4 ms·

I guess I'd expect that it could be virtualized. Or, at the very least, that the hardware-specific API was somewhat-generalized or at least generalizable, so t

I guess I'd expect that it could be virtualized. Or, at the very least, that the hardware-specific API was somewhat-generalized or at least generalizable, so that it could be updated or used via a VM with a similar (even if dated) piece of hardware. Is it a lack of familiarity and developers for the code, or is it just not well-engineered? At those dollar amounts, it seems like any proven-solved "problem" is solvable again, likely "easier" due to the technology improvements...

amluto 10y ago
Ha! This stuff is old enough it might need real mode with the A20 gate. Intel, in a rare fit of backwards incompatibility, removed the A20 gate a while back. EPT might be able to emulate it, but that assumes a hypervisor author tried. And how are you going to plug that bespoke adapter into a modern system? CardBus? EISA? Who knows?
- digi_owl 10y ago
  Yeah i recall reading about some particle sensor at a university lab that was running on some ancient DOS beast because anything newer would throw some timings off. Never mind that the manufacturer was long gone, new sensor would be expensive, and the lab would have to suspend all experiments up to a year while running a series of baseline stuff to align old and new results.
woodman 10y ago
I had to buy a very old laptop because the software for configuring Motorola sabers depended on the cpu for timing communication with the radio during the flash process. People have bricked their radios trying to emulate old clock speeds. I'd hope that they'd have a more robust protocol in expensive aerospace platforms, but I wouldn't be surprised if that wasn't the case.
cnvogel 10y ago
In these days, a proper API would have been a .sys driver loaded in config.sys, or a TSR (terminate but stay resident) program leaving some routines in memory, hooking a software interrupt as the entry point. The (even then) ancient laboratory equipment I used in the 2000s, and often moved to more modern machines, never did this. It was all monolithic applications directly talking to parallel ports (port read/write to 0x378) or to memory mapped on the ISA bus. On the other hand, most stuff came with schematics, and from this most of the logic (short of a few PALs with blindingly obvious functionality) could be deduced. It all was quite simple stuff. But as long as hardware is still available (as are the Compaq computers in the article) investing the time isn't worth it. Would I have to do this today, I'd probably run the applications in DOSbox, add a emulation of the old hardware to the emulator, and pass the commands via USB or Network to a FTDI USB to something chip. Or to a BeagleBone/Raspberry/... with its GPIOs connected to the real hardware (mind the 5V levels). Unrelated to software running on old PCs, here's a guy who replaces the old CPU in the lab equipment with an embedded board running an emulated version of the original software: http://www.jks.com/5370/5370.html http://www.jks.com/5370/5370.html
PaulRobinson 10y ago
Do you seriously think virtualisation was a thing in the 1980s when the B-2 was being designed and built? It wasn't even a thing when the F-35 was being designed and initially built. It will be single-threaded apps running natively and talking directly to various bus adapters. The most advanced processor available to them was a M68020, maybe. Multi-tasking was still hard, Linux and Windows 3.0 were still a decade away when the systems engineers were designing the B-2. And that's assuming they were able to change the hardware platform in the 1980s - the designs would have been drawn up in the 1970s. There is absolutely no way on Earth that anybody would have thought "what we need here is a VM". I'd be amazed if it even had a Hardware Abstraction Layer, and that had a bit of historical form, albeit not in real-time operating systems yet.
- gaius 10y ago
  The '020 was Popek-Goldberg compliant at least! Good chip.
- woodman 10y ago
  It certainly was a thing in the 80s, IBM was selling it in the late 60s. [0] I don't know how difficult it would have been to put in an airframe though... I'm guessing: very. [0] https://en.wikipedia.org/wiki/Virtual_machines#History https://en.wikipedia.org/wiki/Virtual_machines#History
- barrkel 10y ago
  The first commercial computers were not PCs. You sound like you don't know anything about the history of computing. Almost every system technology we use was invented in the 60s and 70s.
  - PaulRobinson 10y ago
    You think they were sticking mainframes into the B-2?

amluto 10y ago

Ha! This stuff is old enough it might need real mode with the A20 gate. Intel, in a rare fit of backwards incompatibility, removed the A20 gate a while back. EPT might be able to emulate it, but that assumes a hypervisor author tried. And how are you going to plug that bespoke adapter into a modern system? CardBus? EISA? Who knows?

digi_owl 10y ago
Yeah i recall reading about some particle sensor at a university lab that was running on some ancient DOS beast because anything newer would throw some timings off. Never mind that the manufacturer was long gone, new sensor would be expensive, and the lab would have to suspend all experiments up to a year while running a series of baseline stuff to align old and new results.

woodman 10y ago

I had to buy a very old laptop because the software for configuring Motorola sabers depended on the cpu for timing communication with the radio during the flash process. People have bricked their radios trying to emulate old clock speeds. I'd hope that they'd have a more robust protocol in expensive aerospace platforms, but I wouldn't be surprised if that wasn't the case.

cnvogel 10y ago

In these days, a proper API would have been a .sys driver loaded in config.sys, or a TSR (terminate but stay resident) program leaving some routines in memory, hooking a software interrupt as the entry point. The (even then) ancient laboratory equipment I used in the 2000s, and often moved to more modern machines, never did this. It was all monolithic applications directly talking to parallel ports (port read/write to 0x378) or to memory mapped on the ISA bus. On the other hand, most stuff came with schematics, and from this most of the logic (short of a few PALs with blindingly obvious functionality) could be deduced. It all was quite simple stuff. But as long as hardware is still available (as are the Compaq computers in the article) investing the time isn't worth it. Would I have to do this today, I'd probably run the applications in DOSbox, add a emulation of the old hardware to the emulator, and pass the commands via USB or Network to a FTDI USB to something chip. Or to a BeagleBone/Raspberry/... with its GPIOs connected to the real hardware (mind the 5V levels). Unrelated to software running on old PCs, here's a guy who replaces the old CPU in the lab equipment with an embedded board running an emulated version of the original software: http://www.jks.com/5370/5370.html http://www.jks.com/5370/5370.html

PaulRobinson 10y ago

Do you seriously think virtualisation was a thing in the 1980s when the B-2 was being designed and built? It wasn't even a thing when the F-35 was being designed and initially built. It will be single-threaded apps running natively and talking directly to various bus adapters. The most advanced processor available to them was a M68020, maybe. Multi-tasking was still hard, Linux and Windows 3.0 were still a decade away when the systems engineers were designing the B-2. And that's assuming they were able to change the hardware platform in the 1980s - the designs would have been drawn up in the 1970s. There is absolutely no way on Earth that anybody would have thought "what we need here is a VM". I'd be amazed if it even had a Hardware Abstraction Layer, and that had a bit of historical form, albeit not in real-time operating systems yet.

gaius 10y ago
The '020 was Popek-Goldberg compliant at least! Good chip.
woodman 10y ago
It certainly was a thing in the 80s, IBM was selling it in the late 60s. [0] I don't know how difficult it would have been to put in an airframe though... I'm guessing: very. [0] https://en.wikipedia.org/wiki/Virtual_machines#History https://en.wikipedia.org/wiki/Virtual_machines#History
barrkel 10y ago
The first commercial computers were not PCs. You sound like you don't know anything about the history of computing. Almost every system technology we use was invented in the 60s and 70s.
- PaulRobinson 10y ago
  You think they were sticking mainframes into the B-2?