hybridgroup.gobot/examples/raspi_servo.go

93 lines
2.2 KiB
Go

//go:build example
// +build example
// Do not build by default.
package main
import (
"fmt"
"log"
"time"
"gobot.io/x/gobot/v2"
"gobot.io/x/gobot/v2/drivers/gpio"
"gobot.io/x/gobot/v2/platforms/adaptors"
"gobot.io/x/gobot/v2/platforms/raspi"
)
// Wiring
// PWM Raspi: header pin 12 (GPIO18-PWM0), please refer to the README.md, located in the folder of raspi platform, on
// how to activate the pwm support.
// Servo: orange (PWM), black (GND), red (VCC) 4-6V (please read the manual of your device)
func main() {
const (
pwmPin = "pwm0"
wait = 3 * time.Second
fiftyHzNanos = 20 * 1000 * 1000 // 50Hz = 0.02 sec = 20 ms
)
// usually a frequency of 50Hz is used for servos, most servos have 0.5 ms..2.5 ms for 0-180°, however the mapping
// can be changed with options...
//
// for usage of pi-blaster driver just add the option "adaptors.WithPWMUsePiBlaster()" and use your pin number
// instead of "pwm0"
adaptor := raspi.NewAdaptor(adaptors.WithPWMDefaultPeriodForPin(pwmPin, fiftyHzNanos))
servo := gpio.NewServoDriver(adaptor, pwmPin)
work := func() {
fmt.Printf("first move to minimal position for %s...\n", wait)
if err := servo.ToMin(); err != nil {
log.Println(err)
}
time.Sleep(wait)
fmt.Printf("second move to center position for %s...\n", wait)
if err := servo.ToCenter(); err != nil {
log.Println(err)
}
time.Sleep(wait)
fmt.Printf("third move to maximal position for %s...\n", wait)
if err := servo.ToMax(); err != nil {
log.Println(err)
}
time.Sleep(wait)
fmt.Println("finally move 0-180° (or what your servo do for the new mapping) and back forever...")
angle := 0
fadeAmount := 45
gobot.Every(time.Second, func() {
if err := servo.Move(byte(angle)); err != nil {
log.Println(err)
}
angle = angle + fadeAmount
if angle < 0 || angle > 180 {
if angle < 0 {
angle = 0
}
if angle > 180 {
angle = 180
}
// change direction and recalculate
fadeAmount = -fadeAmount
angle = angle + fadeAmount
}
})
}
robot := gobot.NewRobot("motorBot",
[]gobot.Connection{adaptor},
[]gobot.Device{servo},
work,
)
if err := robot.Start(); err != nil {
panic(err)
}
}