I am trying to control my boss RV-500 with my Morningstar MC3
I have my rv-500 set to switch dn/up mode and I want to use the KC3 switches A and B to control the B switch and Tap/Ctrl on my RV-500 so that I can scroll through my presets using midi
Problem is when I send a CC to switch B which I think is CC#28 it’s unresponsive and I do not see what CC# to use for Tap/Ctrl
Any ideas how I can get this to work?
If you want to control the Tap/Ctrl switch on the RV500, you will need to assign a CC# to it on the RV500 device itself, then send that CC# from your MC3.
An alternative is to use MIDI Clock Tap to control tempo on the RV500, which we explain in the video below.
As an RV owner I have to disagree wirh @Brandon. He is technically correct but Boss did go out of their way to make the midi implementation of the 500 series as complicated as possible.
Midi clock is probably not an option, because it can’t be turned off on the patch level. If you want to control other pedals via clock you’ll run into trouble.
To control the tap tempo via CC you’ll have to take two steps.
Go to the menu, choose ‘MIDI’.
You’ll find ‘Effect sw’, ‘Effect sw A’ and ‘Effect sw B’. Here you can assign a CC# to the physical (!) switch. The Tap/Ctl switch is called ‘Effect sw’. (Why? Because Boss 
)
Sending this Cc will emulate a press of the actual switch. Note: You’ll have to send two CC messages!
The CC# you’ve assigned,
CC value 127 and CC value 0. To emulate a press and release of the switch.
Next step, assign the tap function to the tap/ctl switch. (This can probably be skipped because tap tempo is the default function, but I think it’s good to know). Go to the menu, choose ‘CONTROL’. The function of the tap/ctl switch can be edited. Choose ‘tap’ and make sure that the footswitch mode is set to ‘momentary’
Pro tip, you can assign tap tempo to the external footswitches Ctl1 and Ctl2. It works the same way but leaves the option to use the tap/ctl for other stuff. For example if you are planning to use the footswitches in A/B/C mode.
So I’m not actually trying to control tap tempo
I’m just trying to control that switch.
There’s a mode called switch down/up where you can use the B switch and “tap/Ctrl” switch to scroll up and down through presets and the A switch turns the preset on or off.
Basically I want to emulate a press of the B or tap/Ctrl switch
But whenever I send a message to the rv-500 I get no response for the B switch and I have tried assigning the tap/Ctrl and still don’t get a response
Hi,
that’s probably because you have to send two cc messages to perform a single action. Can you share a screenshot of your presets? If possible both the mc’s and the rv’s editor.
Note
Cc# 28 is ‘Effect A on/ Bypass’
Cc#29 is ‘Effect B on / Bypass’
That’s not what you are looking for. Go to the MIDI menu and assign a CC to ‘Effect Sw’ and ‘Effect B Sw’
This is what I was doing that doesn’t work.
So I tried what you said but maybe I’m not understanding the assign thing right. I went into the assign settings and turned on switch 2 , set it to moment, gave it a CC# and set it to control LED …still no response
Really don’t get why boss did this, this exact command works on the dd-500
It’s the wrong cc#. Cc 29 is effect b on/bypass. This is meant to be used in simul mode to toggle effect A and B independently. You have to use the CC that’s assigned to ‘Effect B SW’ and ‘Effect SW’. Those can be found in the ‘MIDi’ category of the menu.
There is no “effect b switch” in the midi menu…
Unless I’m looking at the wrong one. But I did not see one.
Deleted as I think not helpful, though maybe toggle mode is not necessary for this action?
That’s correct. Position should be set to ‘both’ for each message.
@chris1671 If you press ‘edit’ on the rv, you’ll find:
Patch
Bank (only in some modes)
Control
Assign
System
Midi
Go to Midi and scroll down until you find ‘Effect Sw’
Edit:
I just double checked. I was wrong. Effect Sw isn’t Tap/Ctl! Turns out the RV doesn’t have an assignable CC for the Tap switch! That’s possible on the DD only.
I’m very sorry for the confusion.
Which would imply that what you are trying to do is simply not possible.
However you could use the message scroll or a pc scroll counter on the mc to scroll through presets instead
As GuitarWolf mentioned before, an alternative is to set your CTL1 and 2 switches to bank up and down and use CC#80 and 81 (default cc assignments on the RV) to control bank up and down.
Can you elaborate on that last part regarding the scroll message?
UPDATE: Problem resolved!! The Morningstar PC scroll option worked like a charm and did exactly what I wanted to do! Thanks all for the help
