Begin of hardware requirements

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+## Hardware requirements and peripherals
+
+### Motor drivers
+[High-power motor drivers](https://www.pololu.com/category/11/brushed-dc-motor-drivers)
+
+We have to control 2 motors so a 2 channel driver should be the best choice.
+TBD which one depending on the motor current needs.
+
+### Encoders
+
+TBD
+
+### PIN requirements
+##### pin needed for encoders:
+2 GPIO for each encoder, 4 GPIO total
+
+##### pin needed for drivers:
+* 6 GPIO for fault indicators, sleep inputs, motor directions
+* 2 PWM pins for motor speed control
+* 2 Analog pins for current sense
+
+##### Total pin count:
+* 10 GPIO
+* 2 PWM
+* 2 Analog