I am having difficulty visualizing the stepping process.
The permutation of Wheel I
of Enigma I
is as follows:
ABCDEFGHIJKLMNOPQRSTUVWXYZ
EKMFLGDQVZNTOWYHXUSPAIBRCJ
For this rotor, the stepping notch is at Y
. The literature states that the letter Q
is visible when the notch is positioned, and after the step, R
is visible.
It is my current understanding that the lower (exit) row increments with every character entry (which would be represented here by a circular shift), and when it gets to the notch, a step of the next wheel occurs. My question is, what is the configuration of the lower row with respect to the upper rows at the notch step? If Y
is the final character in the lower (exit) row (26), then Q
is in position 19 in the upper row. Shouldn't it be at position 1? Or conversely, when Q
is in position 1, Y
is in position 8.
Are the notch sensor and window always 7 contacts apart (on this rotor), or are they both relative to some other component?
Can someone provide a diagram of where this rotor is prior to the step (i.e., notch Y
and window Q
)?