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Revision to Using servos and controlling unused IO pins

David Crocker

== Important note on connecting servos ==
-When a servo stops moving, it can pump a large amount of energy into the +5v rail due to regenerative braking. If unchecked, this may increase the voltage of the +5V rail above the safe limit. The 1.04 revision of the Duet 2 WiFi/Ethernet has an extra 220uF capacitor on the 5v rail to help absorb this, so does the Duet 2 Maestro. Older Duets don't. So when using servos with them it is advisable to add your own 220uF capacitor between the +5V and ground servo wires.
+When a servo stops moving, it can pump a large amount of energy into the +5v rail due to regenerative braking. If unchecked, this may increase the voltage of the +5V rail above the safe limit. The 1.04 revision of the Duet 2 WiFi/Ethernet has an extra 220uF capacitor on the 5v rail to help absorb this, so does the Duet 2 Maestro. Older Duets don't. So when using servos with them it is advisable to add your own 220uF capacitor between the +5V and ground servo wires. This applies whether the servo is connected directly to the Duet or to an attached DueX expansion board or expansion breakout board.
== Logical pin numbers ==

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