The Kenton GPMX-16 has 16 GPI (general purpose interface) inputs and 16 GPI outputs arranged on four 9 pin D connectors. D sockets for inputs and D plugs for outputs. It can receive and output MIDI messages as Notes, Controllers (CCs) or Program Changes. In the following description references to MIDI note numbers also applies to Controller Numbers or Program Numbers if that is the input or output mode currently in use.

Features
The Kenton GPMX-16 has 16 GPI (general purpose interface) inputs and 16 GPI outputs arranged on four 9 pin D connectors. D sockets for inputs and D plugs for outputs.

Each block of 8 inputs and outputs can be assigned a starting MIDI note number and subsequent inputs and outputs follow on consecutive note numbers. Default for the first block is 36 – 43 and for the second 44 – 51.

MIDI channels can be set independently for inputs and outputs. Default channels – transmit = 1 receive = 2
The debounce value for all switch inputs can be set (range 1 to 100 milliseconds – default 10mS)

The inputs are arranged with internal pull-ups, so that shorting an input to ground will send the appropriate MIDI ON message – releasing the short to ground will send a MIDI OFF message (unless disabled)

GPI outputs can be pulsed (default) or controlled with on & off messages

GPI outputs are floating and can each switch up to 50 Volts at 100mA of resistive load

Pins 1 – 8 are the output pins and pin 9 is the common connection. Pin 9 can be + or – relative to pins 1 to 8

There are two MIDI output sockets which both carry identical MIDI information. MIDI arriving at the MIDI input is merged with the data generated by the switch inputs and sent to the MIDI outs

The unit is powered by an external multi-region power supply connected by a locking plug (included)

Editing of parameters is achieved by use of push buttons in conjunction with the LED display

Settings are stored in non-volatile memory. In order that settings cannot be accidentally changed, edit mode has to be enabled by the use of a recessed push button