Can't move servo using raspberry pi adapter and servo driver

[ezerw]

Here is my code

package main

import (
	"log"
	"time"

	"gobot.io/x/gobot"
	"gobot.io/x/gobot/drivers/gpio"
	"gobot.io/x/gobot/platforms/raspi"
)

func main() {
	r := raspi.NewAdaptor()
	servo := gpio.NewServoDriver(r, "11")
	work := func() {
		gobot.Every(10*time.Second, func() {
			i := uint8(gobot.Rand(180))
			log.Printf("Moving servo to %d", i)
			servo.Move(i)
		})
	}
	robot := gobot.NewRobot(
		"servoBot",
		[]gobot.Connection{r},
		[]gobot.Device{servo},
		work,
	)

	robot.Start()
}

I've also have installed and running pi-blaster but still not able to move the servo. The program runs and I can see the logs but it seems that the signal is not being sent to the servo.

I tried using different pins and also following the indications on pi-blaster repo (You must use the GPIO number (BCM xx in the diagram below). but nothing works.

Any ideas how to debug or what's going on?

here the output of pi-blaster:

pi@raspberrypi:~/pi-blaster $ sudo ./pi-blaster
MBox Board Revision: 0xa020d3
DMA Channels Info: 0x7f35, using DMA Channel: 14
Using hardware:                   PWM
Number of channels:                32
PWM frequency:                 100 Hz
PWM steps:                       1000
Maximum period (100  %):      10000us
Minimum period (0.100%):         10us
DMA Base:                  0x3f007000
Initialised, Daemonized, Reading /dev/pi-blaster.

[erkexzcx]

#692

It's broken - this framework is useless for me. Instead I am using below code for my automation:

package main

import (
        "fmt"
        "log"
        "net/http"
        "time"

        piblaster "github.com/ddrager/go-pi-blaster"
)

const pin = 18 // GPIO18
var blaster = piblaster.Blaster{}

func main() {

        // Initialize blaster
        blaster.Start([]int64{pin})

        // Do a servo routine
        for i := 0; i < 7; i++ {
                setAngle(142)
                time.Sleep(600 * time.Millisecond)
                setAngle(129)
                time.Sleep(120 * time.Millisecond)
        }
        setAngle(48)

}

// Move servo to requested angle
func setAngle(angle uint8) {
        blaster.Apply(pin, angleToServo(angle))
}

// helper function - converts angle to servo value (aka 'map' function)
func angleToServo(val uint8) float64 {
        return (float64(val)-0)*(0.25-0.05)/(180-0) + 0.05
}

[gen2thomas]

I'm going to close this issue as a duplicate, because it is now referenced by an issue which collect all the various problems with raspi and gpio.servo.

[gen2thomas]

PWM frequency: 100 Hz

• pi-blaster needs to be set to 50Hz for most servos, otherwise the servo is not working at all or not working stable
• the current implementation in gobot maybe use the wrong range for the servo, this is fixed with adaptors(pwm): introduce scale option for servo #1046