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At Lockheed in 2004, which had recently lost their bid on James Webb, some of us were trying to tell folks at Nasa about Lua. In all fairness, a lot of satellit

At Lockheed in 2004, which had recently lost their bid on James Webb, some of us were trying to tell folks at Nasa about Lua. In all fairness, a lot of satellites are running bizarre, one-off scripting languages created as needed. In the cases I know of, it was usually one junior engineer who made something without any spec. In the end they are always rigorously tested.

mfatica 7y ago
is there a Lua implementation for VxWorks? That seems to be the main constraint in their choice of language(s)
- whatshisface 7y ago
  Lua can be statically linked to anything written in C, because it's just a bunch of C code. That is one of the biggest reasons why it has seen such wide adoption. To quote their readme, >Building Lua should be straightforward because Lua is implemented in pure ANSI C and compiles unmodified in all known platforms that have an ANSI C compiler. [0] http://www.lua.org/manual/5.3/readme.html#install http://www.lua.org/manual/5.3/readme.html#install
- cptskippy 7y ago
  Yes. Canon's older Powershot series of cameras ran VxWorks, and if you're familiar with CHDK, Lua is one of the supported scripting languages.
Balgair 7y ago
Related: In Specialty Engineering, we had to irradiate the hell out of the CPUs and see what happened. This was done by running cables into the rad chambers and then running a program on the CPU to test all of the chips and other stuff on the motherboards as they were blasted. Most of the time, we just went up in dosage until the system failed, which wasn't long. One thing that always stuck out to me though, were the counters in the room. We'd leave one in the test chamber as close to the parts as possible, to get more accurate readings. Those little counters always borked out. The 7-part digital counters would just flicker and dance about in the rads. These 'hardened' counters would always fail first, and a lot sooner, than the CPUs. I was just doing the dosing, not the code in the CPU. But if those very simple counters were fried well before the more complicated CPUs, and they were not in the full thrust of the radiation, then I can't imagine what those guys were doing to mitigate their code in that rad-soup. It was very impressive.

mfatica 7y ago

is there a Lua implementation for VxWorks? That seems to be the main constraint in their choice of language(s)

whatshisface 7y ago
Lua can be statically linked to anything written in C, because it's just a bunch of C code. That is one of the biggest reasons why it has seen such wide adoption. To quote their readme, >Building Lua should be straightforward because Lua is implemented in pure ANSI C and compiles unmodified in all known platforms that have an ANSI C compiler. [0] http://www.lua.org/manual/5.3/readme.html#install http://www.lua.org/manual/5.3/readme.html#install
cptskippy 7y ago
Yes. Canon's older Powershot series of cameras ran VxWorks, and if you're familiar with CHDK, Lua is one of the supported scripting languages.

Balgair 7y ago

Related: In Specialty Engineering, we had to irradiate the hell out of the CPUs and see what happened. This was done by running cables into the rad chambers and then running a program on the CPU to test all of the chips and other stuff on the motherboards as they were blasted. Most of the time, we just went up in dosage until the system failed, which wasn't long. One thing that always stuck out to me though, were the counters in the room. We'd leave one in the test chamber as close to the parts as possible, to get more accurate readings. Those little counters always borked out. The 7-part digital counters would just flicker and dance about in the rads. These 'hardened' counters would always fail first, and a lot sooner, than the CPUs. I was just doing the dosing, not the code in the CPU. But if those very simple counters were fried well before the more complicated CPUs, and they were not in the full thrust of the radiation, then I can't imagine what those guys were doing to mitigate their code in that rad-soup. It was very impressive.