I've got a Raspberry Pi 3B with which I want to control a motor using PWM. In Python this works great to gradually increase the voltage of a GPIO pin from 0% to 100% (100% == 3.3V):
import RPi.GPIO as GPIO
from time import sleep
PWM_PIN = 13
GPIO.setmode(GPIO.BCM)
GPIO.setup(PWM_PIN, GPIO.OUT)
p = GPIO.PWM(PWM_PIN, 1000)
p.start(0)
for i in range(101):
print(i)
p.ChangeDutyCycle(i)
sleep(0.1)
sleep(5) # Keep the voltage at 100% for 5 seconds, after which the program ends
Since I'm writing my program in Go I now want to do the same thing (or similar) in Go. So this is my shot at it.
package main
import (
"fmt"
"time"
rpio "github.com/stianeikeland/go-rpio"
)
const (
PWM_PIN = 13
)
func main() {
err := rpio.Open()
if err != nil {
panic(err)
}
motor_pin_pwm := rpio.Pin(PWM_PIN)
motor_pin_pwm.Mode(rpio.Pwm)
motor_pin_pwm.Freq(1000)
motor_pin_pwm.DutyCycle(0, 100)
fmt.Println("Waiting...")
time.Sleep(5 * time.Second)
fmt.Println("Start the increase...")
for i := 1; i <= 100; i++ {
fmt.Println(i)
motor_pin_pwm.DutyCycle(uint32(i), 100)
time.Sleep(100 * time.Millisecond)
}
time.Sleep(5 * time.Second)
}
There's an example of using go-rpio to control PWM here. The example is meant to control a LED instead of a motor, but I guess the code should be very similar (if not the same). The example uses different values, so I messed around with the values a bit but with no results.
What am I missing here?
