mirror of https://github.com/kidoman/embd
66 lines
1.9 KiB
Go
66 lines
1.9 KiB
Go
/*
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* Copyright (c) Kunal Powar 2014
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*
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* Permission is hereby granted, free of charge, to any person obtaining a copy of this software and
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* associated documentation files (the "Software"), to deal in the Software without restriction,
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* including without limitation the rights to use, copy, modify, merge, publish, distribute,
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* sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is
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* furnished to do so, subject to the following conditions:
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*
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* The above copyright notice and this permission notice shall be included in all copies or
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* substantial portions of the Software.
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*
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* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT
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* NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
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* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
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* DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
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*/
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// Package servo allows control of servos using a PWM controller.
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package servo
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import (
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"github.com/cfreeman/embd/util"
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"github.com/golang/glog"
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)
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const (
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minus = 544
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maxus = 2400
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)
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const (
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// DefaultFreq represents the default (preferred) freq of a PWM doing servo duties.
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DefaultFreq = 50
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)
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// A PWM interface implements access to a pwm controller.
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type PWM interface {
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SetMicroseconds(us int) error
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}
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type Servo struct {
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PWM PWM
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Minus, Maxus int
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}
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// New creates a new Servo interface.
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func New(pwm PWM) *Servo {
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return &Servo{
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PWM: pwm,
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Minus: minus,
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Maxus: maxus,
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}
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}
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// SetAngle sets the servo angle.
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func (s *Servo) SetAngle(angle int) error {
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us := util.Map(int64(angle), 0, 180, int64(s.Minus), int64(s.Maxus))
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glog.V(1).Infof("servo: given angle %v calculated %v us", angle, us)
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return s.PWM.SetMicroseconds(int(us))
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}
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