Can we finally end this Apollo computer comparison forever? It was a real time computer NOT designed for speed but real time operations.1

Why don't you compare it to let's say pdp11, vax780/11 or Cray 1 supercomputer?

NASA used a lot of supercomputers here on earth pior to mission start.

> It was a real time computer NOT designed for speed but real time operations.

More than anything, it was designed to be small and use little power.

But these little ARM Cortex M4F that we're comparing to are also designed for embedded, possibly hard-real-time operations. And dominant factors in experience on playback through earbuds are response time and jitter.

If the AGC could get a capsule to the moon doing hard real-time tasks (and spilling low priority tasks as necessary), a single STM32F405 with a Cortex M4F could do it better.

Actually, my team is going to fly a STM32F030 for minimal power management tasks-- but still hard real-time-- on a small satellite. Cortex-M0. It fits in 25 milliwatts vs 55W. We're clocked slow, but still exceed the throughput of the AGC by ~200-300x. Funnily enough, the amount of RAM is about the same as the AGC :D It's 70 cents in quantity, but we have to pay three whole dollars at quantity 1.

> NASA used a lot of supercomputers here on earth pior to mission start.

Fine, let's compare to the CDC 6600, the fastest computer of the late 60's. M4F @ 300MHz is a couple hundred single precision megaflops; CDC6600 was like 3 not-quite-double-precision megaflops. The hacky "double single precision" techniques have comparable precision-- figure that is probably about 10x slower on average, so each M4F could do about 20 CDC-6600 equivalent megaflops or is roughly 5-10x faster. The amount of RAM is about the same on this earbud.

His 486-25 -- if a DX model with the FPU -- was probably roughly twice as fast as the 6600 and probably had 4x the RAM, and used 2 orders of magnitude less power and massed 3 orders of magnitude less.

Control flow, integer math, etc, being much faster than that.

Just a few more pennies gets you a microcontroller with a double precision FPU, like a Cortex-M7F with the FPv4-SP-D16, which at 300MHz is good for maybe 60 double precision megaflops-- compared to the 6600, 20x faster and more precision.