There isn’t a way to do this with the onboard foot switches of the H90. However, it is possible to do this using an external 3-button aux switch connected to the EXP input of the H90. If we enter the System Menu and select MIDI, the third setting on the first page of controls is the Output Mode. Set this to Transmit for the H90 to send messages to other devices. Navigate to the last page of settings where we can find the MIDI – Transit menu. Here we can choose an expression device under Parameter and map it to a controller change number. Anytime we use an expression pedal or aux switch that has been mapped, it will send a MIDI controller change number from the midi out to downstream devices on the same MIDI Channel.