The standard Lumatone mapping for Pythagorean-like scale systems has a C on the middle of the 5 keys sticking out the very left side of the keyboard, and the C major scale goes horizontally across the keyboard from there. The whole tone goes right-and-slightly-up and the diatonic semitone goes right-and-down, which implies that the apotome (the amount by which / alter pitches) goes up-and-slightly-right.
The name for this general kind of mapping is the Bosanquet-Wilson layout.
This mapping can be used without alteration for any rank-2 system whose period is an octave and whose generator is a (perhaps tempered) fourth or fifth. This includes Pythagorean, meantone, superpyth, helmholtz, etc.
A
B
B
C
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B
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G
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Not all notes with four or more flats are shown here; they follow the obvious pattern.
