The FDC speed is more impressive when you realize the Amstrad CPC’s tape loads at only 2 kbits/s in fast mode. Note: tape loading can be way faster than that if an MP3 player is used instead of a real physical tape, as it has been demonstrated here: https://youtu.be/MAIsOIwgJWA
Note: Some FDC commands don't require the motor to be on. For example, the seek command or recalibrate commands that moves move the floppy drive head works work fine with the motor off. [https://64nops.wordpress.com/2021/07/10/a-la-decouverte-du-fdc-episode-2/ Source]
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