC was kind of fun and felt kind of like 6502.  The 6502 wasn't exactly RISCy...but when working with RISC architectures, understanding the 6502 seemed to be helpful.

I really liked the 68000, but in a different way.  It's a nice, regular, easy-to-understand instruction set without many surprises, and felt to me like it had plenty of registers.  Once the 68030 brought the MMU onboard it was glorious.

Post-370 (which is to say 390/z IBM mainframe architectures) went wild with microprogrammed crazy baroque very, very special purpose instructions.  Which, I mean, OK, cool, I guess, but not elegant.

I don't really know enough about the DEC architectures.  It is my strong impression that the PDP-11 is regular, simple to understand, and rather delightful (like I find the 68000), while VAX gets super-baroque like later IBM mainframe instruction sets.  Although I've worked with emulated 10s, 11s, and VAXen, I've never really done anything in assembly (sure, you can argue that C is the best PDP-11 preprocessor there is) on them.

On Thu, Feb 4, 2021 at 3:12 PM Steve Nickolas <usotsuki@buric.co> wrote:
On Fri, 5 Feb 2021, Dave Horsfall wrote:

> The Z80 was quite nice; I wrote heaps of programs for it, and I even found an
> ANSI C Compiler for it (Hi-Tech as I recall; BDS-C was, well, you could
> barely call it "C")[*].  I compiled a number of Unix programs...

Well, it *was* "Braindead Software" C.


> The x86 architecture is utterly brain-dead; I mean, what's wrong with a
> linear address space?  I think it was JohnG who said "segment registers
> are for worms".

The 65816 doesn't have the screwed-up bitshifted segment stuff but it's
also a segmented architecture and is also braindead.

And I'm a 65C02 fan.