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Servos

Up to 16 servos on one PCA9685 board. Set each one's safe range by moving the real servo, then pose your droid with them in sequences.

What it’s for

Section titled “What it’s for”

Servo Config holds your servos: which channel each is plugged into, its name, and its safe range, the furthest it may move each way and where it rests. The moves themselves are made on the Sequences page. Each servo’s card says which sequences move it; click one to open it.

Quick start: add a servo

Section titled “Quick start: add a servo”
  1. + Add a servo: pick the channel it’s plugged into, and give it a name.
  2. In Find the limits, move the real servo slowly towards one end with the dial, slider or nudges, until it stops travelling or starts to buzz. Back off a little.
  3. Press Set as minimum (or Set as maximum). Do the other end, then Set as rest.
  4. Save servo.

The safe range

Section titled “The safe range”

The range is a pulse width in µs (microseconds). Most servos are happy between 1000 and 2000 µs; some accept 500–2500. Past what yours can do, it stalls against its end stop, which strains it. The gauge on each card shows the range, the rest position and, live, where the servo is now.

  • Find the limits can go past the current range (400–2600 µs), so you can find a new one. Clear the stops opens the range right out to start again.
  • Narrowing a range warns you which sequences have moves outside it.
  • Changing a servo’s channel later moves it in every sequence too.

Trouble?

Section titled “Trouble?”
  • The servo doesn’t move: connect the radio or turn on Bench mode, and check the servo driver’s pins on Pin Assignment (they apply after a restart).
  • It buzzes at the ends: its range is wider than it can travel. Find the limits again.