Doepfer A-173-1/2 Micro Keyboard is a controller module for modular synthesizers in Eurorack format. The module is a combination of a vertical miniature keyboard with 1 1/2 octaves (A-173-1) and a corresponding receiver unit with 15 gate outputs, which follows the 1V/octave standard and supplies the corresponding (global) gate signal (A-173-2). To enable individual gate signals to be separated from the CV unit, the A-173-2 module has a kind of split function. For example, the CV unit can be used to transpose sequences without having to access an external midi keyboard. With up to 15 different gate signals, for example, start/stop functions can be triggered or envelopes triggered. The two module parts are connected via a 2-pole cable at the rear of the modules. This means that they do not necessarily have to be arranged next to each other.