If you as me have single monitor and 2 Mac devices (for example, I have corporate Macbook and personal Mac Mini) you may want to use the same monitor for both devices. And you may want to switch between them without unplugging and plugging cables or selecting input source using monitor buttons.

In this post I will show you how to configure hotkeys for that.

Hardware

You will need a monitor with multiple input sources. For example, I have Dell S2722QC tt has 2 HDMI ports and 1 USB-C port where:

  • Macbook Air connected to port HDMI-2
  • Mac Mini connected to port USB-C-1

Software

There is app called BetterDisplay that has a lot of powerful features. But for our case we need only one feature - change display inputs using DDC.

Install it on both Macs. You will have 14 days trial period with all PRO features.

Enable Accessibility for BetterDisplay in System Settings -> Privacy & Security -> Accessibility.

Then try to switch input source by clicking on BetterDisplay icon in the menu bar -> DDC Input Source -> Select next port.
Menu Shot Input Choose

If it works, you can continue to the next step. Otherwise check if your monitor supports DDC protocol and ensure Accessibility is enabled for BetterDisplay.

If you are ready to pay 19$/19€ x2 for both Macs you can buy BetterDisplay. And then configure hotkeys in the app settings Settings -> Keyboards -> Custom keyboard shortcuts -> DDC Input Source.

Click “Record Shortcut” and press the key combination you want to use, for example CMD + F1 and CMD + F2.

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Free option

If you like me don’t want to pay for 40$ for single feature there is a hacky way to do it.

We need an app that can handle hotkeys and run shell commands. I use Raycast, so called “Spotlight on steroids” and it can handle custom hotkeys. Or you can use any other app you like.

Configuring shell command

Before configuring Raycast we need to know ddc value for each input source. To do so, go to Settings -> Displays -> “Your monitor name” -> DDC Input Sources, and save IDs from Value column for each input source:

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In my case it’s 18 for HDMI-2 and 25 for USB-C-1.

Then create a directory ~/raycast-scripts and put there a script change-input-source.sh:

#!/bin/bash

# See full documentation here: https://github.com/raycast/script-commands
#
# Required parameters:
# @raycast.schemaVersion 1
# @raycast.title Switch Monitor Input Source
# @raycast.mode silent
#
# Optional parameters:
# @raycast.icon 🖥️
# @raycast.packageName Raycast Scripts

DEST_ID=18 <PUT YOUR DDC ID HERE>
DEST_NAME="Home Mac Mini"

# PUT YOUR ACTUAL HOSTNAME
if [ `hostname` == "Aliks-Mac-mini.local" ]; then
  DEST_ID=25 <PUT YOUR SECOND DDC ID HERE>
  DEST_NAME="Work Macbook Air"
fi

echo "Switching monitor input source to $DEST_NAME"
/Applications/BetterDisplay.app/Contents/MacOS/BetterDisplay set -ddc=$DEST_ID -vcp=inputSelect

After that try to run it in terminal:

chmod +x ~/raycast-scripts/change-input-source.sh
~/raycast-scripts/change-input-source.sh

If it works, you can continue to the next step.

Configuring Raycast

  1. Open Raycast and go to Settings -> Extensions -> Search for Scripts
  2. Click on Add Script Directory and select ~/raycast-scripts
  3. Click on Record Shortcut for newly added script and press the key combination you want to use, for example CMD + F1 on first Mac and CMD + F2 on second.

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And that’s it! Now you can switch input source using hotkeys.