SparkFun
SparkFun Servo Trigger - Continuous Rotation
The SparkFun Continuous Rotation (CR) Servo Trigger lets you control a hobby CR servo motor without any programming. Simply connect a servo and a switch, adj...
The SparkFun Continuous Rotation (CR) Servo Trigger lets you control a hobby CR servo motor without any programming. Simply connect a servo and a switch, adjust the three onboard potentiometers, and the board handles everything — when the switch changes state, the servo transitions between two speeds/directions over a configurable time period.
Built around an ATtiny84 microcontroller with pre-loaded CR servo firmware, the board draws just 5 mA at 5 V and supports daisy-chaining multiple boards by connecting VCC and GND pads together.
Key Features
- No Programming Required – Control CR servos with just a switch and three pots
- Three Potentiometers – A (switch-open speed), B (switch-closed speed), T (transition time)
- Configurable Input Polarity – Works with switches or logic signals
- Configurable Response Mode – Choose how the servo responds to input changes
- Daisy-Chainable – Connect multiple boards via VCC/GND pads
- ISP Header – Reprogram the ATtiny84 for custom firmware
- Low Power – ~5 mA draw at 5 V (servo current additional)
Specifications
- Recommended Voltage: 5 V DC
- Maximum Voltage: 5.5 V DC
- Current Draw: ~5 mA (board only)
- Servo Compatibility: Analogue continuous rotation servos
Ideal For
- Robotics projects without a microcontroller
- Automated displays and animatronics
- Kinetic art and interactive installations
Resources
Jargon buster
Plain-language definitions for the technical terms used above.
- ISP
- An image signal processor is hardware that helps process raw camera data into usable images or video. It matters for vision projects because it can improve camera handling and reduce the processing load on the main CPU.
- microcontroller
- A microcontroller is a small computer on a chip that runs your program and controls connected inputs and outputs. For this product, it is the part that reads buttons and sensors, drives the display and speaker, and communicates over Bluetooth.
- servo
- A servo is a motor with built-in position control, usually told to move to a specific angle by a control signal. It matters when you need repeatable movement, such as steering, arms, flaps, or linkages, rather than continuous spinning.
- servo motor
- A motor module that moves to a commanded angle rather than simply spinning freely. It matters for robotics and mechanisms because it is useful for steering, arms, gates and other parts that need controlled position.
Find this product in
Brands
Robotics & Motion
SparkFun Servo Trigger Continuous Rotation Schematic
Schematic · 75.4 KB · Click any page to view full size
555 Timer Datasheet
Datasheet · 4.4 MB · Click any page to view full size
Supplier page — sparkfun.com
Supplier Description · 595.1 KB · Click any page to view full size
Resources & Downloads
Guides, code examples, and more
Related Tutorials
Free guides on learn.littlebird.com.au
