Lee S. HOPE THIS HELPS ? I Wrote this when I had T2 but T5 will be basically the same.

Setting up Tyros to NP30 or any other lower board as a Twinset.
As a number of players now adding a lower keyboard, I thought I would again provide Instructions.

TWINSET. Tyros 2 + NP30 Midi Setup but Other models Tyros the midi setup I assume is similar.

T2. Function \ Split points. Set Split Points R1 & R2 to C1.(last key left) R3 to C1#. Beware that previous made Registrations saved will alter this.

NP30 Midi Out to T2 Midi In. Only one lead required.

T2. Function \ Midi \ Press Edit.
Page to Receive....Set CH1 change from Song to LEFT. NP30 now play T2 Left Voices.
Page to Chord detect….Tick CH1.

Volume Control of NP30 is turned OFF as it's acting only as a dummy to trigger T2 Chords \ Styles \ Voices.

I play NP30 chords around middle C (OrganStyle) so the left voice TUNING requires setting Minus 1 octave….Easy way to do this is when switching on the NP30….Whilst Holding down the NP30 Grand Piano Voice Button…Press C above middle C. This will transpose the NP30 up 1 Octave so you can now play left hand chords around middle C this will play the T2 Left Voice at correct Octave.

Note The Left Hand Voice ON-OFF Button of the T2 does not work in this setup…..If you want to play with the T2 Left voice ON from the NP30 to Tyros do the following.
Make a User Midi Template by going to Function \ Midi. Save As (name ?) Suggest Name as LOWER ON into USER. Lower ON is because we previously changed the CH1 from Song to LEFT.

Page to Receive....Set CH1 change back to SONG.
The Midi Template settings above I did another Template Changing RECEIVE CH1 to SONG and Saved As LOWER OFF into USER. This enables you to switch off T2 left voice if not required as on the T2 left voice switch does operate on this setup.

Instructions are far easier to do than put into Print but the above should get you started.

Graham UK.

PS. Richard Bower (Yamaha Demonstrator) did an excellent article for Twinset in an early Yamaha Club Magazine.