Input device and system including input device

An input device, comprising:

• a keycap configured to be depressed;
• a first electrode configured to move in a specified direction in response to depression of the keycap;
• a second electrode arranged facing the first electrode such that a capacitance between the first electrode and the second electrode changes in accordance with a depression amount of the keycap, the second electrode being connected to ground;
• a chargeable capacitor;
• a sensor part configured to detect a value of a charge parameter which changes in accordance with a charge amount of the capacitor;
• a switching part configured to switch connection state between a first state in which a power supply and the first electrode are connected to each other and the first electrode and the capacitor are not connected to each other, and a second state in which the power supply and the first electrode are not connected to each other and the first electrode and the capacitor are connected to each other;
• and
• a third electrode arranged so as to come into contact with the first electrode when a depression amount of the keycap is equal to or greater than a specified amount, the third electrode being connected to the power supply.