For the Apple Computer keyboard A1644, you can follow these steps to charge it:
First, make sure your MAC is connected to a power source and turned on.
Turn on the MAC's power switch, which is usually located on the power button at the bottom of the computer.
After the power switch is turned on, wait for the computer to start charging. The charging process can take several minutes, depending on the capacity of the battery and the power of the charger.
When the computer starts charging, you can see the battery charging status displayed on the computer screen. When the battery is fully charged, the light on the charger will go out and the computer will automatically shut down.
After charging is complete, you can unplug the computer from the power outlet and turn the computer on. At this point, the computer should be fully charged and running normally.
Please note that different models of Apple computers and chargers may vary, so the specific charging steps may vary. If you have any questions about the specific charging procedure, you are advised to refer to Apple's official documentation or consult Apple customer service for accurate information.
Hope this answer was helpful! If you have any further questions, please feel free to let me know.
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