Switch between computer mode & monitor mode
I connect my MacBook Air with my iMac using a mini DisplayPort cable at home. How can I switch the monitor mode of iMac to pc mode and vice versa without unplugging the cable. Thanks!
see > https://support.apple.com/en-us/HT204592
How to use target display mode
- Make sure that your iMac is started up and meets the system requirements above.
- Make sure that the other Mac is started up and logged in to a macOS user account.
- Connect the two computers using the appropriate Mini DisplayPort or Thunderbolt cable.
- You can use more than one iMac as a display, if each iMac is using a Thunderbolt cable to connect directly to a Thunderbolt port on the other Mac (not the other iMac).
- Press Command-F2 on the keyboard of the iMac. You should now see the desktop of the other Mac.
- To exit target display mode, press Command-F2 again. Or disconnect the cable, or restart either Mac.