Mac Power via Keyboard Shortcut?

Question

many mac keyboards have a power button. Is there a way to mimic this power button shortcut from an arduino?

• Greg Hewgill: Perhaps you could be clear what you mean by "mimic". Do you want your Arduino to be able to turn on (or off) your Mac without manual intervention?
• Anonymous Penguin: Also, what keyboard? Some Mac laptops have a power button for the computer, where others have one to shut off the wireless keyboard.
• jippie: You have to research HID keyboard codes and its protocol. The power button is a regular key on the keyboard with a specific key code and specific a data frame. Leonardo can probably do it, most somewhat older design Arduino's can't act as a USB HID.
• sachleen: The Arduino can emulate a keyboard from which you can send a series of keystrokes to turn off the computer. Not sure you'll be able to mimic the hardware button. There are a few questions that are related: arduino.stackexchange.com/search?q=hid+is%3Aquestion
• Brian: I have a mac mini rack holder that has a front panel with power button. It connects and controls the mac mini with USB only. I want to replicate this power signal sent over the USB with an arduino instead.

Answer 1

There are multiple ways to do that.

• You could use an Arduino Leonardo as a keyboard, then send a shortcut command to shut down or sleep the computer. You can edit these from System Preferences>Keyboard>Shorcuts>Services. The keycode 0x66 does not work for mac, but may for other operating systems source

• You could write a small program (I'd do it in Python) which communicates with the Arduino over the serial port and shuts down the Mac if the Arduino wants it to.

• You could sacrifice an USB keyboard and use a relay to "press" the power key.