Servo Trigger

Servo Trigger
This is a basic Servo Trigger with the servos running at full speed. The servo runs at it's maximum speed and does not stop in between the endpoints.

Features

• Six trigger input pins
• Five edge trigger inputs
• One level trigger input
• Servos run at full speed

Trigger inputs
There are six trigger input pins that activate when shorted to ground. The pins are labeled "Switch Inputs" on the circuit board. A row of ground pins is provided so all that's needed is to short the pair of pins for an input.

Pin	Trigger Type	Description
4	Edge trigger	Move to advance position
6	Edge trigger	Move to retract position
7	Edge trigger	One full cycle (to retract position)
10	Edge trigger	Half cycle
20	Edge trigger	Run/stop toggle
21	Level trigger	Run continuously

Control Knobs
Three trimpots with knobs control these settings:

• Servo retract position
• Servo advance position
• Seek time

Configuration Console
Servo trigger can be plugged into a USB port and any serial terminal at 115200 baud can be used to configure more settings. Settings that can be changed are:

• Servo pulse width range (type of servo)
• Seek time range

Specifications

• Power supply: 5V to 6V (whatever the servo prefers)
• Dimensions: 37mm x 41mm

Optional Input Conditioning
Pads are provided on the circuit board for:

• Stronger pullup resistors (e.g. 1K)
• Filter capacitors (e.g. 100nF)

Design Documents

Schematic Diagram	servo_trigger_schematic.pdf
PCB Gerbers	gerbers_OA22.zip
Arduino Source Code	Arduino.ino

Parts List

C1-C6	6	100nF typical	Noise suppression capacitor (optinal)
J1	1	.1" 2 pin JST	Power connector
J2	1	.1" 2x6 header	Power connector
J3	1	.1" 1x3 header	Power connector
R1-R6	6	1K typical	Strong pullup resistor (optinal)
RV1-RV3	3	10K trimpot	Knobs
SW1	1	small button	Tactile switch for setup
U1	1	ESP32-C3	Microprocessor
PCB	1	OA22	Printed circuit board

Build Pictures

Breadboard development

Boards from PJRC

Finished Board