sparkfun Servo Trigger User Manual

In applications where the motors are moving non-trivial loads, it’s a better
bet to use heavier gauge wires and give each Servo Trigger a direct
connection to the power supply. The configuration is commonly known as
“star power.”
When in doubt, grab a multimeter, measure the current consumed, and
check whether VCC at the board input is falling below the rated voltage
when the servos are turning.
Troubleshooting
If there’s no motion when you actuate the input, first check that A and B are
not set the same, otherwise there’s no position change!
If you’re feeding the input with a logic signal from an external device, be
sure to drive the signal for more than 50 milliseconds. The PWM signal is
updated every 50 mSec, and events shorter than that may missed.
It’s also possible to set T shorter than the time it take the servo motor to
physically rotate. In this case, the motor may not reach B before returning
to A. Try turning up T, to see if a longer transition time allows the motor to
turn.
Expert Exercises
Customizing the Servo Trigger
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sparkfun Servo Trigger Specifications

General

Brand	sparkfun
Model	Servo Trigger
Category	Controller
Language	English

Summary

Understanding Hobby Servos

Electrical Connection

Details on the standard 3-pin plug and common color coding for RC servos.

Getting Started with Servo Trigger

Quick Start Guide

Instructions to build a circuit to demonstrate the Servo Trigger's functionality.

Servo Trigger Features and Configuration

Control Modes

Input Polarity Settings

Advanced Usage and Troubleshooting

Common Troubleshooting

Guidance on diagnosing and resolving issues like no motion or incorrect timing.

Customizing Servo Trigger

Firmware and State Machines

Firmware Modifications

Information on reprogramming the microcontroller and modifying firmware.

Timing Control

How to adjust transit times by modifying the timing table in the firmware.

Advanced Firmware Modes

Details on selecting and implementing different response modes via compile-time symbols.

Building Custom Behavior

Creating New State Machines