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ultimachine / RAMBo

3D Printer electronics
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servo connection? #17

Closed tkole closed 10 years ago

tkole commented 11 years ago

Is is possible to connect a servo to the RAMBO board for use with the latest Marlin bed leveling features? If so, where?

johnnyr commented 10 years ago

The best place to connect a servo is the PWM Ext header. You will need to make an adapter cable or modify the one that comes on the servo. The pins are in the order = 5V,GND,13,2,5,4.

I would use pin 4 or 5. Pin 13 is shared with the LED. 2 is shared with Fan-2 output.

kakaroto commented 10 years ago

I used the MX extension since it's a motor so it made sense. Any reason why PWM Ext would be a better choice than MX Ext? This is the code I added to pins.h for Marlin :

#ifdef NUM_SERVOS
  #define SERVO0_PIN         22

  #if NUM_SERVOS > 1
    #define SERVO1_PIN         24
  #endif

  #if NUM_SERVOS > 2
    #define SERVO2_PIN         23
  #endif
#endif
johnnyr commented 10 years ago

You are right kakaroto. It can be any digital pin. In my mind the motor extensions are for stepper motors, but they are equally suited for servos.