Seems the Arduino programming tool available through the #linuxmint app store was not what the Arduino people recommend.

I have the Arduino Nano producing data now. Honestly, most of my problems are crap software written by others!

divide float : 78.337 us
add float : 9.692 us
itoa() : 12.797 us
ltoa() : 125.387 us
dtostrf() : 76.687 us
random() : 90.537 us
y |= (1<<x) : 0.444 us
bitSet() : 0.444 us
analogReference() : 2.022 us
analogRead() : 112.937 us
analogWrite() PWM : 4.602 us
delay(1) : 1010.487 us
delay(100) : 99999.984 us
delayMicroseconds(2) : 0.759 us
delayMicroseconds(5) : 3.783 us
delayMicroseconds(100) : 99.537 us
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