Fine tuning the Ensoniq Mirage

Hello, I’ve acquired an Ensoniq Mirage DSK-8 and I’m trying to suss it out. The fine tuning has me stumped. I know the MASOS guide says each fine tune step is 256th of an octave, but what hex value represents an untuned sample please? The default values on ‘blank formatted diskettes’ are FA for lower memory and 8E for upper memory. This gives playback at ‘unity rate’ on an E (lower keyboard) and A (upper keyboard) when sampling at default sample rate.

A MASOS guide example (page 20) suggests 40 hex steps would take you down a quarter octave (minor third) in the upper keyboard, but I think there follows a typo as it suggests lowering the fine tune value from 84-44. This is way more than 40 hex steps and no explanation as to why it would be at 84 in the first place!

An example in the MASOS guide (page 37) suggests tuning it down a half octave (perfect 5th) from an E to an A in the lower half requires a hex value of 80. As 80 is half way in a hex table of 256, this suggests FF (highest value) is untuned.

Finally, 80 seems to be a suggested default for samples with short loops where the source is detuned appropriately instead which confuses things further.

I love this beast but it’s a puzzle! Would also be great to have a chart showing the playback rate associated with each key. Can any Syntaur genius shed some light for me please? Much appreciated.