> I'd like to have the A-157 itself with the same internal address bus, that

the A-154 is providing.

I think that's not possible because the rows are independent from each other
(because of the planned features like independent first/last step,
direction, clock, reset and so on). There is not ONE address bus for all
rows. Only in the very first controller version with all eight rows in
parallel from step 1...16 it should be possible to output the current
address on four port pins of the microcontroller.

> The final wish then is another extender A-155-2 that adds eight
> potentiometers/switches to an existing A-155 to provide 16 steps from
> one A-155. The actual solution with a second A-155 has various
> disadvantages (waste of space, influence of the amount controls,...).

This would require a redesign of the existing A-155 because in the existing
design (from 1997) one of the eight steps is always active. There is no
common "enable" for all steps available that turns off all 8 steps. But this
would be required for adding an extender module because the 8 steps have to
be turned off when the extender becomes active. That's why the A-154 has the
"A3" output available to switch between two units by means of an external VC
switch
Of course we are able to redesign the A-155 but this would help the owners
of the existing A-155.

Maybe it's a better idea to start a new sequencer subsystem with a master
controller (similar to the A-154) that outputs only the addresses and the
clock signal (required for the gating of the gate signals). CV and trigger
units can be then connected to this master controller.

Best wishes
Dieter Doepfer