I will further mention that I have an implementation which gives rich debugging information for C programs. We're going to be releasing this over the next few months, and it should provide a lot more visibility into 6502 development than what most people are used to.

Would not it be better to split families to two subsets by range - defining format in future proof way? As it is currently defined, any tool written now has no way of supporting future families without recompilation.

I think that's a tautology. If you don't know the meaning of a future DWARF ...

Fixed, thank you.

This is fairly well-worn territory in computer science and mathematics, and I do not recommend reinventing the wheel.

https://en.wikipedia.org/wiki/Linear_congruential_generator
https://en.wikipedia.org/wiki/Linear-feedback_shift_register
https://en.wikipedia.org/wiki/Blum_Blum_Shub
https://en ...

Greetings all, it's Byrd from over at your friendly https://www.llvm-mos.org project. We've gotten our ELF specification more or less firmed up, at least to the point that the llvm-mos project is able to support a couple dozen targets with it. ELF, as you know, is an Executable and Linkable Format ...

Seems like a very fun project!

One of the difficult things, in any retro-engineering effort, is making the decision of how historically accurate you would like to be in your work. Do you want physical hardware, or is emulation enough? Is it legal to use modern tools and technologies, or must all ...

Since we're on the topic: we managed to port LLVM to the 65xx series of microprocessors, and LLVM has a fairly new flang compiler front-end built in nowadays. I imagine it would be an incremental amount of work to get the flang front-end working with our existing llvm-mos backend. https://www.llvm ...

Dear 65xx community:

We are in the early phases of implementing 65816 support as part of the https://www.llvm-mos.org project, and we need your opinons.

For those who aren't familiar with what LLVM-MOS is - LLVM-MOS is a fork of the LLVM toolchain (which includes a compiler, assembler, linker, and ...

I hate to sound like a broken record, but https://www.llvm-mos.org .

I tried adding some compiler options (-Oi -Os --codesize 999 --static-locals), with this result
https://godbolt.org/z/sds77vzcT

where
char sum(char a, b) {
char z;
z=a+b;
return z;
}


is transformed to
.proc _sum: near

L0002:

jsr pushax
ldy #$00
lda (sp),y
clc
ldy #$02
adc (sp),y ...

Linux is a first-class host for llvm-mos, and it supports 65c02 natively.
Wow! (or Gosh! or somesuch) : it looks a bit frightening at first... As I haven't yet created the customization files for my setup in cc65 , I'll try and do a comparison between the two environments. The big + for cc65 is ...

Linux is a first-class host for llvm-mos, and it supports 65c02 natively.

Here's a standards-compliant implementation. Only compiles on llvm-mos as far as I know.

https://github.com/rweather/berkeley-softfloat-3-6502

Someone has set up a livestream of Linux booting in real time on an actual C64: https://www.youtube.com/watch?v=g-36d07DfgI

EDIT: he's giving up at 12 hours. It will require approximately a week to boot Linux.

Necro'ing a dead thread just to demonstrate how common wisdom can be wrong. "But does it run Linux?" can now be finally and affirmatively answered for the 6502, running for example on the Commodore C64. It runs extremely slowly and it needs a RAM Expansion Unit (REU), as there is no chance to fit it ...