Servoextension

Servo Support Extension

This extension adds support for servo motors. Servo motors operate be sending a series of pulses. The duration of each pulse instructs the servo motor to move to a particular angular location.

The activated servos will be pulsed at a firmware-configured rate which is set to 20ms by default.

Extension Orders

Activate/Deactivate Servo

This Order activates or deactivates a stepper, that is, it starts or stops emitting pulses on the corresponding device pin. The initial pulse width value is supplied when activating the servo; otherwise the servo will be deactivated.

Table 1. Parameter

Byte	Content
0	device number
1	initial pulse width in us (MSB) [optional]
2	initial pulse width in us (LSB) [optional]

Replies

• OK: The reply parameter contains no data.

Set Stepper Position

This Order sets the pulse width to generate for the servo motor (which in turn determines the resulting angular position based on the servo motor’s pulse width characteristics).

Table 2. Parameter

Byte	Content
0	device number
1	desired pulse width in us (MSB)
2	desired pulse width in us (LSB)

This order can also be queued using the Queue Command Wrapper if the basic move extension is supported.

Replies

• OK: The reply parameter contains no data.