pipoint/servoblaster.go

44 lines
1 KiB
Go

// Copyright 2017 Google Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
package pipoint
import (
"fmt"
"os"
"gobot.io/x/gobot/sysfs"
)
const (
path = "/dev/servoblaster"
)
type ServoBlaster struct {
Pin int
}
// SetDuty sets the servo period in ns.
func (s *ServoBlaster) SetDuty(period int) (err error) {
file, err := sysfs.OpenFile(path, os.O_WRONLY, 0644)
defer file.Close()
if err != nil {
return
}
_, err = file.Write([]byte(fmt.Sprintf("%d=%dus\n", s.Pin, period/1000)))
return err
}