Digital Piano + Roland Synth Mod help

[markythesparky]

I own a Kawai ES920 digital piano and have recently purchased a Roland JD-08 synth module. I have connected them together via a 5 pin din Midi connector and everything works fine. However, I occasionally wish to play my piano and the synth mod together, with the synth sounding + 1 octave higher. Midi keyboards and synths usually have an octave shift button as standard, but my piano doesn't. There is an option on my piano, when using a split keyboard, to add +1 to +3 to the lower register, but this does not appear to affect the midi side of things. There is also 'pitch coarse' button on the synth module, but altering the pitch of any pre-programmed sound, changes the sound beyond recognition. Finally there is also an - oct + button on the synth module but that only works for the limited amount of keys built into the module - not an external keyboard. I know next to nothing about midi [as I'm sure you've already gathered] and so any help with a solution to my problem would be gratefully received. Thanks, Mark.