Make sure the MIDI IN/OUT mode is set to "MIDI" and not "USB". The owner's manual has a picture of this screen on page 49 step 5. Although these instructions are to connect using USB - you should set to the other setting (MIDI) for your configuration.

Owner's Manual: https://usa.yamaha.com/files/download/other_assets/7/812097/montage_en_om_b0.pdf

Also there are instructions on page 169 of the reference manual:

https://usa.yamaha.com/files/download/other_assets/9/812529/montage_en_rm_a0.pdf

Press: [UTILITY] -> "Settings" -> "MIDI I/O" then touch the "MIDI" selection under "MIDI IN/OUT"

Convention in above: [UTILITY] (or anything I surround by brackets) is a physical button on Montage. Things in quotes are generally items on the touchscreen.

Very much a newbie question . . . I just got my new Montage 7 today and having fun exploring the basics. I have a nice weighted keyboard I was hoping to try out as a midi controller for the Montage just to see how effective it would be. I connected a 5-pin Midi cable between the instruments but currently no control coming through. I expect there's a simple solution (probably a parameter set up). I'm just taking my first steps so would really appreciate a quick pointer

Connect a 5-pin MIDI cable between the MIDI OUT of your controller to the MIDI IN of MONTAGE.
Set the MIDI I/O = MIDI
This is found in [UTILITY] > “Settings” > “MIDI I/O”
Select MIDI I/O = MIDI so MIDI is active (green)

Touch “Advanced” in the second column
Set the “MIDI I/O Mode” = Single
Select a MIDI Channel on which you want to communicate. For example, if your controller is transmitting on channel 1, set the MONTAGE Single Mode to Channel 1 so that you can control it from the external keyboard.

Setting the MIDI I/O Mode to “Single” and selecting a single channel on which to communicate with the MONTAGE will allow your external controller to replace the MONTAGE’s own keyboard in your setup. You will be able to address the MONTAGE as a single synth controlling all Parts designated under KBD CTRL (max. 8 Parts), or as a multi-timbral Tone Engine where you address a single Part at a time, each on a separate MIDI channel.

The green KBD CTRL icon on the MONTAGE Home screen indicates when a Part 1-8 has been linked for real-time control from the MONTAGE Keys + Controllers. Using MIDI I/O Mode = Single, and addressing MONTAGE on the selected channel will let you control all KBD CTRL Parts the same as if you were playing on the MONTAGE.

Many thanks guys, working great now!

I'd missed the stage where you set Midi I/O Mode to "Single" under Advanced. Still didn't work initially but swapped out the MIDI cable and it burst into life!

Thanks again

Mark