A friend works for an airline as a flight simulator tech. Their entire software stack, including the compiler and OS, is FAA-certified.

Then their ancient Honeywell(?) mainframes reached end-of-life they scouted for compatible hardware, of which there was none. The cost of certifying new software, plus the time involved, was astronomical. So, after consulting with the FAA, they paid a hardware company to clone the ancient mainframes in modern silicon. The FAA signed off on it, and they had all-new computers - much smaller than the originals - running the old stack.

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zx8080 2 hours ago | parent | next [-]

It's _very_ hard to believe some company to simply "clone the mainframe" into chip. Mind sharing any link to this effort?

	▲	vincent-manis an hour ago \| parent [-]
		When Xerox established PARC, they asked the assembled scientists what computer they wanted. The majority view was a DEC PDP-10 KA10, with the BBN memory management unit that let it run Tenex (the ancestor of DEC TOPS-20). Xerox couldn't really buy a competitor's mainframe, so they built MAXC (maximum access computer), which was a complete emulation of the Tenex machines.

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betaby 2 hours ago | parent | prev [-]

That's interesting. That means there are fewer checks for hardware than software?

	▲	soulofmischief an hour ago \| parent [-]
		Hardware is more amenable to static analysis than running programs which may receive an arbitrary number of inputs and express an arbitrary number of possible intermediate states. I am interested in how firmware is treated, since perhaps in the case of these old machines it's small enough to be analyzable or at least cloned bit-for-bit.