mirror of https://github.com/kidoman/embd
57 lines
1.2 KiB
Go
57 lines
1.2 KiB
Go
// Package servoblaster allows interfacing with the software servoblaster driver.
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//
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// More details on ServoBlaster at: https://github.com/richardghirst/PiBits/tree/master/ServoBlaster
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package servoblaster
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import (
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"fmt"
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"log"
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"os"
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)
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// ServoBlaster represents a software RPi PWM/PCM based servo control module.
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type ServoBlaster struct {
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initialized bool
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fd *os.File
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// Debug level.
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Debug bool
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}
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// New creates a new ServoBlaster instance.
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func New() *ServoBlaster {
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return &ServoBlaster{}
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}
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func (d *ServoBlaster) setup() (err error) {
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if d.initialized {
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return
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}
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if d.fd, err = os.OpenFile("/dev/servoblaster", os.O_WRONLY, os.ModeExclusive); err != nil {
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return
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}
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d.initialized = true
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return
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}
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// SetMicroseconds sends a command to the PWM driver to generate a us wide pulse.
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func (d *ServoBlaster) SetMicroseconds(channel, us int) (err error) {
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if err = d.setup(); err != nil {
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return
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}
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cmd := fmt.Sprintf("%v=%vus\n", channel, us)
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if d.Debug {
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log.Printf("servoblaster: sending command %q", cmd)
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}
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_, err = d.fd.WriteString(cmd)
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return
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}
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// Close closes the open driver handle.
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func (d *ServoBlaster) Close() (err error) {
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if d.fd != nil {
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err = d.fd.Close()
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}
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return
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}
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