VBA
If you can emulate ARM 1 in 808 lines of BBC Basic, why not?
From the department of "but… why?" comes news of Linux running in Microsoft Excel, although all might not be as it seems. There are various painful ways to run Excel on Linux – using a web-version in Edge, a Windows virtual machine, or with WINE, say – but going the other way around and getting the Linux kernel to run in Excel …
The first time I saw Excel it launched from DOS and brought in its own private Windows 2 runtime.
Yep, definitely disappointing that this effort doesn't emulate a system in VBA, which is surely possible, though there are definitely hoops to negotiate, like the lack of unsigned integers and bit-shifting operations. I wonder which is the simplest Linux-compatible ISA to emulate?
-A.
By a strange coincidence, 808 is about the same number of lines of C-64 basic I used to write a 6502 assembler. I also had to write a simple EDLIN style text editor as the C-64 didn't have any capability to edit plain text files. I did all of this because as a broke teenager, I couldn't afford the $35 macro assembler cartridge.
a single humungous excel formula (function)† the encompasses the Linux virtual machine (mostly the syscall interface I would imagine) is magnificently insane. In size I imagine would have to be very many orders of magnitude greater than the largest LLMs.
Even the less Olympian approach of emulating the execution of a Linux kernel in excel using a minimal processor (also emulated) demonstrates if not a limited grip on sanity, a need to get out more.
† Probably the same problem as specifying the denotational semantics of a Linux kernel.
I imagine it would take an emulation of the simplest ISA that Linux supports (RISC V perhaps ?) alongside with memory and non-volatile storage.
No, I do not want to troubleshoot that spreadsheet either. In fact I do not want to see it. It's for the best if it's never created.
I'm holding out for someone to implement a world wide flying pigeon CPU where messages are sent, received and interpreted by pigeons.
Oh, wait,... a message passing operating system... that must be Hurd hurting the flying pigeons. At least they both will finish in about the same time.
Yes, that was the thought.
But QoS is not required on simple CPUspigeons, so using RFC1149 as a basis will suffice (as BLUG showed).
a message passing operating system
We wrote one of those over 40 years ago at Uni, back when degrees were in Computing, not IT, and taught low level programming. It was a group project in teams of four, and I suspect as much time was spent on inventing names* for the resulting O/S's as on writing them! I can't say I've ever felt the need to do this again but it gave us a deeper understanding of the background to both the O/S and the hardware and has certainly helped when developing multi-threaded applications**.
*Ours ended up as Group Operating System Supporting Advanced Message Exchange Routines. of GOSSAMER, largely because it hung by a thread!
**Nothing to do with work, model railway control on a Raspberry Pi.