hybridgroup.gobot/examples/raspi_direct_pin_event.go

99 lines
2.6 KiB
Go

//go:build example
// +build example
//
// Do not build by default.
package main
import (
"fmt"
"time"
"gobot.io/x/gobot/v2"
"gobot.io/x/gobot/v2/platforms/raspi"
"gobot.io/x/gobot/v2/system"
)
const (
inPinNum = "21"
outPinNum = "24"
outPinInvertedNum = "26"
debounceTime = 2 * time.Second
)
var (
outPin gobot.DigitalPinner
outPinInverted gobot.DigitalPinner
)
// Wiring
// PWR Raspi: 1 (+3.3V, VCC), 2(+5V), 6, 9, 14, 20 (GND)
// GPIO Raspi: header pin 21 (GPIO9) is input, pin 24 (GPIO8) is normal output, pin 26 (GPIO7) is inverted output
// Button: the input pin is wired with a button to GND, the internal pull up resistor is used
// LED's: the output pins are wired to the cathode of a LED, the anode is wired with a resistor (70-130Ohm for 20mA) to VCC
// Expected behavior: always one LED is on, the other in opposite state, if button is pressed for >2 seconds the state changes
func main() {
board := raspi.NewAdaptor()
work := func() {
inPin, err := board.DigitalPin(inPinNum)
if err != nil {
fmt.Println(err)
}
if err := inPin.ApplyOptions(system.WithPinDirectionInput(), system.WithPinPullUp(),
system.WithPinDebounce(debounceTime), system.WithPinEventOnBothEdges(buttonEventHandler)); err != nil {
fmt.Println(err)
}
// note: WithPinOpenDrain() is optional, if using WithPinOpenSource() the LED's will not light up
outPin, err = board.DigitalPin(outPinNum)
if err != nil {
fmt.Println(err)
}
if err := outPin.ApplyOptions(system.WithPinDirectionOutput(1), system.WithPinOpenDrain()); err != nil {
fmt.Println(err)
}
outPinInverted, err = board.DigitalPin(outPinInvertedNum)
if err != nil {
fmt.Println(err)
}
if err := outPinInverted.ApplyOptions(system.WithPinActiveLow(), system.WithPinDirectionOutput(1),
system.WithPinOpenDrain()); err != nil {
fmt.Println(err)
}
fmt.Printf("\nPlease press and hold the button for at least %s\n", debounceTime)
}
robot := gobot.NewRobot("pinEdgeBot",
[]gobot.Connection{board},
[]gobot.Device{},
work,
)
robot.Start()
}
func buttonEventHandler(offset int, t time.Duration, et string, sn uint32, lsn uint32) {
fmt.Printf("%s: %s detected on line %d with total sequence %d and line sequence %d\n", t, et, offset, sn, lsn)
level := 1
if et == "falling edge" {
level = 0
}
err := outPin.Write(level)
fmt.Printf("pin %s is now %d\n", outPinNum, level)
if err != nil {
fmt.Println(err)
}
err = outPinInverted.Write(level)
fmt.Printf("pin %s is now not %d\n", outPinInvertedNum, level)
if err != nil {
fmt.Println(err)
}
}