Bytecode VMs in surprising places (2024) • Hacker News Board

Re: Bytecode VMs in surprising places (2024)

#71

Post by BuildTheRobots » Tue, May 26, 2026, 2:21 PM UTC

mjg59 wrote: post #47

actionfromafar wrote: post #42

Earlier quoted context omitted.

Power Macs had an x86 emulator which ran the x86 ROM in PCI cards.

I don't think that's true? Macs were running Open Firmware, they had an expectation of the same Forth code that Suns made use of, and several cards needed to be flashed with Apple firmware to be Mac compatible. Alphas definitely ran x86 video card init code under emulation, though.

iirc, the OpenFirmware boot image was larger than the equivalent BIOS image - I've got half a memory of resoldering ROM chips on ATi cards so they could be cross-flashed to work in G3/G4 PoweMacs.

Re: Bytecode VMs in surprising places (2024)

#72

Post by indrora » Tue, May 26, 2026, 2:24 PM UTC

kurtoid wrote: post #58

LEGO Mindstorms programs run in an on-brick VM, iirc

Kinda-Sorta.

If you read Proudfoot's docs [ https://www.mralligator.com/rcx/ ] you'll find that what Lego did was half VM half native half "well, it depends".

There's a BIOS/stdlib, which in turn boots a userspace OS held in RAM ("firmware") that then executes the assembled mini-VM. However, there was nothing keeping people from rewriting the in-ram OS with something else, which led to BrickOS, jeJOS, pbForth, ROBOLAB, etc.

I spent many, MANY hours of my youth hacking on the RCX and am damn sad that there isn't currently a good replacement for it.

Re: Bytecode VMs in surprising places (2024)

#73

Post by qubex » Tue, May 26, 2026, 5:58 PM UTC

I’m old enough that I could do more computation on my father’s office’s laserwriter sending it postscript than I could on my Amstrad 1512.

Re: Bytecode VMs in surprising places (2024)

#74

Post by kurtoid » Tue, May 26, 2026, 8:16 PM UTC

indrora wrote: post #72

kurtoid wrote: post #58

LEGO Mindstorms programs run in an on-brick VM, iirc

Kinda-Sorta. If you read Proudfoot's docs [ https://www.mralligator.com/rcx/ ] you'll find that what Lego did was half VM half native half "well, it depends". There's a BIOS/stdlib, which in turn boots a userspace OS held in RAM ("firmware") that then executes the assembled mini-VM. However, there was nothing keeping people from rewriting the in-ram OS with something else, which led to BrickOS, jeJOS, pbForth, ROBOLA…

That's on RCX. I don't know for certain about the NXT 1 or 2, but the EV3's VM is called LMS2012